Dr. Michael Eisenberg: Improving Male Sexual Health, Function & Fertility

00:00:00.000 | - Welcome to the Huberman Lab Podcast,

00:00:02.280 | where we discuss science and science-based tools

00:00:04.880 | for everyday life.

00:00:05.900 | I'm Andrew Huberman,

00:00:10.360 | and I'm a professor of neurobiology and ophthalmology

00:00:13.400 | at Stanford School of Medicine.

00:00:15.200 | My guest today is Dr. Michael Eisenberg.

00:00:17.840 | Dr. Michael Eisenberg is a medical doctor

00:00:20.080 | specializing in urology

00:00:21.760 | and an expert in male sexual function and fertility.

00:00:25.400 | He is both a clinician who sees patients,

00:00:27.860 | as well as a research scientist,

00:00:29.880 | having published over 300 peer-reviewed articles

00:00:32.900 | on male sexual function, urology, and fertility.

00:00:36.040 | And he is considered one of the world's foremost experts

00:00:38.840 | in male sexual health.

00:00:40.460 | Today, we discuss a broad range of topics

00:00:42.300 | important to all men,

00:00:43.760 | including erectile dysfunction and function.

00:00:46.640 | We also discuss prostate health and urinary health.

00:00:49.620 | We discuss fertility and sperm count.

00:00:52.100 | We discuss even topics seemingly esoteric,

00:00:55.360 | such as why penile lengths are actually increasing over time

00:00:59.240 | while sperm count seem to be decreasing.

00:01:01.640 | Today, you'll also learn some very interesting surprises,

00:01:04.440 | such as the fact that a very, very small percentage

00:01:07.460 | of erectile dysfunction

00:01:08.800 | actually stems from hormone dysfunction.

00:01:11.480 | Rather, the vast majority of erectile dysfunction

00:01:14.360 | stems from issues that are either vascular,

00:01:16.800 | that is related to blood flow, or neural.

00:01:19.040 | And today, you'll learn about a large variety of treatments

00:01:21.600 | for erectile dysfunction.

00:01:23.080 | Dr. Eisenberg also dispels a lot of common myths

00:01:26.120 | that you hear out there,

00:01:27.640 | both on the internet and in popular culture,

00:01:30.640 | that relate to male sexual health and function.

00:01:33.280 | By the end of today's episode,

00:01:35.000 | I assure you that you will have a thorough understanding

00:01:38.040 | of what male sexual health is,

00:01:40.000 | how it relates to other aspects of health,

00:01:42.440 | and how to think about treating, maintaining,

00:01:44.480 | and improving all aspects of male sexual health,

00:01:47.440 | fertility, and function.

00:01:49.200 | Before we begin, I'd like to emphasize that this podcast

00:01:51.680 | is separate from my teaching and research roles at Stanford.

00:01:54.240 | It is, however, part of my desire and effort

00:01:56.380 | to bring zero cost to consumer information about science

00:01:59.020 | and science-related tools to the general public.

00:02:01.680 | In keeping with that theme,

00:02:02.740 | I'd like to thank the sponsors of today's podcast.

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00:04:17.200 | And now for my discussion with Dr. Michael Eisenberg.

00:04:20.840 | Dr. Eisenberg, welcome.

00:04:22.540 | - Thank you, good to be here.

00:04:23.860 | - I've been looking forward to talking to you

00:04:25.140 | for a long time because these days we hear a lot

00:04:28.840 | about the diminishing quality of sperm,

00:04:33.540 | which in some ways seems to be attached to the conversation

00:04:35.840 | about diminishing quality of environment, people,

00:04:40.840 | intelligence, you know, there's a lot woven

00:04:44.120 | into this statement that sperm quality is declining.

00:04:47.640 | And some of it, I think people assume

00:04:51.920 | is related to environmental changes.

00:04:54.440 | Some of it, I think people assume it are related

00:04:57.320 | to changes in behaviors.

00:05:00.200 | So maybe less exercise, less sunlight, who knows?

00:05:04.060 | Hopefully you'll tell us what's really going on.

00:05:05.880 | But the first question I have is,

00:05:08.020 | is sperm quality actually declining?

00:05:11.120 | And regardless, what is sperm quality?

00:05:15.280 | - Yeah, great question.

00:05:16.320 | So I think it's very controversial,

00:05:18.720 | I think is your question alludes to.

00:05:20.440 | So I think we'll start by just talking

00:05:21.880 | about what sperm quality is and why it's important.

00:05:24.880 | So for reproduction, as you've covered on the podcast before

00:05:27.660 | a man makes semen and that has sperm in it.

00:05:30.720 | And so when we're talking clinically about a semen analysis,

00:05:33.440 | there's a few things we look at.

00:05:34.560 | We look at the amount of ejaculate semen that comes out.

00:05:37.820 | We look at the sperm, how many there are.

00:05:40.520 | We look at their motility or movement.

00:05:42.240 | We look at their morphology or shape.

00:05:44.200 | There's some more advanced testing

00:05:45.520 | that's done in rare cases,

00:05:46.640 | looking at fragmentation of DNA, for example,

00:05:48.960 | or there's some newer tests

00:05:49.800 | looking at epigenetic profiles of sperm.

00:05:52.480 | But essentially these are all markers of fertility.

00:05:55.000 | So fertility in itself is a team sport, right?

00:05:58.000 | So it's hard to label a man as fertile or not fertile

00:06:02.480 | without knowing about his partner.

00:06:04.200 | But nevertheless, based on these different parameters,

00:06:08.460 | we try and quantify how likely a man is

00:06:10.900 | to be able to achieve a pregnancy.

00:06:12.660 | So the World Health Organization every decade or so

00:06:15.380 | looks over the existing literature

00:06:17.060 | and defines these different cut points

00:06:18.600 | of what's normal or what's sub-fertile for those levels.

00:06:21.940 | So that's sort of the backdrop of what semen is

00:06:25.080 | and how these tests are done

00:06:27.080 | or what these tests represent.

00:06:29.220 | Now, the question of whether they've declined over time

00:06:32.280 | has been a question for a number of years.

00:06:36.240 | There was a landmark paper in the early '90s

00:06:38.980 | by Carlson and a group in Denmark

00:06:41.580 | that showed this temporal decline

00:06:43.360 | over the last 50 years from that time point.

00:06:45.900 | And so what the investigators had done

00:06:47.640 | is looked over the literature

00:06:49.400 | for studies that reported semen quality around the world

00:06:53.240 | and noted that the quality in the earliest studies,

00:06:56.600 | like in kind of the mid 20th century, were here,

00:07:00.360 | and then over time they had sort of declined

00:07:02.300 | the more recent studies.

00:07:04.820 | Now, that study was very controversial.

00:07:06.520 | There was questions about waiting from different studies,

00:07:09.220 | because as you can imagine,

00:07:10.920 | there's not a lot of early studies,

00:07:12.260 | so putting a lot more importance on those

00:07:15.060 | rather than some of the later ones.

00:07:16.980 | And so since then, there's been many other studies

00:07:20.720 | that have come out in time.

00:07:23.320 | And even today, it remains very controversial.

00:07:26.340 | I think if I were to say that I believe there's a decline,

00:07:30.760 | some of my colleagues and friends

00:07:31.940 | would be very upset with me.

00:07:33.320 | If I say I don't believe it, some of my colleagues

00:07:34.980 | and friends would be very upset with me.

00:07:36.180 | So I would say that my opinion really varies

00:07:38.980 | based on whose paper I've read,

00:07:40.340 | and there's some very convincing studies on each side of it.

00:07:45.220 | Most recently, just in the last year or so,

00:07:47.220 | there was a meta-analysis of tens of thousands of men

00:07:51.160 | where they looked at, again, a host of these studies

00:07:53.740 | over the last number of decades all around the globe.

00:07:57.640 | So prior studies really just focused

00:07:59.940 | on the Western Hemisphere, Western countries,

00:08:01.960 | 'cause there was more data from that.

00:08:03.340 | But more recently, we've gotten a lot of data

00:08:05.460 | from Africa, from Asian countries as well.

00:08:08.660 | And those also support this decline.

00:08:10.740 | So one of the counterarguments to why we're seeing that

00:08:14.860 | is just sort of an evolution of techniques over time.

00:08:18.460 | So that's one of the popular questions

00:08:23.380 | about whether there's really a true decline.

00:08:25.680 | I think as you're alluding to why there would be a decline

00:08:29.740 | is also unknown, but you've sort of labeled perfectly

00:08:34.740 | the kind of most common hypotheses,

00:08:37.440 | so whether it's an environmental exposure.

00:08:39.200 | A lot of things have changed over the last 50 years,

00:08:41.980 | and I think chemical exposure is certainly one of those.

00:08:44.480 | And there have been some fairly convincing

00:08:47.320 | preclinical studies, so mostly done in animals

00:08:50.640 | that show that exposure to different chemicals,

00:08:52.660 | phthalates, BPA, other things, may actually harm

00:08:58.400 | reproductive function for men and for women as well.

00:09:01.400 | And so it may be that these chemicals

00:09:04.460 | that we're being exposed to as kids and adults,

00:09:08.060 | or even probably more sinisterly

00:09:12.100 | when we're kind of developing in utero,

00:09:15.500 | that may be kind of the most harmful exposure.

00:09:18.500 | But there's also been an obesity epidemic as well,

00:09:21.420 | and there's a strong link between

00:09:22.840 | a man's reproductive function and body weight.

00:09:26.820 | And so that's also thought to play a role

00:09:30.020 | in some of this too.

00:09:31.180 | So I think there are convincing studies,

00:09:34.460 | but the other, I guess, aspect to this

00:09:36.260 | is that there's variations in semen quality

00:09:38.420 | around the country and around the world.

00:09:40.300 | There's geographic variation.

00:09:41.820 | And so that's also sort of an unknown explanation.

00:09:46.820 | There could be different genetic compositions of men,

00:09:52.380 | and so there's different reproductive potential

00:09:53.860 | in that source.

00:09:54.700 | There could be different environmental exposures,

00:09:56.240 | diet, exercise, lifestyle.

00:09:58.420 | And there's a famous study done a number of years ago

00:10:02.200 | where they looked at semen quality among fathers.

00:10:05.300 | So these are men that had achieved a pregnancy,

00:10:07.300 | and at the first prenatal visit,

00:10:09.800 | they had the fathers give a semen sample.

00:10:12.940 | And so this has done four centers around the country.

00:10:14.900 | I think one in California, there was one in the Midwest,

00:10:19.900 | there was one in New York.

00:10:22.220 | So they basically found that semen quality

00:10:24.740 | was highest in the urban centers,

00:10:26.640 | and New York tended to be the highest numbers

00:10:28.920 | where it was lower in the Midwest.

00:10:31.120 | And so the hypothesis was potentially

00:10:33.260 | because it was a more rural setting,

00:10:34.640 | maybe there was pesticide exposure

00:10:36.040 | and that had led to these lower numbers.

00:10:37.520 | But another equally plausible explanation

00:10:40.240 | may be that sort of a different population,

00:10:43.620 | and maybe that could explain these differences.

00:10:47.380 | So I think it's very important.

00:10:50.240 | And I think one of the sort of lacking things in this

00:10:53.220 | is there's not really longitudinal data.

00:10:54.740 | One of the greatest things would be

00:10:56.500 | if we just started tracking semen quality around the country

00:10:59.800 | just like we do obesity, like, you know,

00:11:01.440 | NHANES, CDC's survey of health in the US,

00:11:06.320 | if we added semen quality onto that.

00:11:08.340 | That way you could really see, you know,

00:11:09.580 | how it varies around the country and, you know,

00:11:11.680 | sort of compare like to like to see over time

00:11:14.460 | if there's really this progression.

00:11:15.780 | You know, one of the only studies to do that in Denmark,

00:11:19.280 | they've started around, you know, around 2000

00:11:21.980 | and tracked semen quality among, you know,

00:11:24.680 | volunteers that came in when they were conscripted

00:11:26.640 | for military service in Denmark,

00:11:28.320 | they were offered the opportunity

00:11:29.480 | to participate in this study.

00:11:31.100 | And so some men did.

00:11:33.660 | And what they found is actually that semen quality

00:11:36.100 | was fairly uniform over about 20 years where they had data.

00:11:39.240 | But sort of another very interesting part of that study

00:11:41.600 | is that only about a quarter of those men

00:11:43.520 | had normal semen quality.

00:11:45.880 | So it was sort of very concerning.

00:11:47.460 | You know, it was, I guess, reassuring

00:11:48.840 | that it wasn't further declining,

00:11:50.640 | but very concerning that only a quarter of Danish men

00:11:53.000 | had, you know, normal semen quality.

00:11:54.620 | And they're one of the, I think,

00:11:56.020 | thought leaders in this field,

00:11:57.660 | just because it's sort of a reproductive crisis there.

00:12:00.500 | - You mentioned that some of this apparent decline

00:12:03.700 | in semen quality might be related to the fact

00:12:05.740 | that the tools to measure semen quality

00:12:07.520 | are getting better and better.

00:12:09.340 | And that would make sense if, for instance,

00:12:11.200 | one is just looking at total volume, morphology,

00:12:15.300 | which means shape, I should have clarified that,

00:12:19.020 | how many forwardly motile sperm there are,

00:12:21.500 | and then also adding in, you know, a very sensitive measure,

00:12:25.660 | such as DNA fragmentation.

00:12:28.520 | You know, essentially as the instruments get finer and finer,

00:12:31.400 | you discover more and more details.

00:12:33.140 | And if you are rating quality

00:12:36.020 | along a number of different dimensions,

00:12:38.000 | then it would make sense that those would tear out

00:12:40.260 | into different levels.

00:12:41.560 | So if one were to simply ask four couples

00:12:46.220 | who want to get pregnant,

00:12:48.160 | and assuming that egg quality is not the issue,

00:12:51.720 | what percentage of failures to achieve successful pregnancy

00:12:57.280 | are the consequence of deficient sperm,

00:13:00.640 | deficient in any way?

00:13:02.480 | And is that number increasing over time?

00:13:06.400 | - Yeah, so I think that's really key.

00:13:08.220 | I think when couples think about fertility,

00:13:10.240 | usually it's thought of as a female problem.

00:13:12.840 | And I think there's just historic reasons for that.

00:13:15.320 | You know, if you look at data in the US,

00:13:17.200 | when couples do seek care for fertility,

00:13:19.720 | the man has bypassed probably a third of the time,

00:13:22.200 | even though when you look at the reasons for infertility,

00:13:24.920 | man contributes probably half of the time to infertility.

00:13:28.400 | So I think there's a-- - Half.

00:13:29.640 | - Half, yeah.

00:13:30.800 | So I think there's a huge need

00:13:32.140 | just to understand and evaluate the man.

00:13:34.160 | And one of the reasons for this, I think,

00:13:35.900 | is that one of the main treatments for infertility

00:13:39.240 | in the US is IVF, which is very powerful.

00:13:42.320 | I think one of the greatest marvels of medicine

00:13:45.520 | in probably the last quarter century

00:13:48.360 | is our ability to mix a sperm and egg in a dish

00:13:50.680 | and create a life.

00:13:51.580 | It's really remarkable.

00:13:53.040 | But because it now takes just a single sperm

00:13:55.680 | through something called

00:13:56.520 | intracytoplasmic sperm injection,

00:13:58.000 | where you can inject one egg or one sperm into an egg,

00:14:01.440 | the bar has gone down dramatically.

00:14:03.680 | For couples just trying without any assistance,

00:14:06.800 | probably need 20 to 40 million moving sperm.

00:14:09.200 | But now with these remarkable techniques,

00:14:11.360 | you just need one sperm.

00:14:13.520 | And so because of that,

00:14:15.920 | I think a lot of our innovation and research

00:14:18.960 | on male fertility has probably gone to the wayside

00:14:21.040 | just because clinically,

00:14:22.880 | we just need a few dozen sperm for most couples.

00:14:26.220 | - What about testosterone levels?

00:14:28.560 | Are those also declining?

00:14:30.100 | We hear this.

00:14:31.140 | And when I look at the literature,

00:14:34.360 | I can find evidence for that.

00:14:36.540 | But the question is also whether or not

00:14:39.700 | the amount of decline in testosterone levels

00:14:41.960 | is significant in a way that impacts, let's say fertility,

00:14:45.440 | but also vitality in other ways,

00:14:48.600 | energy, mood, sexual health, et cetera.

00:14:52.800 | What's the story with testosterone levels?

00:14:54.340 | Are they indeed declining on average

00:14:57.680 | across the male population in the US and elsewhere?

00:15:00.680 | - I think there is pretty convincing evidence

00:15:02.560 | that that is happening.

00:15:03.580 | And I think the reason for that,

00:15:04.800 | again, is probably not certain,

00:15:06.160 | but there have been some pretty nicely designed

00:15:09.360 | cohort studies where they have recruited men

00:15:12.040 | in the 2000s, the 90s, the 80s.

00:15:15.160 | And you can see that depending on when these men

00:15:17.320 | are recruited, just matching age for age,

00:15:20.460 | these testosterone levels tend to be lower.

00:15:22.720 | And then NHANES, which is, again,

00:15:24.580 | this sort of longitudinal study run by the CDC,

00:15:27.100 | that has also shown,

00:15:29.760 | looking at testosterone levels over decades,

00:15:32.440 | the testosterone levels have declined over time.

00:15:35.240 | So chemical exposure is one possible explanation.

00:15:38.320 | Again, either in adult or adolescent life or in utero,

00:15:42.080 | but obesity I think is also sort of a convincing explanation

00:15:44.760 | is we're more sedentary, you know, we get bigger.

00:15:48.320 | That's one of the places that testosterone can decline.

00:15:50.360 | I think there's different sort of explanations for that.

00:15:53.720 | You know, as testosterone is produced,

00:15:55.320 | it's aromatized in peripheral tissue,

00:15:58.480 | you know, fatty tissue, fat has a lot of this aromatase,

00:16:01.040 | so that converts testosterone to estrogen.

00:16:03.260 | So it necessarily, you know, lowers the testosterone level

00:16:06.400 | that's circulating in our body.

00:16:08.080 | Also just insulating the testicles, our thighs get bigger.

00:16:11.880 | Insulating the testes can also sometimes lower

00:16:14.240 | the efficiency of production a little bit too.

00:16:16.040 | - Because of heat effects?

00:16:17.600 | - Because of heat effects.

00:16:19.120 | - Yeah, I was going to ask about this later,

00:16:20.800 | but I'll ask about it now,

00:16:21.640 | since we're talking about heat effects

00:16:22.880 | and sperm and testosterone,

00:16:25.020 | the heat of course being not good

00:16:28.520 | for sperm health and testosterone,

00:16:31.400 | which is, I've read a meta-analysis.

00:16:35.520 | I don't know how high quality it is,

00:16:39.380 | but that explained that there is some evidence

00:16:43.520 | for either heat effects

00:16:45.840 | or possibly non-heat related effects of cell phone,

00:16:50.660 | you know, smartphone in the pocket in pairing sperm health,

00:16:54.520 | maybe even testosterone levels.

00:16:56.780 | Now you hear this more often in kind of biohacky,

00:17:00.560 | I don't know, circles,

00:17:04.280 | which, you know, I'm not a fan of the word biohacking.

00:17:08.280 | It's not clear what it means,

00:17:09.680 | but it sounds like it means something

00:17:12.180 | about taking a shortcut using one thing

00:17:14.200 | for a purpose it wasn't intended.

00:17:15.880 | But, you know, it also makes sense to me

00:17:18.140 | that a smartphone could generate some heat,

00:17:21.140 | some radiation that might impair testicular function

00:17:24.720 | and therefore impair sperm quality

00:17:28.160 | and or testosterone levels.

00:17:30.600 | But is there any real solid data

00:17:33.720 | that carrying your cell phone in your pocket,

00:17:37.080 | let's assume on, that the cell phone is on,

00:17:39.280 | is bad for sperm health or testosterone levels?

00:17:42.380 | - Yeah, so I think there's not convincing evidence

00:17:45.400 | that it's going to help testosterone levels.

00:17:48.020 | I think that, you know--

00:17:48.860 | - It's going to hurt testosterone?

00:17:50.240 | - It's not going to hurt, yeah.

00:17:51.360 | So I should make clear that I think that

00:17:53.720 | in terms of production and heat effects,

00:17:55.840 | you know, sperm production is much more sensitive

00:17:57.680 | than testosterone production.

00:17:59.320 | But there have been some studies

00:18:00.500 | looking at cell phone exposure,

00:18:01.700 | because, again, you're getting this,

00:18:03.960 | whether it's heat, whether it's sort of the,

00:18:05.840 | you know, radio frequency, you know, waves coming in,

00:18:08.800 | I think you could posit sort of different explanations

00:18:11.400 | of why that may be harmful.

00:18:13.040 | So there have been some studies that, you know,

00:18:14.680 | looked early on, you know,

00:18:15.960 | men that use cell phones more or less,

00:18:18.160 | they had lower semen quality if they used it more.

00:18:21.100 | But you can also imagine there's huge differences

00:18:22.680 | in men that do and do not use cell phones.

00:18:24.480 | So, you know, it's a hard experiment to design,

00:18:28.020 | but there have been some studies doing this in vitro,

00:18:30.740 | so in the laboratory, so taking, you know,

00:18:33.420 | sperm in a cup, basically,

00:18:34.880 | and putting a cell phone next to it or not next to it

00:18:37.400 | to try and see if that played a role.

00:18:39.780 | There have been studies done

00:18:40.960 | where they sort of normalize the heat, you know,

00:18:44.160 | they kind of put it on sort of a special stage

00:18:46.480 | so that it's not heat necessarily,

00:18:47.820 | but maybe it's RF exposure.

00:18:49.040 | So those studies, I think, don't show

00:18:51.160 | sort of a clinically meaningful change,

00:18:54.520 | but there have been some studies that say

00:18:55.800 | that maybe DNA fragmentation of sperm

00:18:58.340 | can go up a little bit if there's close proximity

00:19:01.460 | to a cell phone.

00:19:02.540 | So I think, you know, when patients ask me that,

00:19:05.780 | which is a common question I get in the clinic,

00:19:07.240 | obviously patients are coming in,

00:19:08.840 | they want to do, you know, whatever they can

00:19:11.120 | to try and improve their chances.

00:19:12.860 | So I think generally, I think the data is not convincing,

00:19:16.820 | but, you know, if it's easy enough,

00:19:17.960 | certainly to be aware of it, you know,

00:19:19.400 | I think putting a laptop on a desk rather than in your lap,

00:19:22.240 | I think for heat exposure is probably the biggest thing

00:19:24.200 | that we want to minimize.

00:19:26.320 | About a year and a half ago, I did an episode

00:19:28.540 | about testosterone and estrogen,

00:19:31.140 | where it's manufactured in the male and female body,

00:19:32.940 | et cetera, and I found a very interesting graph

00:19:35.220 | in a textbook on behavioral endocrinology

00:19:38.980 | by a guy named Randy Nelson,

00:19:40.700 | who I happen to know through the field

00:19:43.000 | of behavioral endocrinology

00:19:44.560 | as it's typically studied in animals.

00:19:46.500 | So most of that book centers on animal studies,

00:19:48.820 | but there's a fraction of the studies

00:19:50.540 | that center on human data.

00:19:53.040 | And there was a very interesting graph

00:19:55.440 | that showed testosterone levels

00:19:57.160 | as a function of age in males.

00:19:59.260 | And as one might expect,

00:20:01.540 | testosterone levels were on average much higher

00:20:04.580 | in late teens, early 20s, 30s,

00:20:07.380 | and there was a progressive decline.

00:20:09.580 | But what was remarkable to me about that graph

00:20:11.840 | is that even when exploring the scatter plots,

00:20:16.300 | 'cause they showed individual points,

00:20:17.780 | they didn't just show the averages

00:20:19.900 | of testosterone levels in men in their 50s, 60s, 70s, 80s,

00:20:24.180 | even 90s, there were these outliers,

00:20:27.180 | these guys who had testosterone levels

00:20:29.300 | that were on par with testosterone levels

00:20:32.460 | of men in their 30s,

00:20:33.820 | but these guys were in their 50s, 60s, 70s, 80s, even 90s.

00:20:38.220 | So do you observe this clinically?

00:20:39.760 | Do you observe that men are coming in,

00:20:42.600 | who are older than 40 and have testosterone levels

00:20:46.180 | and presumably free testosterone levels as well

00:20:48.580 | that are still very high?

00:20:52.220 | The reason I asked is that I think we've all been told

00:20:54.180 | and we presume that testosterone levels decline with age,

00:20:56.860 | and one would expect some outliers.

00:20:58.460 | And of course, we don't know whether or not those guys

00:21:00.660 | in their 90s who have the testosterone levels

00:21:03.260 | that match the averages of men in their 30s

00:21:06.060 | didn't have even greater testosterone levels in their 30s,

00:21:08.580 | but given that they were sealing out

00:21:09.880 | around 900 nanograms per deciliter,

00:21:12.540 | toward the high-end normal, depending on the scale,

00:21:15.160 | already at age 90,

00:21:17.860 | it's kind of hard to imagine that earlier

00:21:19.300 | they're walking around with 2,000 nanogram

00:21:21.700 | per deciliter testosterone.

00:21:23.520 | So do you see this?

00:21:25.260 | Are there some, is there just a lot of natural variation

00:21:27.900 | in testosterone levels of men

00:21:29.540 | who walk into the clinic at any age?

00:21:31.460 | And of course, what is special about these individuals

00:21:34.860 | that are maintaining high normal testosterone levels

00:21:39.540 | into their later years?

00:21:42.080 | - Yeah, that's a great question.

00:21:42.920 | I think this is such a common question.

00:21:44.660 | Anytime we talk about testosterone,

00:21:46.180 | I think anytime we talk about most sort of clinical tests

00:21:49.820 | that we do, what is average, what is normal?

00:21:52.800 | So we do see great variation.

00:21:54.180 | I mean, I think just like you're saying,

00:21:55.760 | I usually let everybody know

00:21:56.980 | that usually testosterone peaks kind of early 20s,

00:22:00.940 | and it tends to go down probably 1% a year forever.

00:22:04.360 | But there are people that have very, very high levels.

00:22:07.980 | Just mirroring that graph that you described,

00:22:10.580 | I certainly have patients,

00:22:12.300 | we screen for testosterone levels

00:22:14.500 | when patients come in with complaints

00:22:15.900 | where we're worried about that,

00:22:17.480 | low energy level, low libido,

00:22:19.420 | some of the symptoms of low testosterone, sexual dysfunction.

00:22:22.860 | And to my surprise, sometimes these men,

00:22:26.080 | I've seen 80-year-olds

00:22:27.140 | that certainly have the highest testosterone level I'll see

00:22:29.660 | for six months.

00:22:30.600 | Why that is, I think is not certain.

00:22:33.220 | Maybe it has to do with everything.

00:22:36.900 | There's probably sort of a bell-shaped curve,

00:22:38.220 | and everybody's a little bit different.

00:22:40.140 | But androgen sensitivity, sensitivity of the receptor,

00:22:43.420 | they make it more efficiently.

00:22:44.840 | But I have not really noticed,

00:22:46.340 | again, 'cause at least in clinical practice,

00:22:49.580 | when patients come in, they come in with a complaint.

00:22:51.740 | And so even men with very high levels,

00:22:54.760 | they may have some of the same dysfunction

00:22:56.260 | in men with low levels.

00:22:57.100 | So I think with low levels, you can try and treat that,

00:22:59.460 | and that may be the solution.

00:23:01.140 | But for men with these, what we would consider high levels,

00:23:05.560 | there may be other issues going on.

00:23:07.300 | - Let me frame the question

00:23:09.740 | I was going to ask a little bit differently.

00:23:11.900 | When someone comes into your clinic

00:23:13.560 | and you measure their testosterone levels,

00:23:15.580 | as you mentioned, they're likely coming in

00:23:17.200 | because they have some issue.

00:23:19.140 | Prostate issue, sexual function issue, et cetera.

00:23:21.640 | But you do get a read on their sort of crude morphology

00:23:28.020 | of their body, right?

00:23:29.520 | So you could visibly determine whether or not

00:23:31.540 | they're likely to be obese or not, regardless of age.

00:23:36.400 | So earlier you mentioned obesity as a risk factor

00:23:38.880 | for lowering testosterone and sperm quality.

00:23:42.040 | You mentioned that fat aromatizes testosterone

00:23:44.520 | into estrogen, so that's at least one mechanism.

00:23:46.660 | I wish that could happen.

00:23:48.040 | But if you were to just step back and say,

00:23:50.200 | okay, if somebody who walks into my clinic tends to be,

00:23:55.200 | let's say, healthier looking, you know, not obese,

00:23:58.500 | let's just put the cutoff

00:23:59.500 | at what you would presume is obese,

00:24:01.580 | is there a higher probability that their testosterone levels

00:24:05.920 | are going to be within normal range?

00:24:08.000 | Conversely, when somebody walks in and they're obese,

00:24:11.500 | do you fully expect their testosterone levels

00:24:13.360 | to be subnormal?

00:24:14.500 | Or are you sometimes seeing obese people walking in

00:24:18.600 | with high testosterone?

00:24:20.800 | And the reason I'm asking this is not to create confusion,

00:24:23.320 | is that I think that everybody out there

00:24:25.960 | who's thinking about sperm quality and testosterone levels

00:24:29.600 | and this apparent decline, trying to figure out,

00:24:32.400 | you know, okay, what can we do in order to maintain

00:24:36.500 | the health metrics that are going to, of course,

00:24:38.280 | increase fertility, but for those that don't want

00:24:39.880 | to have kids or who already have kids

00:24:41.280 | are going to at least maintain or improve vitality,

00:24:45.000 | is obesity really the thing to avoid?

00:24:48.140 | So is there a, not one for one,

00:24:50.080 | but is there a tight correlation

00:24:51.640 | between obesity and testosterone levels?

00:24:54.200 | - I would say that you cannot predict.

00:24:55.960 | I think that sort of would be the take home.

00:24:57.700 | And so I think that, you know,

00:24:58.900 | more information is always better.

00:25:00.360 | You know, when I see patients in clinic,

00:25:03.320 | you know, some patients are walking around, you know,

00:25:05.800 | with, yeah, everything is totally normal

00:25:07.760 | and they're very healthy,

00:25:08.720 | all the numbers come in at the normal range,

00:25:10.500 | but sometimes when men, you know, look totally normal,

00:25:13.640 | they talked about taking care of their life,

00:25:15.220 | they exercise, you know, five, seven days a week,

00:25:17.920 | their testosterone levels can be very low.

00:25:19.480 | So even despite, you know, having what we would consider

00:25:22.920 | should really give them, you know, symptoms,

00:25:27.120 | they're able to compensate, you know,

00:25:28.520 | maybe they've lived their whole life

00:25:29.680 | and that they don't know what normal is.

00:25:31.440 | Now we get them, you know, to sort of normal levels,

00:25:33.600 | a lot of times they feel better, again,

00:25:34.980 | because they had no idea how they should feel.

00:25:37.560 | But I think that that's just sort of important

00:25:39.160 | that everybody, you know, should be screened.

00:25:41.020 | I think that, you know, testosterone, semen quality,

00:25:44.160 | there have been shown to even be barometers of health.

00:25:47.120 | So, you know, men with lower testosterone levels

00:25:49.100 | have higher risk of, you know, heart disease,

00:25:50.980 | diabetes, mortality, the same studies exist

00:25:54.140 | for semen quality as well.

00:25:55.980 | And, you know, again, they may have sort of

00:25:57.640 | a similar relationship and explanation why that may be,

00:26:00.620 | but I think it's hard to just predict, you know,

00:26:03.100 | based on appearance, what, you know, testosterone will be,

00:26:06.920 | what semen quality will be, what testicular function will be

00:26:08.940 | without actually getting some objective data.

00:26:11.140 | And actually, if you look at the trend of semen quality

00:26:14.380 | decline over time, kind of getting back

00:26:16.060 | to some of those earlier points you were making,

00:26:18.460 | if you were to overlay that on the known association

00:26:21.020 | between obesity, its effects on semen quality,

00:26:25.400 | that actually doesn't explain the whole decline.

00:26:27.260 | 'Cause the, you know, the purported decline

00:26:30.140 | in semen quality is about 50%.

00:26:31.800 | But if you just, if you were to say, well,

00:26:34.100 | what would we expect if, you know, we look at, you know,

00:26:36.500 | 'cause we were able to track exactly how much fatter

00:26:38.380 | we are now than we used to be,

00:26:40.740 | that actually only explains about a 10% decline.

00:26:42.900 | So I think there is, you know, to your point,

00:26:44.420 | something more, and it is not something

00:26:46.740 | that you can just identify by eye.

00:26:48.380 | - What are the do's and don'ts as it relates to,

00:26:54.020 | I don't want to use the word optimizing.

00:26:55.660 | It's gotten me into trouble before because the word optimize

00:26:59.080 | or optimal suggests that there's a perfect number

00:27:01.440 | that one should all attain if possible.

00:27:04.620 | But in reality, optimal is a day-to-day thing, at least.

00:27:09.360 | But what should people avoid in order to get

00:27:14.260 | their sperm quality as high as possible,

00:27:16.980 | their testosterone level?

00:27:19.020 | Again, here, I have to be careful.

00:27:20.180 | I don't want to say as high as possible

00:27:21.440 | because some people might not want excessive androgen,

00:27:25.360 | but at the high end of normal,

00:27:27.420 | perhaps would be the ideal for many people.

00:27:30.360 | What should people do?

00:27:33.120 | What should they avoid?

00:27:34.760 | And here I'm setting aside any prescription

00:27:37.940 | clinical treatments that, such as testosterone injections

00:27:41.540 | or things like a chorionic gonadotrop,

00:27:43.840 | human chorionic gonadotropin,

00:27:45.180 | things that we can talk about a little bit later,

00:27:46.520 | but what should every male be doing

00:27:47.960 | in order to optimize these health parameters?

00:27:50.980 | - Yeah, so I think that there are some risk factors

00:27:52.840 | that we do, like we'll start with semen quality.

00:27:54.620 | So we talked about heat, I think that's a big one.

00:27:57.120 | So like hot tub saunas, trying to avoid those,

00:27:59.840 | some light data on sea warmers.

00:28:01.820 | Anytime we kind of get this external heat source

00:28:04.660 | to the scrotum, the testicles are outside the body

00:28:06.900 | 'cause they need to be a little cooler.

00:28:08.200 | So anything that warms them up can certainly be a problem.

00:28:10.940 | - Could I just briefly interrupt there to ask,

00:28:13.840 | we've done episodes on sauna

00:28:16.020 | and some of the health benefits of sauna.

00:28:18.620 | Is it sufficient for somebody to bring in a cold pack

00:28:21.540 | to the sauna and put that up in their groin?

00:28:23.600 | I actually have suggested that.

00:28:25.780 | That's actually what I do when I go into the sauna.

00:28:29.300 | And I have suggested this on podcasts,

00:28:31.980 | not just for people who are trying to conceive,

00:28:33.480 | because it seems like heat, as you mentioned,

00:28:35.780 | is bad for sperm, not quite as bad for testosterone levels,

00:28:40.500 | but is it also true that heating the testicle too much

00:28:44.820 | is generally bad for endocrine function in males

00:28:47.960 | and therefore if one is going to go into a hot sauna

00:28:50.940 | for 20 minutes or more to essentially cool the scrotal area?

00:28:57.340 | - Yeah, I mean, I think the spermatogenesis

00:28:59.380 | or sperm production is certainly a lot more sensitive.

00:29:01.860 | Whether you can sort of thwart the effects

00:29:04.140 | of external heat with a cooling pack,

00:29:05.740 | I think it makes sense.

00:29:06.700 | There are studies that have looked at different ways

00:29:08.840 | to cool the scrotum and have compared

00:29:10.980 | semen quality before and after,

00:29:12.340 | and there's some data that may help.

00:29:14.140 | It just depends how long you're gonna spend in the sauna

00:29:17.060 | and how cold that pack is gonna remain.

00:29:19.300 | - So ice pack and in the sauna for 20 to 45 minutes.

00:29:23.900 | - And is the ice pack still cold afterwards?

00:29:25.740 | - Yeah, they actually sell, and by the way,

00:29:28.120 | I have no relationship to any of these companies,

00:29:29.620 | but they actually sell cold packs that are designed

00:29:31.900 | to be worn in your shorts.

00:29:33.260 | So if you go to a, you know,

00:29:35.160 | I'll go to a Russian banya every once in a while now,

00:29:37.060 | I guess I'm outing myself.

00:29:38.180 | Yes, I have a cold pack in my shorts

00:29:40.540 | when I go to the Russian banya.

00:29:42.040 | But they have a sort of an insulation

00:29:47.240 | so that the very cold surface is cold enough,

00:29:50.960 | but it's not right up in contact with the scrotal skin

00:29:53.620 | because that could get, I wanna make a bad joke

00:29:56.740 | and say it could get sticky, that situation.

00:29:58.920 | You don't want it being so cold

00:30:00.460 | that it actually would stick to the skin

00:30:02.380 | and then it could potentially damage the skin

00:30:04.300 | when you try and remove the cold pack.

00:30:05.500 | So it has a thin insulating layer

00:30:07.340 | and yeah, that's essentially what it is.

00:30:12.320 | - Yeah, I mean, frostbite to the scrotum is not theoretical.

00:30:14.460 | It could certainly happen, so you do wanna be careful.

00:30:16.580 | So I mean, in theory, that should be adequate

00:30:19.200 | to sort of, you know, to decrease the risk

00:30:20.940 | of that particular effect.

00:30:23.220 | You know, I keep coming back to health,

00:30:24.500 | how important that is to maintain, you know,

00:30:27.740 | adequate sperm production

00:30:28.900 | because I think these two are very linked.

00:30:30.860 | You know, there have been studies that show

00:30:31.980 | that men with more comorbid conditions,

00:30:34.300 | so obesity, hypertension, hyperlipidemia,

00:30:36.340 | as these sort of stack up,

00:30:37.740 | we see a decline in testicular function,

00:30:39.940 | so lower testosterone levels and lower sperm quality.

00:30:42.900 | So I think, you know, taking ownership of your health,

00:30:46.440 | I think is important as well.

00:30:48.420 | You know, a lot of times,

00:30:49.620 | fertility tends to be one of the first touch points

00:30:52.820 | that some men have with healthcare, you know,

00:30:55.380 | because generally what brings men to the doctor,

00:30:57.420 | it's usually pain or, you know, kind of a problem.

00:31:00.420 | So, you know, if men are in their 20s and 30s

00:31:02.420 | getting ready to start a family or 40s in some cases,

00:31:04.780 | sometimes they haven't seen a primary care doctor.

00:31:07.100 | So some of these things,

00:31:08.020 | some of this relationship has not been established yet.

00:31:10.460 | So I think, you know, thinking about ways to start that,

00:31:12.320 | I think would be important too.

00:31:14.460 | And then I know you don't wanna talk about testosterone,

00:31:16.460 | but testosterone is actually a fairly common problem

00:31:18.900 | that we see in fertility clinics.

00:31:21.740 | I would say that estimates say maybe about one in 20

00:31:24.780 | in fertile men are that way because of testosterone.

00:31:27.740 | So I think when, you know,

00:31:29.180 | people get testosterone in different places

00:31:30.940 | and hopefully, you know,

00:31:31.760 | whatever provider you're getting it from

00:31:34.220 | tells you that one of the side effects of this

00:31:37.220 | is lower sperm production.

00:31:38.340 | It's actually been tested as a contraceptive

00:31:39.980 | and, you know, with some other agents,

00:31:41.740 | it can actually be fairly effective.

00:31:43.060 | So we just wanna make sure that, you know,

00:31:45.380 | if men are starting testosterone,

00:31:47.120 | they're doing it for the right reasons

00:31:48.300 | and they're doing it safely.

00:31:49.220 | - I think about testosterone replacement therapy,

00:31:52.120 | although as we were talking about

00:31:53.220 | before we started recording,

00:31:54.300 | I am really on a push now to rename what people call TRT,

00:31:59.300 | testosterone replacement therapy,

00:32:02.120 | because indeed some people have low testosterone

00:32:04.060 | and need it replaced, the R in TRT.

00:32:06.580 | But I think what you're referring to, if I'm not mistaken,

00:32:09.900 | is that there are probably millions of young men

00:32:14.900 | and older men taking exogenous testosterone

00:32:18.980 | injections, creams, pills, pellets, you know,

00:32:22.060 | any number of nasal sprays now, you know,

00:32:23.740 | any number of different routes of delivery

00:32:25.820 | of exogenous testosterone.

00:32:28.740 | And that dramatically reduces

00:32:32.500 | one's endogenous testosterone production

00:32:35.300 | and dramatically reduces one's sperm count

00:32:37.940 | and maybe even quality.

00:32:39.180 | We'll maybe talk about this a little bit later,

00:32:40.700 | but maybe even can, there's,

00:32:42.620 | I've been told that it can perhaps introduce

00:32:45.300 | a DNA fragmentation within the remaining viable sperm

00:32:49.340 | as well.

00:32:50.160 | So do I have that correct?

00:32:51.220 | You're saying that you see one in 20 men

00:32:53.700 | have issues with fertility

00:32:54.960 | because they are taking testosterone.

00:32:57.380 | So their testosterone levels presumably

00:32:58.940 | are going to be high end normal or more,

00:33:00.820 | but they are doing presumably

00:33:02.660 | not testosterone replacement therapy,

00:33:04.400 | but they're doing what I call

00:33:05.540 | testosterone augmentation therapy,

00:33:07.300 | meaning they were somewhere in the 300 to 900 nanograms

00:33:10.020 | per deciliter range,

00:33:12.100 | but decided to start taking testosterone anyway.

00:33:15.240 | And then their sperm count essentially diminishes to nil

00:33:21.340 | or close to it.

00:33:23.260 | - In some cases, yeah.

00:33:24.540 | So, I mean, I think there's various reasons

00:33:26.340 | that you would take testosterone.

00:33:27.340 | I think, you know, some people have been treated,

00:33:30.100 | you know, years ago,

00:33:31.540 | and so they do need to replace testosterone, you know,

00:33:34.340 | but some people do it for augmentation.

00:33:35.660 | I just usually say testosterone therapy just so it's correct.

00:33:38.160 | - You kill the R, I like that.

00:33:39.500 | That's better than the TAT,

00:33:41.120 | which doesn't help very good.

00:33:42.020 | - Okay, just testosterone therapy.

00:33:44.140 | - Yeah. - Okay.

00:33:44.980 | - But if you had, you know, for example,

00:33:46.900 | we take a hundred of my infertile patients

00:33:48.900 | that come in to see me in clinic,

00:33:50.400 | at least five of those men will be infertile

00:33:52.740 | because they're on testosterone therapy.

00:33:54.820 | And some of them do have that suspicion.

00:33:57.000 | They say, you know, I'm gonna level with you.

00:33:58.660 | This is why my levels are probably low.

00:34:01.020 | But a lot of men were not told that, you know,

00:34:02.700 | when they started therapy.

00:34:03.540 | So I think certainly for reproductive age men,

00:34:05.380 | that's a very important conversation to have

00:34:08.120 | because there can be some other, you know,

00:34:10.260 | ways that we kind of maintain sperm production.

00:34:12.340 | I think sperm cryopreservation is a good option

00:34:14.420 | for these men as well.

00:34:15.680 | Or there may be other therapies they can think about

00:34:18.780 | just because of reproductive toxicity.

00:34:21.140 | - What about HCG, human chorionic gonadotropin?

00:34:24.580 | I hear about a lot of people who go on testosterone therapy

00:34:26.820 | who take HCG every other day or so.

00:34:30.140 | Typically the dosages that I hear about

00:34:32.980 | because people write to me about this stuff all the time.

00:34:35.060 | Really, it's one of the most commonly asked questions.

00:34:38.260 | I get many questions about many topics,

00:34:39.860 | but I would say a full 10 to 20% of them

00:34:44.860 | are about penises or testosterone.

00:34:48.940 | - Those are perfect though.

00:34:51.340 | - Right, exactly.

00:34:52.820 | So a number of those guys who are taking testosterone

00:34:57.820 | will be prescribed HCG to stimulate sperm production,

00:35:02.560 | endogenous sperm production to maintain healthy sperm,

00:35:06.780 | presumably because they either want to conceive

00:35:08.520 | or intending to conceive in the future.

00:35:10.440 | Is that the best line of treatment for maintaining fertility

00:35:13.500 | while people are taking testosterone therapy?

00:35:15.660 | - Yeah, that's one of the therapies that we use

00:35:17.200 | and I think it can work well.

00:35:18.240 | Just a low dose usually, and for those that know,

00:35:21.680 | 500 to 1,000 units every other day is usually adequate.

00:35:25.600 | - As we all know, quality nutrition influences,

00:35:29.260 | of course, our physical health,

00:35:30.420 | but also our mental health and our cognitive functioning,

00:35:33.140 | our memory, our ability to learn new things and to focus.

00:35:36.060 | And we know that one of the most important features

00:35:38.240 | of high quality nutrition is making sure

00:35:40.180 | that we get enough vitamins and minerals

00:35:42.180 | from high quality unprocessed or minimally processed sources

00:35:45.800 | as well as enough probiotics and prebiotics and fiber

00:35:48.900 | to support basically all the cellular functions in our body,

00:35:51.960 | including the gut microbiome.

00:35:53.820 | Now, I, like most everybody,

00:35:55.940 | try to get optimal nutrition from whole foods,

00:35:59.000 | ideally, mostly from minimally processed

00:36:01.740 | or non-processed foods.

00:36:03.180 | However, one of the challenges

00:36:04.300 | that I and so many other people face

00:36:06.140 | is getting enough servings of high quality fruits

00:36:08.200 | and vegetables per day, as well as fiber and probiotics

00:36:11.160 | that often accompany those fruits and vegetables.

00:36:13.360 | That's why way back in 2012,

00:36:15.400 | long before I ever had a podcast, I started drinking AG1.

00:36:19.240 | And so I'm delighted that AG1

00:36:20.840 | is sponsoring the Huberman Lab podcast.

00:36:23.000 | The reason I started taking AG1

00:36:24.740 | and the reason I still drink AG1 once or twice a day

00:36:28.040 | is that it provides all of my foundational nutritional needs.

00:36:30.820 | That is, it provides insurance that I get the proper amounts

00:36:34.360 | of those vitamins, minerals, probiotics, and fiber

00:36:37.180 | to ensure optimal mental health,

00:36:39.240 | physical health, and performance.

00:36:41.400 | If you'd like to try AG1,

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00:36:57.080 | So if somebody is not taking testosterone exogenously,

00:37:01.760 | they gotten their body fat level down

00:37:04.880 | to a point where they're not considered obese.

00:37:06.880 | So they're hopefully doing some cardiovascular exercise

00:37:09.580 | each week, maybe doing some sport

00:37:11.360 | or some resistance training too

00:37:13.100 | with the intention of maintaining all around good health.

00:37:17.400 | Stave off, you know, cerebrovascular, cardiovascular issues.

00:37:22.080 | What are some of the other don'ts?

00:37:23.880 | I'm going to assume that smoking cigarettes

00:37:26.520 | or vaping cigarettes is bad.

00:37:28.600 | There are any studies that look specifically

00:37:30.180 | at vaping and sperm quality or testosterone levels.

00:37:33.240 | And is there any evidence that smoking cigarettes

00:37:37.140 | is good for testosterone levels or sperm production?

00:37:39.320 | 'Cause I'm guessing the answer is no.

00:37:40.540 | I feel like nowadays we just say don't smoke,

00:37:43.200 | but the data are the data.

00:37:45.080 | Who knows, maybe nicotine can help sperm.

00:37:46.800 | I have no idea.

00:37:47.800 | - Right, it's possible.

00:37:49.620 | I don't think we have the data on that yet,

00:37:51.160 | but yeah, I mean, I think like to your point,

00:37:53.000 | I think lifestyle factors are certainly a big one.

00:37:55.060 | And you know, some of these, you know,

00:37:56.680 | potentially, you know, kind of unhealthy habits.

00:37:59.900 | So smoking is certainly something you should not do.

00:38:01.880 | There have been, you know, lots of studies

00:38:03.280 | that do link that to, you know, lower quality.

00:38:05.960 | Again, all the different measures that we look at.

00:38:08.340 | Also looking at fertility,

00:38:09.400 | these men tend to have a longer time to get pregnant.

00:38:12.400 | Alcohol, I think is another very common question

00:38:14.640 | that we get asked as well.

00:38:15.600 | And I think for that, there's, you know,

00:38:17.440 | I think less of a strong association that we've seen.

00:38:20.800 | So there, you know, there have been some studies

00:38:23.680 | that show that very high levels of alcohol,

00:38:25.360 | and I guess that's sort of subjective

00:38:26.600 | what some would consider higher or not.

00:38:29.480 | But you know, when you get above maybe 20 drinks a week,

00:38:32.280 | there have been some effects.

00:38:33.780 | But usually- - That's a lot of drinking.

00:38:35.660 | - I would think that's a lot.

00:38:36.500 | Yeah, but some people don't, but yeah.

00:38:38.760 | - I did an episode on alcohol.

00:38:39.960 | I think anything more than two,

00:38:41.560 | I know people are going to, you know, balk at this,

00:38:44.200 | but you know, I think any more than two drinks per week

00:38:46.500 | is where you start to see some negative effects

00:38:48.720 | on some health parameters.

00:38:50.000 | But you know, I'm not a detotaller, so yeah.

00:38:53.040 | - Yeah, but when you get to this 20 drink,

00:38:56.300 | that's when we started to see some effects on semen quality.

00:38:59.040 | But you know, the thing about that is that usually

00:39:01.080 | if these men are drinking 20,

00:39:02.400 | they're doing other things too, smoking,

00:39:04.000 | there can be other drug use as well.

00:39:05.820 | So it's hard to tease that out, but in general,

00:39:08.120 | that's, you know, I think certainly anything in moderation

00:39:10.940 | is probably, you know, is probably better.

00:39:13.200 | And so that's how I counsel patients.

00:39:15.460 | I think, again, it's very rare that I see men

00:39:17.440 | that are at that level,

00:39:18.280 | but I certainly let them know when I do.

00:39:20.140 | There's some new data coming out of,

00:39:23.200 | that we've started to work on looking at

00:39:25.120 | if there are different sensitivities to alcohol.

00:39:27.180 | So, you know, some East Asians have a mutation

00:39:29.600 | that leads to flushing.

00:39:31.220 | And so that may put those men at higher risk.

00:39:34.380 | When they mix alcohol, we may see some, you know,

00:39:37.340 | slightly lower sperm parameters.

00:39:39.680 | - You mean skin flushing

00:39:40.520 | because they don't make alcohol dehydrogenase?

00:39:42.660 | - Exactly, yeah. - Is that the idea, yeah.

00:39:44.600 | And is it, I've heard about that in Asian cultures,

00:39:47.500 | is there, in Asian population, excuse me,

00:39:50.500 | but is there any evidence that other populations

00:39:53.980 | might have slight variants on alcohol dehydrogenase

00:39:56.980 | that perhaps, maybe they don't lack it altogether,

00:39:59.620 | but they have, I don't know,

00:40:02.100 | there are hypomorphs for whatever gene

00:40:04.740 | makes alcohol dehydrogenase,

00:40:06.420 | and therefore they don't metabolize it as well,

00:40:08.500 | and therefore the toxic form of alcohol

00:40:10.980 | is active in their system longer.

00:40:12.820 | Is there any evidence for that?

00:40:14.220 | - No, I think that you're exactly right.

00:40:15.380 | I mean, I think the one that we think about

00:40:16.780 | is East Asian cultures, where it can be,

00:40:19.020 | you know, depending on, you know, the region,

00:40:20.420 | like Chinese, Taiwanese, probably about 40 to 50%

00:40:26.060 | of the population has, you know,

00:40:27.620 | mutation in the ALDH2 gene,

00:40:29.620 | but other populations and people with African ancestry,

00:40:34.020 | there's a rate of mutation, I think,

00:40:36.700 | I'm not gonna remember the exact percentage,

00:40:38.420 | but I think a few percentage points is some individual

00:40:42.260 | with Hispanic ancestry, Ashkenazi Jewish ancestry.

00:40:45.280 | So in this particular gene, there's a mutation,

00:40:48.300 | not the same one that East Asians have,

00:40:49.880 | but, you know, again, I think it gets to why a mutation,

00:40:52.880 | you know, where we see sort of negative effects

00:40:54.460 | would persist and the hypothesis that, you know,

00:40:57.420 | millennia ago, pretend potentially, you know,

00:40:59.980 | gave some sort of benefit for maybe an infectious disease

00:41:02.580 | or something similar to cystic fibrosis.

00:41:04.540 | Why, you know, again, this mutation would persist

00:41:06.620 | in our population if there's not, you know,

00:41:09.140 | some sort of advantage to those carrying it.

00:41:12.300 | But we do see another, you know, other men as well.

00:41:14.700 | So I think if, you know, it's a simple question,

00:41:17.080 | do you flush?

00:41:17.920 | If you flush, then maybe alcohol may have, you know,

00:41:20.200 | more of a harm than someone else.

00:41:23.380 | And then, you know, I get sort of getting along the lines.

00:41:25.420 | I think drug use is also something that we should try

00:41:27.420 | and, you know, we do counsel patients about

00:41:29.820 | 'cause that can also negatively affect semen quality.

00:41:32.300 | - Do you think it's fair to say that, okay,

00:41:34.240 | moderation is best, but if somebody had the option

00:41:37.780 | to either not drink or drink in moderation

00:41:41.260 | that they should not drink, would that be even better?

00:41:44.660 | Is there any evidence for that?

00:41:45.900 | I mean, it seems like nowadays we take the stance

00:41:48.540 | that not smoking at all is better

00:41:51.260 | than smoking a little bit.

00:41:52.380 | - Actually, when I was a postdoc at Stanford from 2005,

00:41:57.180 | yes, 2005 to end of 2010,

00:41:59.940 | you could still smoke on the Stanford campus.

00:42:01.760 | I'm not a smoker, but there was this collection of,

00:42:04.440 | I have to be careful what I say here.

00:42:05.820 | There was a particular group on campus of postdocs

00:42:08.980 | and graduate students that would, you know,

00:42:11.120 | that would colonize this little area outside the hospital

00:42:13.220 | and smoke because that's where you could smoke.

00:42:14.820 | That was eventually eliminated as a possibility.

00:42:18.060 | You can't smoke on Stanford campus as far as I know,

00:42:20.300 | but they would smoke right outside the hospital.

00:42:21.660 | Actually, a lot of the hospital workers would, you know,

00:42:23.660 | take a cigarette on their break.

00:42:24.760 | This is very common. - The irony, yeah, exactly.

00:42:26.500 | - Yeah, and this was common all over the country, right?

00:42:28.500 | This isn't unique to Stanford,

00:42:29.580 | but nowadays you just don't see that

00:42:31.380 | because it's not allowed.

00:42:33.580 | And we here don't smoke.

00:42:36.840 | It's terrible for XYZ and everything,

00:42:39.500 | every other letter of the alphabet.

00:42:41.480 | With alcohol, we tend to hear that if you're going to drink,

00:42:45.860 | drink in moderation.

00:42:46.980 | It's not clear exactly what number that is,

00:42:49.880 | but is it possible that zero alcohol

00:42:52.060 | is better for sperm and endocrine health than any alcohol?

00:42:56.540 | Or is that not a fair assumption?

00:42:59.220 | - I mean, I think that's a good question.

00:43:00.440 | I think, you know, your point about tobacco

00:43:03.340 | is an excellent one 'cause I think any smoking is bad.

00:43:06.660 | But alcohol, I think we don't have that data for yet.

00:43:09.140 | And so I think it's harder for me

00:43:11.540 | to make that recommendation to patients,

00:43:12.900 | especially because, you know,

00:43:14.060 | people do it for different reasons.

00:43:15.500 | And if it's not necessarily going to help them,

00:43:17.940 | you know, it'll harm them in social situations

00:43:19.680 | or other things.

00:43:20.620 | Yeah, I usually just, I usually give the moderation one,

00:43:24.020 | unless again, for the very high drinkers,

00:43:26.100 | I definitely talk about that.

00:43:28.180 | - You mentioned other drug use.

00:43:30.080 | I'm going to assume that unless prescribed

00:43:33.420 | for sort of post-surgical pain or something like that,

00:43:35.840 | that benzodiazepines, heroin, opioids of any kind,

00:43:40.840 | are just bad for sperm and testosterone.

00:43:44.540 | I think we could probably make that a short discussion.

00:43:47.020 | Right? - Yeah.

00:43:48.020 | - You know, I can't imagine any of that would be good

00:43:51.380 | for reproductive health.

00:43:52.960 | - Yeah, that's true.

00:43:53.800 | I mean, there's, again, you'd imagine, or maybe not,

00:43:56.460 | but there's not a lot of data on it.

00:43:58.700 | It'd be difficult to enroll or maybe easy to enroll,

00:44:01.180 | but a lot of those studies have not been done.

00:44:03.700 | But there's limited ones of, you know,

00:44:05.260 | people in rehab where they have shown, you know,

00:44:07.900 | these associations with, you know,

00:44:09.380 | addicts or users and lower quality.

00:44:11.640 | So yeah, that's how we talk to patients.

00:44:15.200 | - What about cannabis?

00:44:16.140 | I did an episode of this podcast about cannabis

00:44:18.000 | and I did highlight some of the medical applications

00:44:20.740 | of cannabis.

00:44:21.660 | I also highlighted that very high THC cannabis

00:44:24.300 | may predispose especially young males

00:44:27.380 | to later psychotic episodes.

00:44:29.260 | There are more and more data coming out

00:44:30.420 | about that all the time.

00:44:31.460 | I got a lot of flack for saying that,

00:44:34.420 | but that's my take on the data.

00:44:36.300 | And I know a lot of people use cannabis recreationally

00:44:41.740 | and in a kind of pseudo therapeutic way.

00:44:45.620 | I say pseudo therapeutic because I think a lot of people

00:44:48.420 | use cannabis to manage their anxiety

00:44:51.680 | and as an alternative to alcohol for a number of reasons.

00:44:56.580 | What is the relationship between cannabis use

00:45:00.180 | and testosterone and sperm production?

00:45:02.460 | Or I should say sperm quality, excuse me.

00:45:04.940 | - Yeah, so this is also a very common question.

00:45:07.620 | Again, with this wave of legalization across the country,

00:45:09.740 | I think more and more men and women are exposed to it.

00:45:13.660 | So again, there's data that even more men are exposed

00:45:18.660 | to it can lead to some harm in terms of sperm morphology

00:45:22.760 | and sperm numbers as well.

00:45:25.140 | One of the sort of landmark studies was about 1200 men

00:45:28.480 | and it found that men that use cannabis daily

00:45:30.820 | had significantly lower concentration, motility, morphology

00:45:34.120 | compared to those that didn't use it.

00:45:36.740 | So I think that's generally how men are counseled,

00:45:40.360 | but there's also other data that shows really a null effect.

00:45:43.740 | And I think that it goes into probably the composition,

00:45:46.640 | how men are taking it, the frequency,

00:45:48.700 | because a lot of that data is not well teased out

00:45:50.760 | in a lot of these studies.

00:45:52.060 | So I think I sometimes struggle with this with patients

00:45:56.700 | because some of them are taking it for some what they

00:46:01.320 | consider legitimate reasons, anxiety, sleep, pain.

00:46:04.400 | And if there's not sort of very convincing evidence

00:46:07.400 | that it's going to help and they're taking it maybe lower

00:46:11.100 | than the threshold where I know that there's good data

00:46:13.080 | that'll cause harm.

00:46:14.840 | I guess I try and be sort of honest about where we are,

00:46:17.840 | but I think with a lot of things related to sperm,

00:46:20.240 | I think our level of evidence is not great.

00:46:23.120 | - Are there any common over-the-counter medications

00:46:25.620 | that can negatively impact sperm quality and/or testosterone?

00:46:29.920 | Things like non-steroid anti-inflammatory,

00:46:33.740 | drugs, Tylenol, Advil type stuff, ibuprofen, acetaminophen,

00:46:38.520 | things of that sort that I and others might not be aware of.

00:46:43.620 | I'm not probing for anything in particular here.

00:46:45.520 | I just, I know that a lot of over-the-counter drugs

00:46:49.200 | have effects that we're just simply not aware of.

00:46:52.620 | - Yeah, I mean, I think we probably need more data,

00:46:54.420 | but I think currently we think all of those are safe.

00:46:57.120 | - I'm curious about the pituitary gland,

00:47:00.000 | as many listeners of this podcast already know

00:47:02.840 | is a gland that receives signals from the brain.

00:47:06.500 | The gland sits near the roof of the mouth.

00:47:09.100 | I think that's fair.

00:47:11.460 | And releases critical hormones into the bloodstream

00:47:14.820 | that control the output of testosterone from the testes

00:47:18.120 | as well as output of hormones from other glands.

00:47:20.960 | I know a number of people end up playing sports

00:47:25.100 | like football or rugby or even lacrosse or even soccer.

00:47:30.100 | I've read there are data on this.

00:47:32.520 | They're heading the soccer ball quite a lot

00:47:34.840 | or martial arts, or they get a head injury at some point.

00:47:39.360 | And I certainly hear a lot from people

00:47:43.520 | who played these high contact sports

00:47:46.120 | and then to their surprise later,

00:47:50.720 | they have diminished testosterone levels.

00:47:52.560 | I also work with a number of military groups

00:47:55.900 | that talk about this, that they leave

00:47:58.420 | and maybe it's from combat related stress, et cetera,

00:48:00.840 | but they wonder whether or not there's any

00:48:03.240 | traumatic head injury or maybe pituitary injury

00:48:06.180 | related impairment to the reproductive axis

00:48:10.200 | that includes brain, pituitary and the testes.

00:48:13.640 | Do you see that?

00:48:15.560 | And if somebody played a contact sport,

00:48:17.840 | in particular a contact sport where the head was hit

00:48:19.800 | or they were hitting things with their head often,

00:48:22.600 | or if they have a TBI or had a TBI,

00:48:25.120 | that their reproductive health can be impaired.

00:48:28.960 | - That's fascinating, I have not.

00:48:32.440 | I mean, I think it's interesting, I guess,

00:48:34.640 | what the pituitary does,

00:48:35.840 | you've obviously covered this before,

00:48:37.680 | but it does go to a lot of our therapies.

00:48:39.560 | I mean, so for your listeners,

00:48:42.360 | that pituitary produces two hormones,

00:48:44.440 | LH, luteinizing hormone and FSH,

00:48:46.280 | follicle stimulating hormone,

00:48:48.000 | which then stimulates the testicle.

00:48:49.340 | So the luteinizing hormone stimulates the late excels

00:48:52.440 | to make testosterone and then the follicle stimulating hormone

00:48:56.000 | or FSH stimulates sperm production.

00:48:58.320 | So both of those are very key in terms of production.

00:49:01.280 | And interestingly, when exogenous testosterone is used,

00:49:04.840 | it shuts down that axis, as you know,

00:49:06.560 | so we get less of these gonadotropins, this LH, FSH,

00:49:09.880 | to stimulate the testicle.

00:49:12.960 | And the other sort of reason that sperm production is lost

00:49:16.780 | with exogenous testosterone uses it

00:49:18.920 | is actually the intratesticular testosterone

00:49:20.960 | is much higher than serum levels.

00:49:23.420 | So, you know, our serum levels are between 300 to 900

00:49:28.420 | nanograms per deciliter on average,

00:49:30.740 | but in the testicle are probably 10 fold higher at least.

00:49:33.700 | So when men are given exogenous testosterone

00:49:36.740 | and they're not producing their own,

00:49:38.020 | the levels of testosterone in the testicle,

00:49:40.500 | which are necessary for sperm production

00:49:42.240 | are much, much lower.

00:49:43.440 | But it's interesting 'cause I think,

00:49:48.160 | I am not aware of sort of how traumatic injuries

00:49:50.780 | would do that.

00:49:51.980 | - Okay, that's good to know.

00:49:55.600 | I'm curious about the non-endocrine,

00:50:00.600 | non-chemical effects on sperm quality

00:50:06.880 | and testosterone levels.

00:50:08.560 | So here I'm thinking about a bunch of news stories

00:50:12.280 | we heard a few years ago about how bicycle seat pressure

00:50:15.880 | on the prostate, or maybe it was other portions of the,

00:50:19.920 | it was the nerves running to the penis itself

00:50:23.720 | or surrounding areas, maybe it was pelvic floor related

00:50:25.920 | and somehow you'll tell us I'm sure,

00:50:28.500 | was impairing sexual function.

00:50:30.660 | Was it impairing sexual function in any way

00:50:32.880 | by impairing testosterone levels,

00:50:34.760 | cutting off blood flow to the testes?

00:50:36.860 | And here, perhaps the most important thing to ask

00:50:40.200 | straight off is, is riding a bicycle bad

00:50:43.340 | for male reproductive health and sexual health?

00:50:46.880 | - Yeah, these are great questions.

00:50:48.000 | These are, again, living in the Bay Area,

00:50:49.960 | working in the Bay Area, cycling is very, very popular.

00:50:52.800 | So these are questions that I get a lot.

00:50:54.860 | So I think, in general, like we talked about before,

00:50:59.400 | anything that's good for your heart,

00:51:00.560 | it's gonna be good for fertility.

00:51:02.140 | So good diet and exercise, maintaining good body weight.

00:51:05.060 | And so I always try and encourage physical fitness.

00:51:07.460 | I think that's important.

00:51:09.100 | But it may be possible that some particular activities

00:51:13.840 | may put men at more risk.

00:51:15.740 | So I think cycling could be one of them

00:51:17.560 | if, but it would sort of depend on exactly

00:51:20.400 | why we think that may be a problem.

00:51:21.920 | So I guess the theory is heat.

00:51:23.720 | If you're in the saddle for a long time,

00:51:25.360 | for these prolonged rides that men take on weekends, hours,

00:51:30.360 | that may be if there's too much heat exposure,

00:51:33.540 | that may be the mechanism where sperm production

00:51:36.000 | would decline.

00:51:36.840 | So there have been some studies that say

00:51:37.880 | maybe five hours a week would be, that may be too much.

00:51:41.960 | So if you're above that level,

00:51:43.240 | the sperm counts have shown to be lower.

00:51:45.360 | If you're less than that, that may be okay.

00:51:46.800 | So when I talk to patients about it,

00:51:48.160 | I try and just encourage them to stand up in the saddle

00:51:51.440 | to try and again, sort of air things out

00:51:53.280 | to try and dissipate heat.

00:51:54.520 | If that's the mechanism we're gonna think.

00:51:56.760 | Regarding sexual dysfunction,

00:51:58.440 | that is thought to be pressure as you're alluding to.

00:52:02.200 | So the way that the saddle is configured,

00:52:05.400 | ideally all the pressure is put on our ischial tuberosity

00:52:08.720 | that are our sit bones.

00:52:09.660 | That's what I'm sitting on now.

00:52:11.380 | But on the saddle, there's obviously kind of the rigid nose.

00:52:14.320 | And if there's too much pressure on that,

00:52:15.800 | that actually squeezes between the ischial tuberosities

00:52:19.200 | where the main blood flow to the penis goes

00:52:22.720 | and the main nerve supply is too.

00:52:25.240 | And so if there's compression on this,

00:52:26.760 | you get this sort of lack of blood flow or ischemia

00:52:29.880 | and you can get a nerve practice as well

00:52:31.200 | if you crush these nerves.

00:52:32.460 | And so that over time can lead to problems.

00:52:35.320 | So some patients will say that after I cycle,

00:52:39.520 | things are numb down there for 30 minutes or a day,

00:52:43.640 | or I don't get erections for that sort of same amount

00:52:45.880 | of time, or sometimes men just sort of ride through it

00:52:50.000 | and hopefully things come back in a day or two.

00:52:53.160 | So that could be the mechanism.

00:52:55.480 | There are some saddles that hopefully

00:52:57.200 | there'll be a little safer.

00:52:58.200 | And I think that this sort of first was noted

00:53:01.840 | probably around 2000 or so.

00:53:04.720 | And there is a big redesign in terms of saddles

00:53:07.200 | to try and make them a little bit more anatomically correct

00:53:10.440 | to try and minimize some of this.

00:53:11.680 | And there's cycle fit that can be done or saddle fit

00:53:15.120 | rather that can be done at some of the cycling shops

00:53:16.960 | to try and look at your body position,

00:53:19.340 | look at your size and try and find a saddle that's safer.

00:53:22.260 | This doesn't happen to everybody.

00:53:25.000 | I would say maybe if you were to serve a cyclist,

00:53:30.000 | maybe 20 to 30% of men and women

00:53:32.920 | tend to be susceptible to this.

00:53:34.360 | So I think if you are having discomfort when you cycle,

00:53:37.720 | whether it be pain, numbness, or you notice dysfunction,

00:53:40.680 | I think certainly you should think about changing saddles

00:53:43.920 | or think about changing riding style.

00:53:46.240 | There's other strategies that are sometimes used,

00:53:48.140 | but it's absolutely something

00:53:49.920 | that everybody should be aware of.

00:53:52.440 | - I meant to ask this earlier,

00:53:53.520 | but I seem to recall a study that drew a correlation

00:53:57.440 | between amount of walking and maybe it was sperm quality,

00:54:01.780 | but I think it was testosterone levels,

00:54:03.960 | maybe some other metrics of male sexual health.

00:54:08.080 | Forgive me, I'm not recalling the details now.

00:54:10.500 | Is there any evidence that walking more, standing more,

00:54:15.640 | maybe even using a standing desk is beneficial

00:54:18.760 | for pelvic floor health, blood flow, prostate health,

00:54:23.760 | who knows, could be any and all of those things

00:54:26.800 | in some way that is beneficial for sperm quality,

00:54:29.640 | testosterone level, and/or overall male sexual health?

00:54:34.400 | - Yeah, I think one of the ways

00:54:36.540 | that we can characterize activity is step count, right?

00:54:38.960 | I think I have a watch that tells me that,

00:54:41.640 | it's something that I look at every day

00:54:42.840 | and kind of strive for it.

00:54:43.960 | And it turns out that the more active you are,

00:54:46.380 | it's been shown sort of looking at large national data pools

00:54:49.760 | across different age ranges

00:54:51.000 | that it is associated with testosterone levels.

00:54:53.340 | So being more active, I think, is very important.

00:54:55.400 | And that's another thing that everybody can do

00:54:58.040 | to try and improve sort of testicular function broadly,

00:55:01.020 | but testosterone specifically.

00:55:02.800 | - And do you know whether or not that can be separated out

00:55:05.540 | from the relationship between being more active

00:55:08.240 | and less obese?

00:55:09.480 | I mean, is this something that's independent of obesity?

00:55:12.660 | In other words, can we incentivize people to walk more

00:55:16.040 | simply on the promise of improved sexual health?

00:55:21.040 | - Well, I don't know.

00:55:22.080 | Sexual health will be a different one,

00:55:23.360 | but we can, I think there is association

00:55:25.480 | between testosterone levels and step count

00:55:27.920 | across different BMI straight up.

00:55:30.280 | So I think whether you have the ideal body weight,

00:55:33.040 | whether you have a few pounds to lose, perhaps,

00:55:35.700 | if you walk more, you will see higher levels of testosterone.

00:55:39.060 | - And another question I meant to ask earlier,

00:55:40.540 | and then we can close the hatch

00:55:43.020 | on exogenous testosterone therapy,

00:55:44.860 | at least for the time being, maybe we'll come back to it,

00:55:46.940 | is assuming that somebody

00:55:50.340 | can maintain adequate sperm production

00:55:52.860 | through the use of HCG or some other therapy,

00:55:55.700 | or perhaps they don't care if they're still making sperm

00:55:58.020 | 'cause they've already had children

00:55:59.620 | or they don't care to have children,

00:56:00.780 | maybe they bank sperm, in any event,

00:56:02.860 | assuming that somebody takes testosterone therapy

00:56:05.820 | because they were prescribed that,

00:56:07.960 | let's say in your clinic,

00:56:10.220 | let's just use you and your clinic as an example,

00:56:13.180 | and they are happy with the psychological

00:56:16.760 | and physical consequences of that,

00:56:19.280 | and they are comfortable with the trade-offs,

00:56:22.320 | is there any increased risk of, say, prostate cancer

00:56:27.320 | or other forms of cancer?

00:56:29.000 | And here, I'm going to assume that this person

00:56:30.580 | is keeping their lipid levels in check,

00:56:33.820 | right, 'cause you hear about some hyperlipidemia

00:56:36.300 | with testosterone therapies.

00:56:37.420 | Let's assume that they're either taking a statin

00:56:39.580 | or they're not taking a statin,

00:56:40.500 | and they're getting enough cardiovascular exercise,

00:56:42.220 | that things are in check in terms of LDL, HDL, APOB,

00:56:45.100 | and all of that,

00:56:46.580 | and their testosterone levels are now high normal,

00:56:49.020 | and they're feeling better,

00:56:50.380 | and they don't have to worry about sperm production

00:56:53.860 | 'cause they're either maintaining it or it's been banked

00:56:56.400 | or they don't care about that.

00:56:58.700 | Is there an increased risk of prostate cancer?

00:57:02.060 | My understanding is the answer is no,

00:57:04.580 | but what's the real deal?

00:57:06.420 | Does taking testosterone therapy,

00:57:07.940 | assuming all other things are being held in check,

00:57:10.580 | in a healthy check,

00:57:11.880 | does it increase the risk of any kind of cancer?

00:57:14.860 | - Yeah, I mean, this is another great question

00:57:16.780 | because I think there's a lot of myths around testosterone,

00:57:19.020 | and that's one of them.

00:57:20.620 | The origin is that prostate cancer is thought to be,

00:57:23.700 | or is, sort of androgen-mediated.

00:57:26.100 | One of the Nobel Prizes, again, decades ago,

00:57:29.620 | was awarded because it was found

00:57:30.900 | that when we lowered a man's testosterone,

00:57:33.100 | the prostate cancer would regress dramatically,

00:57:35.660 | so that put that association

00:57:37.220 | between testosterone and prostate cancer.

00:57:39.360 | So then the concern began if we were

00:57:41.180 | to either replace testosterone or augment testosterone

00:57:45.060 | and give a man testosterone,

00:57:46.100 | is that gonna alter his risk or increase his risk?

00:57:49.500 | So I think we have pretty convincing data

00:57:51.580 | that that's not the case.

00:57:52.980 | You know, there's lots of longitudinal data spanning decades

00:57:55.700 | where if a man is given testosterone,

00:57:58.180 | it doesn't change his risk.

00:57:59.600 | The reason for that, in a sort of seeming contradiction,

00:58:02.480 | you know, this contradiction

00:58:03.780 | between prostate cancer therapy

00:58:07.060 | where we lower testosterone,

00:58:08.980 | where if you give a man testosterone,

00:58:10.300 | it doesn't change his prostate cancer risk,

00:58:12.960 | is not certain, but there's this popular model

00:58:15.040 | called the saturation model,

00:58:16.340 | so that once there's enough testosterone in the body,

00:58:19.500 | and it tends to be a fairly low level,

00:58:22.300 | that all the sort of the prostate testosterone receptors,

00:58:25.860 | you know, you can kind of think of as have been filled.

00:58:27.980 | So if you were to give a man more testosterone,

00:58:29.700 | it doesn't change anything regarding the prostate cancer,

00:58:33.020 | prostate growth, any of that.

00:58:34.720 | So it is safe when we're looking at prostate cancer

00:58:37.740 | as an outcome.

00:58:39.220 | - I'd like to just take a brief break

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00:58:53.780 | Now, salt, magnesium, and potassium are critical

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00:58:58.460 | in particular to the function of your nerve cells,

00:59:01.100 | also called neurons.

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00:59:17.180 | especially people who are following low carbohydrate

00:59:19.340 | or even moderate carbohydrate and really clean diets,

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00:59:57.060 | Getting back to prostate health

00:59:59.860 | and neural innervation of the penis

01:00:03.940 | and blood flow to the penis,

01:00:06.420 | you mentioned the bike seat related issues.

01:00:10.180 | Are there other things that men should do

01:00:11.600 | in order to maintain prostate health,

01:00:14.140 | stave off prostate diseases,

01:00:16.280 | and to maintain healthy blood flow

01:00:18.500 | and neural innervation of the penis for obvious reasons?

01:00:21.960 | And we'll get into the specifics of those reasons

01:00:25.140 | in our later discussion.

01:00:27.200 | - Yeah, I mean, I think that,

01:00:28.800 | I always kind of think of the penis as a user

01:00:30.540 | to lose an organ.

01:00:31.380 | So that doesn't mean necessarily that you have to have sex,

01:00:33.800 | but normally we get erections every night,

01:00:35.580 | so that should be maintained.

01:00:36.900 | And if there's any reason to sort of suspect

01:00:38.680 | that that may not be going on,

01:00:40.400 | usually in my practice, that would be from

01:00:44.180 | some pelvic surgical intervention or something like that.

01:00:47.180 | Sometimes we can intervene to try and maintain that.

01:00:49.840 | - You're talking about spontaneous erections during sleep.

01:00:52.820 | So, and short of assigning one's partner

01:00:57.040 | to check frequency intumescence,

01:01:00.800 | what is the way that men would know that that's happening?

01:01:04.080 | Are you talking about waking up with an erection?

01:01:06.080 | Is that a requisite for knowing

01:01:08.880 | that nocturnal erections are occurring?

01:01:11.180 | - Well, yeah, I think you, yeah, you kind of caught me.

01:01:13.220 | I think that's a good question.

01:01:14.120 | So I think a lot of times you won't know,

01:01:16.040 | but I think if you have sort of normal response,

01:01:19.140 | when either by yourself with a partner,

01:01:22.160 | I think that generally means

01:01:23.920 | that you are gonna get normal erection.

01:01:25.420 | So I think, I guess when I say use it or lose it,

01:01:28.260 | it doesn't mean necessarily that the man

01:01:30.200 | has to stimulate himself or kind of make sure

01:01:33.960 | that he does have adequate function,

01:01:35.900 | because usually most of that normal function

01:01:38.960 | just occurs with his nocturnal penile tumescence,

01:01:41.880 | which we all get.

01:01:43.000 | I think sometimes men do notice

01:01:44.280 | when they wake up at night.

01:01:45.240 | Sometimes in the morning you wake up with an erection

01:01:47.240 | and men notice that, but the absence of that

01:01:49.120 | doesn't mean it's not happening.

01:01:50.180 | It likely is, just most people sleep through it,

01:01:52.520 | which is normal.

01:01:53.360 | Otherwise, men would never get any sleep

01:01:55.320 | because it happens many, many times a night.

01:01:58.260 | So I think, again, if you're not having normal function,

01:02:02.080 | I think that's something you should probably see

01:02:04.320 | a physician about.

01:02:05.720 | And then same for urinary function.

01:02:07.760 | I think if it bothers you, if you're waking up at night,

01:02:12.120 | you have to go to the bathroom often,

01:02:13.600 | if your stream is getting weaker,

01:02:14.680 | those are all sort of complaints that we hear about.

01:02:16.760 | - What is often, my understanding is that it's normal

01:02:20.900 | to wake up perhaps once during the night to urinate.

01:02:24.120 | And this is, of course, assuming,

01:02:26.140 | and again, forgive me for all the caveats,

01:02:27.880 | but I've done this long enough that, you know,

01:02:29.840 | if I don't get really granular about some of this,

01:02:31.760 | then she would say, well, what if I drank, you know,

01:02:34.240 | 32 ounces of fluid right before sleep

01:02:36.100 | and I'm urinating three times per night?

01:02:37.960 | Well, we're assuming that people are tapering

01:02:39.860 | their liquid intake as they approach bedtime.

01:02:42.320 | And that waking up once, maybe twice,

01:02:47.020 | but once in the middle of the night to urinate

01:02:48.880 | is normal for somebody, let's say age, I don't know,

01:02:51.940 | 18 to 40 and maybe from 40 to 100,

01:02:56.940 | that number might be in the one to two times per night.

01:03:00.880 | Is that about right?

01:03:01.840 | - Yeah, I mean, I think once a night, yeah,

01:03:03.080 | is normal for most men.

01:03:04.040 | And then I think, you know, if things start to bother you,

01:03:06.000 | I think you could certainly see somebody,

01:03:07.980 | but it's hard to get better than once or twice a night

01:03:10.480 | for most men.

01:03:11.320 | - My understanding is that there's a pretty good relationship

01:03:15.380 | between the nocturnal erection and the amount of REM sleep,

01:03:20.200 | rapid eye movement sleep that one is getting,

01:03:21.840 | that this tends to be more frequent toward morning

01:03:23.900 | as the proportion of rapid eye movement sleep increases.

01:03:27.560 | I don't know if that's true or not,

01:03:28.560 | but I found a couple of studies that at least point

01:03:31.360 | in that direction, no pun intended.

01:03:33.280 | So that raises a bigger issue

01:03:37.440 | that we haven't talked about yet,

01:03:38.600 | which is getting adequate amounts of quality sleep

01:03:40.980 | each night.

01:03:41.920 | And I think for most people that's seven to nine hours,

01:03:45.160 | ideally, which means getting sufficient slow wave,

01:03:48.440 | deep sleep, as well as rapid eye movement sleep.

01:03:50.600 | But nowadays, a lot of people, including young people

01:03:53.740 | who are not working excessive hours are getting, you know,

01:03:57.720 | four or five, six hours of sleep per night.

01:04:00.120 | Is there a direct relationship between getting less

01:04:03.660 | than sufficient amounts of sleep

01:04:05.080 | and sperm quality, testosterone levels and sexual health?

01:04:09.480 | - Yeah, I mean, I think certainly there's reasonable data

01:04:11.440 | for semen quality.

01:04:12.960 | And there tends to be, you know, we call like in science,

01:04:17.580 | sort of a U-shaped relationship

01:04:18.920 | so that it's not sort of linear.

01:04:20.340 | So as you get more sleep, things are better.

01:04:23.440 | There's sort of, there's this concept of too much sleep

01:04:25.560 | and not enough sleep.

01:04:26.720 | So the ideal, I think, as you pointed out,

01:04:28.420 | is seven to nine hours.

01:04:29.840 | And for men that are not getting that,

01:04:31.400 | semen quality tends to be lower.

01:04:32.720 | And then for men getting too much, we also see a decline.

01:04:36.760 | And you know, why that is, is again, not certain.

01:04:39.480 | Again, if you're able to get that much sleep,

01:04:41.640 | maybe there's other things as well that we should look at.

01:04:44.320 | But so I think kind of getting in that ideal sleep amount

01:04:48.680 | is best for semen quality

01:04:50.760 | and probably for broad testicular function as well.

01:04:53.360 | - You keep bringing up semen quality

01:04:56.640 | in a way that makes me wonder whether or not,

01:04:59.160 | is semen quality a proxy for overall vitality and health?

01:05:03.040 | Or is testosterone level a proxy

01:05:05.660 | for overall vitality and health?

01:05:07.760 | It sounds like semen quality is the metric

01:05:10.020 | that you keep coming back to in a way that,

01:05:13.120 | I have to assume reflects your clinical experience

01:05:16.760 | and the many papers that you've authored in this area.

01:05:20.540 | I think for people that hear semen quality

01:05:25.440 | and who are not interested in conceiving children now,

01:05:28.320 | or who are, which of course could include

01:05:31.120 | people who've already had children

01:05:32.360 | or who don't want children,

01:05:33.720 | semen quality sounds like something

01:05:36.880 | that relates to fertility.

01:05:40.200 | But is semen quality something that is a good goal

01:05:44.960 | for those who are interested

01:05:46.120 | in overall male vitality and health?

01:05:49.000 | Is it one of the better metrics

01:05:50.780 | of overall male vitality and health?

01:05:53.360 | - Well, I think, you know,

01:05:55.120 | I think it's an excellent marker for overall health.

01:05:57.400 | I think there are studies that support,

01:05:59.520 | it can be a measure of how healthy you are.

01:06:01.960 | You know, if you look at men with more health problems,

01:06:05.120 | they can have lower semen quality.

01:06:06.720 | But also if you look at semen quality just by itself,

01:06:09.640 | and then you look into the future, how these men tend to do.

01:06:12.540 | If they have higher semen quality,

01:06:15.240 | they tend to live longer, need to go to the doctor less,

01:06:18.640 | lower rates of cancer.

01:06:19.800 | So I think there's a lot of different ways

01:06:21.780 | that semen quality may be a good barometer of health.

01:06:25.800 | You know, why that link exists I think is not known,

01:06:30.400 | but there's lots of theories.

01:06:31.600 | So one is that probably about 10% of the male genome

01:06:34.720 | is devoted to reproduction.

01:06:36.460 | And so it makes sense given that we only have

01:06:38.160 | about 24,000 genes in the body,

01:06:40.600 | that there's a lot of overlap.

01:06:42.800 | So one gene that plays a role in reproduction

01:06:45.060 | may play a role in the cardiovascular system

01:06:48.000 | or the neurological system.

01:06:50.280 | And so if we get the first sort of sign

01:06:53.000 | that reproduction is not perfect,

01:06:54.720 | there may be some other health consequences down the line.

01:06:57.640 | Another sort of hypothesis is that,

01:07:01.440 | again, sort of going along this line

01:07:02.840 | that reproduction is one of the first things that we see

01:07:05.200 | is that gestation is sort of very critical

01:07:09.600 | to our existence, right?

01:07:12.200 | And perturbations to that system have prolonged effects.

01:07:16.640 | So the so-called sort of developmental origin

01:07:18.740 | of adult disease or the Barker hypothesis.

01:07:21.800 | And so we know that premature children

01:07:24.840 | have higher risk of cardiovascular disease,

01:07:26.840 | there have been studies to show that.

01:07:28.440 | But we also know that these gestational effects

01:07:31.760 | can also play out on reproductive function too.

01:07:34.980 | So that also may be kind of a link,

01:07:37.000 | sort of early seeding of reproductive function.

01:07:38.880 | And then that's maybe the first marker

01:07:40.620 | that we're gonna have for other health effects later on.

01:07:44.240 | There are also just sort of inherent sort of similarities

01:07:49.000 | between reproduction and some other sort of social effects.

01:07:53.480 | So kind of one sort of confounding factor

01:07:56.680 | when we're looking at some of these studies,

01:07:58.080 | I talked about looking at mortality, for example,

01:08:00.400 | and semen quality, is that there's sort of factors

01:08:03.520 | that necessarily involve reproduction.

01:08:05.380 | So children and having a partner.

01:08:08.280 | And having a partner prolongs life,

01:08:11.580 | having kids prolong life.

01:08:13.540 | Even though it feels like kids are killing you,

01:08:15.360 | if you look at studies, men with kids tend to live longer.

01:08:19.420 | So that's another possible explanation.

01:08:22.300 | But I think really sort of this health link

01:08:26.460 | between fertility I think is sort of a powerful one.

01:08:29.540 | So I do think it should be a barometer.

01:08:31.900 | I think that it should be a sort of,

01:08:33.660 | when I've given lectures on this,

01:08:35.020 | I call it the six vital sign.

01:08:36.260 | I think it's something that we should probably check

01:08:38.400 | because if there is sort of lower levels,

01:08:40.720 | that may tell us about something else going on.

01:08:43.120 | When men come in from fertility evaluations,

01:08:46.660 | a lot of times we do diagnose these new medical problems.

01:08:50.020 | Sometimes we diagnose cancer,

01:08:52.100 | sort of alluding to some of the questions you've asked,

01:08:54.740 | diabetes and some other

01:08:56.360 | very significant genetic conditions as well.

01:08:58.500 | And the first way that we would identify it

01:09:00.260 | is reproductive failure

01:09:01.660 | because their sperm counts are low and other things.

01:09:04.780 | So it is something I think that it's sort of,

01:09:08.260 | it's very important I think for people to realize,

01:09:11.020 | and it would be great I think.

01:09:12.820 | Another I think advantage to like the Centers for Disease

01:09:16.820 | Control, for example, to start tracking it.

01:09:19.540 | - Would it be a good idea for males in their 20s and 30s

01:09:23.100 | to get a sperm analysis just to have a baseline?

01:09:26.080 | I confess I'm 47 now.

01:09:28.580 | One thing I wish I had done in my 20s

01:09:30.280 | was to get my blood hormone profiles and lipid profiles done

01:09:34.340 | when I was in my teens and 20s

01:09:35.600 | because I'd have something to compare to.

01:09:37.580 | I started doing that in my mid 30s

01:09:39.900 | and I'm so glad I did

01:09:40.900 | because I can now compare to my mid 30s levels.

01:09:43.540 | I started including sperm analysis about eight years ago

01:09:48.540 | with the intention of freezing sperm.

01:09:50.460 | And I did that because I was also reading at that time

01:09:54.300 | about the increased risk of autism

01:09:57.840 | in offspring of males older than 40,

01:10:00.280 | something that I really would like your take on.

01:10:02.460 | But it seems like it's inexpensive enough

01:10:06.100 | to do a sperm analysis.

01:10:08.140 | I think now people can get it done at home.

01:10:10.820 | They have male kits,

01:10:12.060 | although I don't understand how the motility

01:10:14.160 | could be maintained if you're mailing your sperm back

01:10:17.260 | at room temperature or it's heading through the post office.

01:10:20.340 | Now everyone's imagining all these sperm traveling

01:10:22.240 | through the postal service.

01:10:24.020 | They're out there folks.

01:10:25.280 | Yeah, what are your thoughts?

01:10:28.460 | Should people invest the,

01:10:29.660 | I think it was a couple hundred dollars

01:10:31.140 | to get a sperm analysis more costly

01:10:35.280 | to get the DNA fragmentation

01:10:36.820 | than you get up into the low thousands.

01:10:39.900 | But if people have the disposable income,

01:10:42.020 | is it a good idea for them to do?

01:10:44.200 | - I mean, I think it's a worthwhile test.

01:10:45.640 | I think more information is always good.

01:10:47.700 | I think sort of one of the same reasons

01:10:51.260 | that you're talking about checking like lipid levels

01:10:55.140 | or we tell men and women to get blood pressure checked.

01:10:57.760 | I think getting that sort of early health indicator

01:11:00.340 | I think can be important.

01:11:01.660 | I think going back to not knowing exactly

01:11:03.980 | why semen quality is telling us about health,

01:11:07.260 | what the exact link may be,

01:11:09.180 | it means that if somebody is coming in

01:11:10.740 | with a low sperm count or completely absent sperm count,

01:11:13.940 | it's hard to know exactly how to counsel that person

01:11:16.580 | other than there may be reproductive difficulties.

01:11:19.940 | But I think just as sort of a marker

01:11:22.040 | for reproductive potential, I think it's useful.

01:11:24.340 | And like you said, I think it's become a lot easier.

01:11:26.300 | One of the sort of innovations in the space

01:11:29.300 | and somebody that is in the reproductive world,

01:11:32.680 | I think it's just really great to see

01:11:34.540 | sort of this influx in capital and new companies coming in

01:11:37.820 | that try to just decrease the barrier

01:11:39.680 | to getting a semen test.

01:11:41.300 | It used to be you have to go to a lab,

01:11:42.660 | schedule an appointment.

01:11:44.180 | Sometimes they would send you to a bathroom,

01:11:45.720 | which can be uncomfortable

01:11:47.300 | 'cause people are doing, you know,

01:11:48.620 | people doing a bathroom just next to you

01:11:49.980 | where you're trying to collect.

01:11:50.820 | - Oh, they would send them in a common space bathroom.

01:11:53.540 | They wouldn't even give them the quiet room

01:11:54.980 | with the red light, which is what I hear they do now.

01:11:59.300 | - Some of them do have video.

01:12:00.260 | So there are some higher level.

01:12:01.860 | - Oh, I didn't even mean videos.

01:12:03.100 | I just, I think that, okay, yes, I've done this.

01:12:05.840 | I'll just say, I mean, I've been trying to normalize things

01:12:08.220 | related to all aspects of mental health, physical health.

01:12:11.200 | So yeah, I decided to free sperm.

01:12:15.080 | And basically they sent me to a room.

01:12:17.980 | I went to a university-based clinic.

01:12:19.420 | It actually wasn't Stanford, but different university.

01:12:21.440 | And yeah, they put the cup through the window.

01:12:25.680 | They give you the cup.

01:12:26.520 | They close the door and they tell you

01:12:29.040 | that as long as that red light is on over the door,

01:12:31.080 | no one's going to walk in and then they leave.

01:12:34.100 | And I think the assumption now is that you figure it out

01:12:37.260 | one way or another, how to provide the sample.

01:12:40.680 | And then you put the sample back through the thing.

01:12:42.640 | And then one thing these clinics really need to work out

01:12:44.680 | is that anytime you're walking out,

01:12:46.520 | you see the people processing your sample as you walk out.

01:12:49.240 | So there's all this feigning of anonymity,

01:12:54.240 | but really it isn't there.

01:12:56.400 | 'Cause they're like, "See you later."

01:12:57.420 | And you're like, "Great."

01:12:59.380 | They rarely ask you questions on the way out,

01:13:01.060 | but it's a pretty simple process overall.

01:13:03.980 | And I must say that the data are informative.

01:13:08.040 | You get the volume, number, motile, forwardly motile.

01:13:12.100 | I did opt for the DNA fragmentation data.

01:13:16.620 | And I just love data.

01:13:18.160 | So I think it's really interesting.

01:13:19.520 | But again, maybe this is a good time to flag

01:13:22.400 | this set of findings.

01:13:24.920 | I believe that there seems to be a small,

01:13:27.320 | but statistically significant increase

01:13:28.860 | in the number of autistic births due to pregnancies

01:13:32.360 | where the male was over 40 at the time of conception.

01:13:37.360 | So I figured, why not free some sperm

01:13:41.640 | and it's relatively inexpensive?

01:13:43.520 | - Yeah, so I think paternal age is also something

01:13:47.020 | that's increasing in this country.

01:13:48.820 | So over the last 40 years or so,

01:13:50.620 | we've seen that the average paternal age has increased

01:13:53.540 | from about 27 and a half to about 31.

01:13:56.100 | And I should say that this is all fathers.

01:13:59.140 | So birth certificate data or birth data

01:14:02.440 | is collected at maternal level.

01:14:03.860 | So when a child is born,

01:14:06.440 | somebody comes in to collect data on the birth.

01:14:08.880 | So they ask all the characteristics of the mother

01:14:10.880 | and they also ask characteristics of the father.

01:14:13.360 | Age, education, obviously region of the country

01:14:16.400 | the child was born.

01:14:18.100 | So we don't know what number child that was for the father.

01:14:21.080 | We know it for the mother.

01:14:21.920 | They do ask, is this your first, second, third, et cetera,

01:14:24.440 | child?

01:14:25.420 | So the father, unfortunately we just have data

01:14:27.160 | that sort of all lumped together.

01:14:29.920 | But over the last, again, 40 years, we've seen that increase.

01:14:32.740 | Interesting over the last 40 years,

01:14:34.240 | the youngest father was 11 and the oldest was 88.

01:14:38.160 | - 11? - Quite a span, yeah.

01:14:39.700 | - 88? - Mm-hmm.

01:14:41.480 | - Goodness, unrelated.

01:14:43.000 | - I don't know, I assume, I assume.

01:14:45.360 | - Goodness. - It's anonymized data,

01:14:46.880 | but I assume. - 11.

01:14:48.440 | I have to ask this, sorry to take us on a slight tangent,

01:14:51.760 | but what is the average age of puberty in males

01:14:55.360 | in the United States now?

01:14:59.040 | - Yeah, so you're asking about, I guess, sort of spermarchy,

01:15:01.560 | when like sperm production begins.

01:15:04.280 | So- - Yeah, there are a lot

01:15:05.440 | of markers of puberty, secondary sexual characteristics

01:15:08.240 | of beard growth, deepening of voice, et cetera.

01:15:09.640 | They happen at different rates in different people,

01:15:11.120 | but yeah, thank you.

01:15:12.520 | At what point are, yeah, males undergoing puberty

01:15:17.520 | at the level of, that we're talking about here?

01:15:21.120 | - Yeah, so it's, yeah, there has been data

01:15:23.200 | that we're going through puberty a little bit earlier now

01:15:25.360 | than we used to, but it really varies.

01:15:27.720 | So I think it's not, just like testosterone ranges

01:15:32.320 | between like 300 and 900, it's a wide range for anybody.

01:15:34.920 | I think for most individuals, puberty is probably 12

01:15:39.920 | to kind of 15, 16 in general.

01:15:41.800 | So I just give sort of a very wide range

01:15:44.260 | when we're gonna say that's okay.

01:15:45.560 | And some of the data I'm basing it on

01:15:47.480 | is when sperm production begins in boys.

01:15:50.840 | And it's actually not that simple to be able

01:15:53.360 | to figure that out because we don't generally talk

01:15:56.400 | to young boys about how to masturbate,

01:15:58.440 | how to collect and then check on that.

01:16:00.240 | But there's something called first morning voided urine

01:16:03.340 | where we can actually look at that.

01:16:04.760 | And there have been some studies done

01:16:06.280 | and they see if there were sort of nocturnal emissions,

01:16:08.720 | whether there's sperm in there.

01:16:09.720 | And so generally it probably starts around,

01:16:12.320 | the earliest would be kind of 11, 12, 13,

01:16:17.340 | but usually most is probably a little later.

01:16:19.160 | So maybe I'll refine that puberty

01:16:21.560 | and move it a little bit later, probably 14 to 16

01:16:24.960 | is when probably about 70, 80% of boys

01:16:27.680 | are gonna have started producing sperm.

01:16:30.100 | - My understanding is that in females,

01:16:32.980 | puberty is also shifting earlier,

01:16:34.680 | perhaps at a more dramatic rate

01:16:36.800 | than appears to be the case for males.

01:16:38.940 | - Well, I think there is some data for males too.

01:16:40.880 | I think, but again, for your listeners,

01:16:43.480 | I don't wanna have this onslaught of pediatricians

01:16:47.320 | seeing kids that haven't, when boys haven't gone

01:16:49.400 | through puberty by a certain age.

01:16:51.200 | So I think it's still fairly wide.

01:16:53.820 | - Let's get back to age of the father

01:16:57.520 | and issues like autism.

01:16:59.800 | What are the data there?

01:17:02.600 | And this to me is a practical issue

01:17:06.880 | because I think if there's one obvious takeaway

01:17:09.800 | from our discussion today,

01:17:10.920 | it's that males should probably not wait

01:17:14.400 | until they're trying to conceive

01:17:16.260 | in order to assess their reproductive health

01:17:19.040 | at the level of sperm quality, testosterone levels, perhaps,

01:17:23.600 | but at least sperm quality.

01:17:24.900 | But perhaps men should also be freezing their sperm

01:17:29.680 | if in fact conceiving children after 40

01:17:32.760 | places their children at far greater risk for autism.

01:17:34.840 | I mean, my understanding is that the rates of autism

01:17:36.660 | are somewhere between one and 80.

01:17:38.800 | You'll hear as high as one in 50 male births,

01:17:40.940 | but I think it's probably more like one in 60 to 80.

01:17:43.320 | Is that about right?

01:17:45.640 | And that the age of the father is a risk factor.

01:17:49.640 | - Yeah, I think that this gets into sort of the larger issue

01:17:52.040 | of how men sort of perceive fertility.

01:17:54.600 | So we know that as women age fertility declines,

01:17:58.260 | but the oldest father ever is 96.

01:18:00.060 | So the biologic potential certainly persists.

01:18:03.080 | - Wait, I want to know how long he lived

01:18:05.160 | to see how long his child would grow up.

01:18:07.680 | He conceived at 96?

01:18:09.760 | - Supposedly, supposedly, yeah.

01:18:11.240 | - Well, I'm assuming he did not meet his grandchildren,

01:18:13.360 | at least not the grandchild of that child.

01:18:15.200 | So, wow, how long did he live?

01:18:16.980 | - Well, so this is a man in India.

01:18:22.380 | It's just sort of a famous story,

01:18:23.640 | but supposedly he had a child.

01:18:27.080 | He had that child with him on,

01:18:29.440 | like they're waiting at a bus stop.

01:18:30.540 | He fell asleep.

01:18:31.380 | The child was kidnapped and led to divorce.

01:18:33.280 | So yeah, sort of a horrible end,

01:18:36.700 | but the wife was also old, not that old, but in her 50s.

01:18:41.700 | So yeah.

01:18:43.640 | - Wow, tragic and incredible story for separate reasons.

01:18:47.960 | Okay, I'll get my head around this 96 year old

01:18:51.900 | conceiving a child.

01:18:53.240 | Okay, please continue, yeah.

01:18:55.720 | - So people, I think, or men think that the,

01:18:58.280 | sort of the fertile road is sort of infinite,

01:19:03.280 | but I think that's very much not the case.

01:19:06.620 | So as you're alluding to,

01:19:07.760 | people have looked into risks for older fathers.

01:19:10.560 | So about a hundred years ago,

01:19:12.220 | I was first noticed that dwarfism or chondroplasia

01:19:14.780 | was more common in last born children.

01:19:17.440 | So eventually that link was made.

01:19:19.380 | And since then, other conditions too.

01:19:22.540 | So there's like these neuropsychiatric conditions

01:19:24.540 | you're talking about, like autism is certainly one,

01:19:27.180 | bipolar schizophrenia, people have looked at

01:19:29.220 | and also linked that with older age,

01:19:31.180 | you know, less attainment in school,

01:19:34.100 | you know, failing grades,

01:19:35.420 | all that has been shown to be a little bit more common

01:19:38.060 | with older fathers.

01:19:39.420 | So, you know, why I think all of these exist,

01:19:42.700 | there can be sort of different explanations.

01:19:44.940 | You know, one explanation for the autism association,

01:19:48.500 | I'll talk about, you know, some of this more genetic

01:19:53.260 | or kind of mutational reasons,

01:19:55.440 | but one thing that some people say is that, you know,

01:19:58.240 | it could be sort of a hereditary trait.

01:20:00.020 | And so it may be that, you know,

01:20:01.660 | men that display some sort of autistic characteristics,

01:20:05.580 | you know, maybe they take a little longer to meet a partner.

01:20:09.120 | And so it sort of delayed child-bearing.

01:20:11.380 | So maybe that's one possible explanation.

01:20:14.300 | But I think, you know,

01:20:15.140 | there's been a lot of convincing evidence

01:20:16.940 | that there could be, you know,

01:20:17.800 | real epigenetic changes that occur with age

01:20:20.380 | and mutational changes that occur with age.

01:20:22.640 | I think I read a statistic and you would know more

01:20:25.500 | being a neuroscientist that 84% of the genes

01:20:28.740 | in our body are expressed somewhere

01:20:30.080 | in the central nervous system.

01:20:32.020 | Does that make you- - Sounds about right.

01:20:34.340 | Yeah. - Yeah.

01:20:35.180 | - I don't want to stamp my name to that,

01:20:38.600 | but that sounds about right.

01:20:40.020 | - So it's estimated that every year

01:20:43.420 | we generate about two mutations in our, you know, sperm DNA.

01:20:48.420 | So you can imagine that, you know,

01:20:50.220 | a 40-year-old is gonna have, you know,

01:20:52.700 | 20 or 40 more mutations than a 20-year-old.

01:20:57.700 | So that rate does go up.

01:20:58.940 | And if you're just randomly sprinkling mutations,

01:21:01.400 | you know, in, you know, a genome,

01:21:03.980 | that they're more likely to sort of manifest

01:21:05.980 | in, you know, maybe neuropsychiatric conditions.

01:21:09.300 | So there are, you know, data, convincing data

01:21:13.140 | that shows that that does occur.

01:21:14.360 | Now, again, there's billions of base pairs in the body.

01:21:16.860 | So these random mutations, likely most of them

01:21:19.160 | will not result in anything,

01:21:20.540 | but there can be some meaningful ones.

01:21:21.840 | So for example, a chondroplasia is due to a mutation

01:21:25.320 | in fibroblast growth factor receptor.

01:21:28.380 | And what's interesting is that this condition

01:21:31.120 | is not that rare, right?

01:21:32.720 | Based on sort of these rare mutations,

01:21:34.320 | you'd expect this would, you know,

01:21:36.140 | occur maybe about one in 100 million,

01:21:38.160 | but it turns out these conditions occur

01:21:40.760 | in about one in, I think, 30 to 50,000 or so.

01:21:43.920 | So there's sort of this discrepancy

01:21:45.240 | based on sort of mutational rate that we expect

01:21:47.720 | based on age and the rate that we actually see.

01:21:50.980 | So the explanation for this is something called

01:21:52.720 | selfish spermatogonial selection.

01:21:54.960 | So what this suggests is that some of these mutations

01:21:57.400 | that occur randomly occur in proliferation pathways.

01:22:00.840 | And so it gives the sperm that contain these

01:22:03.000 | sort of advantages over their, you know,

01:22:05.240 | brothers and sisters that don't have them, for example.

01:22:07.440 | And so then they out-compete the other sperm,

01:22:10.560 | and so they're more likely to lead to a child

01:22:12.340 | rather than sort of a random smattering.

01:22:14.200 | You can actually see that some of these mutations

01:22:15.800 | are more common in older men than younger men

01:22:18.240 | if you look, you screen for some of these mutations

01:22:20.280 | in some of these pathways.

01:22:22.140 | Again, the longer that we're exposed to life,

01:22:25.180 | there's just more likely to be, you know,

01:22:26.640 | different chemical exposures, other exposures.

01:22:28.600 | And so people have looked at epigenetic signatures,

01:22:31.200 | sort of these signatures that, you know,

01:22:33.760 | that dictate which genes are gonna be expressed

01:22:35.600 | and which aren't.

01:22:36.740 | And there are different patterns

01:22:37.780 | between older and younger fathers.

01:22:39.240 | And, you know, what triggering those is not known,

01:22:41.580 | but there are differences.

01:22:42.840 | So those could also potentially explain, you know,

01:22:45.040 | some of these risks that we see.

01:22:46.680 | You know, it used to be that people thought that,

01:22:49.440 | you know, if you're an older father,

01:22:50.640 | maybe there's a lot of advantages,

01:22:52.600 | you know, for the kids, right?

01:22:53.680 | 'Cause if you're more resourced, right?

01:22:55.520 | I always tell patients that, you know,

01:22:57.460 | when they come to see me for like erection problems

01:22:59.360 | or anything, I always say,

01:23:00.200 | nothing gets better with age, right?

01:23:02.280 | And that's mostly true, although they pointed out

01:23:03.920 | that salary often goes up with age

01:23:06.440 | and wisdom goes up with age.

01:23:07.680 | So you would imagine if you're more resourced,

01:23:09.600 | maybe the kids are gonna also have an advantage to that.

01:23:11.980 | But, you know, again, there's a lot of convincing data

01:23:14.320 | that that's probably not the case.

01:23:17.180 | There's even, there's one study that I saw

01:23:19.480 | that showed that if you look at MRIs of brains of children,

01:23:24.260 | just after birth, they're actually a little smaller

01:23:26.520 | for older fathers compared to younger fathers.

01:23:28.920 | So I think there are some, you know,

01:23:32.080 | sort of talking about kind of neurocognitive development,

01:23:35.400 | some of those effects.

01:23:36.400 | And there's also been studies looking at cancer risk too.

01:23:39.920 | So higher risk of breast cancer, prostate cancer

01:23:42.680 | in adult children, higher risk of, you know,

01:23:45.640 | leukemia or CNS cancers in children as well.

01:23:49.000 | So I think the more we look,

01:23:50.300 | the more we find out of these associations

01:23:52.060 | with paternal age.

01:23:53.400 | So I think it's something to certainly be aware of.

01:23:55.900 | I think you talking about mitigation strategies,

01:23:58.000 | I think sort of education would be important for,

01:24:00.360 | you know, couples to try earlier,

01:24:02.200 | you know, individuals to try earlier to conceive.

01:24:04.500 | You know, if we think it's a mutational reason,

01:24:06.240 | I think, you know, certainly freezing sperm,

01:24:08.740 | I think is a good option as well.

01:24:10.620 | - My understanding is that analysis of DNA fragmentation

01:24:15.800 | in sperm does not allow for selection of the best sperm

01:24:20.800 | on the basis of a DNA composition translated to English.

01:24:26.280 | What I mean is in order to tell whether or not

01:24:28.360 | the DNA are mutated in a sperm,

01:24:29.880 | you have to kill the sperm basically.

01:24:32.000 | So, and since in a given pool of sperm, so to speak,

01:24:37.000 | there will be forward motile, non motile, twitchers,

01:24:41.960 | twitching in place, dead sperm,

01:24:44.400 | some percentage of dead sperm or a motile sperm

01:24:46.320 | is presumably normal, some small percentage, hopefully.

01:24:50.640 | And that some might have some DNA fragmentation,

01:24:54.080 | some might not.

01:24:54.960 | So is the way to address this averages?

01:24:59.160 | What I'm hearing here is that if you haven't already

01:25:01.320 | had kids or if you want more kids,

01:25:03.020 | that you might want to know about your sperm quality,

01:25:07.880 | I would say you do.

01:25:08.860 | And that if you can afford it,

01:25:11.000 | you might want to take a look at DNA fragmentation data.

01:25:14.760 | But having done this, what one receives is a chart

01:25:18.400 | that goes from red, bad to green, good.

01:25:21.320 | And then they put the arrow, hopefully in the green zone,

01:25:24.720 | and then you say, oh, good, I'm in the green zone,

01:25:26.880 | I don't have fragmented DNA in my sperm.

01:25:29.200 | But really that's an averaging of all the sperm, right?

01:25:31.680 | It could be that as you age,

01:25:33.800 | that some percentage of those sperm have fragmented DNA.

01:25:38.240 | And if one of those is the one that successfully

01:25:41.440 | wins the eggs, so to speak, fertilizes the egg,

01:25:47.160 | then that fragmented DNA containing sperm

01:25:50.080 | is going to propagate that into your offspring.

01:25:52.400 | So are there any technologies that can allow men

01:25:55.000 | to select for or improve the DNA of their sperm,

01:26:00.000 | not just the motility?

01:26:03.520 | - I mean, yeah, I wish, right?

01:26:04.480 | That's sort of the holy grail,

01:26:05.840 | because I think you pointed out sort of a variant

01:26:07.440 | of the Heisenberg uncertainty principle is that we can't,

01:26:10.000 | if we identify which sperm is bad,

01:26:11.840 | we're necessarily going to destroy it.

01:26:13.560 | So to tell which one is harboring these mutations

01:26:16.720 | would be great, but I think we're not there yet.

01:26:18.520 | I mean, one thing that we do do is wash sperm.

01:26:20.640 | So we do sort of select the most motile sperm.

01:26:23.840 | We clear out the dead ones.

01:26:25.520 | And I think embryologists are pretty good

01:26:27.320 | at telling which sperm they think are better.

01:26:28.880 | But again, we don't have any real objective data

01:26:31.440 | to try and understand which are harboring

01:26:34.240 | something or other.

01:26:35.080 | But I think if we understood more about this link with age

01:26:37.040 | or again, other conditions,

01:26:39.200 | hopefully we would be able to stop some of this pass-through.

01:26:42.200 | - Let's get back to the prostate, this incredible gland.

01:26:47.500 | Tell us about the prostate.

01:26:48.700 | I think we hear about the prostate,

01:26:50.240 | we hear about prostate cancer.

01:26:51.720 | People might've heard that it's involved

01:26:55.280 | in the ejaculatory response.

01:26:56.880 | It's involved in erections.

01:26:58.880 | It's involved in a number of things.

01:27:00.480 | If you could give us a catalog of things

01:27:03.320 | that the prostate does.

01:27:04.880 | I mean, you spent a lot of time thinking about this gland.

01:27:07.240 | What are some of the cooler things that it does

01:27:09.920 | that we don't know about?

01:27:11.160 | How do we keep it healthy?

01:27:14.680 | And what are the consequences of not keeping it healthy?

01:27:17.600 | - Yeah, so the prostate is a gland

01:27:19.320 | about the size of a walnut.

01:27:20.560 | It sits behind the bladder

01:27:22.000 | and it's involved in reproduction.

01:27:23.280 | It produces some of the proteins, enzymes

01:27:25.760 | that are necessary for sperm to be supported

01:27:29.160 | and ejaculate to kind of keep the sperm healthy

01:27:32.320 | in the female reproductive tract.

01:27:35.400 | So it functions in reproduction

01:27:38.640 | and then basically after reproduction is done,

01:27:41.240 | it doesn't really serve any useful function.

01:27:42.920 | So then it just becomes a problem essentially.

01:27:45.280 | So the urethra, which is where we pee through,

01:27:47.440 | so it connects the bladder to exits the body,

01:27:50.880 | runs right through the prostate.

01:27:52.160 | And as we age, the prostate does get bigger.

01:27:54.040 | That's sort of a known thing.

01:27:55.160 | And as the prostate gets bigger,

01:27:57.200 | it creates sort of more resistance in this pipe.

01:27:59.560 | And so it makes the bladder have to work harder

01:28:01.320 | and that leads to a lot of the symptoms

01:28:03.560 | that we've been talking about already.

01:28:05.040 | Waking up at night, weak stream,

01:28:07.520 | this need to urinate urgently,

01:28:10.480 | sometimes feeling like you're not emptying all the way.

01:28:13.080 | So it's sort of a consequence

01:28:14.660 | of the prostate sort of being there.

01:28:17.160 | In terms of ways that you can keep the prostate healthy,

01:28:19.240 | I think that there's really nothing

01:28:20.940 | that necessarily you can do.

01:28:22.480 | I think that one thing I talk to patients about

01:28:24.680 | when these sort of symptoms start

01:28:26.240 | is to know some of the triggers.

01:28:28.020 | So like you mentioned,

01:28:29.720 | drinking a lot before you go to bed.

01:28:31.580 | So if you don't wanna wake up at night,

01:28:32.920 | that's not a good practice.

01:28:34.040 | You may even wanna go into bed sort of a little dehydrated

01:28:36.960 | just so you can try and last the night.

01:28:39.360 | There are some particular drinks or foods

01:28:42.080 | that tend to be more irritating.

01:28:43.360 | So like spicy foods, acidic foods,

01:28:45.240 | those can sometimes irritate the lining of the bladder

01:28:47.840 | and make you have to pee a little bit more.

01:28:49.840 | Caffeine is a diuretic, so it makes us urinate more,

01:28:53.840 | and it can also irritate the bladder

01:28:57.160 | and give you that sensation.

01:28:58.080 | Alcohol will do the same thing.

01:28:59.800 | So I think kind of knowing some of those triggers

01:29:02.160 | may kind of stave off some of the symptoms a little bit.

01:29:04.160 | But again, if you enjoy those vices

01:29:07.040 | and you're willing to tolerate it, that's okay too.

01:29:10.240 | - I'm hearing more and more about a practice

01:29:12.100 | of people taking low dose to dalafil, Cialis.

01:29:16.720 | Low dose, meaning in the neighborhood

01:29:18.620 | of 2.5 to five milligrams per day,

01:29:22.020 | not necessarily for erectile dysfunction,

01:29:24.580 | but for prostate health.

01:29:26.060 | And was somewhat surprised to learn

01:29:29.120 | that those drugs were actually developed first

01:29:31.180 | for treatment of prostate health,

01:29:33.640 | to increase blood flow to the prostate.

01:29:35.600 | Is that true?

01:29:38.100 | And is there a good reason to think about taking 2.5

01:29:43.100 | to five milligrams of to dalafil per day,

01:29:46.280 | simply for maintaining blood flow to the prostate

01:29:50.080 | and thereby maintaining or improving prostate health?

01:29:52.960 | - I mean, certainly it can do that.

01:29:54.240 | It can definitely help with some of these urinary symptoms

01:29:56.360 | that we've been talking about.

01:29:57.720 | You know, looking at placebo controlled trials,

01:29:59.520 | sort of our highest level of evidence does show that,

01:30:02.280 | you know, low dose of to dalafil is two and a half

01:30:04.540 | to five milligrams.

01:30:05.380 | Daily dosing can help with these urinary symptoms.

01:30:08.880 | So I think that not necessarily it's a preventative measure,

01:30:11.920 | but for men that are bothered, you know,

01:30:13.680 | otherwise I think most men probably wouldn't want

01:30:16.000 | to take a pill every day,

01:30:17.320 | but certainly if you have some of these symptoms,

01:30:18.720 | it can definitely help with urinary bother.

01:30:20.460 | And then the added benefit is you also alluded to,

01:30:22.300 | is it can help with erectile function as well.

01:30:25.100 | - Even at the 2.5 to five milligram dosage, interesting.

01:30:28.980 | Yeah, my experience is that there are a lot of people

01:30:31.500 | who would love to take pills every day.

01:30:34.520 | There seems to be a kind of binary distribution where,

01:30:37.220 | and here I'm just thinking about the males that I hear from,

01:30:41.920 | because I hear from of course, males and females,

01:30:43.960 | but I get a lot of questions about what can I take?

01:30:47.140 | What can I take?

01:30:47.980 | What can I take?

01:30:48.800 | But as you point out, there's also a category of men

01:30:52.680 | who seem to not want to take anything,

01:30:54.880 | not want to measure anything, not want to take anything,

01:30:57.400 | but especially not take anything.

01:30:58.780 | And then there's the other group.

01:31:00.500 | And the other group somewhat surprisingly

01:31:02.720 | seem to be the younger, excuse me, population

01:31:05.840 | who maybe grew up in the YouTube era

01:31:07.900 | or maybe in the era where sexual health

01:31:10.040 | was discussed more openly than it was

01:31:12.180 | certainly when I was in college.

01:31:13.280 | I mean, the extent of sexual health discussions

01:31:15.880 | at my high school, and I went to a very good high school,

01:31:18.100 | where it only takes one sperm,

01:31:20.560 | which as you pointed out is true for IVF,

01:31:22.160 | but more is better if you're trying to conceive naturally.

01:31:25.600 | And there were discussions about communication and consent,

01:31:29.120 | obviously super important.

01:31:31.760 | And then they just kind of turned us loose

01:31:34.960 | to learn from our friends and other sources.

01:31:37.640 | I mean, and family sometimes had the discussion,

01:31:40.640 | sometimes didn't.

01:31:41.540 | Different families, different discussions, obviously.

01:31:45.640 | So very little information.

01:31:48.200 | Nowadays, I think there's a lot more discussion

01:31:49.880 | about these things.

01:31:50.920 | And so the 20 to 40 year old male crowd

01:31:55.120 | seems to be the crowd that are asking,

01:31:56.920 | yeah, what can I take?

01:31:58.160 | These are also the people who are getting on

01:31:59.800 | testosterone therapy early, perhaps without the need.

01:32:04.400 | I just want to flag that because I think,

01:32:08.680 | if I understand correctly,

01:32:10.320 | you're seeing a lot of testosterone therapy

01:32:13.320 | that perhaps people don't need.

01:32:14.960 | Is that right?

01:32:15.920 | - Well, I think it's a mix.

01:32:16.840 | Some people probably do need it,

01:32:18.000 | but I think that before starting it,

01:32:20.320 | everybody should be aware of all the risks

01:32:21.800 | and you've kind of highlighted some.

01:32:23.720 | Testosterone, any medication is going to have some risks.

01:32:27.120 | And so everybody needs to be aware of what those are.

01:32:28.760 | And for testosterone, reproduction is certainly one of them.

01:32:31.480 | - And if they're not already doing all the other things,

01:32:33.400 | getting adequate sleep, limiting their alcohol intake,

01:32:36.320 | not smoking, getting exercise, et cetera,

01:32:39.040 | seems that testosterone therapy

01:32:40.700 | would not be the primary entry point.

01:32:42.880 | Like first work out all the basics.

01:32:45.700 | I think that's the big difference.

01:32:46.840 | I think nowadays the what should I take question

01:32:48.800 | comes up early when people aren't necessarily doing

01:32:51.380 | all the other things that they could do

01:32:53.640 | to promote their health.

01:32:54.680 | Anyway, this is observational on my part.

01:32:58.480 | You're the one who's clinic they're showing up to.

01:33:01.560 | I have a question about UTIs.

01:33:04.240 | We hear about UTIs, urinary tract infections

01:33:07.320 | in women pretty often.

01:33:09.640 | Do men get UTIs?

01:33:13.000 | If they're getting more than one UTI per year,

01:33:15.800 | is that abnormal?

01:33:17.780 | Should men be examined for this bladder,

01:33:22.780 | urethra, prostate, penile architecture?

01:33:26.460 | I know there are ways that people can come in.

01:33:28.080 | I was reading about this prior to this episode

01:33:30.160 | that can ingest a dye and then they can dye image

01:33:33.680 | the whole apparatus, is that right?

01:33:35.520 | - That's true. - Without having to cut

01:33:37.040 | anything, is that right?

01:33:38.600 | Is that worth people doing or is that only under conditions

01:33:41.160 | where people are experiencing some vexing issue?

01:33:45.860 | - Yeah, I think that some of those tests

01:33:47.760 | should only be done if there's a problem.

01:33:48.980 | But I think a male urinary tract infection is rare enough

01:33:52.360 | that it should be evaluated.

01:33:53.760 | So women have very short urethras,

01:33:55.920 | but men have a very long urethra, right?

01:33:57.500 | It has to go through the entire penile urethra,

01:33:59.560 | the prostatic urethra up into the bladder.

01:34:01.320 | And so the way a urinary tract infection would happen,

01:34:05.280 | one way would be that a bacteria actually gets

01:34:07.500 | all the way back and that's just a much longer trek.

01:34:11.520 | And so if something rare like that does happen,

01:34:14.360 | we look for anatomic causes for that.

01:34:16.080 | So there can be different scar tissue in the urethra,

01:34:18.560 | for example, there can be stones in the bladder,

01:34:20.800 | there can be stones in the kidney.

01:34:22.600 | Sometimes men aren't emptying their bladders all the way.

01:34:24.680 | So those men should be evaluated

01:34:26.400 | because there can be some pathology

01:34:27.860 | that we could hopefully identify and correct.

01:34:30.600 | - Let's talk about erectile dysfunction.

01:34:33.300 | I put out the call for questions

01:34:35.360 | in anticipation of this episode.

01:34:37.260 | And no surprise, at least 30% of the questions

01:34:42.260 | from males were about erectile dysfunction.

01:34:45.940 | Or questions about what's normal in terms of libido level.

01:34:52.020 | Kind of interesting, right?

01:34:54.920 | And we'll deal with the first question first,

01:34:57.140 | but what are the most common causes of erectile dysfunction?

01:35:01.840 | Are they hormonal in nature?

01:35:03.560 | I think that's a common belief

01:35:05.500 | that if people are experiencing erectile dysfunction,

01:35:07.560 | that it's because their testosterone levels are too low.

01:35:09.920 | Hence all the interest in testosterone therapy.

01:35:14.280 | Or are there other, say blood flow related,

01:35:16.640 | pelvic flow related, neural brain to body neural connections

01:35:21.800 | that are responsible, I'm guessing it's all of these things.

01:35:24.180 | How do we parse this and tell us about erectile dysfunction,

01:35:29.180 | what you most commonly see,

01:35:31.660 | what you most commonly do in order to treat it.

01:35:34.320 | - Yeah, so erectile dysfunction, as you know,

01:35:37.040 | is sort of the inability to consistently achieve

01:35:39.960 | and maintain an erection.

01:35:41.280 | And it's fairly common, of all the conditions I see,

01:35:44.880 | that's definitely the number one.

01:35:46.640 | So if you look at men who are experiencing erectile dysfunction

01:35:49.840 | so, you know, if you look at men over the age of 40,

01:35:52.520 | over half will have some trouble with erections.

01:35:55.160 | Under age of 40, it's probably about 15 to 20%.

01:35:57.800 | So this is a very common condition that we see.

01:36:00.540 | In terms of the etiology, it can vary a little bit.

01:36:02.800 | You know, we used to think

01:36:03.640 | that they were primarily psychogenic,

01:36:06.280 | but that was, you know, years, that was decades ago.

01:36:09.200 | Now we know that most of them are organic,

01:36:10.920 | so it's actually a blood flow issue.

01:36:12.760 | So the most common conditions, just sort of nationally,

01:36:15.680 | would be the same things that cause blood flow problems

01:36:18.160 | anywhere in the body.

01:36:18.980 | Like blood pressure, diabetes, you know, atherosclerosis,

01:36:21.120 | anything that sort of can impair blood getting,

01:36:24.280 | you know, to the end organ.

01:36:25.760 | And sometimes, you know, there has been data that,

01:36:28.100 | you know, trouble with erections can actually predate

01:36:30.980 | other more, you know, serious, you know, vascular conditions.

01:36:34.120 | So the blood vessels in the penis,

01:36:35.540 | the penile arteries are about one millimeter, you know,

01:36:38.160 | and the heart and the brain, they're much larger.

01:36:41.480 | So, you know, it's much easier to occlude a small vessel

01:36:44.400 | than a large vessel.

01:36:45.240 | So that's why there have been some studies to support

01:36:47.700 | that it's sort of an early marker for vascular disease.

01:36:51.240 | So I think looking at those risk factors, you know,

01:36:54.280 | sort of lifestyle, obesity, again, is another,

01:36:56.640 | is a common one.

01:36:58.420 | Endocrine disorder is actually fairly small.

01:37:00.440 | It's probably less than 10%, probably around 5% or so.

01:37:03.500 | Pelvic cancer treatment is another very common one

01:37:07.240 | after, you know, treatment for prostate cancer,

01:37:09.440 | whether it be radiotherapy or surgical therapy,

01:37:11.560 | bladder cancer, sometimes rectal, colorectal cancer,

01:37:15.580 | that treatment also.

01:37:16.420 | Anytime we're, you know, involving some of the nerves

01:37:19.720 | and the vasculature and the pelvis,

01:37:22.520 | that can also impact erectile function as well.

01:37:25.880 | - What about hernia?

01:37:27.680 | - Hernia, that should be separate.

01:37:29.420 | So sometimes if they're, you know,

01:37:31.020 | I always say that in medicine, you can never say never.

01:37:34.260 | But, you know, generally if that was gonna manifest

01:37:36.560 | as erectile function, it would probably be due to

01:37:38.760 | maybe some pain syndromes can rarely happen

01:37:40.680 | during just the early post-operative period.

01:37:42.360 | But the blood supply, the nervous supply is separate.

01:37:46.120 | - So you said something very important for people to hear,

01:37:50.740 | so I'm gonna highlight it.

01:37:52.080 | You said that less than 10% of erectile dysfunction

01:37:55.780 | is due to a hormonal issue.

01:37:57.780 | I don't know how much time you're spending

01:38:00.720 | on YouTube and the internet,

01:38:02.160 | but that is going to be a shocker for a lot of males

01:38:06.900 | out there because so much of the discussion

01:38:09.140 | around testosterone is around libido and sexual function.

01:38:12.880 | So it's key for people to hear that.

01:38:15.840 | It's also key for them to know about this other 90%.

01:38:20.440 | When you say blood flow issue,

01:38:22.120 | then what is the common first pass for treatment?

01:38:27.000 | And again, and forgive me for listing this off

01:38:29.960 | over and over, but we are assuming here

01:38:31.860 | that people have gotten their body weight down,

01:38:33.240 | they're sleeping enough,

01:38:34.140 | they're not ingesting excessive alcohol,

01:38:36.040 | they're not smoking or vaping,

01:38:37.760 | they're not smoking cannabis or doing the edibles,

01:38:41.440 | although maybe we should talk about edibles

01:38:42.740 | and cannabis and endocrine effects, we'll do that later.

01:38:45.160 | - Doing all the things right,

01:38:46.720 | avoiding doing the wrong things too often

01:38:51.040 | or at least completely.

01:38:52.380 | So we're assuming they're doing all that correctly.

01:38:54.820 | Their testosterone levels are somewhere in that 300

01:38:57.360 | to 900 nanogram per deciliter range.

01:39:00.400 | That's typical for the so-called reference range

01:39:03.840 | in at least in the US, I think it goes up to 1200

01:39:06.220 | or maybe 1400 in other countries,

01:39:07.840 | but as other countries like to point out,

01:39:10.860 | but it starts at two, no, I'm just kidding.

01:39:15.120 | But assuming they're doing everything correctly

01:39:17.420 | and it's not a testosterone issue,

01:39:20.200 | then if it's a blood flow issue,

01:39:23.320 | meaning they haven't had treatment for some pelvic cancer,

01:39:27.080 | what is the first line of treatment?

01:39:30.800 | - Yeah, so assuming that lifestyle

01:39:32.760 | and all that has been optimized,

01:39:33.880 | medical treatment has been optimized,

01:39:35.740 | there's a lot that we can do.

01:39:36.780 | I always tell men, as long as you have a penis,

01:39:38.260 | we can always make it hard.

01:39:39.680 | So there's a tremendous amount.

01:39:41.080 | - I'm sure that you're the most popular doctor

01:39:43.240 | in your field as a consequence.

01:39:44.080 | - Yeah, that usually does kind of ease everybody.

01:39:46.620 | So usually we start with oral therapy.

01:39:49.160 | So phosphodiesterase inhibitor therapy.

01:39:51.660 | So that would be like sildenafil or Viagra,

01:39:53.600 | Tidalafil, Cialis, Avanafil, Stendra or Vardenafil, Levitra.

01:39:58.600 | - Would you be willing to talk

01:39:59.580 | about some of the specifics there?

01:40:00.680 | Are you, is the typical thing to put people

01:40:03.200 | on this 2.5 to five milligrams per day low dose

01:40:05.760 | or to give the higher doses that are more commonly used

01:40:10.460 | for erectile dysfunction per se?

01:40:13.220 | - I think it depends, you know,

01:40:14.500 | why we're putting them on it

01:40:15.600 | and how much sex they have too.

01:40:17.480 | You know, on average, people probably have sex,

01:40:20.180 | you know, partnered sex maybe once a week on average.

01:40:22.740 | You know, when we're looking at men

01:40:24.380 | in their kind of thirties and beyond, you know,

01:40:26.680 | sometimes it can be a few more times a week than that.

01:40:28.660 | But you know, if they're having sex every day

01:40:31.760 | or very often, then sometimes a daily dose can be useful.

01:40:34.160 | But generally, most men are on just on demand

01:40:37.040 | 'cause they're gonna fall into that, you know,

01:40:38.140 | maybe about, you know, a few times a month category.

01:40:41.040 | So that's usually where we start.

01:40:42.720 | And you know, there are sort of a titration

01:40:44.840 | that can be done.

01:40:45.680 | You can go slightly, you know, higher doses or lower doses.

01:40:47.820 | So usually we start in the middle to the higher doses.

01:40:50.460 | And you know, we talk about some of the side effects

01:40:53.820 | they may have, but those probably help 60 to 70% of men

01:40:57.040 | and they work well.

01:40:58.120 | You know, in terms of another common question

01:40:59.640 | is how do we decide which one we're gonna start?

01:41:01.880 | Sometimes insurance will tell us which one we're gonna do.

01:41:04.800 | That's a common one.

01:41:06.040 | You know, all these medications tend to be somewhat similar.

01:41:08.960 | One difference tends to be the time of onset.

01:41:12.480 | You know, how quickly they reach peak levels in the body

01:41:14.760 | and then also how quickly they're cleared from the body.

01:41:17.560 | So Tidalafil is somewhat different and then it lasts longer.

01:41:20.520 | The half-life is about 20 hours or so.

01:41:23.420 | So it's sort of marketed as a weekend pill.

01:41:25.340 | So some people like the idea of that, you know,

01:41:27.020 | taking a pill on Friday,

01:41:28.480 | still having some left on Saturday.

01:41:30.240 | But for others, you know, we start with one of the other ones.

01:41:34.680 | - The fact that these drugs like Tidalafil,

01:41:38.440 | also called Cialis, right?

01:41:39.620 | - Cialis, yeah.

01:41:40.460 | - Is Cialis the brand name?

01:41:41.280 | - Right.

01:41:42.120 | - And Viagra, is that a brand name?

01:41:44.400 | - Right.

01:41:45.240 | - Stands for, what is the generic name?

01:41:48.060 | - Sildenafil.

01:41:48.900 | - Sildenafil, okay.

01:41:49.740 | So because they are effective

01:41:52.260 | in such a large percentage of cases,

01:41:54.240 | what does that say about the vascular system

01:41:56.520 | of all these males that are having erectile dysfunction,

01:42:00.980 | but then it's getting resolved by these drug treatments?

01:42:03.080 | Is that, in other words, somebody comes into your clinic,

01:42:06.120 | they're having this issue, you prescribe one of these drugs,

01:42:10.060 | they come back and say, "Everything's working great,"

01:42:13.680 | or maybe they don't come back, they just, you know,

01:42:15.400 | send an email and say, "Everything's great."

01:42:18.280 | But do you need to have a discussion with that person

01:42:20.660 | about their overall vascular health?

01:42:22.760 | Because a few minutes ago, you told us that

01:42:24.900 | the fact that they weren't getting erections

01:42:26.480 | due to what now appears to be a vascular issue

01:42:29.720 | can be resolved for the penile tissue,

01:42:32.360 | but is it going to solve their other vascular issues

01:42:35.200 | or should those people be on the lookout

01:42:36.920 | for cerebrovascular, cardiovascular disease

01:42:39.620 | that can potentially cause things at least as bad

01:42:42.380 | as erectile dysfunction or maybe worse?

01:42:44.360 | - Yeah, no, absolutely.

01:42:45.200 | Well, I think they should be screened.

01:42:46.260 | So, you know, sometimes I'm diagnosing in the first doctor

01:42:50.360 | that they're seeing in a long, long time,

01:42:52.480 | but otherwise I do encourage them

01:42:53.860 | to see a primary care doctor to be screened

01:42:55.600 | for blood pressure, lipid levels, fasting, blood glucose,

01:43:00.000 | all those things, again, sort of for early markers

01:43:02.000 | or some of these.

01:43:02.820 | Sometimes they're identified, sometimes not,

01:43:04.480 | but I think it's, you know, I think we kind of talked about

01:43:07.080 | sort of the ideal patient that's perfect body weight,

01:43:09.040 | nothing else is going on,

01:43:09.960 | but that's, as you know, a very rare entity.

01:43:12.400 | So usually there's something that can be done

01:43:13.980 | to be optimized.

01:43:14.880 | And I don't, I try not to be alarmist about this,

01:43:17.240 | but I do want to, you know,

01:43:18.480 | encourage men to sort of take ownership of the health

01:43:20.540 | 'cause that sometimes can improve, you know,

01:43:23.360 | some of these conditions.

01:43:24.300 | But again, we have terrific medications

01:43:25.940 | for men in whom we cannot.

01:43:28.160 | - What are the common side effects of these drugs?

01:43:31.080 | - So they're vasodilators, they open up blood vessels,

01:43:33.440 | so we get some off-target effects.

01:43:35.020 | So headache, facial flushing, backaches,

01:43:37.880 | leg cramps, indigestion, nasal congestion,

01:43:40.520 | those would be the most common.

01:43:42.520 | - Before the last Super Bowl,

01:43:43.760 | there was some press about the fact

01:43:45.200 | that a lot of the players were taking these drugs

01:43:47.400 | at low dosages before the game,

01:43:49.320 | presumably to increase blood flow to their muscles

01:43:51.400 | and brain, is that what the rationale was?

01:43:53.680 | - I think so, yeah.

01:43:54.520 | You know, another is we talked about sort of how

01:43:56.960 | cycling may lead to erectile problems or sexual problems.

01:43:59.960 | There has been some data looking at taking like Viagra

01:44:03.640 | or one of these medications, Cialis, Todalafil,

01:44:05.720 | before a ride, again, to try and increase circulation

01:44:08.360 | to decrease the chance of any of the negative effects

01:44:10.840 | of prolonged saddle pressure.

01:44:13.080 | - So it sounds like just increasing blood flow

01:44:15.160 | and lowering blood pressure slightly

01:44:16.680 | is just a good thing all around.

01:44:18.640 | - Yeah, I think there's certainly a benefit.

01:44:19.840 | Yeah, 'cause these medications were originally,

01:44:21.620 | I think, as you're alluding to,

01:44:22.640 | were developed as a blood pressure treatment.

01:44:24.840 | And this was sort of an amazing off-target effect

01:44:27.560 | that has turned into a billion dollar industry.

01:44:29.840 | - So you mentioned about 10% or less

01:44:33.440 | of erectile dysfunction is due to endocrine issues.

01:44:36.080 | Was it 60 to 70% can be resolved

01:44:39.480 | with these blood flow enhancers?

01:44:43.760 | I know that's a terribly nonclinical,

01:44:46.640 | non-scientific way to describe it,

01:44:48.160 | Viagra, Cialis, Todalafil, et cetera.

01:44:52.260 | What about the remaining percentage

01:44:55.440 | and are there other treatments that you prescribed

01:44:59.600 | or given, in which cases do you need to resort to,

01:45:04.600 | I guess, more invasive approaches?

01:45:06.800 | - Yeah, so another therapy we have

01:45:08.980 | is urethral suppository.

01:45:10.180 | So you can actually put a medication

01:45:11.600 | in the tip of the penis

01:45:12.440 | and send absorbed by the rest of the penis.

01:45:14.560 | - Also inject, it's suppository.

01:45:16.340 | - It's suppository or a gel, or a jelly, yeah.

01:45:19.480 | So it's also a vasodilator.

01:45:20.900 | Sort of the concept is very similar.

01:45:22.840 | Sometimes that is okay for men and they tolerate it.

01:45:27.560 | It's safe for partners as well.

01:45:30.400 | It can tingle a little bit.

01:45:31.600 | So we definitely let men know

01:45:33.040 | 'cause one of the main medications

01:45:35.240 | does cause like a little bit of a burn as well.

01:45:37.840 | - Why would somebody do this

01:45:38.800 | as opposed to taking the pill form

01:45:40.680 | of the drugs we were just talking about?

01:45:43.080 | - Mostly efficacy would be a big one.

01:45:45.200 | And so this can sometimes help where others cannot.

01:45:48.980 | So that's one.

01:45:50.600 | Penile injections are another common therapy.

01:45:53.400 | So the efficacy of penile injections

01:45:55.200 | are probably 80 to 90%.

01:45:57.260 | Again, we're injecting vasodilators into the penis.

01:45:59.980 | So the idea is just opens up blood vessels,

01:46:02.320 | easier to get and to keep erections.

01:46:04.240 | You can imagine there's a huge psychological barrier

01:46:06.100 | to putting a needle in your penis.

01:46:08.500 | - Is this something that the patients

01:46:09.640 | are doing for themselves at home

01:46:10.880 | or that you're doing, is it long lasting?

01:46:12.940 | Is that something you do at the clinic

01:46:14.620 | and then they come back every few weeks or so?

01:46:16.960 | - No, yeah, this is an on-demand treatment.

01:46:18.720 | So we teach them how to do it

01:46:20.960 | the first time they do it with us in clinic.

01:46:22.880 | Ideally, we try and get an erection

01:46:24.680 | that lasts probably 20 or 30 minutes.

01:46:26.000 | So we usually start at a low dose

01:46:27.840 | and then they just increase at home

01:46:29.140 | until they get an erection that lasts

01:46:31.240 | for that amount of time.

01:46:32.240 | - Is it injected subcutaneous

01:46:33.960 | or actually into the, goodness,

01:46:37.520 | the meteor tissue of the penis?

01:46:39.520 | - That's right, yeah, into the erectile bodies directly.

01:46:41.620 | Yeah, and you only have to inject one side.

01:46:43.840 | They do communicate with each other.

01:46:45.640 | Most men say it's fine.

01:46:47.460 | It's a small, it's a very small gauge needle,

01:46:49.040 | about as big as a few strands of hair.

01:46:51.040 | - I'm an appointment over in ophthalmology

01:46:52.640 | and I've seen injections into the human eyeball

01:46:54.940 | and it is incredible how fast

01:46:58.380 | and how painless that procedure is

01:47:00.080 | when it's done by the right person.

01:47:01.440 | Nobody should try that at home on their own,

01:47:03.300 | but when it's done by a skilled ophthalmologist,

01:47:05.700 | it's just striking.

01:47:06.540 | You hear, you think about needle in the eye,

01:47:08.600 | what's worse?

01:47:09.520 | It's like the childhood rhyme, right?

01:47:10.760 | Stick a needle in my eye.

01:47:11.600 | So you can't think of anything worse,

01:47:12.840 | but maybe an injection in the penis sounds almost as bad,

01:47:17.420 | but you're telling me that if patients are prescribed this,

01:47:19.980 | that they can do this with limited, if any, discomfort.

01:47:22.880 | - Well, it does have a high dropout rate.

01:47:25.680 | - Surprise, surprise.

01:47:27.400 | - Yeah, I think no one's excited about it.

01:47:28.920 | It's, I guess the mood can sometimes be affected,

01:47:31.960 | but a lot of couples are very comfortable with it.

01:47:33.580 | Again, it's very efficacious.

01:47:34.660 | The man can do it, his partner can do it.

01:47:37.080 | So it does work well.

01:47:39.020 | - And I guess here we're sort of ascending

01:47:43.500 | the list of invasiveness.

01:47:45.920 | What is at the sort of top tier of invasiveness

01:47:50.760 | for erectile dysfunction?

01:47:52.540 | - So then we go into penile implants.

01:47:54.780 | So there's actually a surgical procedure we can do

01:47:56.700 | to put a device inside the penis

01:47:58.080 | that can help men be hard when they want to.

01:47:59.700 | And that comes in sort of two main forms.

01:48:02.520 | There's either non-inflatable or inflatable.

01:48:05.780 | So the non-inflatable is sort of a bendable.

01:48:08.240 | It has sort of a metal core.

01:48:10.460 | And so when men don't wanna have sex, they bend it down.

01:48:13.220 | When they're ready for sex, they can kind of bend it up.

01:48:15.620 | - It's really just they're on demand.

01:48:17.280 | - Yes, yeah.

01:48:18.980 | - Interesting. - Yeah.

01:48:19.960 | So it's very simple to use.

01:48:21.720 | Sort of the more, I guess,

01:48:23.260 | kind of sort of natural form would be the inflatable.

01:48:26.620 | So when you're not using it, it's deflated.

01:48:28.520 | And then when you're ready to use it, it's inflated.

01:48:30.120 | And you inflate it with basically a pump

01:48:32.700 | that's in the scrotum.

01:48:33.640 | So all this is sort of surgically implanted inside a man

01:48:36.500 | all under the skin.

01:48:38.100 | Unless you know what you're looking for,

01:48:39.500 | it'd be very difficult to tell

01:48:40.680 | if a man has it or doesn't have it.

01:48:42.360 | But when he's ready, he pumps it up

01:48:43.980 | and it moves fluid from a reservoir,

01:48:46.980 | which usually is also surgically implanted

01:48:49.860 | into the penis to get a rigid erection.

01:48:51.800 | - What is the relationship

01:48:53.900 | between psychological arousal and erection

01:48:57.180 | as it relates to these technologies?

01:48:58.820 | I mean, the way you're describing it

01:48:59.860 | sounds purely mechanical, right?

01:49:02.780 | We're talking about nocturnal erections,

01:49:04.380 | which I suppose people could be having erotic dreams,

01:49:06.980 | but I don't think that's a prerequisite

01:49:09.540 | for nocturnal erections at all, right?

01:49:11.820 | So is the idea that if adequate blood flow is achieved,

01:49:17.180 | then any signal from the brain can initiate a cascade

01:49:21.160 | of blood flow that creates the erection?

01:49:23.860 | Or is it the case with some of these treatments

01:49:26.220 | that it sounds like blood flow is almost autonomous?

01:49:31.220 | - Right, well, I think a lot of these,

01:49:33.340 | yeah, the blood flow is not adequate

01:49:34.700 | and that's why we're having to sort of go beyond.

01:49:37.040 | But generally, as you point out,

01:49:38.220 | there's different stimulation,

01:49:39.340 | whether it be visual, tactile, or factory,

01:49:43.100 | that sort of starts that cascade

01:49:46.060 | that releases neurotransmitters in the penis

01:49:47.920 | that leads to this vasodilation naturally,

01:49:50.700 | and men get erections.

01:49:52.220 | - Few years ago, I was reading about vasopressin inhalants.

01:49:57.220 | There was a bunch of stuff hitting the market.

01:49:59.660 | By the way, I don't suggest that people

01:50:01.880 | get experimental with this stuff.

01:50:04.020 | As a neuroscientist who also knows the thing

01:50:06.500 | about neuropeptides and neurohormones

01:50:08.560 | that can impact the hypothalamus,

01:50:10.740 | I just cover my eyes and kind of cringe

01:50:13.900 | when I think about people inhaling vasopressin thinking,

01:50:16.380 | oh yeah, there's a study that vasopressin

01:50:18.860 | increases sexual desire or something like that.

01:50:21.260 | But nowadays, I'm reading a lot more

01:50:24.500 | about a really interesting peptide treatment,

01:50:27.700 | which I think is a FDA-approved prescription drug,

01:50:30.180 | which relates to a melanocyte-stimulating hormone

01:50:35.180 | that comes out of the medial pituitary

01:50:37.500 | that is used to increase sexual desire.

01:50:40.980 | It's prescribed for women.

01:50:43.620 | But men are starting to take it.

01:50:45.480 | And it seems to have,

01:50:46.980 | at least from what you read on the internet,

01:50:50.140 | a pretty profound impact on libido

01:50:53.060 | and on erectile frequency and persistence.

01:50:56.860 | Is this something that you're using in your clinic?

01:51:00.260 | Yeah, what about these peptides

01:51:03.620 | that people are inhaling and injecting?

01:51:05.340 | And some of them are taken in oral form,

01:51:07.220 | but most often I think it's nasal inhalant

01:51:12.380 | or it's a subcutaneous injection.

01:51:16.260 | Yeah, so those are not ones that we use in clinic.

01:51:19.220 | But I think looking at sort of

01:51:21.260 | just sexual dysfunction broadly,

01:51:23.020 | there are a lot of things that we do try and help.

01:51:26.540 | And one of the things that kind of relates to that,

01:51:29.740 | that it's been a proposed treatment for it,

01:51:31.900 | is this concept of delayed orgasm or delayed ejaculation.

01:51:35.720 | So I think everybody's familiar

01:51:36.980 | with premature ejaculation, right,

01:51:38.400 | where men ejaculate too quickly.

01:51:40.460 | But on the other end of the spectrum,

01:51:41.660 | there's men that takes a long time to ejaculate.

01:51:45.700 | And what that is is sort of defined differently,

01:51:48.980 | but generally most people would say

01:51:50.240 | like sort of two standard deviations above average.

01:51:52.500 | So on average, probably around five minutes or so,

01:51:55.060 | two standard deviations would be kind of 20 to 25 minutes.

01:51:57.660 | So for men that take that long to ejaculate,

01:52:00.060 | that would be considered delayed.

01:52:01.260 | Or sometimes they don't ejaculate

01:52:02.700 | every time that they have relations.

01:52:05.300 | So for those, I think there is a need for treatment

01:52:07.740 | because there's no FDA approved therapy for that.

01:52:10.100 | And so that's why I think providers are trying

01:52:12.940 | some of these other more experimental things.

01:52:15.380 | There's some that we use, just not that one in particular.

01:52:19.020 | There's also some devices that have been trialed as well,

01:52:21.260 | but it's a challenge because I certainly

01:52:23.980 | really feel for these men.

01:52:25.820 | It's one of the pleasures in life.

01:52:27.580 | And some of them are never able to have sex

01:52:29.380 | or only, or sorry, never able to orgasm,

01:52:31.580 | and some are only able to do it very rarely.

01:52:34.060 | So we do want to offer them benefit.

01:52:36.660 | What about pelvic floor health more generally?

01:52:40.100 | The topic of pelvic floor health is something

01:52:42.420 | that comes up more often around female reproductive health

01:52:46.420 | and urology.

01:52:47.300 | You hear about Kegels, Kegels, Kegels, I don't know.

01:52:52.860 | I guess we'll have to ask him because it turns out Kegel,

01:52:55.540 | Kegel was a person who named the exercise after himself.

01:52:59.820 | Whether or not he did them or not, I do not know.

01:53:03.000 | But my understanding is that Kegels

01:53:05.260 | are a pelvic floor strengthening exercise.

01:53:07.900 | And my understanding is that some people

01:53:13.060 | experience urinary or sexual dysfunction

01:53:16.760 | because of a overly relaxed, aka weak pelvic floor,

01:53:21.760 | but that some people have the exact same problems

01:53:24.980 | because of a hyper contracted, aka overly tense,

01:53:28.860 | tight, strong pelvic floor.

01:53:31.380 | Meaning don't run out and start doing Kegels

01:53:33.560 | just 'cause you heard about them.

01:53:34.700 | They're not good for everybody.

01:53:35.700 | They might be bad for certain people.

01:53:37.940 | But what about pelvic floor health?

01:53:39.620 | I mean, should men be paying attention

01:53:40.900 | to pelvic floor health?

01:53:41.740 | Should men be doing pelvic floor exercises?

01:53:44.260 | - I mean, I think it's really key that you say that

01:53:45.900 | 'cause not everything you hear about is good.

01:53:47.900 | And I think it's not good for the right person.

01:53:49.740 | So there are certainly men that I see that have very,

01:53:52.660 | just a lot of tension, a lot of anxiety.

01:53:54.640 | Sometimes these men urinate every hour.

01:53:57.020 | I mean, there's other things that you could just tell.

01:53:58.640 | They're just sort of very wound up.

01:54:00.620 | And I think for that man, one of the issues

01:54:03.620 | you kind of allude to is he probably needs to relax more.

01:54:05.660 | So pelvic floor physical therapy can still benefit you

01:54:08.860 | 'cause there are some just different feedback exercises

01:54:10.900 | that could be done to help with relaxation.

01:54:12.440 | So in the urologist office,

01:54:14.900 | there's usually a list of a lot of different providers

01:54:16.740 | around the region that can help with some of these.

01:54:19.300 | Kegel exercises though can be useful, for example,

01:54:21.980 | for prostate cancer rehabilitation.

01:54:24.860 | Some of these men where we're trying to kind of rebuild

01:54:27.500 | some of the strength or maintain or improve continents

01:54:30.280 | in these men.

01:54:31.120 | We do wanna strengthen some of these muscles

01:54:33.020 | just so that they can sort of recreate or replace

01:54:35.700 | what was lost when the prostate was removed.

01:54:37.540 | So I think for the right man, they can be useful,

01:54:39.900 | but yeah, it could be a dangerous tool in the wrong hands.

01:54:43.460 | - And you mentioned that if people want to learn more

01:54:45.260 | about pelvic floor therapy,

01:54:47.460 | they can contact their local urologist

01:54:51.100 | and find a good pelvic floor,

01:54:53.380 | good male pelvic floor specialist.

01:54:55.220 | Do they tend to specialize male, female?

01:54:57.500 | - They're usually pretty much gender or sex agnostic.

01:55:00.780 | So they usually are able to help all.

01:55:03.720 | - And forgive me for asking

01:55:06.420 | for an abridged anatomy lesson here,

01:55:08.520 | but could you describe the pelvic floor muscles

01:55:12.080 | and how they relate to the bladder prostate,

01:55:15.020 | urethra penis anatomy that you talked about before?

01:55:18.300 | 'Cause I have the picture

01:55:19.820 | of the bladder urethra prostate penis in my brain.

01:55:23.640 | I know my life experience where the testes in scrotum

01:55:29.540 | are relative to all of that,

01:55:30.500 | but now I'm trying to figure out how like,

01:55:33.040 | so the pelvic floor,

01:55:33.880 | a bunch of muscles that are attached to the pelvis,

01:55:36.500 | but how do they interact with those organs?

01:55:40.460 | - Yeah, it's a good question.

01:55:41.420 | So they sit beneath the sort of in the perineum.

01:55:44.460 | So the area between the scrotum and the anus

01:55:46.880 | and back beyond too.

01:55:47.980 | So they basically support all the structures there.

01:55:50.260 | They support the base of the penis, the prostates,

01:55:53.820 | the bladder, the rectum,

01:55:55.980 | and they kind of keep main adequate tension

01:55:59.640 | to keep all those structures up.

01:56:00.960 | They relax when different functions are necessary.

01:56:04.060 | They're very important for ejaculation.

01:56:06.820 | Some people think that they kind of trigger

01:56:08.280 | some of the orgasmic response as well.

01:56:10.380 | Sometimes men will have pain in that area,

01:56:14.520 | in the perineal area can transmit to other parts of the body

01:56:17.500 | like the scrotum.

01:56:18.860 | One cause of scrotal pain and there can be many

01:56:21.960 | can sometimes be pelvic floor dysfunction.

01:56:23.700 | So I think, again, pelvic floor therapy can be useful

01:56:27.780 | for sort of a constellation of symptoms

01:56:30.000 | against some urinary symptoms as well.

01:56:32.080 | So I think for some patients it can be helpful,

01:56:34.540 | but again, if you get things too tense,

01:56:39.020 | that can sometimes be harmful.

01:56:40.440 | - So presumably these pelvic floor therapists

01:56:42.580 | also help people achieve a more relaxed pelvic floor

01:56:45.260 | if that's what they need.

01:56:46.200 | - Exactly.

01:56:47.040 | - Got it.

01:56:47.880 | Going to some of the questions that came back to me

01:56:52.040 | when I solicited for questions

01:56:53.340 | in anticipation of this episode.

01:56:56.380 | Several, not a few.

01:56:57.880 | Let's say a couple of dozen people asked

01:57:00.260 | about split urine stream.

01:57:03.140 | Is that a signature of prostate overgrowth?

01:57:06.900 | Is that a urethral issue?

01:57:09.100 | Is it perfectly normal?

01:57:10.420 | I'm assuming here they mean a split stream of urine

01:57:15.300 | that doesn't unify at any point.

01:57:17.660 | They're talking about a consistently split urine stream.

01:57:20.940 | And for those of you that don't know what I'm talking about,

01:57:22.300 | we're talking about a urine stream

01:57:23.740 | that's actually two urine streams.

01:57:25.060 | And we're assuming one urethral opening

01:57:27.740 | 'cause I hit the literature on this.

01:57:29.300 | And there is a case of a failure

01:57:31.460 | to fully fuse the urethral duct during development

01:57:34.220 | where some, I'm assuming small fraction of males

01:57:38.720 | have a urethral opening on the base of the penis

01:57:40.720 | and at the tip of the penis.

01:57:42.380 | Let's rule that out as a possibility for now.

01:57:45.120 | But now that it's on the table,

01:57:47.820 | what percentage of males have that two urethral openings?

01:57:51.780 | - So well, hypospatias, which you're describing

01:57:54.060 | where the actual meatus is not at the tip,

01:57:57.260 | but it's kind of along the proximal urethra

01:58:00.500 | or even further down sometimes in the scrotum,

01:58:02.500 | probably about 1% of births.

01:58:04.000 | And usually it's recognized at birth

01:58:06.560 | and oftentimes it's surgically corrected

01:58:08.300 | 'cause it's better to prepare it early rather than later.

01:58:11.740 | - Okay, so ruling that out,

01:58:13.720 | what is the cause of split urine stream

01:58:16.900 | and is it a signature of a larger issue?

01:58:20.460 | - One of the reasons that we urinate

01:58:22.220 | sort of from an evolutionary standpoint, right,

01:58:25.180 | is to basically deposit in sort of a convenient time

01:58:30.180 | our waste and we don't want to get it everywhere

01:58:32.420 | 'cause we don't want to sort of label ourselves

01:58:35.960 | with the smell of urine 'cause that'll be easier

01:58:37.620 | for predators to be able to identify.

01:58:39.400 | So just similar to today,

01:58:40.620 | we'd like everything to get in the toilet

01:58:42.140 | without creating a mess.

01:58:43.060 | So anytime there's turbulent flow,

01:58:45.980 | it certainly could signal an issue.

01:58:48.140 | So it could be like urethral issues

01:58:49.700 | or pointing out a prostatic issue, inadequate speed

01:58:53.580 | of getting the urine out of the anus.

01:58:56.220 | So you definitely should see a physician to get evaluated

01:58:59.500 | because there's likely some issue that can be improved.

01:59:02.340 | - The most popular question I received from males, however,

01:59:08.420 | was about, perhaps no surprise, penis length.

01:59:12.780 | You're an expert in this, actually.

01:59:16.560 | Not just because you're a urologist,

01:59:18.640 | male reproductive health expert,

01:59:21.280 | but you published a study recently

01:59:24.620 | on the changing trends in penile length.

01:59:29.140 | Tell us about that study.

01:59:31.980 | I have so many questions about the methodology

01:59:35.380 | because I have to assume

01:59:36.940 | this didn't involve self-report, right?

01:59:39.040 | - Those were excluded, yeah.

01:59:40.140 | - Yeah, so lying was excluded.

01:59:43.160 | Being facetious here, but yeah, how was this study done?

01:59:48.240 | I mean, pretty incredible study and the results are,

01:59:53.240 | I don't know if they're surprising or not.

01:59:54.860 | At first I thought, oh, this is surprising,

01:59:57.300 | but the results were only surprising

01:59:59.040 | in light of what you were talking about earlier

02:00:00.500 | about sperm and testosterone levels.

02:00:02.300 | I think I'll let you describe the study now

02:00:05.660 | rather than giving people the punchline here.

02:00:07.800 | - Yeah, so I mean, the origin was that we were looking at,

02:00:10.780 | we wanted to know average lengths

02:00:12.100 | for another project that we were doing.

02:00:13.720 | And going down the rabbit hole,

02:00:15.940 | this has been reported for decades.

02:00:18.180 | There's different reasons

02:00:19.100 | that people have reported penile length.

02:00:21.420 | Sometimes they do it just on volunteers,

02:00:23.860 | again, to sort of get the average lengths

02:00:25.620 | of different populations.

02:00:27.100 | Sometimes it's done pre and pro-surgically

02:00:29.120 | to try and understand what changes would occur.

02:00:31.480 | So we just sort of culled the literature,

02:00:34.160 | found data on 55,000 men all over the world

02:00:38.320 | and wanted to see if there was

02:00:39.700 | sort of a time pattern with that.

02:00:41.520 | And similar to your hypothesis,

02:00:42.920 | we assumed based on all the other data

02:00:44.660 | that we would likely see a decline,

02:00:46.760 | whether it be chemical environmental exposure.

02:00:49.200 | But if nothing else, if we're getting bigger,

02:00:51.880 | the functional penile length should decline

02:00:53.920 | because the suprapubic fat pad will get a little bit bigger.

02:00:57.680 | And so we'll kind of lose penile length with that.

02:00:59.800 | And so much to our surprise-

02:01:01.180 | - The suprapubic fat, excuse me,

02:01:03.320 | being the pad of fat directly over the penis.

02:01:05.600 | - Right, right.

02:01:06.760 | And so if that gets bigger,

02:01:08.680 | that'll necessarily compromise penile length.

02:01:10.960 | But as you alluded to,

02:01:12.560 | what we found is actually the opposite,

02:01:13.780 | that the penises were getting longer with time.

02:01:17.360 | So how it's measured, it measured differently.

02:01:19.000 | So one of our inclusion criteria

02:01:21.180 | was that all the studies have measured

02:01:23.540 | sort of in an office, sort of in a clinical setting.

02:01:26.220 | So whether it be a clinician

02:01:28.420 | or whether it be a researcher that actually did it.

02:01:30.440 | So there's different ways you can measure a penis.

02:01:32.160 | You could just do a stretch length.

02:01:33.900 | So you kind of stretch it up as much as you can

02:01:35.780 | and then use sort of a ruler to measure how long it is.

02:01:38.380 | Again, from as deep as you can get,

02:01:40.780 | the pubic bone ideally up to the tip of the glands.

02:01:44.640 | - Okay, guys, so here's what he's describing.

02:01:46.160 | He's talking about measuring from the top,

02:01:48.080 | not from the bottom.

02:01:49.700 | Believe it or not, people ask questions about this.

02:01:52.640 | - My daughter made that joke, actually.

02:01:54.140 | - Oh, yeah?

02:01:54.980 | - Yeah. - Yeah.

02:01:56.000 | Measuring from the top, not from the bottom, no cheating.

02:01:58.900 | You're talking about stretching the penis

02:02:00.140 | while it's flaccid, presumably,

02:02:01.980 | and then measuring from essentially contact

02:02:05.000 | with a location that's contact with the pubic bone

02:02:07.860 | to the tip.

02:02:09.360 | - Right. - Okay.

02:02:10.660 | So that length was recorded in 50,000 men?

02:02:15.640 | Wow.

02:02:16.480 | - Yeah, so that was one.

02:02:17.720 | And then we also looked at erect length.

02:02:19.120 | And so there's different ways that an erection

02:02:20.840 | can be achieved sort of in a clinical setting.

02:02:22.860 | So one is you could ask a man to stimulate himself

02:02:25.500 | and then measure.

02:02:26.340 | So that was some of the studies.

02:02:27.340 | And then the other method, as we alluded to earlier,

02:02:29.580 | is you could inject the man with the medicine

02:02:31.060 | to give him an erection and then measure it.

02:02:33.600 | - And did 50,000 men participate in that aspect of the study?

02:02:37.620 | - It was less.

02:02:38.460 | Yeah, I think that was about probably 10 to 15,000 men.

02:02:42.700 | - I have to wonder whether or not it's easy or difficult

02:02:44.980 | for people to recruit subjects for these studies.

02:02:47.940 | I don't know.

02:02:48.780 | I could see it going both ways.

02:02:50.020 | - Yeah, some of the studies actually had a tremendous number,

02:02:52.400 | had about like 15,000 men.

02:02:55.340 | Some individual studies contributed to that.

02:02:57.020 | And actually, interesting, after we published it,

02:02:58.680 | there were some men that volunteered

02:03:00.700 | for the next study to be measured.

02:03:02.700 | - I'm sure you'll hear from some of them

02:03:04.100 | after this episode.

02:03:06.520 | What was the major finding?

02:03:08.560 | - So the major finding we wanted to do

02:03:09.800 | is just give normative data.

02:03:11.040 | We found that it varied around the world,

02:03:12.560 | so based on different regions,

02:03:14.840 | the average lengths varied a little bit.

02:03:17.840 | But generally, on average, a wrecked penis

02:03:20.800 | is probably between about five to six inches

02:03:22.920 | somewhere in that neighborhood.

02:03:24.000 | So that was kind of the take-home we wanted.

02:03:24.840 | - That was the average.

02:03:26.000 | - The average for a wrecked length.

02:03:28.160 | - Did you publish the full distributions?

02:03:30.940 | - We didn't.

02:03:31.780 | Our plan was actually to make a follow-on study

02:03:34.880 | so we could show everybody I guess probably

02:03:37.760 | they were interested where they kind of fell on the graph.

02:03:40.280 | But it was fairly, it was normally distributed.

02:03:43.000 | - Yeah, we think that despite the wide availability

02:03:47.360 | of pornography that the distributions,

02:03:51.400 | like the scatter plots of all the data,

02:03:54.240 | would be interesting to men.

02:03:56.640 | For the same reason that the testosterone

02:04:00.280 | by function of age data published as a scatter plot

02:04:04.680 | in that textbook I referred to earlier.

02:04:06.640 | Very interesting because the scatter plot distributions,

02:04:11.160 | I feel like point to other takeaways

02:04:15.080 | that one can be in their 70s and have testosterone levels

02:04:18.900 | equivalent to a healthy male in his 30s.

02:04:21.280 | That one can be in their 30s and have testosterone levels

02:04:24.000 | that are twice as much or half as much as age match cohort,

02:04:27.940 | this kind of thing.

02:04:28.840 | I think there's value in that.

02:04:31.180 | So what other takeaways arrived with the data

02:04:36.180 | from the penis length study

02:04:38.220 | that perhaps we didn't hear about?

02:04:39.860 | Like what did you find most interesting about the data?

02:04:42.980 | - Well, that there was any change over time.

02:04:44.740 | This was a fairly short study.

02:04:46.780 | It was probably about 30 years or so.

02:04:49.340 | But we did find that penile length

02:04:50.740 | has been increasing over time.

02:04:52.220 | So that was just sort of fascinating

02:04:55.500 | that we would see sort of in such a short interval of time

02:04:57.620 | that there would be a change, number one,

02:04:58.900 | but that we'd see a lengthening, number two.

02:05:02.020 | So, again, similar to the concerns that arose

02:05:04.620 | for these relatively short period of time

02:05:07.140 | where you would see changes in semen quality,

02:05:09.940 | it suggests something sinister, right?

02:05:11.820 | It's unlikely to be a genetic change

02:05:13.820 | because that would take centuries probably,

02:05:17.500 | certainly several generations.

02:05:18.620 | So the fact that this happened so quickly

02:05:21.080 | was just surprising.

02:05:22.080 | - This brings to mind some of work

02:05:25.260 | that I was involved in years ago

02:05:28.220 | when I was a master's student.

02:05:29.220 | I studied early organizing effects of hormones

02:05:31.980 | on the brain and body.

02:05:34.460 | And I'm sure this has been updated since then,

02:05:38.360 | but my recollection is that during embryonic development,

02:05:43.360 | males are exposed to a certain amount

02:05:47.540 | of dihydrotestosterone, not testosterone,

02:05:50.580 | but dihydrotestosterone, which organizes the brain male,

02:05:54.840 | as they used to say.

02:05:56.220 | Now, the verbiage around that

02:05:58.700 | would probably be a little bit different,

02:05:59.980 | but the idea is that males are born with penile tissue,

02:06:04.980 | of course, but then it's during puberty

02:06:08.580 | that the same hormone, dihydrotestosterone,

02:06:10.940 | then exerts an activating effects on the genitals

02:06:14.540 | and the genitals grow during puberty,

02:06:16.500 | penis length increases.

02:06:18.300 | So assuming that the study that you did

02:06:20.300 | was on males post-puberty, I'm assuming it was,

02:06:25.940 | then it would imply that something's changing

02:06:28.600 | about the levels or the signaling

02:06:31.500 | related to dihydrotestosterone.

02:06:33.340 | How could that happen?

02:06:36.140 | Do we have any ideas about what might be happening?

02:06:37.980 | I mean, this is the opposite

02:06:39.060 | of environmental endocrine disruptors preventing sperm

02:06:43.100 | from being as high quality and numerous as they could be

02:06:46.300 | or environmental factors, either in utero or post-utero,

02:06:51.300 | suppressing testosterone levels.

02:06:54.000 | Here, we're talking about the opposite effect.

02:06:55.140 | We're talking about dihydrotestosterone levels,

02:06:56.780 | presumably being higher in males over the last 30 years

02:07:01.140 | and thereby longer penises.

02:07:04.000 | - Right, so I mean, I think there's different conjectures

02:07:06.080 | that you could make about why this could happen.

02:07:07.740 | I mean, it could be, you know,

02:07:08.820 | maybe endocrine disrupting chemicals, you know, in utero,

02:07:11.900 | some early exposure, you know,

02:07:13.620 | that some of the mothers had to kind of androgenic effects

02:07:16.740 | during the male programming window

02:07:18.100 | that may have led to some longer lengths.

02:07:20.960 | Another hypothesis we had is that

02:07:23.180 | if males are going through puberty earlier,

02:07:25.620 | the earlier one goes through puberty,

02:07:27.080 | the longer length tends to be.

02:07:28.820 | So maybe that provides sort of this link.

02:07:31.620 | - So earlier puberty tends to be longer,

02:07:34.580 | potentially means longer duration exposure

02:07:37.260 | to dihydrotestosterone, longer penises.

02:07:40.740 | Yeah, you may be surprised to know,

02:07:42.920 | you might not be surprised to know

02:07:45.560 | that there is a subculture online.

02:07:48.000 | I know because they contacted me

02:07:49.680 | in anticipation of this episode.

02:07:51.820 | Of post-pubertal males

02:07:55.940 | who take a combination of dihydrotestosterone

02:08:00.020 | and low levels of growth hormone

02:08:03.480 | in efforts to try and increase their penile length.

02:08:06.600 | And the ones taking dihydrotestosterone,

02:08:09.900 | they're not taking pure DHT,

02:08:11.140 | they're taking things like oxandrolone,

02:08:13.700 | which very closely mimics the structure of DHT.

02:08:16.240 | They report some success.

02:08:21.100 | Fortunately, they did not send me pictures.

02:08:23.980 | Otherwise, I would have just forwarded them to you

02:08:25.580 | for your next study.

02:08:27.220 | But this stuff is happening in post-pubertal males.

02:08:31.540 | So it all rests on this dihydrotestosterone hypothesis.

02:08:36.480 | Just a point of interest.

02:08:38.500 | - Yeah, I don't know.

02:08:39.420 | Just physiologically, it doesn't make sense

02:08:40.960 | why that would work as you're pointing out post-pubertally.

02:08:43.920 | Unless they're doing other things,

02:08:45.320 | some sort of stretching exercises or I think called julking.

02:08:48.460 | But yeah, I would not recommend that.

02:08:52.560 | - Thank you.

02:08:53.400 | That was the response I was looking for.

02:08:54.540 | So that community will be listening with open ears.

02:08:59.540 | Don't do it.

02:09:00.860 | As long as we're talking about DHT, dihydrotestosterone,

02:09:05.400 | it's only fair to discuss the drugs

02:09:09.780 | that many people take to suppress dihydrotestosterone

02:09:12.840 | in hopes to keep or grow their hair.

02:09:16.320 | Things like finasteride, dutasteride.

02:09:18.500 | Some, maybe many, not all people who take these drugs,

02:09:24.420 | particularly in oral form,

02:09:26.640 | experience sexual dysfunction issues

02:09:29.320 | and other issues related to suppressing DHT.

02:09:34.000 | That said, my understanding is that these drugs

02:09:36.120 | are also quite useful, maybe even life-saving in some cases

02:09:39.840 | for staving off certain forms of prostate cancer.

02:09:44.420 | What are your thoughts about finasteride, dutasteride?

02:09:46.660 | Do you see people coming into your clinic

02:09:48.940 | who are having sexual dysfunction or other types of issues

02:09:52.140 | because of their hair or attempt to maintain

02:09:55.540 | or grow their hair issues?

02:09:57.460 | And equally important is that we talk about

02:10:00.960 | so-called post-finasteride syndrome.

02:10:03.180 | I got a lot of questions about post-finasteride syndrome

02:10:06.320 | because I'll describe it in a couple of minutes.

02:10:09.400 | It sounds pretty devastating for these people's lives.

02:10:13.800 | And I'll explain why it's so devastating for them

02:10:16.760 | in a moment.

02:10:17.600 | But what about finasteride, dutasteride

02:10:19.360 | and these drugs that are effectively DHT blockers?

02:10:21.920 | DHT levels, if they get too high,

02:10:26.320 | indeed can miniaturize the hair follicle,

02:10:28.680 | cause people to lose their hair typically upfront

02:10:31.400 | or in the back, so-called crown or whatever,

02:10:33.920 | widow's peak or everywhere in some cases.

02:10:38.920 | It also induces hair growth on the back,

02:10:40.840 | beard growth as we understand.

02:10:42.480 | But then people go and take these drugs

02:10:44.040 | to try and maintain or grow their hair.

02:10:45.940 | And oftentimes they have erectile dysfunction

02:10:47.880 | or other issues.

02:10:48.720 | Is that surprising to you?

02:10:50.600 | - I think the men that we see these side effects are,

02:10:54.280 | tend to be younger men in their 20s, 30s and 40s.

02:10:57.560 | And they take it as you're pointing out for hair loss.

02:11:00.040 | So before it was FDA approved for that indication,

02:11:02.200 | at least finasteride was,

02:11:03.780 | they did randomized controlled trials to look.

02:11:06.160 | And one of the other things that we'll talk about too

02:11:09.200 | is just reproductive effects.

02:11:10.440 | So they did lots of studies to see if there were changes

02:11:13.160 | in semen quality for men on finasteride versus the placebo.

02:11:17.480 | And there were some very subtle changes,

02:11:19.380 | but sort of in post-marketing now,

02:11:21.120 | we see these patients in clinic.

02:11:22.720 | Everybody to enroll in these studies had normal function.

02:11:26.740 | So I think that's sort of important to understand.

02:11:28.680 | And obviously that's not life, right?

02:11:30.240 | That people come in with sort of different baselines

02:11:32.800 | and different amounts of reserve.

02:11:34.200 | And so we now know that there's probably people

02:11:36.120 | that are a lot more sensitive

02:11:37.080 | to these medications than others.

02:11:38.720 | And so there are some men that drop

02:11:40.800 | their sperm counts dramatically.

02:11:42.320 | And usually if we stop these medications,

02:11:45.600 | their sperm counts can recover.

02:11:47.100 | And usually the spermatogenic cycle

02:11:48.560 | is probably about two to three months.

02:11:49.800 | So usually in maybe three to six months,

02:11:51.880 | we usually see recovery for most men.

02:11:54.520 | But similarly for sexual function,

02:11:57.000 | I certainly have a number of patients

02:11:59.620 | that do complain of low libido erectile function,

02:12:02.000 | this post finasteride syndrome.

02:12:03.680 | And the mechanisms I think are less certain

02:12:06.400 | because measuring testosterone levels,

02:12:08.300 | which we do, sometimes if androgens are low,

02:12:10.960 | or even if androgens seem to be in the maybe normal range

02:12:13.380 | or low normal range,

02:12:14.220 | we'll try and increase testosterone

02:12:16.560 | through a variety of means.

02:12:17.560 | Testosterone, clomiphene sometimes will give.

02:12:20.520 | It helps some men, but not all.

02:12:21.940 | So I think the exact mechanism of what is going on here,

02:12:25.640 | what is changing, I think we need more understanding

02:12:30.640 | about the exact sort of pathophysiology or neurochemically.

02:12:37.000 | - It seems like a pretty serious trade off

02:12:38.720 | to either maintain or grow hair or lose sexual function.

02:12:42.280 | I mean, I've talked about DHT

02:12:44.020 | and some of these side effects of finasteride,

02:12:48.180 | dutasteride on previous episodes.

02:12:50.880 | And, you know, I'm not a clinician,

02:12:52.660 | but my encouragement is always for people

02:12:54.360 | to approach these drugs with a real level of seriousness,

02:12:58.420 | if not caution.

02:13:00.040 | The post finasteride syndrome was described

02:13:02.620 | in these online questions as seemingly permanent,

02:13:06.080 | even though people had ceased to take finasteride

02:13:11.080 | or dutasteride.

02:13:11.940 | So in other words, they were taking this stuff.

02:13:14.680 | I don't know how they felt while they were on it,

02:13:16.000 | but they stopped taking it.

02:13:17.380 | And the sexual dysfunction issues

02:13:20.240 | don't seem to be resolving.

02:13:22.160 | Does that mean they should go see you

02:13:24.640 | or another male urologist reproductive health specialist?

02:13:28.880 | - Yeah, I mean, oftentimes they do for these complaints.

02:13:31.740 | They start to notice that when they're on the medication,

02:13:35.000 | then when they usually through online research

02:13:37.340 | kind of learn about this potential entity,

02:13:39.360 | sometimes they discontinue.

02:13:40.760 | Now, some men do have resolution when they stop,

02:13:42.840 | but there is this permanence in some handful of men.

02:13:45.800 | You know, they've done MRI imaging

02:13:48.200 | to try and understand sort of more anatomically

02:13:50.840 | or functionally what exactly is going on.

02:13:52.440 | I think there's still a lot of unknowns about it,

02:13:54.880 | but it can be permanent for some.

02:13:57.000 | So they come in and they see me in clinic,

02:13:59.480 | erectile dysfunction, low libido,

02:14:00.880 | and then we go down to all the host of treatments

02:14:02.960 | that we talked about and evaluations that we talked about.

02:14:05.440 | Again, we have resolution in some,

02:14:06.800 | but there are some that seem treatment refractory.

02:14:09.360 | - Yikes, that's my only response.

02:14:11.460 | I mean, permanent effects on sexual health

02:14:16.460 | as a consequence of an attempt to maintain one's hair.

02:14:20.640 | I mean, this is where, you know, in all seriousness,

02:14:23.920 | it just sounds like something

02:14:25.440 | that people need to think very seriously about.

02:14:28.400 | Because as I understand, there's nothing that can predict

02:14:31.040 | whether or not someone will have post-phenasteride syndrome.

02:14:36.040 | Right? - Right.

02:14:37.140 | - And I did a bit of reading on this

02:14:41.000 | within the scientific journals as well.

02:14:42.600 | There isn't a lot of information, as you point out,

02:14:44.680 | 'cause it's a fairly recent phenomenon

02:14:46.120 | that highlights a different issue.

02:14:48.560 | This may be the first time in history

02:14:50.860 | where young males are taking phenasteride and dutasteride,

02:14:54.120 | and that might be the cause

02:14:56.400 | of the post-phenasteride syndrome, right?

02:14:58.640 | I think you alluded to this earlier.

02:15:00.580 | But these drugs have proven to be very beneficial

02:15:03.440 | for older men treating prostate issues.

02:15:06.020 | - Exactly, yeah. - Right?

02:15:07.160 | So this is a post-phenasteride syndrome,

02:15:09.920 | I think falls under the category of medical conditions

02:15:12.720 | that, you know, a few years ago,

02:15:14.680 | we would hear the same about chronic fatigue syndrome.

02:15:18.600 | Even fibromyalgia, not long ago,

02:15:21.240 | was considered one of these,

02:15:22.280 | oh, is it all a psychosomatic issue?

02:15:24.720 | Now, we now clearly know that's not the case

02:15:27.200 | for fibromyalgia, by the way.

02:15:29.400 | But I can recall a time not that long ago

02:15:31.260 | when people in the medical profession kind of like,

02:15:34.420 | oh, yeah, I don't know if this is a real thing,

02:15:36.680 | but post-phenasteride syndrome sounds certainly real

02:15:39.200 | for the people that are suffering from it.

02:15:40.560 | - Exactly, yeah.

02:15:41.580 | - Okay, well, the reason I'm spending so much time on this

02:15:43.320 | is that I get a lot of questions about it,

02:15:45.960 | and there are clearly a lot of young males

02:15:47.360 | who take phenasteride or dutasteride

02:15:49.220 | or are thinking of doing that for cosmetic reasons.

02:15:53.140 | And I think they should be aware

02:15:54.320 | of the potentially serious consequences.

02:15:56.420 | - Yeah, agree. - Yeah.

02:15:57.960 | - But you did say earlier that if someone has a penis,

02:16:02.040 | you can get it hard.

02:16:03.720 | So all is not lost even for these

02:16:06.760 | post-phenasteride syndromes and-

02:16:07.600 | - That's true. - Good, okay.

02:16:09.240 | We'll hold you to that. [laughs]

02:16:11.780 | You mentioned clomiphene.

02:16:13.040 | Could you explain what clomiphene is and what it's used for?

02:16:18.240 | Because, again, we want this discussion to be centered

02:16:23.240 | around the real science, the real medicine,

02:16:26.800 | but there is a growing sub-community of people out there

02:16:29.660 | who are saying, "Okay, testosterone therapy

02:16:31.800 | can cause these sperm suppressive issues

02:16:34.760 | and perhaps some other issues."

02:16:36.320 | But doing nothing might not be an option

02:16:40.160 | for somebody who wants to increase their whatever libido,

02:16:43.120 | other aspects of androgen function.

02:16:46.420 | And so there are a growing number of people out there

02:16:50.280 | who are taking clomiphene only

02:16:52.760 | in order to presumably increase testosterone.

02:16:55.520 | But my understanding is that it would impact

02:16:57.940 | the estrogen pathway as well.

02:17:00.500 | Yeah, what's clomiphene?

02:17:01.780 | What are your thoughts about people using clomiphene,

02:17:04.740 | sort of off-label, simply to increase androgens?

02:17:08.560 | Seems sketchy to me for reasons related

02:17:11.000 | to changes in neural circuits.

02:17:13.140 | But you'll tell us how it works.

02:17:16.180 | - Well, thank you for including the off-label disclosure.

02:17:18.040 | Anytime I talk about this, I always have to say that.

02:17:21.500 | So clomiphene is a selective estrogen receptor modulator.

02:17:24.240 | So basically it blocks estrogen.

02:17:26.040 | And so from our earlier discussions

02:17:27.760 | of how the pituitary works,

02:17:29.680 | there's sort of an elaborate feedback loop

02:17:31.260 | between the pituitary and the gonads

02:17:33.760 | and the man, the testes.

02:17:35.000 | And so what happens is FSHLHC's gonadotropin

02:17:38.760 | stimulate the testicle to make sperm and testosterone.

02:17:41.380 | Testosterone is peripherally converted to estrogen

02:17:43.640 | and that feeds back on the hypothalamus to stop that.

02:17:46.760 | So again, you don't get an overproduction.

02:17:48.940 | So by blocking the estrogen receptor

02:17:50.960 | at the level of pituitary or the hypothalamus,

02:17:53.760 | you'll stop that.

02:17:55.440 | And so the idea behind blocking that

02:17:57.200 | is that you'll get more production of FSHLHC's,

02:17:59.800 | more of these drivers.

02:18:01.200 | So you get more testosterone,

02:18:02.800 | you get a higher stimulation of the testicle.

02:18:05.040 | You know, the hope is that for fertility

02:18:06.880 | that sometimes it can improve sperm production too.

02:18:09.040 | And there's some limited data that can help.

02:18:11.200 | But I think as you're alluding to,

02:18:12.920 | it's sort of a way to just augment

02:18:14.660 | your body's own production of testosterone.

02:18:16.920 | So it certainly does that.

02:18:17.960 | I think there's no question that testosterone levels do rise.

02:18:20.960 | I think that the reason that doesn't always help

02:18:23.200 | is because not every problem is solved by testosterone.

02:18:25.880 | We kind of talked about somewhat in this discussion,

02:18:29.240 | but also that, you know,

02:18:30.240 | you do need some estrogenic signaling as well.

02:18:32.600 | And so by blocking that, you know, even partially,

02:18:35.400 | 'cause there's also some partial agonist effects

02:18:37.120 | of clomiphene as well, it may limit it.

02:18:40.620 | And, you know, it turns out that estrogen signaling

02:18:42.720 | is important for a lot of things.

02:18:44.260 | It's important for, you know, bone health,

02:18:46.340 | but sexual health too, it's important for libido.

02:18:48.400 | So that may be partially blunting

02:18:50.520 | some of the hope for benefits of testosterone.

02:18:52.780 | I found that men tend to be happier

02:18:54.460 | on testosterone than some of these other forms,

02:18:56.420 | and that could be a possible explanation.

02:18:59.140 | But one of the advantage of clomiphene,

02:19:00.800 | if we are thinking about this as a treatment

02:19:02.620 | for low testosterone hypergunadism,

02:19:04.860 | is that it doesn't have the same toxic effects

02:19:07.000 | on sperm production.

02:19:08.300 | So by maintaining the body's own production of testosterone,

02:19:11.420 | by maintaining production of FSHLH,

02:19:14.140 | we'll continue to get sperm production.

02:19:16.220 | So for this reproductive age man that has low testosterone

02:19:19.160 | and symptomatic low testosterone, you know,

02:19:21.420 | low energy levels, sex drive, mood, sleep problems,

02:19:25.180 | it can be a worthwhile treatment.

02:19:27.120 | And it does help a lot of men, but not everybody.

02:19:30.580 | - I've always been curious why,

02:19:34.380 | if the goal is to increase sperm production,

02:19:36.580 | that the most common treatment is HCG,

02:19:40.780 | human chorionic gonadotropin.

02:19:42.500 | Because as you mentioned earlier,

02:19:44.820 | luteinizing hormone and FSH, follicle stimulating hormone,

02:19:48.560 | are deployed from the pituitary,

02:19:51.100 | and travel to the testes where they stimulate

02:19:53.620 | testosterone production and sperm production,

02:19:57.020 | but it's the FSH specifically

02:19:59.000 | that encourages sperm production.

02:20:01.480 | So why wouldn't a man who's taking,

02:20:06.480 | maybe testosterone therapy,

02:20:08.260 | or who perhaps just wants increased sperm count and quality,

02:20:11.560 | take FSH instead of human chorionic gonadotropin,

02:20:14.980 | which is more or less a proxy for luteinizing hormone?

02:20:18.160 | - That's a really good question.

02:20:19.180 | And so what FSH does, like you said,

02:20:20.940 | is it stimulates sperm production.

02:20:22.420 | So it seems like it'd be a much more logical treatment.

02:20:24.380 | And actually, in randomized placebo-controlled trials,

02:20:27.280 | it does do that.

02:20:28.320 | So one of the reasons-- - It does not.

02:20:29.340 | - It does do that, it does help.

02:20:31.120 | So it's beneficial, and we should give it more.

02:20:33.640 | But one of the reasons that we don't is cost.

02:20:35.880 | So it's rarely covered by insurance.

02:20:38.020 | And HCG, a month of that is in the hundreds of dollars.

02:20:40.940 | So let's say like three to $500.

02:20:42.940 | But a month of sort of therapeutic FSH

02:20:46.000 | is probably two to $3,000.

02:20:47.940 | So that cost is really limiting.

02:20:49.320 | It takes two to three months to make a sperm.

02:20:51.420 | So men often would have to be on it for several months.

02:20:55.280 | But there is reasonable data that would help.

02:20:56.900 | And it does make a lot more sense that that should be given

02:21:00.220 | as adjuvant therapy with testosterone rather than HCG.

02:21:03.820 | But HCG does work.

02:21:05.460 | Everyone's surprised it does actually help.

02:21:07.820 | But yeah, I agree, there is sort of a contradiction there.

02:21:10.220 | So if the price came down, it doesn't,

02:21:12.220 | this is another off-label medication for that indication.

02:21:15.640 | It would be, it could be worthwhile.

02:21:18.440 | - One hormone that we haven't discussed is prolactin.

02:21:21.300 | I'm familiar with prolactin from a variety of perspectives,

02:21:25.220 | but I always think of dopamine and prolactin

02:21:28.740 | as kind of a seesaw relationship.

02:21:30.880 | Dopamine's up, prolactin is down.

02:21:32.960 | Dopamine is elevated with sexual desire, sexual activity,

02:21:35.640 | post-ejaculation.

02:21:37.180 | Prolactin goes up, sets perhaps the refractory period

02:21:40.680 | on erection and ejaculation for some period of time.

02:21:43.200 | Then dopamine comes back up.

02:21:44.360 | But you know, this kind of thing.

02:21:45.720 | And I realize that's far too simplistic,

02:21:47.260 | that prolactin is doing many things

02:21:48.660 | in the brain and body besides that.

02:21:51.040 | But how often do you see hyperprolactinemias,

02:21:54.240 | I don't know if plural, prolimias is clinically correct,

02:22:00.140 | but elevated levels of prolactin

02:22:02.380 | that are causing problems for men.

02:22:06.960 | What are some of the telltale signs of that?

02:22:09.900 | And this I'd like to use as a segue

02:22:12.500 | to talking about some of the sexual dysfunction

02:22:14.860 | that is commonly discussed around the use of SSRIs

02:22:17.800 | and other drugs to treat depression

02:22:20.360 | and mental health issues that sometimes create endocrine

02:22:24.200 | and/or sexual health issues.

02:22:27.460 | - Yeah, so prolactin is sometimes,

02:22:31.380 | it's a diagnosis, hyperprolactinemia is a diagnosis,

02:22:34.280 | maybe not that many times.

02:22:35.440 | I would say less than 1% of the patients that we see

02:22:38.880 | will end up having that.

02:22:39.840 | But usually it's a handful of times a year

02:22:41.640 | 'cause we see a lot of patients.

02:22:44.160 | Typically the telltale sort of symptoms

02:22:46.880 | would be ones of low testosterone, that's a common one.

02:22:50.460 | But in my practice, I see it a lot

02:22:52.200 | with very low sperm production.

02:22:53.920 | So I've diagnosed several prolactin secreting tumors

02:22:57.300 | and the manifestation of that was,

02:22:59.480 | they weren't getting pregnant.

02:23:00.500 | We checked the sperm count, it was very low.

02:23:02.880 | That mandates a check of testosterone,

02:23:04.560 | which is also very low.

02:23:06.100 | And then that leads to a prolactin, which is very high.

02:23:08.040 | And then that was diagnosed.

02:23:10.380 | So it's something I think to be aware of,

02:23:12.660 | but I don't know that there's not usually a lot of symptoms

02:23:14.880 | and sort of going to a clinician

02:23:16.920 | when you're having sexual dysfunction,

02:23:19.440 | symptoms of low testosterone or fertility problems

02:23:22.340 | will usually be able to diagnose if it's present.

02:23:24.840 | - Are there any other hormones in the galaxy

02:23:29.080 | of sexual health related hormones that fall into

02:23:33.680 | common clinical practice for you?

02:23:39.240 | - I check estrogen as well.

02:23:40.580 | So I think that's another one.

02:23:41.580 | It's again, because of the relationship with obesity,

02:23:43.960 | I think that can be important.

02:23:44.960 | Sometimes there's too much aromatization.

02:23:47.080 | And so sometimes that can be a problem.

02:23:50.080 | I think just like we talked about normal,

02:23:51.880 | estrogen signaling is important.

02:23:53.000 | I think too much can be bad.

02:23:54.580 | So there are some men where we do see manifestations

02:23:56.520 | that it can manifest as gynecomastia in some cases.

02:23:58.880 | - Male breast tissue.

02:23:59.720 | - Male breast tissue, yeah.

02:24:01.260 | - As I was told, what was it?

02:24:04.300 | That the male breast tissue is sort of like the appendix.

02:24:08.400 | It's there, but it's not very interesting.

02:24:10.840 | - Right, right, yeah.

02:24:11.680 | Everybody has some and we just don't want the growth

02:24:13.960 | to get out of control.

02:24:14.880 | - Could you tell us about one of the world's

02:24:16.800 | most difficult to pronounce words, which is varicocele?

02:24:20.520 | - Yes, so varicocele, it's a very common condition.

02:24:24.280 | Probably about 15% of all men have it.

02:24:26.080 | And it's a very common cause of infertility.

02:24:28.400 | If you look at all the etiologies, it can be 30 to 40%.

02:24:31.800 | So basically what it is is dilated veins in the scrotum.

02:24:34.820 | So obviously we need veins to get blood

02:24:36.300 | out of the testicles.

02:24:37.640 | But sometimes they can be a little larger than average.

02:24:39.840 | And there's sort of a normal sort of thermal regulation.

02:24:42.360 | So if the veins get too big,

02:24:43.800 | it's thought to warm up the testicle.

02:24:45.800 | The other thought is that it doesn't adequately clear

02:24:47.940 | some of the metabolites.

02:24:49.880 | So exactly the pathophysiology is somewhat debated,

02:24:52.760 | but I think those probably contribute.

02:24:55.120 | And it's something that everybody should be evaluated for

02:24:57.320 | if you're concerned about fertility.

02:24:59.100 | So again, we see it very commonly.

02:25:00.880 | Given the fact that a lot of men have it,

02:25:03.660 | about one in seven men have it,

02:25:04.880 | it doesn't always cause a problem,

02:25:06.000 | but maybe about 20 to 25% of the time it does.

02:25:08.600 | So men will manifest with low sperm counts, we see.

02:25:11.960 | Sometimes discomfort, ache, worse at the end of the day

02:25:15.160 | than at the beginning, worse at the activity.

02:25:16.460 | Anytime blood can pool, sometimes it stretches

02:25:18.780 | and some men feel that.

02:25:19.840 | And then in kids, sometimes it can lead

02:25:21.460 | to either stunted testicular growth

02:25:24.600 | or shrinkage of the testicle.

02:25:26.620 | It's also thought to be a progressive lesion.

02:25:28.460 | So the longer a man has it, the more damage it can do.

02:25:31.120 | It usually manifests around puberty in general.

02:25:33.960 | So it's not a concern for everybody,

02:25:35.600 | but I think certainly if couples

02:25:36.880 | are having difficulty conceiving,

02:25:38.420 | you're having discomfort in the area and you have one,

02:25:40.840 | it's a discussion you should have.

02:25:42.480 | - What about Peyronie's disease?

02:25:45.640 | - Yeah, so Peyronie's is a scarring of the penis,

02:25:47.920 | which leads to curvature or deformity.

02:25:50.360 | So the way erections work is everything swells.

02:25:52.920 | And you can imagine if there's a scar tissue,

02:25:54.500 | it doesn't swell symmetrically.

02:25:55.660 | So you'll get like a curvature deviation.

02:25:57.440 | Sometimes you can get an hourglass or sort of a banding.

02:26:00.200 | If you look it up on the internet,

02:26:02.280 | you can see a host of different deformities that men get.

02:26:05.640 | It's probably present in about five to 10% of men.

02:26:08.440 | So it's very common.

02:26:10.400 | Sometimes it could be from injury,

02:26:12.240 | from like a penile fracture or other sort of less severe form

02:26:17.240 | of injury to the penis.

02:26:19.520 | Sometimes men have described hitting it on different things.

02:26:21.840 | Potentially that could lead to it.

02:26:24.000 | Sometimes it can manifest after prostate cancer surgery

02:26:29.000 | or other kinds of surgeries, which can sort of stun the penis

02:26:32.320 | or injure some of the nerves of the penis.

02:26:35.200 | So that's another condition we see commonly.

02:26:37.400 | Obviously it can lead to bother.

02:26:40.680 | And erections are not straight.

02:26:42.040 | That can just cause a psychological bother to men.

02:26:46.680 | It can also physically make it difficult

02:26:48.760 | for a man to have sex.

02:26:50.080 | Sometimes it can limit certain positions.

02:26:52.640 | So that's another common complaint we see.

02:26:55.260 | I think it's something that men should be aware of.

02:26:57.080 | There's now awareness campaigns.

02:26:58.460 | Now there's an FDA-approved medicine for it,

02:27:00.960 | collagenase or Xioflex,

02:27:02.300 | which is a medicine that dissolves scar tissue.

02:27:05.160 | So that's one of the treatments we have for it.

02:27:07.380 | There's also different devices, sort of stretching devices,

02:27:10.740 | where we try and just mechanically remodel the penis

02:27:13.780 | to allow it to be a little bit straighter.

02:27:15.780 | And then there's also surgical options too.

02:27:18.000 | So there's a lot we can do.

02:27:19.780 | I always tell men again, as long as you have a penis,

02:27:21.780 | we can make it hard, but we can also make it straight.

02:27:26.580 | - I'm wondering why in the study about penis length,

02:27:29.640 | testicular size and volume wasn't also measured.

02:27:34.280 | And that's something that we haven't discussed.

02:27:36.600 | What is the relationship between testicular size and volume

02:27:41.000 | and some of the other parameters we've been talking about?

02:27:43.900 | And maybe this is also a good time to highlight

02:27:46.200 | any kind of morphological signals

02:27:51.040 | that would warrant people coming to the clinic.

02:27:54.360 | So asymmetry in testicle size, for instance,

02:27:57.680 | changes in testicular size, obviously a pea-sized lump

02:28:02.080 | they taught us in high school is a warning sign

02:28:05.780 | of potential testicular tumor or cancer.

02:28:08.560 | We didn't really talk about testicles.

02:28:12.620 | - Yeah, so I think that kind of being aware,

02:28:14.580 | the average size of a testicle for a man is about,

02:28:19.040 | it's sort of about a walnut.

02:28:20.200 | So it's about 16 to 20 CCs.

02:28:23.460 | Usually if you were gonna measure it,

02:28:24.840 | it'd be about four to four and a half centimeters

02:28:27.360 | and longest axis to give your listeners

02:28:30.780 | or viewers some idea.

02:28:32.840 | If it changes, certainly let people know.

02:28:34.440 | If you feel anything, let people know.

02:28:35.700 | Although our national guidelines on screening practices

02:28:40.700 | recommends against regular testicular self-exams,

02:28:44.760 | interestingly, because I think the concern

02:28:46.920 | is that it leads to more anxiety

02:28:48.680 | than cancers that it would diagnose.

02:28:50.600 | But I think, I always tell men,

02:28:52.200 | no one knows your scrotum better than you.

02:28:53.640 | So if you identify a problem,

02:28:55.640 | you should bring it to attention.

02:28:56.700 | So the classic appearance or the way

02:28:59.660 | that a testis cancer manifests is a firm painless mass

02:29:03.640 | that you kind of feel coming from the testicle.

02:29:06.800 | - I find it interesting that, at least as I understand,

02:29:10.540 | women are encouraged to do regular self-exams

02:29:13.060 | of their breasts for lumps.

02:29:15.000 | But you're telling me that men are actually discouraged

02:29:17.320 | from doing regular exams of their testicles

02:29:19.540 | for lumps that could be cancer.

02:29:21.040 | That feels like a unfair asymmetry.

02:29:24.480 | It does, I mean, cancer, I mean,

02:29:28.120 | both seem very important.

02:29:30.380 | - Oh yeah, well, I think there's no question,

02:29:31.840 | obviously, I'm very biased.

02:29:32.920 | - Yeah, yeah, I was trying to say it

02:29:34.280 | so you didn't have to, right?

02:29:35.480 | - Oh yeah, I don't want to get in trouble

02:29:36.880 | with the US preventative services task force.

02:29:37.700 | - I mean, I don't want anyone to get cancer.

02:29:39.980 | I mean, so I don't even want a dog to get cancer.

02:29:42.900 | So I'm surprised that they discourage self-exam.

02:29:47.440 | But is it because men are getting it wrong?

02:29:50.080 | They're coming into the clinic

02:29:51.040 | thinking they have testicular cancer

02:29:52.520 | and then most of the time they don't?

02:29:54.360 | - I think that's the concern that, you know,

02:29:56.000 | the number of cancers that are diagnosed

02:29:57.980 | versus the false lumps that they identify

02:30:02.980 | just lead to more anxiety

02:30:05.840 | and end up not actually causing more harm than good,

02:30:08.660 | I think is the concern.

02:30:09.680 | But yeah, it was a surprising recommendation

02:30:12.400 | when it came down.

02:30:13.480 | Usually if patients ask about it,

02:30:14.680 | I certainly don't discourage them from doing these exams.

02:30:16.960 | And I have, we've certainly identified cancers

02:30:19.040 | through that means before.

02:30:20.600 | - Well, I saw the episode of ER

02:30:21.920 | where the guy was having trouble breathing

02:30:23.560 | when he was an elite runner

02:30:24.720 | and it turned out he had testicular cancer

02:30:26.520 | and he had overlooked the lump on his testicle.

02:30:28.680 | So I'm going to continue to self screen.

02:30:30.840 | - Okay, fair enough.

02:30:31.840 | - Numerous times today,

02:30:33.620 | we've talked about the potential benefit

02:30:35.700 | of getting a blood test for hormone profiles, lipid profiles

02:30:38.940 | and other things, as well as a sperm analysis.

02:30:41.240 | My understanding is that one can only do that

02:30:45.520 | if they have the disposable income

02:30:47.760 | to elect to do that through some commercial online service.

02:30:51.180 | But is there any way that patients who have insurance

02:30:57.120 | can approach their physician

02:30:59.360 | in a way that this would be covered by insurance?

02:31:02.560 | I don't want to get you into any trouble here,

02:31:04.320 | but you know, it's always such a shame.

02:31:07.620 | It is such a shame when we're talking about something

02:31:10.680 | that is really pervasively related to health

02:31:16.380 | as is sexual health, reproductive health.

02:31:18.580 | And people are not aware of a potential problem

02:31:22.420 | in the present or in the future

02:31:23.800 | that could have been mitigated

02:31:25.080 | simply because they didn't get a blood test

02:31:27.800 | or do something as simple as a sperm analysis.

02:31:30.960 | So we can't be presumptuous in saying,

02:31:35.000 | "Oh, well, you know, $200 or $1,000, no big deal."

02:31:38.140 | I mean, for a lot of people, that's a huge deal.

02:31:40.300 | It's prohibitive for many people.

02:31:42.780 | So how can people get this stuff assessed?

02:31:46.560 | Should they talk to their primary care physician?

02:31:48.640 | Should they call a urologist?

02:31:50.720 | What's the best approach?

02:31:52.120 | - Yeah, I think both are good strategies.

02:31:53.520 | I think, you know, insurance is becoming a lot more open

02:31:56.440 | to covering some infertility, at least testing,

02:31:58.740 | sometimes treatment as well.

02:31:59.820 | So I think a lot of insurance does cover that now.

02:32:02.440 | You know, sometimes we check semen analyses

02:32:04.600 | for other jacketory issues.

02:32:06.580 | But I think that, you know, again,

02:32:09.200 | as more of this data gets out,

02:32:10.480 | I think as more recognition how important the mail is,

02:32:12.620 | I think we'll get sort of more buy-in and coverage.

02:32:15.540 | Obviously, women have, you know,

02:32:16.860 | the automatic feedback of obituary cycles.

02:32:19.300 | So they kind of know if there's a problem,

02:32:21.980 | they can bring that to the attention.

02:32:23.180 | But men don't have that feedback

02:32:24.900 | without some of these testing.

02:32:26.660 | - Yeah, and we probably should have mentioned this earlier.

02:32:28.420 | So forgive me, this was on me to mention that

02:32:31.180 | when we talk about sperm quality

02:32:33.060 | and we sort of shifted back and forth to semen quality,

02:32:35.500 | it's possible to have normal semen volume

02:32:40.140 | and have very low sperm count, right?

02:32:41.860 | We're not talking about

02:32:42.700 | the total amount of ejaculate per se.

02:32:44.420 | We're talking about the density of forwardly motile,

02:32:47.420 | healthy, non-DNA fragmented sperm in that semen, right?

02:32:51.580 | So in other words, it's not sufficient to just assume

02:32:56.020 | because you can ejaculate that your sperm are healthy.

02:32:59.580 | - That's exactly right.

02:33:00.420 | Yeah, I mean, I think, you know,

02:33:01.380 | about 15% of men have low semen quality,

02:33:03.660 | whether it be concentration, movement, shape.

02:33:06.940 | About 1% of men have no sperm in the ejaculate.

02:33:09.180 | And that's something sometimes they have no idea about.

02:33:11.340 | So the only way to know

02:33:12.260 | would be to actually do a formal test.

02:33:14.300 | - Well, I'm encouraging people

02:33:16.020 | to get these parameters assessed.

02:33:17.980 | And I'm making that statement

02:33:20.680 | because it's very clear based on everything

02:33:23.120 | that you've told us today

02:33:23.980 | that sperm quality and hormone levels

02:33:27.720 | are just oh so important,

02:33:29.580 | not just for sexual health, but for urinary health

02:33:33.880 | and for reflecting prostate health

02:33:37.020 | and other aspects of whole body health.

02:33:38.820 | And sexual health relates directly to mental health, right?

02:33:42.660 | Now, we didn't talk so much about the psychogenic issues,

02:33:44.980 | but the two go hand in hand, exactly.

02:33:48.500 | I wanted to thank you so much for coming here today

02:33:51.540 | and sharing so much knowledge with us.

02:33:53.580 | I mean, these really are the issues

02:33:55.000 | that males think about and wonder about

02:33:59.020 | and have questions about.

02:34:01.180 | And they do so to varying degrees,

02:34:05.080 | depending on where they're at in life.

02:34:07.220 | But I think especially for younger men who are hearing this,

02:34:12.220 | who are not at the point where they want to conceive,

02:34:15.260 | it's really important to start thinking about these issues

02:34:17.340 | for all the reasons you mentioned.

02:34:18.740 | I think these issues are really important

02:34:20.980 | for women to know about as well,

02:34:22.980 | just as it's important for men

02:34:24.460 | to understand female reproductive health

02:34:27.380 | and to not just improve communication,

02:34:30.180 | but this after all is at the heart of the presence

02:34:34.220 | and proliferation of our species.

02:34:35.740 | So thanks for taking care of the male half

02:34:38.140 | and thanks for doing the work you do, it's incredible.

02:34:42.260 | The large scale studies,

02:34:43.340 | the more detailed studies on smaller populations,

02:34:48.140 | you asked the questions that it seems many people

02:34:51.460 | are just afraid to ask and you get right in there

02:34:55.020 | and come out with the really rigorous data and answer.

02:34:58.220 | So thank you so much for what you do.

02:35:00.140 | - My pleasure, thank you.

02:35:00.960 | Thank you for highlighting men's reproductive health.

02:35:03.620 | - Thank you for joining me for today's discussion

02:35:05.440 | with Dr. Michael Eisenberg.

02:35:07.120 | To learn more about his research and his clinical practice,

02:35:10.340 | please check out the links in the show note captions.

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02:35:43.440 | Not during today's episode,

02:35:44.560 | but on many previous episodes of the Huberman Lab Podcast,

02:35:47.340 | we discuss supplements.

02:35:48.580 | While supplements aren't necessary for everybody,

02:35:50.760 | many people derive tremendous benefit from them

02:35:53.080 | for things like enhancing sleep, hormone support,

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02:35:57.180 | If you'd like to learn more about the supplements discussed

02:35:59.060 | on the Huberman Lab Podcast,

02:36:00.540 | you can go to Live Momentus, spelled O-U-S,

02:36:03.100 | so livemomentus.com/huberman.

02:36:06.280 | If you're not already following me on social media,

02:36:08.160 | it's Huberman Lab on all social media platforms.

02:36:10.860 | So that's Instagram, Twitter, now called X,

02:36:13.980 | Threads, Facebook, LinkedIn.

02:36:15.500 | And on all those places,

02:36:16.700 | I discuss science and science-related tools,

02:36:18.660 | some of which overlaps with the content

02:36:20.140 | of the Huberman Lab Podcast,

02:36:21.560 | but much of which is distinct from the content

02:36:23.460 | on the Huberman Lab Podcast.

02:36:24.660 | So again, it's Huberman Lab on all social media platforms.

02:36:28.080 | If you haven't already subscribed

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02:36:31.500 | the Neural Network Newsletter is a completely

02:36:33.260 | zero cost newsletter that gives you podcast summaries,

02:36:36.500 | as well as toolkits in the form of brief PDFs.

02:36:39.140 | We've had toolkits related to optimizing sleep,

02:36:42.380 | to regulating dopamine, deliberate cold exposure, fitness,

02:36:46.060 | mental health, learning, and neuroplasticity, and much more.

02:36:49.620 | Again, it's completely zero cost to sign up.

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02:36:57.020 | I should emphasize that we do not share your email

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02:37:00.460 | Thank you once again for joining me

02:37:01.740 | for today's discussion with Dr. Michael Eisenberg.

02:37:04.380 | And last, but certainly not least,

02:37:06.620 | thank you for your interest in science.

02:37:08.320 | (upbeat music)

02:37:10.900 | (upbeat music)

Dr. Michael Eisenberg: Improving Male Sexual Health, Function & Fertility

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