How to Control Your Metabolism by Thyroid & Growth Hormone

00:00:00.000 | [upbeat music]

00:00:00.840 | - Welcome to the Huberman Lab Podcast,

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

00:00:04.900 | for everyday life.

00:00:05.920 | I'm Andrew Huberman, and I'm a professor of neurobiology

00:00:12.260 | and ophthalmology at Stanford School of Medicine.

00:00:15.660 | This podcast is separate from my teaching

00:00:17.400 | and research roles at Stanford.

00:00:19.060 | It is, however, part of my desire and effort

00:00:21.060 | to bring zero cost to consumer information

00:00:23.100 | about science and science-related tools

00:00:25.340 | to the general public.

00:00:26.960 | In keeping with that theme,

00:00:28.220 | I'd like to thank the sponsors of today's podcast.

00:00:31.240 | Our first sponsor is Four Sigmatic.

00:00:33.540 | Four Sigmatic is a wellness company

00:00:36.460 | that makes mushroom coffee.

00:00:38.060 | And if you're asking yourself,

00:00:39.200 | why would you want to put mushrooms in coffee?

00:00:41.380 | First of all, let me tell you,

00:00:42.360 | these are not psychedelic mushrooms,

00:00:44.480 | and no, the coffee doesn't taste like mushrooms.

00:00:47.040 | The coffee is delicious,

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00:01:01.100 | The two kinds of mushrooms that are in Four Sigmatic coffee

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00:01:20.640 | as well as have some effect at offsetting cognitive decline.

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00:06:03.180 | This month, we've been talking all about hormones,

00:06:05.720 | which are these absolutely incredible chemicals

00:06:08.840 | in our brain and body.

00:06:10.640 | They impact our entire lifespan.

00:06:13.520 | So from the time that we are in the womb,

00:06:16.080 | they're controlling the development of our brain

00:06:18.160 | and our bodies.

00:06:19.480 | After we are born, they're still controlling

00:06:22.420 | the development of our brain and bodies.

00:06:25.360 | And I did say development and that's because,

00:06:27.580 | contrary to what most people think,

00:06:29.200 | development lasts the entire lifespan.

00:06:31.980 | From the time you're conceived until the time you die,

00:06:35.040 | you are developing, you are changing

00:06:36.720 | and hormones are constantly updating and changing

00:06:40.600 | the different functions of your body.

00:06:42.680 | They have two major kinds of effects.

00:06:45.000 | One are immediate effects, so they can actually bind to

00:06:48.600 | or kind of park in parking spots on cells

00:06:50.960 | and impact all sorts of things

00:06:52.880 | like the growth of cells, et cetera.

00:06:54.840 | They also can control gene expression.

00:06:57.320 | This is the way that hormones during puberty

00:06:59.200 | control body hair growth and breast development

00:07:02.320 | and growth of muscles and limbs and height

00:07:05.120 | and all sorts of things.

00:07:06.100 | They are incredible.

00:07:07.600 | We've talked about testosterone and estrogen.

00:07:10.160 | We talked about insulin and glucagon

00:07:12.720 | and some of the other things.

00:07:14.000 | Today, we are going to talk about metabolism,

00:07:17.760 | mainly going to talk about thyroid hormone

00:07:20.640 | and growth hormone and some other related pathways.

00:07:24.280 | I'm going to explain to you the logic

00:07:26.840 | of how thyroid hormone and growth hormone work.

00:07:30.140 | It will become obvious why I've paired thyroid

00:07:33.320 | and growth hormone together in the same episode.

00:07:36.760 | And I will, of course, talk about tools that you can use

00:07:40.680 | to elevate or reduce thyroid hormone.

00:07:43.680 | There are cases where people want to reduce thyroid hormone.

00:07:46.580 | I will talk about tools that you can use

00:07:48.140 | to elevate growth hormone.

00:07:50.120 | There are rare cases where people want

00:07:51.680 | to reduce growth hormone.

00:07:52.900 | Most people are interested in increasing growth hormone.

00:07:56.360 | So today is going to be rich with information,

00:07:58.740 | rich with actionable tools.

00:08:00.980 | And as always, the idea is to spell out

00:08:04.040 | an organizational logic so you can come away

00:08:06.240 | from this episode and in fact, the entire month on hormones,

00:08:09.780 | really understanding at some level

00:08:12.200 | what these things we call hormones are and how they work.

00:08:14.920 | And that's really to arm you

00:08:16.600 | to encounter information going forward,

00:08:18.740 | whether or not it comes from me or from somebody else,

00:08:21.040 | a book or a course, someplace else online,

00:08:24.060 | to make sense of how to work

00:08:26.080 | with these incredible chemicals we call hormones.

00:08:30.000 | Before we begin to talk about thyroid and growth hormone

00:08:32.920 | and how our metabolism works

00:08:35.000 | and how to control metabolism,

00:08:37.500 | I want to answer a few questions that I received from you,

00:08:40.520 | from the audience.

00:08:42.360 | Every once in a while,

00:08:43.240 | someone will send me a quite earnest question

00:08:46.540 | about something they saw on the internet.

00:08:49.140 | And one of the things I've heard about quite a bit

00:08:52.820 | in the last couple of weeks

00:08:53.800 | is we've been talking about hormones and food intake

00:08:57.480 | and how those interact is this question of,

00:09:01.160 | are certain foods particularly good

00:09:03.880 | for certain organs of the body

00:09:06.640 | and can that be predicted

00:09:08.900 | on the basis of the shape of those foods?

00:09:12.140 | So, first of all,

00:09:13.060 | I want to acknowledge the question as a valid one

00:09:15.760 | because I see this every once in a while out there,

00:09:18.600 | people will say,

00:09:19.440 | "Well, walnuts are in the shape of the brain

00:09:21.720 | and therefore they are good for your brain."

00:09:24.420 | Or a particular fruit like the beet

00:09:27.900 | often looks like a heart and it's good for your heart.

00:09:30.840 | And I certainly invite questions of all kinds

00:09:34.400 | provided they are sincere questions.

00:09:36.160 | However, I am not aware of any science whatsoever

00:09:41.160 | supporting the idea that the shape of a given food

00:09:44.800 | or object for that matter

00:09:46.620 | is relevant to its functional role in the body

00:09:51.160 | in reference to biology.

00:09:52.480 | Now, beets contain something

00:09:54.640 | that we're going to talk about today.

00:09:55.680 | They contain a substance called arginine,

00:09:58.360 | which actually can control the dilation of blood vessels

00:10:01.540 | and arteries.

00:10:02.760 | So it has some relationship to heart and heart health.

00:10:05.720 | Walnuts contain various fatty acids that maybe,

00:10:10.840 | I want to underscore maybe,

00:10:12.160 | beneficial for certain aspects of brain health.

00:10:15.200 | But there's no evidence whatsoever

00:10:17.960 | that the shape of the food itself is relevant.

00:10:20.940 | And I think what's happened is,

00:10:22.720 | is that people have gone out there

00:10:24.880 | and found foods that contain certain substances

00:10:27.340 | like carrots and vitamin A

00:10:29.100 | or walnuts and particular fatty acids or beets and arginine.

00:10:33.920 | And they've selected the foods

00:10:36.060 | that happen to be in the shape of the thing,

00:10:38.380 | the organ that the particular substance like vitamin A

00:10:42.260 | or fatty acids and so forth might benefit or support.

00:10:46.540 | But of course, there are many, many other sources

00:10:49.340 | of these nutrients that don't come from walnuts

00:10:53.580 | or from beets or from carrots.

00:10:56.060 | And so I guess the short way to put it

00:10:58.620 | is that the idea that the shape of some food

00:11:02.360 | is an indication of whether or not that food

00:11:04.980 | would be healthy for a particular organ in the body

00:11:06.980 | is absolutely unfounded.

00:11:09.600 | I don't know of any evidence for it.

00:11:11.560 | And I'm not out to quash anybody's great love of these foods.

00:11:15.840 | I enjoy all the foods I just described,

00:11:18.000 | but the shape of things in the physical universe

00:11:21.480 | bears very little, if any relevance to the nutrients

00:11:26.480 | that it contains and therefore the organs that it supports.

00:11:31.520 | So thank you for your question.

00:11:33.360 | But if you see that out there,

00:11:35.360 | I don't even think you need to tell the person

00:11:38.620 | who's putting that information out into the world.

00:11:40.880 | I would just back away slowly.

00:11:43.600 | One other thing before we move into today's material,

00:11:46.480 | last episode, I talked about the problems with emulsifiers

00:11:51.060 | in highly processed foods

00:11:52.880 | and the way that they can strip the mucosal lining

00:11:54.980 | of the gut and they can limit the signaling of hormones

00:11:58.260 | like CCK that can signal to the brain satiety,

00:12:01.140 | the signal to stop eating.

00:12:03.260 | And then we got into a discussion

00:12:05.360 | about artificial sweeteners.

00:12:07.500 | And I threw out Stevia as an artificial sweetener

00:12:10.980 | and several people reached out to correct me

00:12:13.900 | that Stevia is not an artificial sweetener.

00:12:17.040 | It is a non-caloric sweetener and you are correct.

00:12:19.980 | I lumped artificial and non-caloric sweeteners together.

00:12:23.940 | And thanks to many of you that also sent me some references,

00:12:27.140 | it does not appear that Stevia can negatively impact

00:12:30.180 | the gut microbiome.

00:12:31.260 | It does seem unique among non-caloric sweeteners.

00:12:33.920 | There are probably others out there.

00:12:35.860 | The other thing that we discussed

00:12:37.140 | is how Stevia can lead to slight increases in blood glucose

00:12:42.120 | but can also improve insulin management just slightly,

00:12:44.920 | probably cancels to zero in terms of its impact

00:12:47.820 | on blood glucose provided it's not at concentrations

00:12:51.140 | that are super, super sweet.

00:12:53.340 | Ingestion of anything that's very sweet,

00:12:55.460 | whether or not it contains calories or not,

00:12:57.640 | artificial or not, will create an insulin response.

00:13:00.980 | In fact, just walking past a bakery

00:13:02.700 | and smelling delicious baked goods

00:13:05.180 | can increase your insulin secretion.

00:13:08.140 | And so I just want to point that out.

00:13:10.260 | Thank you for the information and the references

00:13:13.760 | that you found.

00:13:14.600 | Please send additional ones if you do find them.

00:13:16.480 | And I appreciate that you allow me to make corrections.

00:13:19.440 | Every once in a while I misspeak here

00:13:21.640 | and the opportunity to make corrections

00:13:23.080 | keeps us all on the same page.

00:13:24.740 | And please do keep any feedback that you have

00:13:26.980 | about particular things I cover here coming my way.

00:13:29.760 | There is so much interest in metabolism.

00:13:33.680 | We hear about having a high or a low metabolism.

00:13:36.820 | There are some people out there

00:13:38.860 | who would like to reduce their metabolism.

00:13:41.160 | They simply can't eat enough to maintain their weight.

00:13:44.280 | Most people, however, struggle with the opposite issue.

00:13:47.800 | They struggle to maintain a healthy weight

00:13:50.420 | and/or their metabolism is too low.

00:13:53.060 | Now, there are a variety of reasons

00:13:54.460 | why metabolism can be low.

00:13:56.160 | Today, we are going to talk about two hormones,

00:13:59.220 | thyroid hormone and its related pathways

00:14:02.420 | and growth hormone and its related pathways,

00:14:05.740 | which arguably are the two hormones

00:14:08.540 | and two systems in the body that are most significant

00:14:12.060 | for setting your overall level of metabolism.

00:14:15.040 | Before we dive into those,

00:14:17.260 | I just want to cover a little bit of what metabolism is.

00:14:20.860 | And I want to talk about which organs in your body

00:14:23.920 | use the most energy.

00:14:25.340 | So metabolism is the consumption of energy,

00:14:28.480 | not necessarily eating,

00:14:29.820 | but it's the use of energy in the cells of the body

00:14:34.060 | for growth of tissues, for repair of tissues,

00:14:37.480 | and also just for day-to-day maintenance of function.

00:14:41.780 | A good example of maintenance of function

00:14:43.420 | would be your brain.

00:14:44.700 | Most of your metabolic needs,

00:14:46.820 | your so-called basal or resting metabolic needs

00:14:49.900 | are for your brain, for thinking.

00:14:52.800 | If you were to just sit in a bed all day

00:14:54.680 | and do nothing but think,

00:14:56.780 | that consumes about 75% of your metabolic needs.

00:15:01.540 | Now, there's also moving around.

00:15:03.820 | If you have a job that requires a lot of heavy labor

00:15:07.540 | or lifting things, or you're a new parent

00:15:09.400 | and you're carrying kids around

00:15:10.500 | and you're going up and down the stairs

00:15:11.620 | or back and forth to the refrigerator for formula, et cetera,

00:15:16.060 | well, then you're burning more energy,

00:15:17.700 | burning more calories.

00:15:18.760 | But even if you are very physically active,

00:15:21.420 | unless you're an ultra marathoner or a marathoner,

00:15:23.940 | chances are that 75% of your metabolic needs

00:15:27.700 | are coming just from your brain.

00:15:29.540 | And that's because neurons consume a lot of energy.

00:15:32.340 | Neurons, of course, are just the nerve cells of your brain.

00:15:35.220 | So these two hormones, thyroid hormone and growth hormone,

00:15:39.660 | we think of as related to metabolism of things in the body,

00:15:42.900 | keeping body fat low and keeping muscles strong

00:15:45.940 | and tendons strong and repairing themselves, et cetera.

00:15:48.780 | But they are also key for brain function,

00:15:51.980 | for the ability to maintain cognitive function

00:15:54.200 | throughout the lifespan.

00:15:55.780 | So the big theme I'd like to introduce

00:15:58.960 | is that metabolism isn't just about losing weight,

00:16:03.360 | but having a high metabolism,

00:16:04.900 | provided it's not too high, is great.

00:16:06.620 | It means that you will have more lean tissue,

00:16:08.560 | more bone and muscle and less adipose tissue, fat.

00:16:12.120 | And we know that that's healthy.

00:16:14.080 | How much fat and how much muscle?

00:16:16.320 | Well, that varies and the numbers on this

00:16:18.040 | are always shifting.

00:16:19.200 | But in general, muscle and its related tissues

00:16:24.200 | burns more energy than does adipose tissue or fat.

00:16:28.820 | And the water in your body doesn't consume any energy.

00:16:31.420 | So metabolism can be increased

00:16:33.980 | simply by adding muscle to your body

00:16:36.340 | and reducing fat or adjusting the ratio of the two.

00:16:39.500 | But regardless,

00:16:40.340 | even if you're not interested in changing body composition,

00:16:43.700 | these two hormones, thyroid hormone and growth hormone

00:16:46.140 | are super important for metabolism of all kinds,

00:16:49.520 | including tissue repair after injury,

00:16:51.860 | including maintaining cognitive function and wellbeing

00:16:54.680 | and the ability to think clearly as you age,

00:16:56.660 | offsetting dementia and so forth.

00:16:58.680 | So the big theme here

00:17:00.620 | really includes the previous episodes.

00:17:04.020 | You don't have to have seen those episodes,

00:17:06.020 | but for the last three episodes and today as well,

00:17:09.100 | we've been talking about hormones,

00:17:10.440 | these substances that are released

00:17:11.660 | from one location in the body

00:17:12.700 | that go and act other locations in the body.

00:17:15.140 | I'm going to tell you how that works

00:17:16.260 | for thyroid and growth hormone.

00:17:17.860 | But now that you've heard about testosterone and estrogen

00:17:20.580 | and you're going to hear about thyroid and growth hormone,

00:17:24.000 | I want you to realize that there's a repeating logic.

00:17:29.000 | First of all, there are neurons in your brain

00:17:31.540 | in an area called the hypothalamus,

00:17:33.980 | which it just means it's below the thalamus hypo.

00:17:36.160 | It sits at the base of your brain in the front,

00:17:38.020 | it's part of the forebrain.

00:17:39.320 | So it's more or less above the roof of your mouth,

00:17:41.160 | maybe about a centimeter or so,

00:17:42.980 | and then about a centimeter forward in most people.

00:17:46.020 | And neurons in the hypothalamus

00:17:49.420 | release hormones that are called releasing hormones.

00:17:54.260 | So we've talked in previous episodes about, for instance,

00:17:58.020 | gonadotropin-releasing hormone.

00:18:00.580 | So those are little neurons that then signal

00:18:03.140 | another brain area called the pituitary

00:18:05.260 | to release other hormones.

00:18:06.860 | Today, we're going to see this again.

00:18:09.040 | In the brain, you have neurons that release

00:18:13.740 | thyrotropin or thyroid-releasing hormone.

00:18:17.580 | You also have growth hormone-releasing hormone.

00:18:19.780 | So anytime you hear releasing,

00:18:21.740 | chances are those are neurons that are in your brain

00:18:25.180 | and they extend little wires we call axons

00:18:27.220 | into your pituitary.

00:18:28.540 | And the pituitary releases a bunch of hormones

00:18:31.380 | into the bloodstream and the pituitary releases things

00:18:34.380 | that most often have the name of stimulating hormone

00:18:37.540 | because they stimulate organs.

00:18:39.660 | So in keeping with the theme of thyroid hormone,

00:18:42.420 | you have thyroid-releasing hormone in the brain,

00:18:45.500 | tells the pituitary to release thyroid-stimulating hormone.

00:18:49.740 | And then the thyroid, which we'll talk about in a moment,

00:18:52.540 | releases thyroid hormones.

00:18:54.420 | In the testosterone and estrogen episode,

00:18:56.980 | we talked about how you have

00:18:57.800 | gonadotropin-releasing hormone.

00:18:59.500 | There's the releasing again up in the brain,

00:19:01.340 | remember, releasing hormone comes from the brain.

00:19:04.060 | Then you had things like luteinizing hormone

00:19:06.420 | and follicle-stimulating hormone,

00:19:08.020 | which were in the pituitary,

00:19:09.360 | and those traveled to the ovaries or the testes

00:19:11.540 | and acted on those tissues, okay?

00:19:13.700 | So please try and embed this logic.

00:19:16.700 | If you hear the word releasing hormone,

00:19:18.500 | it's coming from the brain,

00:19:20.120 | and that makes it actionable in certain ways

00:19:22.580 | that we'll return to later.

00:19:24.580 | In addition, the pituitary is letting go

00:19:27.740 | of all these hormones into the bloodstream

00:19:29.340 | that are stimulating different tissues.

00:19:31.460 | So for thyroid, it's thyroid-stimulating hormone,

00:19:34.660 | and then it goes to the thyroid.

00:19:35.860 | And the thyroid is a little butterfly-shaped gland

00:19:39.160 | that's right around the Adam's apple.

00:19:41.200 | If you want to see yours,

00:19:42.840 | not directly 'cause it's got skin over it,

00:19:44.760 | what you would do is you'd take a sip of water,

00:19:47.080 | you'd look in the mirror, and you'd swallow.

00:19:50.080 | And the thing that moves up and down, that is your thyroid.

00:19:54.180 | Now, some people call it your Adam's apple

00:19:56.100 | because it sits right near this protrusion in the trachea,

00:19:59.780 | which is the Adam's apple.

00:20:01.620 | No matter whether or not you're male, female,

00:20:04.320 | or regardless of what your chromosomal background is,

00:20:06.500 | everyone has an Adam's apple.

00:20:08.420 | It tends to be more pronounced in people

00:20:10.060 | that got a surge of testosterone early in development

00:20:12.340 | because it has a testosterone sensitivity to it,

00:20:15.620 | and that actually controls the timbre,

00:20:17.700 | the so-called deepness of the voice.

00:20:20.180 | So the thyroid gland sits right there,

00:20:23.540 | and it's got four little bumps behind it

00:20:25.520 | called the parathyroid gland,

00:20:26.980 | and it releases two hormones into the blood

00:20:30.460 | to stimulate different tissues and their metabolism,

00:20:32.780 | and those hormones are called T4 and T3.

00:20:35.380 | So if this is already sounding like a lot of information,

00:20:37.700 | it's really easy, I promise.

00:20:40.020 | Releasing hormone comes from the brain,

00:20:42.480 | stimulating hormone comes from the pituitary,

00:20:44.560 | and in this case, we're talking about the thyroid

00:20:47.220 | binding up that stimulating hormone and saying,

00:20:49.620 | "Oh, I need to release something,"

00:20:50.940 | and it releases T4 and T3.

00:20:52.380 | And guess what?

00:20:53.220 | You can basically forget about T4.

00:20:54.940 | T4, it's not completely inactive, it has some roles,

00:20:58.100 | but T3 is the one that's more or less active.

00:21:00.840 | Now, what does thyroid hormone do?

00:21:03.980 | A lot of people think, "Oh, thyroid, it's like metabolism,

00:21:06.560 | and people who are hypothyroid

00:21:07.780 | all have bulging eyes and are real thin,

00:21:09.580 | and people who have hypothyroid are overweight,

00:21:11.840 | and their eyes are half closed or something."

00:21:16.380 | And indeed, thyroid hormone controls

00:21:18.780 | a lot of the features of the face and the eyes,

00:21:20.840 | and it can control amounts of adipose tissue and so forth.

00:21:25.120 | But the main role of thyroid hormone, of T3,

00:21:30.120 | is to promote metabolism.

00:21:32.840 | And that doesn't just mean the consumption of energy,

00:21:35.920 | it means the utilization of energy,

00:21:37.840 | including the buildup of tissues.

00:21:40.240 | So it acts on all sorts of target tissues in the body.

00:21:43.680 | It acts on muscle, it acts on the liver,

00:21:47.340 | it acts on the cartilage, it acts on the bone.

00:21:51.060 | And it's not just involved in using energy,

00:21:53.420 | it's also converting energy.

00:21:54.980 | I do realize I said that twice.

00:21:56.740 | It's involved in taking fats

00:21:58.740 | and breaking them down into fatty acids

00:22:00.980 | and converting those into ATP,

00:22:03.440 | which is an important thing for cells to use energy.

00:22:07.760 | It's also involved in taking sugars

00:22:10.180 | and turning those into energy.

00:22:12.100 | And yes, it goes to adipose tissue, to fat.

00:22:15.560 | We have different kinds of fat that we'll talk about today,

00:22:17.440 | but it goes to white fat

00:22:18.520 | and it liberates or helps liberate some of the fats

00:22:21.920 | from those fat cells and use them for energy.

00:22:25.600 | And this is why higher thyroid

00:22:26.960 | is associated with leaner bodies.

00:22:29.360 | Lower thyroid is associated with less lean bodies.

00:22:33.400 | So one thing that's absolutely key and is actionable,

00:22:37.580 | we're right there already in discussing tools, is iodine.

00:22:42.360 | Iodine comes from things in the ocean, right?

00:22:47.300 | And here are a couple of interesting facts about iodine.

00:22:50.160 | And then we'll talk about whether or not

00:22:51.620 | you should be supplementing iodine or not.

00:22:54.960 | First of all, iodine is most common in sea salt,

00:22:59.960 | in kelp and in seaweed.

00:23:04.040 | And most people can get enough iodine

00:23:06.960 | from the food they eat and/or the table salt they consume.

00:23:11.840 | Almost all table salt from all over the world,

00:23:14.600 | regardless of where you are, contains iodine.

00:23:17.060 | The thyroid needs iodine in order to produce thyroid hormone

00:23:22.960 | and you need sufficient levels of thyroid hormone.

00:23:24.960 | Not too much, but you need it.

00:23:27.180 | So chances are you are getting enough iodine,

00:23:30.540 | although you might not,

00:23:32.160 | especially those of you following a particularly

00:23:34.560 | quote unquote clean diet might not be getting enough iodine.

00:23:38.320 | Here's the deal with iodine.

00:23:39.720 | Iodine combines with an amino acid

00:23:42.320 | that we've talked about before called L-tyrosine.

00:23:45.400 | L-tyrosine comes from meat, from nuts.

00:23:47.680 | There are some plant-based sources as well.

00:23:49.840 | It is the precursor to dopamine.

00:23:52.720 | But in the thyroid, iodine combines or works with L-tyrosine

00:23:57.720 | to produce T3 and T4, the thyroid hormone.

00:24:01.220 | So you absolutely need sufficient iodine.

00:24:04.440 | You need sufficient L-tyrosine.

00:24:06.880 | And then you also need something else,

00:24:08.200 | which is called selenium.

00:24:09.220 | And we'll talk about selenium in a moment.

00:24:11.740 | So there's a condition

00:24:14.080 | that shows up in little pockets in the world.

00:24:16.440 | It's not super common, meaning it's not very widespread,

00:24:21.440 | but in certain areas that are far away from the ocean.

00:24:25.020 | At one point, this was historically

00:24:27.120 | in the Midwestern states of the United States,

00:24:30.000 | in some mountain regions of other countries,

00:24:32.520 | in some areas of Africa that were far from the ocean.

00:24:38.160 | People would get extremely swollen bulges in their necks.

00:24:42.260 | And this was called goiter.

00:24:44.520 | And the reason they were getting those swollen bulges

00:24:47.080 | is because the thyroid itself was hypertrophy.

00:24:50.660 | It was growing in an attempt to churn out more thyroid.

00:24:55.660 | And because it was getting a lot of stimulating hormone

00:25:00.480 | from the pituitary.

00:25:02.000 | But, and I don't want to go too far off track here,

00:25:05.140 | but as you recall, the brain and the pituitary

00:25:08.320 | are paying attention in a cellular sense

00:25:11.040 | to the levels of hormones in the blood.

00:25:12.920 | And when those hormones get too high,

00:25:14.740 | they shut off the stimulating hormone.

00:25:16.280 | They shut down the signal to make more,

00:25:17.740 | kind of like a thermostat.

00:25:19.020 | When the levels are too low,

00:25:20.780 | like there's not enough testosterone in the bloodstream,

00:25:22.860 | or there's not enough estrogen,

00:25:23.980 | the brain will continue to push out the signal to make more.

00:25:28.120 | Similarly, if there's not enough thyroid circulating,

00:25:31.620 | or there's not enough iodine to make thyroid,

00:25:34.240 | therefore not enough thyroid hormone circulating,

00:25:36.880 | the thyroid gland itself is not getting shut down.

00:25:40.480 | There's tons of stimulating hormone

00:25:42.060 | and releasing hormone coming from the brain,

00:25:43.460 | like release, release, release.

00:25:44.580 | And there's no way they can make thyroid hormone

00:25:46.380 | instead the gland just gets bigger and bigger and bigger.

00:25:48.340 | And so people get goiter.

00:25:49.880 | This is one of the reasons why table salt has iodine in it.

00:25:54.220 | Although there are other foods

00:25:55.180 | that have iodine in it as well.

00:25:57.420 | So how much iodine do you need?

00:26:00.340 | Well, you don't need a whole lot.

00:26:02.400 | Some people who are hypothyroidal might,

00:26:06.140 | and I want to emphasize might,

00:26:07.100 | you absolutely should talk to your doctor.

00:26:08.780 | This is a serious matter.

00:26:09.960 | Anytime you're talking about hormones

00:26:12.100 | or manipulating levels of thyroid,

00:26:13.860 | you absolutely want to talk to your doctor.

00:26:15.700 | Some people benefit from supplementing iodine.

00:26:18.340 | It is contained in most salts.

00:26:19.940 | It's in Himalayan salt, not always, but often.

00:26:23.680 | I know these days there's a lot of excitement

00:26:25.940 | about pink salts and sea salts,

00:26:27.580 | and the kind of artisan salt thing has kind of taken off

00:26:31.900 | in the foodie land, which is great.

00:26:33.420 | Some of them are actually quite tasty.

00:26:35.380 | You can just take it directly if you like the taste of salt,

00:26:39.180 | but iodine can be supplemented through things like kelp

00:26:42.280 | and seaweed and kelp tablets.

00:26:43.940 | Now, if you are hyperthyroidal, you make too much thyroid,

00:26:47.060 | that actually can be a problem.

00:26:48.780 | So really the best way to figure this out

00:26:51.280 | is to get your blood levels tested of thyroid hormone.

00:26:55.060 | But there's so much iodine in the ocean

00:26:58.980 | that believe it or not, people that live near the coast

00:27:01.520 | can actually just absorb it through the air

00:27:03.540 | just by breathing ocean air.

00:27:05.320 | So that gives you a sense of just how little iodine

00:27:08.460 | you actually need to consume in food or in salt.

00:27:10.660 | So if you're within a few miles of the ocean

00:27:12.260 | or you visit the ocean from time to time,

00:27:13.720 | you're probably getting plenty.

00:27:15.580 | It does have to come together, as I mentioned,

00:27:17.520 | with L-tyrosine, and this is why foods

00:27:20.380 | that contain L-tyrosine,

00:27:21.820 | and provided that you have sufficient iodine in your diet,

00:27:25.960 | and if you have sufficient selenium in your diet,

00:27:30.000 | does serve to increase your metabolism.

00:27:32.600 | And that is, again, is for the growth and repair of tissues.

00:27:36.860 | And that's really important.

00:27:38.560 | It's not just about keeping your metabolism high

00:27:40.520 | so that you can be on the leaner side of things

00:27:42.920 | or adjust your body weight, excuse me,

00:27:45.100 | your body composition ratios the way you like.

00:27:47.760 | Repair of injuries, repair of brain tissue,

00:27:51.040 | clearance of any damage from neurons,

00:27:52.840 | clearance of any damage to the body

00:27:55.440 | is also going to depend on thyroid.

00:27:57.180 | Again, metabolism being this kind of rate of fuel consumption

00:28:00.820 | and use in the body generally,

00:28:02.420 | not just about body mass indexes and things of that sort.

00:28:05.960 | So let's talk about selenium because it's really important.

00:28:08.780 | And even though most people are getting

00:28:10.460 | a lot of sufficient iodine

00:28:12.660 | and most people are probably getting enough L-tyrosine,

00:28:17.260 | I'm guessing most people may not be getting enough selenium

00:28:21.520 | if their goal is to increase thyroid hormone,

00:28:23.800 | at least that's what the literature says.

00:28:26.060 | Without going into the biochemistry,

00:28:28.480 | selenium is important in order for thyroid hormone

00:28:31.900 | to be made because of the way that it allows L-tyrosine

00:28:35.960 | and iodine to interact.

00:28:39.480 | And the thing is most people aren't getting enough selenium

00:28:44.120 | because they don't eat foods that are high in selenium.

00:28:46.040 | Now, how much selenium you need

00:28:47.600 | will depend on where you live.

00:28:48.880 | It actually varies country by country.

00:28:50.920 | Some countries I found say that you should get

00:28:54.640 | 100 micrograms, some say 200, some say 155.

00:28:58.560 | The average was about 155 micrograms,

00:29:00.720 | the countries I looked at.

00:29:02.340 | People who are trying to increase thyroid levels

00:29:04.740 | might want to consume more selenium.

00:29:06.960 | And if you consume a vitamin, of course,

00:29:08.500 | you want to make sure if it has selenium

00:29:11.320 | that you're not overdoing it

00:29:12.240 | by consuming a lot of selenium-rich foods either.

00:29:15.080 | But nonetheless, I think it's fair to say

00:29:17.340 | that most people probably could do well

00:29:19.920 | by ingesting slightly more selenium than they currently are,

00:29:23.020 | although, of course, always talk to your doctor.

00:29:26.220 | Brazil nuts are the heavyweight champion of foods

00:29:28.740 | to get selenium from.

00:29:30.440 | It has very high concentrations of selenium.

00:29:32.660 | In just six or eight, Brazil nuts contain

00:29:36.100 | something like 550 micrograms of selenium.

00:29:40.400 | It's also present in fish.

00:29:42.240 | So certain fish like yellowfin tuna,

00:29:44.940 | although nowadays, whenever I mentioned tuna or shellfish,

00:29:48.140 | which is the other rich source of selenium,

00:29:50.860 | people will tell me immediately there are all sorts

00:29:54.060 | of issues around farm, not farm, mercury, et cetera.

00:29:57.100 | So I've never particularly liked eating fish

00:30:00.200 | 'cause of the way it tastes.

00:30:01.600 | So that's why I avoid it.

00:30:02.740 | But for those of you that like it,

00:30:03.880 | I'm sure you're much more skilled in knowing

00:30:06.460 | which fish to buy and which fish not to buy.

00:30:08.580 | Ham, of all things, contains a lot of selenium.

00:30:12.780 | For whatever reason, pork does.

00:30:14.480 | I'm not a big consumer of pork.

00:30:16.220 | Beef has some selenium, but what's interesting,

00:30:18.740 | if you look at the sources, pork, beef, turkey, chicken,

00:30:22.360 | cottage cheese, eggs, brown rice,

00:30:25.620 | what you want to understand is that Brazil nuts,

00:30:29.020 | six to eight Brazil nuts has 550 micrograms of selenium

00:30:33.940 | and all the other foods I mentioned

00:30:36.060 | at much greater portion size than equivalent

00:30:38.660 | to six to eight Brazil nuts,

00:30:40.740 | either by volume or by calories,

00:30:43.660 | they have something like 30 to 50 micrograms of selenium.

00:30:47.540 | So if you're not eating Brazil nuts,

00:30:48.820 | and I'm guessing most people aren't,

00:30:51.400 | and you're not eating a lot of animal-based foods,

00:30:54.140 | which I know many of you aren't,

00:30:55.700 | then you're probably not getting enough selenium.

00:30:58.860 | And again, you can have these levels measured

00:31:01.300 | or you can just check what you're consuming

00:31:03.620 | and figure out whether or not you're meeting the ration

00:31:06.360 | that you need in order to get healthy levels of thyroid.

00:31:09.860 | It is present in things like mushrooms,

00:31:12.280 | but again, in a bowl of mushrooms,

00:31:15.820 | what is the equivalent to a bowl of mushrooms?

00:31:17.940 | 12 micrograms of selenium.

00:31:19.580 | And if the daily ration is something

00:31:21.180 | in the 100 to 200 range,

00:31:23.480 | again, look it up for the area you are,

00:31:25.140 | you can see really quickly why,

00:31:27.180 | even though things like mushrooms and spinach

00:31:29.180 | and milk and yogurt and lentils and cashews,

00:31:31.060 | and now we're into the vegetarian segment

00:31:33.340 | in the list that I constructed,

00:31:35.020 | you're probably not getting enough selenium.

00:31:36.740 | So it's kind of an interesting thing

00:31:38.920 | if you're an experimenter

00:31:40.360 | and you get the clearance from your doctor,

00:31:42.140 | you could try increasing your selenium levels

00:31:43.940 | and see how that impacts your metabolism.

00:31:46.060 | Again, Brazil nuts are probably going to be

00:31:48.320 | the most direct way to get sufficient selenium levels,

00:31:52.000 | but because levels are so high in Brazil nuts,

00:31:54.180 | it also means that you could overdo it as well.

00:31:56.660 | I'm not really aware of what the consequences are

00:32:00.660 | of getting too much selenium,

00:32:03.260 | although you can get too much of anything

00:32:04.940 | and I'm guessing those consequences aren't good.

00:32:07.460 | I also want to mention that for children,

00:32:10.580 | their daily requirements of selenium are much lower

00:32:13.660 | as low as 30 or 40 micrograms for kids 14 years or younger.

00:32:18.660 | And in some areas, I really want to underscore this,

00:32:21.940 | the amount of selenium that's recommended daily

00:32:25.100 | is as low as 55 micrograms.

00:32:28.060 | So it's not that you should be shooting for thousands

00:32:30.980 | or even high levels of hundreds of micrograms of selenium,

00:32:34.740 | and again, that's micrograms, not milligrams.

00:32:37.280 | So again, look into what you need,

00:32:38.600 | but if you're somebody who's interested

00:32:40.700 | in keeping thyroid function healthy and productive,

00:32:45.700 | then you certainly want to make sure

00:32:47.780 | you're getting enough iodine,

00:32:48.900 | you're getting enough selenium,

00:32:50.780 | and you're getting enough l-tyrosine.

00:32:52.580 | And it's interesting when you start looking

00:32:54.060 | at the various foods, especially highly processed foods,

00:32:56.940 | then you start to realize that perhaps many people,

00:32:59.800 | maybe you, are not.

00:33:01.500 | Not incidentally, selenium has some other effects on health

00:33:05.780 | that can be quite positive.

00:33:07.420 | And even though these don't relate to thyroid

00:33:09.160 | or growth hormone function specifically,

00:33:11.380 | I think you might want to know about them

00:33:13.260 | given that we're on the topic of selenium.

00:33:15.360 | The first is that there are three studies,

00:33:17.660 | all of which showed very high efficacy

00:33:21.340 | for reducing the risk of something called pre-eclampsia.

00:33:25.140 | Excuse me, pre-eclampsia.

00:33:27.800 | Pre-eclampsia is seizures that are related

00:33:30.800 | to blood pressure issues during

00:33:32.560 | or around the delivery of a new baby.

00:33:36.200 | And it actually, it's a rare-ish condition,

00:33:38.860 | but it actually can be quite deadly.

00:33:41.740 | And so the fact that selenium is important

00:33:44.840 | for offsetting pre-eclampsia risk is interesting.

00:33:47.800 | I don't know the exact mechanism,

00:33:49.580 | and I'm guessing there are only a few of you out there

00:33:51.460 | that are either pregnant or thinking of conceiving soon,

00:33:55.160 | but that's worth noting.

00:33:56.440 | Obviously, anything related to pregnancy or lactation,

00:33:59.540 | especially talk to your doctor.

00:34:02.040 | I'm guessing that selenium is probably

00:34:03.860 | in a lot of prenatal formulas,

00:34:05.540 | but that's one clear benefit of having sufficient selenium.

00:34:10.540 | The other is a reduced prostate cancer risk.

00:34:13.140 | There's a study showing that having sufficient selenium

00:34:16.100 | can reduce prostate cancer risk.

00:34:18.200 | And there is some evidence that if you consume foods

00:34:22.540 | from areas with soil that's low in selenium,

00:34:25.420 | that can be a problem.

00:34:26.760 | And last episode, we talked about all these issues

00:34:28.860 | related to soil quality,

00:34:31.940 | things that are making their way into food

00:34:33.320 | that are disrupting hormones and so forth.

00:34:36.020 | But having sufficient selenium from food

00:34:40.260 | could offset the low content in any soil.

00:34:43.600 | And so that apparently can reduce prostate cancer risk.

00:34:46.800 | It's a minor effect,

00:34:47.740 | but it's a statistically significant one.

00:34:50.080 | And the other one is a reduction in acne,

00:34:52.440 | which is interesting.

00:34:53.280 | I'm guessing that that probably has to do

00:34:55.680 | with the thyroid hormone pathway

00:34:57.220 | because of the way thyroid hormone can impact the liver.

00:35:01.080 | And then it turns out that the liver and various

00:35:04.780 | biochemical reactions in the liver can impact acne.

00:35:08.380 | And that's probably an episode all into itself,

00:35:10.700 | but those are just some additional benefits

00:35:13.100 | of getting sufficient selenium.

00:35:15.180 | Okay, so we're already deep into tools related

00:35:17.440 | to making sure that you have sufficient selenium,

00:35:20.920 | iodine, and L-tyrosine in order to make enough

00:35:24.220 | thyroid hormones that can support your metabolic processes

00:35:28.620 | in your liver, your muscles, your tendons,

00:35:30.460 | for whatever purpose, keeping your metabolism high,

00:35:33.660 | for body composition reasons, or for healing,

00:35:37.480 | for keeping your brain working well.

00:35:39.780 | Earlier I mentioned there are people

00:35:42.540 | who are following very clean diets.

00:35:44.680 | So these are people that consume no processed foods.

00:35:47.640 | Any starch they might eat is going to be

00:35:49.720 | maybe a rice or a grain,

00:35:51.280 | or any protein they might consume is going to be

00:35:55.620 | either from, let's hope, from humanely raised animal sources

00:35:59.980 | or maybe they're pure plant-based.

00:36:02.460 | Believe it or not, those folks are actually

00:36:06.480 | very susceptible to low iodine,

00:36:08.900 | because it turns out that diets that are very meat rich

00:36:13.720 | and don't have many vegetables,

00:36:15.300 | as well as diets that are very vegetable rich,

00:36:18.120 | but don't have many meats or salts,

00:36:21.100 | are at risk of lowering thyroid hormone

00:36:25.300 | by way of the iodine pathway and other pathways.

00:36:27.900 | And so let me try and simplify this for you.

00:36:30.700 | Chances are, if people are doing the all meat diet,

00:36:32.780 | they're not sprinkling,

00:36:33.700 | they're not wrapping those steaks in seaweed,

00:36:36.540 | and they may or may not be supplementing with iodine.

00:36:40.220 | Chances are they're probably consuming iodine salt,

00:36:43.000 | but their requirements go up

00:36:45.400 | if they're not consuming vegetables.

00:36:46.840 | People who are consuming vegetables,

00:36:48.620 | it's kind of interesting,

00:36:49.460 | we always hear that we should have

00:36:50.540 | our cruciferous vegetables, and those are so important,

00:36:53.700 | but they're actually substances, compounds,

00:36:57.020 | within high quality cruciferous vegetables

00:37:00.780 | that can interfere with thyroid hormone function.

00:37:03.660 | So if you're eating a lot of that stuff,

00:37:05.980 | a lot of cabbages, and just look up your other,

00:37:08.620 | I think broccoli is a cruciferous vegetable,

00:37:10.580 | and I won't read off the whole list,

00:37:11.900 | you could just put into the internet.

00:37:13.860 | But if you're, we're always told to eat

00:37:15.820 | a lot of the dark leafy green stuff.

00:37:18.540 | Well, unless that dark leafy green stuff is kelp or seaweed,

00:37:23.540 | chances are that we're not getting enough iodine

00:37:26.940 | unless we're adding salt to our food.

00:37:29.360 | And chances are that we may be lowering

00:37:31.780 | the total amount of thyroid that we're making,

00:37:33.900 | as well as the fact that in plant-rich diets,

00:37:37.920 | it's hard to get enough L-tyrosine.

00:37:39.700 | And I don't want, I'm not here to inflame

00:37:42.240 | any of the vegans or the carnivore folks.

00:37:45.020 | I don't take a stance either way on any of that.

00:37:47.340 | I'm just learning, trying to report the science.

00:37:49.940 | The point I want to make is your health is important.

00:37:52.700 | So if you are purely plant-based

00:37:54.700 | and you're eating a lot of cruciferous vegetables,

00:37:56.400 | make sure you're getting enough iodine.

00:37:58.200 | It does seem like the cruciferous vegetables

00:38:00.360 | can increase the need for further iodine.

00:38:03.480 | And same thing if you're purely,

00:38:05.220 | and you're on this all meat diet or your keto,

00:38:07.660 | and you're not ingesting many vegetables.

00:38:09.940 | So I always thought that the cleaner the diet, the better,

00:38:13.080 | but it turns, and probably that's true

00:38:14.980 | from the standpoint of hormone regulation,

00:38:19.240 | estrogen and testosterone and other hormones.

00:38:22.680 | The highly processed foods really are terrible.

00:38:25.460 | There's so much evidence for that.

00:38:27.040 | The phthalates in plastics and the processed foods

00:38:30.720 | and the emulsifiers,

00:38:31.640 | all the stuff we talked about previous episode.

00:38:33.840 | But it does seem to be that people

00:38:36.380 | that are not getting enough iodine for whatever reason,

00:38:40.160 | really need to check out whether or not

00:38:43.220 | their iodine levels need to be increased

00:38:45.440 | because of the fact that they're consuming so many plants

00:38:48.200 | or so many meats, and in some cases,

00:38:50.500 | plants that actually lower thyroid hormone.

00:38:52.720 | And not to beat a dead horse or cabbage,

00:38:55.420 | but there are a number of things that iodine can do

00:38:58.460 | that are positive, that are sort of,

00:39:00.960 | they're related to thyroid, not directly.

00:39:03.140 | They're kind of offshoots of the thyroid pathway.

00:39:05.580 | They're downstream of it, we would say,

00:39:07.960 | in terms of how they impact metabolic function.

00:39:10.380 | One of those is to reduce something

00:39:12.280 | called C-reactive protein.

00:39:13.880 | Some of you may have heard of CRP or C-reactive protein.

00:39:16.920 | C-reactive protein is something that you want to keep

00:39:18.960 | at modestly low levels.

00:39:20.880 | It's associated with inflammation

00:39:22.360 | and various forms of heart disease

00:39:23.840 | and even eye disease, macular degeneration.

00:39:26.580 | So it does appear that iodine supplementation

00:39:30.060 | or getting sufficient iodine from food either works,

00:39:33.680 | is associated with reduced levels of C-reactive protein

00:39:39.320 | in the blood and an anti-inflammatory effect.

00:39:41.580 | And the anti-inflammatory effect brings us back

00:39:43.960 | to our old friend interleukin-6.

00:39:45.760 | Remember, there are these inflammatory cytokines.

00:39:48.440 | They have many, many names

00:39:50.140 | because there are many, many of them.

00:39:52.000 | Interleukin-10 is the one that's anti-inflammatory.

00:39:55.280 | Interleukin-6 is the one that's inflammatory.

00:39:58.280 | Anytime you see IL-6,

00:40:00.400 | that usually means that there's an inflammatory response.

00:40:03.140 | There's a wound, there's inflammation of the brain.

00:40:06.280 | Somebody is either sleep deprived or had a brain injury,

00:40:09.120 | or they're dealing with some sort of infection.

00:40:11.960 | IL-6 is kind of a catchall for inflammation.

00:40:15.080 | And it does appear that iodine supplementation

00:40:18.040 | can reduce circulating IL-6 associated with inflammation.

00:40:22.100 | So in that sense, iodine can have

00:40:24.520 | an anti-inflammatory effect.

00:40:26.280 | So by now, it should be abundantly clear,

00:40:29.640 | if you care about thyroid hormone,

00:40:31.200 | if you care about the pathways that it impacts,

00:40:33.920 | like having a high level of metabolism,

00:40:36.480 | which I guess if for no other reason is attractive,

00:40:39.280 | 'cause then you can eat more

00:40:40.540 | and still maintain a healthy body composition,

00:40:43.740 | but also for brain health, cognitive function,

00:40:47.180 | tissue repair, all that stuff,

00:40:49.260 | keeping C-reactive protein low, keeping IL-6 low,

00:40:52.120 | make sure you're getting enough

00:40:52.960 | iodine, selenium, and L-tyrosine.

00:40:55.200 | If you're curious how thyroid actually increases metabolism,

00:40:58.520 | allows you to eat more, et cetera,

00:40:59.900 | it relates to something we covered last issue,

00:41:02.160 | which is glucose.

00:41:03.620 | Remember, when you eat something, blood sugar goes up,

00:41:05.820 | insulin is secreted from the pancreas,

00:41:08.300 | and it makes sure that blood glucose doesn't go too high,

00:41:10.420 | which can damage tissues, or too low,

00:41:12.440 | which can make you hypoglycemic.

00:41:15.140 | Thyroid increases glucose uptake by various tissues,

00:41:19.060 | in particular muscle and bone.

00:41:21.320 | It actually can increase bone mineral density,

00:41:23.680 | which is a really good thing as you get older.

00:41:26.000 | Injuries, when I say older, I mean basically 30 and older.

00:41:30.080 | The reason you can recover more quickly from injuries

00:41:32.800 | if you have a healthy thyroid and healthy thyroid pathways

00:41:36.280 | is because you can consume energy,

00:41:38.700 | that energy is diverted toward bone repair

00:41:41.780 | and muscle repair and cartilage repair.

00:41:43.860 | And so the way it does this again is by increasing ATP,

00:41:47.760 | but the whole idea here is that iodine, selenium,

00:41:52.760 | L-tyrosine allow thyroid to be at healthy levels

00:41:55.380 | so that thyroid then can take glucose in the blood

00:41:58.720 | and divert it to tissues for it to be used,

00:42:01.280 | in particular your brain.

00:42:02.540 | And that's why these things that we're talking about

00:42:05.360 | supplementing or getting from food

00:42:07.700 | can actually improve or support brain function.

00:42:10.900 | People are always asking me,

00:42:11.920 | what is the food that I should eat for my brain?

00:42:14.820 | Like, are blueberries good for your brain?

00:42:16.440 | Or they do ask me, are walnuts good for your brain?

00:42:18.820 | 'Cause it looks like a brain.

00:42:20.180 | We talked about that earlier.

00:42:21.540 | The fact of the matter is that what you need are nutrients

00:42:25.000 | that support hormones and biological pathways

00:42:27.820 | that support the brain.

00:42:28.720 | That's the way to think about it.

00:42:29.920 | And I realized when people ask,

00:42:31.180 | what should I eat to support my brain?

00:42:32.640 | That's basically what they're asking in short form.

00:42:35.720 | So keeping your thyroid hormone healthy,

00:42:38.980 | at healthy levels that is,

00:42:40.680 | is going to be terrific for your brain

00:42:42.500 | because 75% of your metabolism is from your brain.

00:42:45.660 | The ability of your brain to use glucose or ketones

00:42:48.220 | for that matter is going to be aided

00:42:50.020 | by having healthy thyroid.

00:42:52.180 | So do the things, take the things,

00:42:54.480 | eat the things that are going to allow you

00:42:56.340 | to have healthy levels of thyroid hormone.

00:42:58.980 | I'm sure a number of you are out there wondering,

00:43:00.800 | do I have healthy levels of thyroid hormone?

00:43:03.280 | Those can be measured from the blood.

00:43:04.840 | There's some telltale signs of having really high thyroid

00:43:08.520 | or really low thyroid.

00:43:10.160 | And I could start listing those off.

00:43:11.560 | They're easy to find online as well.

00:43:13.560 | Things like bulging eyes, inability to maintain weight,

00:43:17.320 | shaky, anxiety, that's kind of hyperthyroidal,

00:43:20.620 | thinning of hair, this kind of thing.

00:43:22.520 | I don't want to get into diagnosing hypothyroidism

00:43:26.720 | and hyperthyroidism.

00:43:27.840 | It's just impossible 'cause you're there and I'm here

00:43:30.300 | and we're kind of shouting back and forth

00:43:31.540 | through a tunnel of video and comments.

00:43:34.400 | If you're concerned about having excessively high

00:43:37.120 | or excessively low levels of thyroid hormone,

00:43:39.600 | absolutely look up what the symptoms are,

00:43:41.960 | talk to your physician.

00:43:43.880 | And there are a number of good treatments.

00:43:45.560 | I didn't talk about prescription drugs

00:43:47.360 | that can improve symptoms related to hypo or hyperthyroid.

00:43:51.720 | Of course, they have synthesized thyroid.

00:43:55.200 | So if you don't make enough thyroid, you can take thyroid.

00:43:57.720 | It's by prescription.

00:43:59.160 | If you have too much thyroid,

00:44:01.180 | sometimes they'll take out the thyroid gland

00:44:03.640 | or they can administer drugs that will

00:44:06.240 | either block receptors or will interfere

00:44:09.240 | with some of the pathways from the brain to the pituitary

00:44:12.120 | or from the pituitary to the thyroid

00:44:13.960 | in order to adjust thyroid hormone that way.

00:44:16.720 | So there are the big guns in terms of the treatments

00:44:21.120 | for different thyroid disorders,

00:44:23.080 | but we're not talking about thyroid disorders.

00:44:25.000 | We're talking about how to get and maintain thyroid levels

00:44:28.340 | in healthy ranges and some straightforward ways to do that

00:44:31.300 | through diet and supplementation.

00:44:33.720 | There's also a lot of evidence that for people

00:44:35.720 | who menstruate, levels of thyroid hormone

00:44:37.600 | can fluctuate dramatically across the menstrual cycle.

00:44:40.540 | So that's really going to be a process of experimentation.

00:44:43.820 | I don't know that you could, in theory,

00:44:47.460 | take blood at different phases of your cycle

00:44:50.280 | and figure out whether or not your thyroid hormone

00:44:52.080 | was excessively high or low

00:44:53.240 | at different phases of the cycle.

00:44:54.680 | That's going to be pretty tough to do.

00:44:56.520 | If you have an endocrinologist

00:44:57.920 | that's willing to do that with you, terrific.

00:45:00.360 | I think most people are going to have to figure out

00:45:02.700 | how supplementing the sorts of things

00:45:04.600 | that we talked about before or getting them from foods

00:45:07.100 | relates to different aspects of their cycle.

00:45:09.320 | In general, the first half of the cycle before ovulation,

00:45:12.260 | people crave carbohydrates and sweets more related to the,

00:45:15.620 | and that makes total sense

00:45:17.440 | based on the biology of the menstrual cycle.

00:45:20.340 | Thyroid hormone is going to go up as you, as anyone,

00:45:24.840 | male or female, menstruating or not,

00:45:26.820 | increases more starchy carbohydrates.

00:45:29.520 | This is interesting because ketogenic diets

00:45:32.320 | have been shown to slightly lower thyroid levels,

00:45:34.620 | and that makes sense because in ketogenic diets,

00:45:37.940 | blood glucose levels are very low

00:45:40.160 | and thyroid hormone is secreted in large part

00:45:43.900 | in proportion to how much glucose is in the bloodstream

00:45:48.040 | and how much that glucose, excuse me,

00:45:50.320 | needs to be regulated.

00:45:51.760 | So I'm not trying to demonize the ketogenic diet.

00:45:54.020 | I think it definitely has its place.

00:45:56.380 | There are 22 studies now

00:45:58.640 | showing that it can dramatically reduce blood glucose,

00:46:01.920 | and about a third of those show

00:46:03.720 | that thyroid hormone levels are slightly reduced,

00:46:07.120 | sometimes significantly, if not more,

00:46:10.800 | in the ketogenic diet.

00:46:12.520 | That may explain, I want to highlight may,

00:46:15.580 | explain the fact that when people go back

00:46:17.800 | to a more traditional diet,

00:46:19.280 | if they've been on a ketogenic diet for a long time,

00:46:22.680 | that oftentimes they will gain weight very quickly

00:46:25.960 | as they bring carbohydrates back into their diet.

00:46:28.600 | Some people are cycling between ketogenic

00:46:30.360 | and non-ketogenic every three, four days,

00:46:32.160 | so-called cyclic ketogenic diet.

00:46:33.520 | Some people are staying ketogenic for long periods of time.

00:46:35.780 | Some people, six days on, one day off.

00:46:37.420 | So it was a huge variation there.

00:46:39.680 | The point is that carbohydrates,

00:46:42.360 | starchy carbohydrates in particular,

00:46:43.840 | support the healthy production of T3 and T4.

00:46:47.480 | And so if you're very low carbohydrate,

00:46:50.500 | you're going to have a reduction in T3 and T4.

00:46:53.240 | And so if you're going to bring carbohydrates

00:46:55.160 | back into your diet,

00:46:56.320 | then you might want to do it more gradually.

00:46:57.760 | And for those of you that menstruate

00:46:59.400 | and are craving carbohydrates

00:47:01.520 | in the early part of the cycle,

00:47:02.700 | that is actually associated with having a healthy cycle.

00:47:05.960 | If any of you have had a healthy cycle on a ketogenic diet,

00:47:10.020 | that would be interesting.

00:47:10.860 | Maybe let me know through the comments

00:47:12.460 | or point me in the direction of some research

00:47:14.400 | if you're aware of it.

00:47:15.500 | So as you can start to see,

00:47:16.440 | there's this really beautiful interplay

00:47:18.080 | between the different hormones,

00:47:19.200 | between insulin and glucose,

00:47:21.020 | between estrogen and thyroid,

00:47:23.800 | between thyroid and blood glucose and the ketogenic diets.

00:47:28.240 | It all starts to fit together

00:47:29.760 | in ways that make a lot of sense

00:47:31.560 | once you understand just kind of the core elements

00:47:33.640 | of what the hormones are

00:47:34.720 | and the variety of tissues that they work on.

00:47:36.980 | The simple version of this is

00:47:38.380 | if you haven't had a carbohydrate for a year,

00:47:41.380 | then your T3, T4 levels are going to be pretty low.

00:47:44.860 | And I'm sure there's some ketonistas out there.

00:47:46.660 | They're going to say,

00:47:47.500 | "Wait, no, thyroid hormone levels go up with keto."

00:47:50.040 | That might be true for other reasons,

00:47:52.640 | indirect reasons related to hormone pathways

00:47:55.600 | that are cascade from being in ketosis

00:47:58.240 | for long periods of time, great.

00:48:00.000 | But for most people that don't consume any carbohydrate,

00:48:02.660 | T3, T4 are going to go down.

00:48:04.240 | And when they start to consume foods

00:48:06.480 | that require thyroid metabolism

00:48:08.920 | in order to work with, to metabolize,

00:48:11.680 | then weight gain can sometimes happen more quickly.

00:48:14.820 | So it's just something to consider

00:48:16.520 | and it's something to work with carefully

00:48:19.840 | if you're going to be cyclic ketogenic, long-term ketogenic.

00:48:23.280 | And if you're not ketogenic

00:48:24.480 | and you're consuming carbohydrates

00:48:27.000 | and the three things that we talked about earlier,

00:48:29.460 | selenium, tyrosine, and iodine,

00:48:31.540 | chances are, unless there's an underlying condition there,

00:48:35.180 | that your levels of thyroid

00:48:36.340 | are going to be in healthy range.

00:48:38.180 | Next, we're going to talk about growth hormone.

00:48:41.100 | Growth hormone has received a ton of attention

00:48:43.760 | in the last 20 years.

00:48:45.060 | I actually remember when it was first sequenced.

00:48:47.320 | This was a huge deal.

00:48:48.160 | There was a huge patent drama.

00:48:50.560 | I won't mention the universities or the people involved.

00:48:52.780 | There were companies and monster patents and payouts.

00:48:56.300 | And it was really interesting.

00:48:57.700 | You can look that up online if you're interested

00:48:59.820 | in some of the scientific history.

00:49:01.640 | Growth hormone is a pretty straightforward one

00:49:04.460 | for you to understand now

00:49:05.460 | because it follows the exact same logic as thyroid hormone.

00:49:09.260 | In fact, their functions are so closely overlapping

00:49:12.740 | when we first look at the face of it

00:49:15.820 | that you're probably going to think,

00:49:17.020 | why do you have these two systems?

00:49:18.660 | So just very briefly, growth hormone releasing hormone,

00:49:23.660 | so remember, releasing means it comes from the brain,

00:49:25.820 | comes from the brain and tells the pituitary

00:49:28.100 | to release growth hormone.

00:49:29.580 | And then growth hormone is released into the bloodstream

00:49:31.740 | where it goes and acts on a ton of tissues,

00:49:34.000 | muscle, ligaments, bone, fat, et cetera,

00:49:38.380 | to increase metabolism.

00:49:39.940 | It sounds just like thyroid hormone

00:49:43.420 | and they do work in parallel.

00:49:44.780 | And that's why we've lumped them together

00:49:46.020 | in the same episode.

00:49:46.860 | They increase metabolism and repair and growth of tissues.

00:49:50.400 | A conversation about growth hormone would be incomplete

00:49:54.740 | if we didn't talk about the kind of extremes.

00:49:56.620 | There are certain people who are born

00:49:58.140 | that don't make enough growth hormone

00:50:00.200 | and they end up very short in stature.

00:50:03.060 | There are certain people who make a ton of growth hormone

00:50:05.940 | and they end up very, very large.

00:50:07.860 | They tend to have very large appendages.

00:50:10.140 | They have something called acromegaly.

00:50:12.140 | It's kind of like a ridging of the forehead.

00:50:15.700 | It's actually a bone ridge.

00:50:17.700 | They are giant and it used to be called giantism.

00:50:21.380 | And most people, of course, are in a range of height

00:50:26.260 | and appendage length that doesn't imply

00:50:29.220 | that there's a growth hormone disruption there.

00:50:31.920 | Growth hormone received a lot of attention

00:50:34.680 | after it was sequenced because that meant the opportunity

00:50:37.780 | to inject growth hormone and replace growth hormone

00:50:41.220 | that was lost.

00:50:42.060 | And there was actually a lot of cases

00:50:43.860 | of people taking their kids

00:50:46.380 | and trying to get them to be taller for whatever reason

00:50:49.700 | by injecting growth hormone.

00:50:51.740 | Today, we're going to talk about the things

00:50:53.360 | that anyone can do to increase growth hormone.

00:50:56.060 | And there are reasons why certain people

00:50:57.820 | would want to do that.

00:50:58.660 | People who overproduce growth hormone

00:51:00.100 | certainly would not want to do that.

00:51:01.360 | People who underproduce it would probably want to do that.

00:51:05.340 | People that make normal quote unquote levels

00:51:09.000 | of growth hormone might want to do that as they age

00:51:12.400 | because during puberty and development,

00:51:14.940 | the pituitary is churning out tons of growth hormone.

00:51:17.780 | It's responsible for the growth, not surprising,

00:51:20.780 | of the body and all its features,

00:51:23.540 | height just being one of those.

00:51:26.180 | And so as we age, we make less growth hormone.

00:51:29.020 | And that is one of the reasons

00:51:31.000 | why we recover more slowly from injuries.

00:51:34.180 | It's one of the reasons why we accumulate body fat.

00:51:37.540 | And it's one of the reasons why our metabolism slows.

00:51:40.220 | And so growth hormone replacement therapy

00:51:42.740 | has been tremendously popular in the last 20 years,

00:51:46.620 | which is not to say it doesn't carry its problems, it does.

00:51:49.500 | Here's one of the major problems

00:51:51.200 | with injecting growth hormone.

00:51:53.460 | Not saying people shouldn't do this

00:51:54.900 | if the doctor has approved it

00:51:56.300 | or it's in keeping with their particular life goals,

00:51:59.980 | but growth hormone, if it's in levels that are too high,

00:52:04.400 | will cause growth of all tissues.

00:52:07.500 | So not just muscle, not just reduction in body fat

00:52:11.100 | by metabolizing, by allowing fatty acids

00:52:15.540 | to be pulled out of storage and used for ATP,

00:52:18.140 | but it will also cause increase in growth of the heart

00:52:22.220 | and the lungs and the liver and the spleen.

00:52:24.620 | And so this is the concern with abuse of growth hormone.

00:52:28.060 | So we're not going to be talking

00:52:28.900 | about abuse of growth hormone.

00:52:30.100 | We will, however, talk about tools that anyone can use

00:52:33.660 | to increase levels of growth hormone.

00:52:35.860 | Some of them are behavioral,

00:52:36.900 | some of them are supplement-based,

00:52:38.580 | and some of them interact with behaviors and supplements.

00:52:42.240 | And what's cool about the discussion about growth hormone

00:52:45.340 | is that the tools that exist out there

00:52:47.740 | to increase growth hormone are very actionable.

00:52:50.900 | Most people can do these without the need for any equipment

00:52:53.340 | or even any supplement,

00:52:54.380 | although there are some supplement-related themes

00:52:57.860 | for tools for growth hormone increase.

00:53:00.040 | And also the increases that one can get in growth hormone

00:53:03.620 | are substantial.

00:53:05.180 | So normally when you talk about the difference

00:53:07.440 | between taking something as an exogenous substance

00:53:10.300 | like testosterone or estrogen

00:53:12.840 | versus using supplements or behaviors to increase them,

00:53:15.840 | you're talking about tenfold differences

00:53:18.200 | from administering the prescription compound.

00:53:20.940 | In terms of growth hormone,

00:53:22.880 | there are things that can increase growth hormone

00:53:24.960 | three, four, 500% or more.

00:53:29.060 | And even though that's a short-lived increase,

00:53:32.200 | they can have very powerful effects on metabolism

00:53:34.440 | and on repair of tissues.

00:53:35.840 | So let's talk about those.

00:53:37.440 | Okay, let's go step by step

00:53:39.460 | in terms of the things that anyone,

00:53:41.640 | perhaps everyone should be doing

00:53:43.140 | in order to maintain healthy growth hormone levels

00:53:45.980 | or increase growth hormone levels.

00:53:48.180 | Unless you have overproduction of growth hormone,

00:53:51.220 | chances are these things are going to benefit you.

00:53:54.280 | However, as always, I want to emphasize,

00:53:57.960 | talk to a doctor before you do anything,

00:54:00.700 | including remove any treatments.

00:54:03.300 | So anything you would add or take away,

00:54:06.100 | that's a responsibility of you and your healthcare provider.

00:54:09.220 | Okay, I don't just say that to protect me,

00:54:10.780 | I say that to protect you.

00:54:12.920 | First of all, growth hormone is released every night

00:54:16.400 | when you go to sleep,

00:54:17.540 | and it's released in the early part of sleep

00:54:20.120 | during so-called slow wave sleep.

00:54:22.040 | So the two conditions that have to be met

00:54:25.760 | in order for growth hormone to be secreted regularly

00:54:29.160 | for tissue repair, et cetera,

00:54:31.600 | are you need to get into slow wave sleep,

00:54:34.560 | the so-called deep sleep,

00:54:36.480 | and you need blood insulin and glucose

00:54:40.120 | to be relatively low.

00:54:41.760 | So eating within two hours of sleep,

00:54:44.720 | excuse me, eating within two hours of going to sleep

00:54:47.280 | is going to suppress growth hormone release.

00:54:49.160 | That's very clear.

00:54:50.660 | However, some people are going to have problems

00:54:52.920 | falling asleep if they are too hungry.

00:54:55.440 | So you have to work with that

00:54:56.920 | and decide what you're going to eat

00:54:59.480 | and when you're going to eat that thing

00:55:01.380 | so that you're not so hungry

00:55:02.600 | that you're having trouble falling asleep.

00:55:04.800 | The episodes on sleep that were covered

00:55:06.620 | in episodes two, three, and four

00:55:08.000 | of the Huberman Lab Podcast

00:55:09.740 | has I believe more tools there than you could ever want

00:55:13.120 | or make use of in terms of how to optimize sleep.

00:55:15.420 | So you can refer to those if you like.

00:55:17.580 | So don't eat too close to sleep

00:55:19.800 | and then get into slow wave sleep.

00:55:21.400 | And as I've talked about in one of those earlier episodes,

00:55:24.300 | the first half of the night,

00:55:25.780 | slow wave sleep and deep sleep predominate.

00:55:28.340 | The second half of the night,

00:55:29.240 | it's another kind of sleep we call REM sleep.

00:55:31.860 | So what is special about this early phase of sleep?

00:55:36.020 | This is how you should be thinking

00:55:37.340 | if you listen to this podcast.

00:55:39.180 | You should be thinking, okay,

00:55:40.360 | I hear that something is important,

00:55:41.920 | it's related, it's in the pathway,

00:55:43.520 | but mechanistically when we say get into slow wave sleep,

00:55:46.660 | get into deep sleep,

00:55:48.020 | that's when growth hormone is secreted.

00:55:49.940 | The question you should be asking yourselves

00:55:51.700 | as scientists of yourselves is,

00:55:55.780 | wait, why slow wave sleep?

00:55:57.620 | What in particular about slow wave deep sleep

00:56:01.440 | allows the pituitary to release growth hormone?

00:56:04.340 | Like what is it?

00:56:06.380 | Because if you can understand that,

00:56:08.240 | if you can understand a little bit of mechanism,

00:56:10.440 | there are actually ways

00:56:11.780 | that you can increase the amount of growth hormone

00:56:15.240 | that you release both in sleep and out of sleep.

00:56:18.220 | So the answer is it's delta wave activity in the brain.

00:56:22.580 | Delta waves are these big giant waves of activity

00:56:26.280 | in the brain that correlate with slow wave sleep

00:56:29.880 | as opposed to faster waves of activity

00:56:31.500 | that is associated with rapid eye movement sleep.

00:56:34.420 | So slow wave sleep and the delta activity

00:56:37.760 | actually triggers the neurons in the brain,

00:56:40.760 | the releasing hormone, right?

00:56:42.540 | Growth hormone releasing hormone neurons

00:56:44.340 | to signal to the pituitary.

00:56:46.020 | Now, how do I know this is true?

00:56:47.280 | And what can you do with this?

00:56:48.200 | Well, we know this is true

00:56:49.100 | because researchers have taken people

00:56:51.140 | and sleep deprived them and they just asked,

00:56:54.060 | well, is it just one period of time every 24 hours

00:56:57.060 | and then the pituitary releases growth hormone?

00:56:59.220 | If that were the case,

00:57:00.460 | that would say that growth hormone is just released

00:57:02.640 | in a so-called circadian dependent way.

00:57:05.340 | Every 24 hours, there's the pulse of it,

00:57:07.540 | but no, it's always relating to slow wave deep sleep

00:57:11.260 | and delta waves.

00:57:12.380 | And this is cool because what it means is that

00:57:14.860 | even if you're not measuring your brain waves during sleep,

00:57:16.980 | which most of you probably are not,

00:57:19.440 | you might be measuring slow wave sleep or deep sleep

00:57:21.580 | using a device like a whoop or an aura.

00:57:24.020 | And even if you're not,

00:57:26.180 | what this means is that during the day,

00:57:29.460 | there's the potential to also increase

00:57:32.180 | growth hormone release if you can get the brain

00:57:34.460 | into the so-called delta waves.

00:57:36.420 | And it turns out there are things you can do

00:57:38.260 | in waking as well to increase growth hormone release.

00:57:41.260 | So we're going to talk about those next,

00:57:42.860 | but as a tool and to just really make sure

00:57:45.260 | that we put brackets around this,

00:57:47.180 | try and have blood glucose not too high.

00:57:49.340 | So if you do need to eat close to bed,

00:57:50.820 | you wouldn't want to eat anything

00:57:51.980 | that would increase blood glucose too much.

00:57:54.580 | Try and not eat too close to bedtime,

00:57:57.040 | get into deep sleep early in the night,

00:57:58.980 | get the growth hormone release

00:58:00.940 | and understand that it's the delta waves of activity,

00:58:03.940 | these sweeping big waves of activity in the neurons

00:58:06.140 | that stimulate the brain to stimulate the pituitary.

00:58:08.860 | 'Cause once you understand that,

00:58:10.540 | then you have something to anchor to in terms of thinking,

00:58:13.080 | what are the things I can do in waking

00:58:15.780 | that will allow me to release more growth hormone,

00:58:18.160 | which for most people is going to be a good thing.

00:58:20.940 | Several times before on this podcast,

00:58:23.580 | I've talked about the fact that I'm not a big fan

00:58:25.900 | of melatonin supplementation for most purposes.

00:58:30.220 | It might be helpful under conditions of jet lag.

00:58:34.200 | However, there are a lot of reasons why

00:58:36.220 | I personally don't like melatonin.

00:58:38.240 | It interacts with the reproductive hormones,

00:58:41.000 | testosterone and estrogen,

00:58:42.380 | and that whole axis in ways that are unattractive,

00:58:45.500 | at least to me, it suppresses puberty during development.

00:58:48.720 | It's present in much, much higher doses in most supplements

00:58:53.080 | than one would normally make, like 100 fold, 300 fold.

00:58:57.200 | However, today I'm going to talk about an instance

00:59:00.200 | where very low levels of melatonin supplementation

00:59:03.840 | might actually be advantageous.

00:59:06.120 | And that is aiding the transition

00:59:08.860 | to the delta wave slow wave sleep I just described,

00:59:12.040 | because that's the pattern of sleep

00:59:13.980 | and brainwave activity that triggers growth hormone release.

00:59:17.900 | So whereas most melatonin supplements are one milligram,

00:59:21.500 | three milligrams, 12 milligrams, this kind of thing,

00:59:24.880 | that is super physiological.

00:59:27.300 | There are some data showing that microgram,

00:59:30.260 | maybe 500 micrograms of melatonin, so half a milligram,

00:59:35.260 | can be beneficial in shifting the pattern

00:59:38.920 | of early night sleep

00:59:39.960 | toward more of the slow wave deep sleep delta activity

00:59:43.600 | and improving growth hormone release.

00:59:45.880 | Not a lot of studies, but the ones that I saw are quality.

00:59:49.560 | They were done in subjects that, you know,

00:59:52.180 | both sexes, sufficient numbers, et cetera.

00:59:55.620 | So this is interesting.

00:59:56.540 | So if you're interested in melatonin supplementation,

01:00:00.000 | you might think about it just at very low levels, you know,

01:00:03.820 | hundreds of micrograms as opposed to the milligram dosages.

01:00:06.960 | Most of the ones out there

01:00:08.400 | are going to be in milligram dosages.

01:00:10.260 | So that's one way that some studies have shown

01:00:14.620 | that you can increase the amount of growth hormone

01:00:17.040 | that's secreted in early phases of sleep.

01:00:19.940 | Now, the delta wave activity

01:00:21.660 | and the slow wave activity in the brain

01:00:24.280 | being very important for growth hormone release

01:00:27.340 | and growth hormone release being so important

01:00:29.400 | for metabolic functions and peeling away unwanted body fat

01:00:33.360 | and repairing tissues, et cetera, forces us to ask,

01:00:36.840 | well, what other things can we do in waking

01:00:39.360 | in order to increase growth hormone release?

01:00:41.940 | So let's start with the ones

01:00:43.040 | that have a potentially big effect,

01:00:46.480 | but are a little bit harder to access.

01:00:48.360 | And for that, I want to point toward a book,

01:00:51.160 | which is really kind of interesting.

01:00:52.680 | It's not focused on growth hormone,

01:00:54.440 | but the book is called "Altered Traits."

01:00:56.940 | This is the book.

01:00:58.440 | It's an excellent book.

01:01:00.240 | "Altered Traits" by Goleman and Davidson.

01:01:03.060 | "Science Reveals How Meditation Changes

01:01:05.180 | "Your Mind, Brain, and Body."

01:01:07.360 | Very interesting book.

01:01:09.080 | For those of you that are interested in meditation,

01:01:11.520 | and perhaps those of you who are not,

01:01:14.140 | but are considering it,

01:01:15.240 | what they talk about in this book is the fact

01:01:18.200 | that meditation has two separate lines of effects.

01:01:21.120 | One of those lines of effects

01:01:23.380 | are things that change your state.

01:01:25.200 | So you're stressed, you sit down, you meditate,

01:01:27.880 | and you relax, and you go into a particular state.

01:01:29.840 | The other are the changes that occur over time,

01:01:32.620 | and those are changes in trait.

01:01:34.600 | So personality can actually change

01:01:36.680 | with long bouts of TM meditation or repeated meditation.

01:01:41.680 | In any case, the reason we're talking

01:01:44.080 | about altered traits today is because certain types

01:01:49.080 | of meditation can get people's brains into states

01:01:53.640 | that very closely mimic slow wave sleep.

01:01:56.560 | If you hear snoring in the background, Costello is,

01:01:59.640 | it sounds like he's in slow wave sleep,

01:02:01.440 | these big oscillatory snores

01:02:04.280 | that he's in 23.6 hours per day.

01:02:07.920 | So what this means is for people

01:02:10.560 | that are interested in increasing growth hormone,

01:02:13.560 | a meditation practice that allows you

01:02:15.580 | to get into these slow wave delta-type frequency activity

01:02:20.580 | in the brain may be very beneficial

01:02:24.760 | because as I mentioned before,

01:02:25.880 | that's what's gating growth hormone release.

01:02:28.040 | It's not just a circadian phenomenon.

01:02:29.880 | It's actually controlled by these brain waves.

01:02:32.960 | I did look up binaural beats.

01:02:34.920 | I get so many questions about binaural beats,

01:02:36.940 | and it's a really attractive idea, right?

01:02:38.560 | Binaural beats, for those of you who don't know,

01:02:39.900 | you listen to one frequency of tone, do, do, do, do, do,

01:02:42.520 | in one ear and another frequency of tone in the other ear,

01:02:44.560 | do, do, do, and then the brain essentially

01:02:48.240 | takes the average of the two,

01:02:50.080 | or there's some other wiring in the brainstem

01:02:52.840 | that makes it not quite the average,

01:02:54.040 | but takes the average of the two for sake of discussion,

01:02:57.560 | and that frequency is what the brain entrains

01:03:00.280 | or maps onto.

01:03:01.900 | There are a lot of apps that are claiming

01:03:03.800 | that you can get the brain into delta waves

01:03:05.800 | using binaural beats.

01:03:06.880 | I could not find quality peer review studies

01:03:09.840 | supporting that, but I know there are a lot of fans

01:03:11.900 | out there of binaural beats.

01:03:13.200 | If you know of any literature that's independent

01:03:15.520 | of the company that makes the binaural beat technology,

01:03:18.660 | so unbiased research, please send it my way,

01:03:21.960 | but in "Altered Traits," Goleman and Davidson talk about

01:03:26.960 | the fact that people who do 20 minutes

01:03:29.320 | of sitting meditation per day

01:03:31.920 | can access these slow wave sleep-like brain states.

01:03:36.920 | Now, I've talked a lot on here about non-sleep deep rest,

01:03:40.360 | things like yoga nidra and hypnosis.

01:03:42.600 | I'm not aware that those will put people

01:03:44.560 | into slow wave sleep per se, or delta waves per se,

01:03:48.840 | so we're really talking about 20 minutes

01:03:50.400 | of more traditional type meditation.

01:03:52.240 | Okay, so we talked about very low doses of melatonin

01:03:55.700 | as a way to trigger delta waves

01:03:57.200 | and more growth hormone release in sleep.

01:03:59.600 | There's science to support that.

01:04:00.840 | We've now talked about a waking behavior of 20 minutes

01:04:05.100 | of sort of what I would call standard meditation

01:04:08.000 | of just sitting there, concentrating on one's breathing

01:04:10.000 | to try and access delta waves, binaural beats,

01:04:13.880 | no science yet, who knows?

01:04:15.540 | Maybe there's science to support it.

01:04:17.280 | If you're aware of it, let me know.

01:04:18.900 | Now let's move to the things that one can do

01:04:21.580 | that have been shown to have, let's just be honest,

01:04:25.080 | pretty enormous effects on growth hormone release in waking.

01:04:28.900 | And these are things that are very actionable.

01:04:31.880 | One of the things that can have a dramatic effect

01:04:34.240 | on levels of growth hormone release in waking,

01:04:37.080 | as well as in sleep the following night, is exercise.

01:04:42.020 | But the key is the type of exercise and the duration.

01:04:46.600 | Now there's a logic to this.

01:04:48.880 | There are hundreds, if not thousands of studies

01:04:51.280 | measuring growth hormone, both during

01:04:54.400 | or sometimes after exercise or the following night.

01:04:59.740 | And the conclusion that one takes away from all of these

01:05:03.160 | is that exercise has to be of particular duration

01:05:07.780 | and intensity in order to get growth hormone release.

01:05:10.780 | So first I'm just going to tell you what I found to be

01:05:13.480 | the maximum amount of growth hormone release

01:05:15.880 | as it relates to a particular form of exercise.

01:05:18.880 | The particular form of exercise is either weight training

01:05:22.200 | or it can be endurance training,

01:05:25.820 | but the endurance training and the weight training

01:05:28.160 | actually have to be limited to about 60 minutes,

01:05:31.420 | not much longer.

01:05:32.320 | Now this is important because it's been shown

01:05:35.880 | over and over again that if one exercise is too long

01:05:40.080 | with weights or endurance exercise,

01:05:42.000 | that cortisol levels go high enough

01:05:44.580 | that it starts to inhibit the testosterone

01:05:47.500 | and even the estrogen pathways.

01:05:49.660 | This is why I believe people who over exercise

01:05:53.440 | or exercise a lot can lose their menstrual cycles,

01:05:55.760 | they stop menstruating.

01:05:57.120 | It's why you get suppressions and testosterone

01:05:59.040 | if people train too long and too hard.

01:06:01.360 | The cutoff has always been 60 to 75 minutes

01:06:04.520 | of the hard work part.

01:06:06.360 | It's going to vary a lot from person to person,

01:06:08.800 | but in terms of growth hormone,

01:06:10.720 | the conditions that seem to lead

01:06:12.520 | to the greatest growth hormone release are one, get warm.

01:06:17.520 | This is interesting.

01:06:18.580 | We're going to talk about temperature.

01:06:19.400 | So a proper warmup seems to accelerate

01:06:22.980 | the release of growth hormone

01:06:24.840 | once the hard work phase starts.

01:06:27.240 | So 10 minutes of warmup or so was the number

01:06:30.540 | that I extracted from all these studies.

01:06:32.960 | There's a beautiful review on this by the way.

01:06:35.880 | Growth hormone response is a varying, excuse me,

01:06:40.580 | growth hormone arginine and exercise.

01:06:43.280 | We'll talk about arginine in a few minutes.

01:06:44.920 | That's by Kannalee, K-A-N-A-L-E-Y.

01:06:49.900 | It was published in Current Opinion

01:06:51.900 | in Clinical Nutrition and Metabolic Clear.

01:06:54.480 | The Current Opinion journals are generally

01:06:56.640 | of pretty high quality in terms of the reviews,

01:07:00.120 | just because they tend to be pretty recent.

01:07:01.800 | And then the references therein are also quite good.

01:07:06.140 | So what does this mean?

01:07:07.520 | This means warm up.

01:07:08.880 | And when you say warm up,

01:07:09.880 | it doesn't mean just warm up the limbs and tissues

01:07:12.560 | that you're going to use so you don't get injured,

01:07:14.100 | actually warm the body.

01:07:15.960 | So there was actually some discussion

01:07:17.540 | about whether or not in cold winter months,

01:07:19.360 | people should wear like a stocking cap,

01:07:21.860 | bringing the conditions of making the room warm.

01:07:25.200 | So getting the body warm as a warmup seems to be important

01:07:28.380 | because temperature of the body

01:07:30.360 | seems to be an important condition

01:07:32.600 | or prerequisite for certain patterns of exercise

01:07:35.600 | to maximize growth hormone release.

01:07:37.720 | So this is really interesting to me.

01:07:39.960 | I have an obsession with how body temperature,

01:07:41.920 | light exercise and food interact.

01:07:44.060 | We're going right there with the fact that if you get warm,

01:07:47.640 | you bring up the body temperature a degree or two

01:07:49.940 | or maybe three, and then start exercise.

01:07:53.800 | It does appear that high intensity exercise,

01:07:57.600 | but again, as discussed in a previous episode,

01:08:01.160 | not exercise that brings muscles to failure,

01:08:05.200 | but close to it.

01:08:06.240 | So if it's weight-bearing exercise,

01:08:08.080 | it would be getting close to that final repetitions

01:08:11.120 | where you can't complete them,

01:08:12.160 | but not pushing through those or even going to failure,

01:08:14.660 | but getting close leads to anywhere from 300 to 500%

01:08:19.400 | increases in resting growth hormone levels,

01:08:21.940 | and 300 to 500% increases in growth hormone

01:08:26.040 | the following night when you go to sleep,

01:08:28.320 | which is incredible.

01:08:30.220 | Now, I want to dissect this properly, okay?

01:08:33.200 | So one of the other conditions that seemed to be important,

01:08:37.060 | again, was to have relatively low blood glucose.

01:08:40.440 | So it's looking a lot like the conditions you need

01:08:42.480 | for sleep in order to get maximum growth hormone release

01:08:45.120 | in sleep.

01:08:45.960 | So not having blood glucose too high or too low,

01:08:49.100 | that's a discussion unto itself.

01:08:51.560 | You want to have sufficient energy to do the exercise,

01:08:54.200 | but getting warm, not having blood glucose too high

01:08:56.760 | or too low, so probably not eating too close to exercise

01:08:59.760 | or not ingesting a lot of sugars during the exercise.

01:09:04.260 | That was supported by the fact that ingestion

01:09:06.260 | of a sports drink that contains caloric sugar

01:09:09.320 | immediately flatlined the growth hormone levels.

01:09:12.200 | So really interesting relationship

01:09:14.160 | between insulin, glucose, and growth hormone.

01:09:17.040 | So then doing the training for anywhere from 60 to 75 minutes

01:09:21.360 | to maximize growth hormone release.

01:09:23.040 | And then the other interesting thing

01:09:25.880 | was that even after the exercise,

01:09:28.560 | taking body temperature back down to normal levels

01:09:31.480 | relatively quickly seemed to be associated

01:09:35.120 | with these big spikes in growth hormone.

01:09:37.120 | Otherwise, what would happen is you get these big spikes

01:09:39.040 | in growth hormone, but if the exercise went too long

01:09:41.960 | or if body temperature remained too high for too long,

01:09:44.760 | then you didn't get the second increase in growth hormone

01:09:47.500 | the following night, okay?

01:09:48.900 | So I hope I made that abundantly clear.

01:09:50.720 | Warm up well, get body temperature up,

01:09:53.100 | exercise 60 to 75 minutes.

01:09:55.560 | Don't go to absolute failure

01:09:57.060 | if your interest is in growth hormone release

01:10:00.820 | both during the exercise and later that night.

01:10:04.180 | And if you can bring body temperature

01:10:06.880 | back down to normal levels by cooling off,

01:10:08.780 | maybe cool shower or maybe ice pack or something,

01:10:11.040 | or maybe just turning off the heat in the room

01:10:13.960 | or going outside, whatever it is,

01:10:15.820 | then you increase the probability

01:10:17.380 | that you're going to increase growth hormone

01:10:19.680 | the following night as well.

01:10:21.540 | And again, these are big increases, 300 to 500%.

01:10:24.140 | It's almost like you're getting a second sleep during the day

01:10:27.360 | but if the exercise is too hard,

01:10:28.920 | if body temperature stays too high for too long,

01:10:31.600 | you disrupt the whole process

01:10:33.160 | and you don't get the effect of increased growth hormone.

01:10:35.800 | Growth hormone is really powerful, but it doesn't work alone.

01:10:39.080 | In fact, a lot of the effects of growth hormone

01:10:40.880 | are mediated by its effects on the liver.

01:10:43.660 | So growth hormone is released, goes to the liver

01:10:45.560 | and then the liver releases something called IGF-1,

01:10:47.960 | insulin growth factor one.

01:10:50.400 | Insulin growth factor one was popular

01:10:53.400 | in the neuroscience community as an area of focus

01:10:55.680 | because of its ability to trigger improvements

01:10:58.240 | in memory and learning after exercise.

01:11:01.360 | And indeed, exercise triggers both the release

01:11:03.640 | of growth hormone and IGF-1.

01:11:05.900 | IGF-1 seems responsible for a lot of the effects

01:11:08.660 | of improved memory.

01:11:10.560 | Some people report that that is due to increased number

01:11:14.100 | of neurons or neurogenesis, birth of new neurons.

01:11:16.540 | It's pretty clear that in humans,

01:11:18.180 | that's not what's happening.

01:11:19.820 | Yes, in animals, not in humans.

01:11:21.220 | IGF-1 nonetheless has positive effects

01:11:23.440 | on memory and cognition.

01:11:25.240 | And a great way to trigger IGF-1 release

01:11:27.340 | and growth hormone release is through exercise.

01:11:30.480 | Now, the interesting thing,

01:11:32.460 | and the reason I'm bringing up IGF-1 here

01:11:35.000 | is that certain patterns of exercise,

01:11:37.460 | actually duration of exercise,

01:11:39.340 | have different effects on IGF-1 and growth hormone,

01:11:42.440 | depending on whether or not the exercise

01:11:45.760 | is done by men or women.

01:11:47.560 | There's what we call a sex dependent effect.

01:11:50.500 | And the sex dependent effect is as follows.

01:11:53.800 | In this particular study and several others,

01:11:55.960 | what they did is they had people exercise,

01:11:58.440 | they measured growth hormone and IGF-1 levels

01:12:01.720 | from the blood before, during, and after exercise.

01:12:05.640 | And they could see when the greatest increases occurred.

01:12:08.340 | This was standard sorts of resistance exercise.

01:12:11.720 | So some squats, there was a sprint-like activity.

01:12:17.400 | It doesn't really matter what the specific exercises were.

01:12:21.780 | None of them were to failure.

01:12:22.880 | These were in kind of the 10 repetition or less range,

01:12:26.580 | six sets, so kind of standard weight training stuff

01:12:28.800 | that anyone might do.

01:12:31.600 | But what was interesting is that women were able to access

01:12:35.180 | the biggest peak in growth hormone and IGF-1

01:12:38.020 | early in the exercise, so in the first 30 minutes.

01:12:40.920 | So what this means is even if you just have 30 minutes,

01:12:45.140 | at least for women, there's going to be a big increase

01:12:48.860 | in growth hormone and IGF-1 in the first 30 minutes.

01:12:51.000 | For men, the biggest increase occurred later

01:12:53.920 | in the exercise, which was 60 minutes or so total.

01:12:58.920 | And so the sex dependent effects are interesting.

01:13:02.580 | They point to the fact that things like cortisol,

01:13:04.500 | testosterone, and estrogen, which of course vary

01:13:06.580 | in different levels in men and women,

01:13:08.600 | are going to impact the release of things like IGF-1

01:13:12.700 | and growth hormone.

01:13:13.540 | And yes, they did control for all sorts of things

01:13:16.260 | like diet and they controlled for weight

01:13:18.900 | and prior experience.

01:13:19.980 | It's actually a quite nice study.

01:13:21.760 | If you'd like to check it out, it's by Pierce et al,

01:13:25.340 | Growth Hormone and Insulin Glow Factor-1 Molecular Weight.

01:13:28.500 | Isoform response to resistance exercise are sex dependent

01:13:32.180 | in frontiers and endocrinology, fine journal in 2020,

01:13:35.780 | so it's quite recent.

01:13:37.100 | So what does this mean?

01:13:38.420 | This means if you're exercising

01:13:41.180 | and you want growth hormone release, warm up,

01:13:43.800 | do the type of exercise we've been discussing.

01:13:46.100 | Women in the first 30 minutes

01:13:48.980 | is when you're going to get the maximum benefit

01:13:50.660 | in terms of growth hormone and IGF-1.

01:13:52.580 | Men, you have to keep going for the entire 60 minutes,

01:13:55.860 | so don't tap out early if you're interested

01:13:58.220 | in getting the growth hormone and IGF-1 release.

01:14:00.860 | And the same conditions apply about then cooling down

01:14:04.120 | and not making the exercise last so long

01:14:06.220 | that you don't get the increase in growth hormone

01:14:08.180 | the following night.

01:14:09.820 | My experience thus far in doing this podcast

01:14:13.260 | is that people fall into one of two categories.

01:14:16.120 | There are the, just tell me what to take people,

01:14:18.900 | the people that are really eager to try supplements

01:14:21.980 | and maybe even prescription compounds.

01:14:24.180 | And then there are people

01:14:25.020 | who are a little bit more shy about supplementation.

01:14:28.460 | They are more focused on what they can do with diet

01:14:30.640 | and behaviors and things of that sort.

01:14:32.900 | I don't have a bias either way.

01:14:34.100 | I try and offer tools that are supported

01:14:36.540 | by the scientific literature.

01:14:38.240 | And I always point to safety margins.

01:14:41.320 | There are supplements that can increase growth hormone

01:14:44.360 | to a considerable degree.

01:14:46.320 | And no, these aren't growth hormone itself,

01:14:49.080 | although that of course will increase growth hormone

01:14:51.080 | to a considerable degree.

01:14:52.060 | We will talk about prescription drugs at the end,

01:14:54.160 | not just growth hormone,

01:14:55.440 | but some other things that are quite prominently

01:14:58.440 | in use right now,

01:14:59.520 | in particular in the entertainment industry.

01:15:02.760 | It's pretty interesting compounds.

01:15:06.260 | But first let's talk about supplements.

01:15:07.920 | So this has been known about for some time,

01:15:10.500 | but arginine, the amino acid arginine,

01:15:14.280 | as well as the amino acid ornithine

01:15:17.020 | can increase growth hormone levels substantially.

01:15:20.540 | Now, arginine has a number of effects.

01:15:24.620 | You can get it from food, you can get it from supplements.

01:15:27.180 | Some people take it in pill form or capsule form.

01:15:30.780 | Some people will actually take it by IV, intravenously.

01:15:36.080 | The levels and the amounts of arginine required

01:15:39.600 | to get big growth hormone release increases

01:15:42.560 | is pretty substantial.

01:15:43.680 | So some people will take arginine before bedtime.

01:15:46.880 | Some people will take it before exercise.

01:15:49.720 | The prerequisite again is low blood glucose.

01:15:53.400 | Blood glucose is high, it's going to quash the effect.

01:15:56.820 | The amounts of arginine that people take

01:15:59.720 | are anywhere from three grams

01:16:02.560 | to 10 grams or sometimes even more.

01:16:05.640 | Although this is definitely a case of more is not better.

01:16:09.580 | There is a threshold at which growth hormone release

01:16:12.800 | is actually blunted by taking

01:16:14.840 | more than nine grams of arginine.

01:16:17.840 | Now, nine grams of arginine orally is a lot of pills.

01:16:20.680 | It's at minimum nine pills

01:16:23.020 | and it can cause some GI disturbance, right?

01:16:26.640 | People can feel nauseous, some people will throw it up.

01:16:29.080 | Some people get some constipation or diarrhea, et cetera,

01:16:34.080 | or just stomach aches.

01:16:35.520 | I'm certainly not suggesting people do this.

01:16:37.720 | They're not that they take arginine,

01:16:39.480 | but that's the reason why most of the studies

01:16:42.680 | that looked at the role of arginine

01:16:44.560 | on growth hormone levels did it by IV intravenous infusion.

01:16:49.560 | So what's interesting, however,

01:16:52.600 | is that whether or not it's by mouth or by vein,

01:16:56.980 | taking arginine can dramatically increase

01:17:00.200 | growth hormone release.

01:17:01.600 | And the levels or the amount of increase

01:17:05.380 | raised was anywhere from 100 on the low end,

01:17:09.640 | but anywhere from basically from 400 to 600%

01:17:13.300 | above baseline.

01:17:14.140 | So these are huge increases in growth hormone.

01:17:17.740 | Now I've never tried arginine.

01:17:19.340 | Arginine is out there for a number of different purposes.

01:17:22.880 | One of them is to increase growth hormone.

01:17:24.920 | And some of the supplements out there

01:17:26.920 | to increase growth hormone include arginine and ornithine.

01:17:30.320 | Arginine does have the effect of dilating arterioles

01:17:35.200 | and it basically increases blood supply.

01:17:39.180 | The arginine pathway is involved in vasodilation.

01:17:42.140 | It's actually the pathway that's downstream

01:17:44.600 | of a lot of drugs that are used

01:17:46.460 | to treat things like erectile dysfunction.

01:17:49.020 | And anytime people have problems

01:17:51.860 | with peripheral blood flow of any kind,

01:17:55.020 | they focus on compounds that will either disrupt the enzymes

01:18:00.020 | or will adjust the levels of amino acids

01:18:03.980 | to get more vasodilation.

01:18:05.340 | So taking arginine for the purpose

01:18:07.500 | of increasing growth hormone will also have the effect

01:18:10.300 | of dilating blood vessels.

01:18:11.980 | And for people with blood, excuse me, with heart conditions,

01:18:14.380 | that actually can be a serious issue.

01:18:17.220 | Now here is something really important

01:18:19.300 | and interesting to note,

01:18:20.780 | which is that increasing arginine levels

01:18:24.900 | with the specific goal of increasing growth hormone release

01:18:28.420 | can actually short circuit the effects of exercise

01:18:33.420 | on growth hormone.

01:18:34.340 | Several studies that I looked at looked at the interaction

01:18:37.660 | of taking arginine and the exercise

01:18:42.120 | or just the arginine or just the exercise alone.

01:18:44.780 | And so you don't, unfortunately,

01:18:47.040 | if growth hormone increases your goal,

01:18:48.660 | you don't unfortunately get to increase growth hormone 800%

01:18:52.160 | by taking arginine and exercising.

01:18:53.860 | It always seems to be clamped

01:18:55.200 | at about 300 to 500% increases, still large increases.

01:18:59.180 | So I make that point for several reasons.

01:19:00.900 | First of all, be aware that arginine has these other effects

01:19:04.600 | on vasodilation.

01:19:05.620 | Take those seriously if you have a heart condition

01:19:08.180 | or take them seriously in any case.

01:19:10.620 | Second of all, you can supplement with arginine,

01:19:13.500 | not exercise and get these big increases in growth hormone

01:19:17.120 | by taking them before sleep.

01:19:19.140 | But if you're taking the arginine before exercise,

01:19:23.300 | you are going to short circuit or clamp the effects

01:19:26.380 | of exercise on growth hormone, okay?

01:19:29.020 | So it's something that one could use,

01:19:31.720 | but it doesn't have a synergistic effect with exercise.

01:19:35.420 | The two more or less cancel each other out, not to zero,

01:19:39.180 | but you end up with the same effect you would

01:19:41.100 | had you done one or the other.

01:19:42.840 | So hopefully that's clear.

01:19:44.280 | The other thing is if one's goal is really

01:19:46.640 | to increase arginine in the blood for whatever reason,

01:19:49.460 | arginine may not actually be the best way to do that

01:19:53.140 | because of the way it's metabolized in the gut.

01:19:56.180 | It doesn't have access or get access to the tissues

01:20:00.080 | that you're most interested in

01:20:01.620 | in terms of increasing growth hormone

01:20:03.220 | or vasodilation for that matter.

01:20:04.860 | And in that case, there's something else called L-citrulline

01:20:08.220 | which has powerful effects on vasodilation,

01:20:11.860 | powerful effects potentially on growth hormone levels

01:20:16.860 | via the arginine pathway.

01:20:19.180 | But basically L-citrulline acts as sort of a donor

01:20:23.540 | or let's say it's kind of a biological prerequisite

01:20:25.880 | for arginine and can lead to even bigger arginine increases

01:20:29.760 | than you would get if you took arginine itself.

01:20:32.180 | And so L-citrulline is out there.

01:20:34.660 | Keep in mind that anything that dilates the blood vessels

01:20:37.680 | will lower blood pressure.

01:20:39.100 | So L-citrulline, yes, will lead to increased blood flow

01:20:42.020 | for whatever purpose you want to use it for,

01:20:44.620 | whether or not that's pumps in the gym or whatever.

01:20:47.140 | It also can lead to big increases in arginine

01:20:51.060 | and growth hormone, but it will lower blood pressure.

01:20:54.200 | So be aware of that.

01:20:55.500 | But, and understand that the biology

01:20:57.660 | isn't so straightforward.

01:20:58.700 | L-citrulline may actually be the better way

01:21:00.400 | to get arginine increases than arginine itself.

01:21:03.900 | And ornithine can also increase growth hormone,

01:21:07.780 | although that's also through an indirect pathway.

01:21:10.140 | And nowadays there isn't a lot of focus on ornithine

01:21:13.440 | as a way to increase growth hormone.

01:21:15.420 | That was kind of all the rage in the '90s,

01:21:17.700 | not so much anymore.

01:21:18.740 | Nowadays, the people who are really in the know

01:21:20.560 | for this stuff tend to focus on L-citrulline.

01:21:23.400 | And if you're interested in L-citrulline or arginine,

01:21:26.560 | I highly recommend you go to our old friend,

01:21:30.320 | good friends examine.com,

01:21:32.560 | because there you can put it into the list.

01:21:35.880 | You can just put search and it's totally free.

01:21:39.000 | And it will tell you that blood pressure

01:21:41.400 | will be slightly decreased,

01:21:42.480 | power output in the gym will increase.

01:21:44.460 | There's very strong effects on blood glucose.

01:21:46.360 | Fatigue is reduced notably, big increases in nitric oxide.

01:21:51.200 | That's also related to the increase in vasodilation,

01:21:54.040 | plasma arginine, very high, excuse me, notable effects,

01:21:59.040 | very high support for studies,

01:22:01.980 | which allow people more training volume,

01:22:03.840 | aerobic exercise, arterial stiffness is brought down.

01:22:06.420 | There's a huge list of things, increase in growth hormone.

01:22:09.660 | So two studies showing this was done double blind.

01:22:13.520 | Great, you always want to see double blind,

01:22:15.000 | placebo controlled.

01:22:16.080 | This was only done in males, not in females.

01:22:18.960 | Unfortunately, just have data from males,

01:22:21.760 | but increases in growth hormone.

01:22:23.760 | It's a small, but a real significant effect.

01:22:27.400 | And again, from quality studies.

01:22:29.300 | So there's a huge number of effects there.

01:22:31.400 | And some of the other kind of more interesting ones

01:22:34.680 | about L-citrulline that you might not have thought about

01:22:39.000 | are things like muscle oxygenation,

01:22:42.060 | as we scroll down, decreases in C-reactive proteins.

01:22:47.280 | So a lot of the same things that you might expect,

01:22:50.240 | excuse me, from the same sorts of compounds we saw before.

01:22:53.020 | The takeaway here is if you want to increase growth hormone,

01:22:56.160 | think about the arginine pathway,

01:22:57.800 | but arginine itself might not be

01:23:00.160 | the best direct route to get there.

01:23:01.540 | L-citrulline might be a better option,

01:23:03.860 | but please do consider and take very seriously

01:23:07.100 | the effects on blood pressure.

01:23:08.600 | So we've been talking about big effects

01:23:11.880 | from supplementation or exercise on growth hormone,

01:23:15.380 | this extremely powerful hormone.

01:23:17.720 | And one thing to note is that the profile of growth hormone

01:23:22.320 | as we age changes.

01:23:24.200 | I mentioned that earlier,

01:23:25.500 | but it's important to understand how it changes.

01:23:28.520 | One thing that's particularly interesting to me

01:23:30.200 | as somebody who's in his 40s

01:23:31.960 | is that it's actually between ages 30 and 40

01:23:36.620 | that the amount of growth hormone that you release

01:23:39.120 | each night is reduced by two to threefold.

01:23:42.960 | That's really incredible.

01:23:44.660 | We hear so much about testosterone levels going down

01:23:47.760 | as we age or estrogen levels going down.

01:23:49.960 | But if you recall from the testosterone and estrogen episode

01:23:53.360 | talked about the fact that if you really look at the data,

01:23:55.980 | just for instance, on testosterone,

01:23:58.080 | there are men in their 90s and they are not rare,

01:24:02.160 | it turns out, that are making as much testosterone

01:24:05.480 | and DHT, dihydrotestosterone, as they were in their 20s.

01:24:09.400 | Okay, so we hear so much nowadays

01:24:11.160 | about how testosterone levels are dropping,

01:24:13.360 | sperm levels are dropping, et cetera.

01:24:15.520 | And I don't dispute that.

01:24:17.420 | I talked about that in that episode.

01:24:19.540 | But it's clear that testosterone levels vary tremendously

01:24:22.580 | from person to person.

01:24:23.960 | And just getting older does not necessarily mean

01:24:26.520 | that testosterone levels are dropping.

01:24:28.760 | Growth hormone levels, it seems,

01:24:31.400 | are dropping when people are in their 30s and 40s

01:24:33.900 | and they're dropping substantially.

01:24:35.340 | And that seems to be the case across the board.

01:24:37.580 | You're just not going to find people in their 40s, 50s,

01:24:39.960 | and 60s that are making as much growth hormone

01:24:42.540 | as they were in their teens and 20s.

01:24:44.780 | And as somebody who, I feel really good,

01:24:48.300 | but as somebody who definitely noticed

01:24:50.660 | that as I got into my 40s,

01:24:51.920 | that even if I slept the same amount,

01:24:54.160 | I wasn't feeling quite as, I would say,

01:24:58.140 | able to recover from exercise or wound healing,

01:25:02.160 | even with the same amount of sleep.

01:25:03.500 | And I was trying to optimize a great number of things.

01:25:05.880 | This business of growth hormone

01:25:07.640 | became a particular interest to me.

01:25:09.400 | And since the ways to manipulate growth hormone

01:25:11.760 | in men and in women are so straightforward,

01:25:14.040 | and since everybody goes through this age-related decline

01:25:17.020 | very dramatically, it seems to me that the things

01:25:19.980 | that we're supposed to be doing anyway, like exercising,

01:25:22.840 | like trying not to eat too close to bedtime,

01:25:24.620 | trying to optimize sleep,

01:25:25.700 | all of these are wonderful tools

01:25:27.100 | that we should be pursuing and perhaps using,

01:25:31.540 | and they can actually offset

01:25:34.220 | the two to three-fold decrease, right?

01:25:36.320 | If we're talking about a two to three-fold decrease

01:25:38.120 | for people that are in their 30s and 40s,

01:25:40.240 | and then we're talking about increases from exercise

01:25:43.280 | or from maybe from supplementation,

01:25:45.160 | but certainly from exercise of 300 to 500%,

01:25:49.000 | well, then all of a sudden we're in a position

01:25:50.960 | to actually offset the age-related decline

01:25:53.160 | in growth hormone completely just through behaviors.

01:25:55.800 | And I think that's quite interesting and quite powerful.

01:25:59.120 | Now I'd like to discuss a way that anyone can increase

01:26:01.680 | their levels of growth hormone dramatically.

01:26:04.160 | And when I say dramatically, I mean dramatically.

01:26:06.520 | I'll get to the numbers in a couple of minutes,

01:26:08.400 | but we have to remember how growth hormone

01:26:12.400 | is released in the first place.

01:26:14.480 | Remember, it all starts in the brain, in the hypothalamus.

01:26:18.000 | The hypothalamus is a brain area

01:26:19.440 | that controls things like sexual behavior,

01:26:22.320 | temperature regulation, circadian behavior,

01:26:25.580 | meaning when you want to be awake

01:26:26.800 | and when you want to be asleep, aggression, all of that.

01:26:30.460 | There are other brain areas involved too,

01:26:32.120 | but it has a rich collection of different neurons

01:26:35.180 | involved in all these very basic functions.

01:26:38.860 | Now, as we talked about the releasing hormones,

01:26:42.580 | the growth hormone releasing hormone

01:26:44.920 | comes from neurons in the hypothalamus.

01:26:47.300 | Those then communicate with the pituitary

01:26:49.820 | and the pituitary releases growth hormone.

01:26:52.940 | And then the growth hormone acts

01:26:54.180 | on all these different tissues,

01:26:55.300 | muscle, liver, cartilage, et cetera, body fat.

01:26:58.400 | Makes them use energy.

01:27:01.220 | That's why you lose body fat

01:27:02.260 | when growth hormone levels are high.

01:27:03.860 | Makes you grow muscle, strengthens bones, et cetera.

01:27:07.460 | Now, one of the things that has a profound effect

01:27:13.640 | on growth hormone levels,

01:27:15.800 | growth hormone release is temperature.

01:27:18.780 | Now, the data on this are very strong

01:27:21.020 | and the data come from both animal studies

01:27:23.220 | and human studies.

01:27:25.100 | So there are a number of studies that have explored

01:27:27.020 | how making animals cold or hot can increase growth hormone.

01:27:31.580 | And if you're guessing which direction this is going to go,

01:27:35.220 | you can probably imagine that making animals

01:27:38.140 | or people warmer is the way to go

01:27:41.100 | if you want to increase growth hormone.

01:27:43.220 | Now, anytime you're going to increase temperature

01:27:45.940 | of yourself or anyone else or an animal, it is risky.

01:27:49.660 | I want to be really clear about this.

01:27:51.180 | Not everyone should engage in the behaviors

01:27:54.140 | I'm about to describe, but,

01:27:57.220 | and I should just say the reason it's risky

01:27:59.100 | is it doesn't take much of a temperature increase

01:28:01.020 | in the brain to cook the brain, to cook neurons.

01:28:03.780 | And after that point, neurons can't come back

01:28:06.620 | and people can die from hyperthermia.

01:28:09.540 | We have a much greater range in terms of cold.

01:28:11.420 | You can also die of hypothermia, you can freeze to death,

01:28:14.940 | but you have a much greater range of getting cold

01:28:18.180 | than you do warming up the brain.

01:28:20.400 | However, there are really strong data pointing to the fact

01:28:24.780 | that sauna, AKA deliberate hyperthermia,

01:28:30.540 | not too high, however, that sauna can increase

01:28:34.020 | the release of growth hormone and other hormones.

01:28:36.900 | And what's so dramatic about this literature

01:28:39.060 | is the size of the effects that are reported.

01:28:42.660 | So first of all, let's talk about

01:28:45.140 | these temperature increases.

01:28:46.360 | And yes, I will refer to things that people can do

01:28:49.460 | even if you don't own a sauna,

01:28:52.340 | because I realize not everybody has sauna in their backyard

01:28:55.540 | or has access to a sauna.

01:28:57.020 | So first of all, recall our study about exercise

01:29:01.500 | where warming up a few degrees before the exercise

01:29:04.940 | led to bigger and quicker increases in growth hormone

01:29:08.580 | during the exercise bout itself.

01:29:11.100 | So that already pointed in the direction

01:29:12.640 | that temperature was important.

01:29:14.440 | Now, the degrees, no pun intended,

01:29:17.700 | that we're talking about increasing body temperature

01:29:21.620 | is by entering saunas that are somewhere

01:29:25.140 | between 176 degrees Fahrenheit,

01:29:28.140 | so that's 80 degrees Celsius,

01:29:30.220 | and all the way up to like 210, 215 degrees Fahrenheit.

01:29:36.540 | I personally know people that go even higher than that,

01:29:39.480 | but they've trained themselves to deal with very high heat.

01:29:42.260 | So again, high heat is dangerous.

01:29:43.740 | You must clear this with your doctor.

01:29:45.600 | Now, what happens in high heat?

01:29:47.460 | Couple of things happen in high heat.

01:29:48.740 | First of all, you start getting bigger stroke volume

01:29:51.940 | of the heart, kind of like an exercise.

01:29:53.500 | Once you get well-trained in endurance activity,

01:29:55.700 | your stroke volume, the amount of blood

01:29:57.180 | that your heart can pump each time gets larger.

01:29:59.640 | You dilate the blood vessels, right?

01:30:02.860 | There are a lot of things that happen also.

01:30:04.000 | You're sweating, your body's trying to unload heat.

01:30:06.660 | Dilation of blood vessels, arginine increases in heat.

01:30:11.420 | We're starting to see and hear a common theme,

01:30:14.620 | but it appears that getting into,

01:30:17.160 | I'm not saying getting the body up to 212 degrees Fahrenheit,

01:30:19.900 | I want to be very clear,

01:30:21.140 | not talking about getting the body up to 100 degrees,

01:30:23.460 | Celsius, that would be terrible.

01:30:25.460 | You would die.

01:30:26.420 | But entering environments where it's very hot

01:30:30.160 | for short periods of time,

01:30:31.380 | anywhere from 20 minutes to 30 minutes,

01:30:34.180 | where the temperature is 80 degrees Celsius

01:30:38.980 | to 100 degrees Celsius, or 175 degrees Fahrenheit,

01:30:42.540 | more or less, to about 210 degrees Fahrenheit,

01:30:45.220 | more or less, has been shown

01:30:47.380 | to increase growth hormone release 16 fold.

01:30:51.740 | That's right, 16 fold.

01:30:53.160 | That's 1,600%.

01:30:55.780 | Now, there are also effects on other hormones,

01:30:58.040 | prolactin, cortisol, et cetera.

01:31:00.520 | So the pattern that was described in this study,

01:31:04.000 | and there've been many studies now,

01:31:05.700 | endocrine effects of rupita sauna

01:31:08.840 | were done in 17 humans.

01:31:13.280 | This was from doing this repeatedly.

01:31:16.500 | So it wasn't the first time they did this.

01:31:17.860 | They actually had to do this three days in a row.

01:31:19.900 | And the pattern was to get into the sauna for 20 minutes,

01:31:23.380 | followed by a 30 minute cooling period.

01:31:25.420 | Remember, you don't want to spend long periods of time

01:31:27.200 | at high heat.

01:31:28.040 | You can cook your brain and other tissues.

01:31:30.800 | Be very careful as you approach this if you decide to.

01:31:33.320 | But 30 minutes, excuse me, 20 minutes sauna,

01:31:36.540 | followed by 30 minutes of cooling,

01:31:38.120 | followed by 20 minutes sauna, again,

01:31:40.620 | led to a five-fold increase in growth hormone.

01:31:42.680 | And then by doing that day after day after day,

01:31:47.160 | on the third day, you would see these huge increases

01:31:50.120 | of like 16-fold, up to 16-fold.

01:31:52.640 | And there are now many studies like this.

01:31:54.440 | This was described a few years ago.

01:31:57.460 | But since then, there have been a number of other studies

01:32:02.560 | that have pointed in the direction

01:32:04.020 | of deliberate hyperthermia,

01:32:07.880 | but not too hot that you kill yourself

01:32:09.960 | in order to increase growth hormone.

01:32:11.920 | And I know I keep highlighting the dangers there,

01:32:13.740 | but again, anytime you're going to mess with heat,

01:32:16.680 | you have to be cautious.

01:32:18.040 | You have to be careful.

01:32:19.000 | So standard sauna can be useful.

01:32:21.920 | If you don't have access to a sauna,

01:32:23.520 | one way that people do this,

01:32:25.280 | we have to look to our friends, the wrestlers, right?

01:32:27.640 | They wear plastics, which are basically body suits

01:32:31.240 | that are fairly inexpensive that you can buy

01:32:33.680 | on any online purchase platform, I should say.

01:32:38.680 | Some people in the old days

01:32:41.400 | before they had these plastics things so readily available,

01:32:46.720 | I actually knew people that wrapped themselves

01:32:48.660 | in garbage bags and then throw on sweats and a hoodie

01:32:50.640 | and then go out for a jog.

01:32:52.160 | Again, you have to be really careful,

01:32:53.520 | especially on a hot day, overheating can equate to death,

01:32:56.680 | but that's another way to heat up.

01:32:58.940 | You don't actually need a sauna.

01:33:00.600 | I've known people who will do this in hotel rooms

01:33:02.720 | while they're traveling.

01:33:03.960 | They'll turn on the heat, make a hot bath.

01:33:06.600 | They won't actually get in the bath,

01:33:08.400 | but they'll fill the room with steam and heat

01:33:10.320 | and they'll put on a hoodie and some sweat pants

01:33:14.000 | and they'll sit there with wool socks on

01:33:15.900 | and they'll get warm for 20 minutes.

01:33:17.580 | Then they'll take a cool shower and then they'll do it again.

01:33:20.780 | I guess when the hotel's paying the water bill,

01:33:22.700 | you don't worry about it too much.

01:33:24.080 | Some people of course own saunas.

01:33:25.520 | There are a lot of ways to do that.

01:33:26.360 | I have friends who were in the military

01:33:27.740 | who made saunas out of cars while they were overseas,

01:33:30.640 | all sorts of things.

01:33:31.680 | You do have to be careful.

01:33:32.900 | I know I've said it many, many times.

01:33:34.200 | I just don't want anyone to hurt themselves,

01:33:35.720 | but these increases in growth hormone are tremendous.

01:33:38.060 | And what they probably stem from

01:33:40.240 | are increased activity of neurons within the hypothalamus

01:33:43.880 | that stimulate growth hormone release from the pituitary.

01:33:46.820 | And that's probably because

01:33:48.960 | the growth hormone releasing hormone neurons

01:33:51.640 | in the hypothalamus sit very closely

01:33:54.440 | and may even be intermixed with some of the neurons

01:33:57.180 | in the hypothalamus that regulate heat and body temperature.

01:34:00.760 | Remember metabolism is in part a heat.

01:34:03.480 | It's like a furnace of how much energy you're consuming

01:34:06.120 | and using for building or for energy usage purposes.

01:34:11.080 | So sauna can be very, very interesting

01:34:13.620 | and again, it's 20 minutes, 30 minute cooling,

01:34:16.120 | 20 minutes again, proceed with extreme caution,

01:34:20.260 | but nonetheless, these are pretty extreme effects

01:34:23.200 | in terms of their abilities

01:34:25.060 | to increase growth hormone levels.

01:34:27.360 | Along the lines of temperature and hormones,

01:34:29.460 | I just want to mention a very recent study just came out,

01:34:32.720 | March, April, 2021,

01:34:35.360 | endocrine effects of repeated hot thermal stress

01:34:38.000 | and cold water immersion in young adult men.

01:34:40.480 | Unfortunately, it was just in men.

01:34:41.500 | They didn't look at women,

01:34:42.640 | but nonetheless, I think the data are relevant

01:34:44.620 | to everybody as a general theme.

01:34:46.600 | This is Podstrowski et al.

01:34:48.840 | I will put a link to the study in the caption.

01:34:52.500 | And they looked at testosterone, prolactin, cortisol,

01:34:56.040 | et cetera, and what they found was that

01:34:59.420 | the sauna does indeed lead to a significant decrease

01:35:03.240 | in cortisol, a stress hormone,

01:35:05.040 | a hormone that you want to be released early in the day

01:35:07.620 | when you wake up,

01:35:08.740 | but sauna definitely led to a significant decrease

01:35:12.520 | in cortisol, but did not change testosterone,

01:35:15.360 | DHEA, or prolactin levels.

01:35:17.520 | So that's interesting.

01:35:19.080 | And it turns out that the cold

01:35:21.360 | did affect some of these hormones,

01:35:24.640 | but the results there were a little bit more mixed.

01:35:27.600 | So the takeaway here is that heat

01:35:29.960 | seems to have positive effects on growth hormone,

01:35:32.560 | big effects.

01:35:33.400 | It seems to have positive effects

01:35:35.040 | on reducing cortisol levels,

01:35:37.620 | and it does not seem to have effects

01:35:39.640 | on things like testosterone, DHEA, or prolactin directly.

01:35:42.800 | You can imagine that a shift in any hormone

01:35:44.640 | is going to alter the levels of other hormones

01:35:47.200 | down the line, sort of indirect effects,

01:35:49.400 | but in terms of direct effects,

01:35:51.320 | just during or immediately after the sauna bath,

01:35:54.840 | there were no effects.

01:35:57.000 | So we've talked about diet, supplementation,

01:36:00.540 | behavioral tools,

01:36:02.560 | and of course we talked about

01:36:04.160 | the underlying biology and logic.

01:36:06.800 | And hopefully you heard the safety precautions

01:36:10.080 | for all of those.

01:36:11.820 | Now I'd like to just briefly talk about

01:36:14.880 | the prescription side of all this.

01:36:17.360 | There are, as we know, many people taking growth hormone

01:36:21.560 | because it's been prescribed to them by a doctor.

01:36:23.420 | And presumably there are people taking growth hormone,

01:36:25.580 | even though it has not been prescribed by a doctor,

01:36:27.860 | which is none of my business.

01:36:30.040 | But the point here is that

01:36:33.040 | most all of the hormones that we make

01:36:35.560 | have been synthesized.

01:36:37.260 | So there are versions of them in little bottles

01:36:40.080 | or little ampules that people can inject.

01:36:42.780 | Here are a couple of important things to consider

01:36:44.760 | if you're going to go that route.

01:36:46.840 | First of all, talk to a physician, right?

01:36:49.280 | They actually are only legally available through a physician.

01:36:52.280 | Second of all, anytime you're injecting something,

01:36:55.700 | you're going to shut down your own production.

01:36:57.540 | That's the way that the hormone system works.

01:36:59.400 | If you take thyroid hormone,

01:37:00.640 | you won't make thyroid hormone,

01:37:02.800 | at least in the long run.

01:37:04.060 | If you take testosterone,

01:37:06.460 | you will shut down your own production of testosterone.

01:37:09.540 | If you take estrogen, the system's a little more resilient,

01:37:12.900 | but eventually you will shut down

01:37:14.140 | your production of estrogen.

01:37:15.680 | And the same is true for growth hormone.

01:37:18.020 | So a decision to go that route of taking something

01:37:22.420 | is often not always a decision to do it forever.

01:37:25.140 | However, if you're willing to sustain a period

01:37:27.660 | of being without a given hormone,

01:37:29.980 | some people can do things and then stop taking them.

01:37:33.460 | And then wait out the period in which they're not making

01:37:37.360 | testosterone, estrogen, or growth hormone,

01:37:39.020 | and then it will come back.

01:37:40.180 | Sometimes, and sometimes it won't.

01:37:41.920 | There's a kind of new area that's developing now

01:37:46.060 | that I think deserves our attention,

01:37:48.160 | not because I'm encouraging it, but because it is happening.

01:37:51.340 | And in keeping with the science

01:37:54.260 | and in keeping with trying to keep things modern,

01:37:57.980 | it's worth us discussing, and those are peptides.

01:38:00.420 | So these days you hear a lot about peptides.

01:38:02.980 | I'd like to clarify a little bit about what peptides are.

01:38:06.000 | Peptides is a really huge category of biological compounds.

01:38:10.820 | Peptides are just strings of amino acids, right?

01:38:13.940 | So we've talked about L-tyrosine, arginine, ornithine,

01:38:16.380 | those are amino acids, those are individual amino acids.

01:38:18.740 | And those are put together into little small peptides,

01:38:22.960 | or they're what are called polypeptides,

01:38:25.220 | which are just longer peptides.

01:38:27.020 | Turns out that for any substance like growth hormone

01:38:31.320 | or growth hormone-releasing hormone,

01:38:32.920 | it's made up of different amino acids

01:38:34.500 | in different sequences,

01:38:35.540 | just like your genes are made up of A's and G's

01:38:38.660 | and C's and T's, nucleotides in different sequences.

01:38:41.040 | It's like a recipe.

01:38:42.300 | Peptides tend to be short sequences of amino acids

01:38:48.080 | that resemble a hormone enough

01:38:50.760 | or resemble some other peptide enough

01:38:53.440 | that it can lead to the similar or same effects

01:38:55.960 | when you inject them.

01:38:57.100 | So for example, we make growth hormone-releasing hormone

01:39:01.300 | from our brain, which stimulates growth hormone

01:39:03.220 | from the pituitary.

01:39:04.060 | You're probably getting tired of me saying that by now.

01:39:07.060 | But people now will take things like sermorelin,

01:39:11.620 | S-E-R-M-O-R-E-L-I-N, sermorelin,

01:39:16.620 | which is not the entire peptide sequence

01:39:19.540 | of growth hormone-releasing hormone,

01:39:21.460 | but it's a subset of those.

01:39:23.060 | And when people inject it before they go to sleep at night,

01:39:25.480 | it's typically how it's done on an empty stomach,

01:39:27.600 | then that stimulates the release of growth hormone

01:39:30.160 | from the pituitary.

01:39:31.280 | So this is not taking growth hormone.

01:39:33.540 | This is taking the stimulating hormone

01:39:36.040 | or what's often called a secretagogue or a mimic, all right?

01:39:40.160 | It causes a secretion of the hormone that one wants.

01:39:44.020 | People will do this for thyroid hormone too.

01:39:45.720 | Some people are doing this by prescription

01:39:48.080 | with a real medical need.

01:39:49.240 | Other people are doing it for just longevity reasons,

01:39:52.120 | which kind of falls into that gray zone

01:39:54.060 | of they wouldn't die without it,

01:39:55.760 | but they want to enhance their life.

01:39:57.460 | And so they're doing that

01:39:58.600 | because they believe it's the right thing for them.

01:40:00.360 | Prescription, sermorelin is prescription.

01:40:03.060 | Do they work?

01:40:03.960 | Yes.

01:40:05.480 | Do they shut down your natural production

01:40:08.000 | of growth hormone-releasing hormone?

01:40:10.720 | Well, the answer is yes,

01:40:13.300 | but some of these peptides actually have the effect

01:40:16.360 | of changing gene expression.

01:40:18.360 | Remember way back to the beginning

01:40:19.640 | when I was talking about hormones,

01:40:21.000 | they can actually change gene expression

01:40:22.720 | and they can actually set pathways in motion

01:40:25.600 | for continued production of a hormone

01:40:27.520 | even if you stop taking the compound.

01:40:29.880 | Now that can be good or that can be bad

01:40:31.720 | because as you recall, growth hormone in big,

01:40:34.780 | big increases in growth hormone that are short-lived

01:40:37.000 | like sauna or I should say exercise or arginine or sauna,

01:40:41.860 | it seems like has these huge effects,

01:40:43.720 | or early nights, first phase of sleep early in the night,

01:40:49.120 | these sorts of things.

01:40:50.880 | Those are transient,

01:40:52.700 | but when one is injecting over and over a constant level,

01:40:56.280 | you can put into action gene expression programs

01:40:59.280 | that can be long-lived.

01:41:00.400 | And let's say you have a particular tumor in the body,

01:41:03.400 | tumors will grow when they see growth hormone

01:41:05.540 | even if that tumor is unhealthy for you, right?

01:41:08.320 | You've got growth of tissues all over the body.

01:41:10.080 | So again, I'm not saying whether or not

01:41:11.400 | people should do these things or not doing them.

01:41:13.080 | One thing I do know is that they are in very prominent use

01:41:16.680 | in the movie industry,

01:41:17.780 | people who want to peel off body fat quickly,

01:41:19.660 | they do increase recovery time,

01:41:21.760 | they increase healing rates,

01:41:22.920 | people are also injecting things like gastric peptides,

01:41:26.160 | they're actually stomach peptides

01:41:28.200 | that we talked about in the previous episode,

01:41:30.040 | things related to the ghrelin pathway,

01:41:32.700 | and other things from the liver

01:41:34.420 | that can improve the rate of tissue and wound healing.

01:41:37.580 | You can bet that in the upcoming Olympics,

01:41:39.920 | a lot of people are using peptides and compounds,

01:41:42.440 | and I'm not pointing fingers at anyone in particular,

01:41:44.800 | it's just this is separate from hormone augmentation

01:41:47.280 | of like injecting GH or injecting testosterone,

01:41:50.000 | people are now working further up the pathways.

01:41:52.660 | Other names of some of the peptides

01:41:54.060 | are things like ipramoralin, tesamoralin,

01:41:58.940 | some of these have clinical uses,

01:42:00.820 | others have just been made as compounds

01:42:03.580 | for people in the kind of longevity field

01:42:06.780 | or the self-augmentation field, if you will.

01:42:09.620 | So again, not promoting their use,

01:42:11.260 | but they're definitely out there,

01:42:12.220 | and so now if you hear about them

01:42:14.140 | or someone's talking to you about them,

01:42:15.600 | now hopefully you have a better understanding

01:42:17.180 | about their underlying biology

01:42:18.580 | and you can think rationally about whether or not

01:42:20.740 | they are the right decision for you.

01:42:23.780 | Okay, once again, covered an enormous amount of material,

01:42:28.060 | hopefully now you understand thyroid hormone

01:42:30.340 | and what it does and a little bit about its mechanism

01:42:32.740 | or maybe a lot and growth hormone and what it does

01:42:35.300 | and how both of them take care of our metabolism,

01:42:38.940 | they dictate how many nutrients we can eat and make use of,

01:42:42.460 | they can pull from body fat stores, repair muscle,

01:42:45.500 | repair cartilage, they really are incredible compounds

01:42:48.500 | and they're actionable, they're things that we can do

01:42:50.980 | like getting that early phase of sleep,

01:42:53.460 | perhaps supplementing with arginine, maybe not,

01:42:56.620 | hopefully getting adequate exercise, warming up properly,

01:43:00.140 | not making the exercise too long or too intense will help,

01:43:03.060 | maybe sauna or things like it,

01:43:05.580 | deliberate safe hyperthermia with the emphasis on safe

01:43:09.540 | might be things that are of use.

01:43:11.620 | Regardless, even if you're not interested in the thyroid

01:43:13.940 | or the growth hormone pathways,

01:43:16.020 | this brings to a close our month on hormones

01:43:18.240 | and so now hopefully you understand

01:43:20.120 | not just thyroid and growth hormone,

01:43:21.620 | but the logic that underlies thyroid hormone,

01:43:24.340 | growth hormone, estrogen, testosterone,

01:43:26.960 | why we eat, why we stop eating, cholecystokinin, ghrelin.

01:43:31.160 | If these names don't mean anything to you,

01:43:33.020 | then perhaps go back and listen to those episodes,

01:43:35.100 | but regardless, I hope that you come away from this

01:43:37.760 | with a deeper understanding about these hormones

01:43:40.500 | which are so powerful in controlling

01:43:42.800 | the way our brain functions

01:43:44.220 | and the interplay between the brain and hormones

01:43:46.640 | because it is really a bi-directional conversation,

01:43:50.060 | the brain is telling the body what hormones to make,

01:43:52.180 | the hormones are influencing all the tissues of the body,

01:43:54.420 | but also telling the brain whether or not to eat more

01:43:56.780 | or grow more or think more, et cetera.

01:43:59.920 | So I really appreciate your time and attention.

01:44:02.780 | If you like this podcast and you're finding it useful,

01:44:06.660 | please recommend it to other people.

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01:45:01.300 | at any level that you like.

01:45:03.580 | And I mentioned supplements this episode.

01:45:06.300 | I often mention supplements.

01:45:07.820 | They are certainly not necessary,

01:45:09.420 | but for those of you interested in supplements,

01:45:11.300 | we've partnered with Thorne, T-H-O-R-N-E,

01:45:14.620 | because Thorne has the highest levels of stringency

01:45:17.180 | in terms of the quality of the ingredients

01:45:19.140 | and the amount of the ingredients

01:45:21.100 | in each capsule, tablet, powder, et cetera.

01:45:24.620 | If you want to see the supplements that I take,

01:45:26.920 | as well as get a discount on any of those

01:45:28.860 | or any of the supplements that Thorne makes,

01:45:31.180 | it's thorne, T-H-O-R-N-E, .com/u/huberman,

01:45:36.180 | and you can get 20% off any of the supplements they make.

01:45:40.240 | I should mention Thorne works with the Mayo Clinic.

01:45:43.140 | They partnered with them.

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01:45:45.900 | So really the highest levels of stringency,

01:45:47.980 | we're quite happy to be working with them.

01:45:50.220 | And last but not least,

01:45:52.100 | I thank you for your time and attention

01:45:53.820 | and above all, for your interest in science.

01:45:56.120 | [upbeat music]

01:45:58.700 | (upbeat music)

How to Control Your Metabolism by Thyroid & Growth Hormone

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