How Our Hormones Control Our Hunger, Eating & Satiety

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

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

00:00:04.900 | for everyday life.

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

00:00:10.640 | and I'm a professor of neurobiology and ophthalmology

00:00:13.720 | at Stanford School of Medicine.

00:00:15.760 | This podcast is separate from my teaching

00:00:17.520 | and research roles at Stanford.

00:00:19.360 | It is, however, part of my desire and effort

00:00:21.400 | to bring zero cost to consumer information about science

00:00:24.280 | and science-related tools to the general public.

00:00:27.360 | In keeping with that theme,

00:00:28.540 | I'd like to thank the sponsors of today's podcast.

00:00:31.480 | Our first sponsor is Inside Tracker.

00:00:33.760 | Inside Tracker is a personalized nutrition platform

00:00:37.180 | that analyzes data from your blood and DNA

00:00:39.480 | to help you better understand your body

00:00:41.260 | and help you reach your health goals.

00:00:43.680 | I've long been a fan of getting blood work done.

00:00:46.060 | And the simple reason for that

00:00:47.760 | is that most of the things that you want to know

00:00:49.980 | about your health, such as hormones, metabolic factors,

00:00:53.680 | blood sugar levels, et cetera,

00:00:55.480 | can only be analyzed from blood.

00:00:57.920 | And nowadays, there are also excellent DNA tests

00:01:00.340 | that can also give you valuable information

00:01:02.540 | about what's going on at the cellular, molecular,

00:01:05.180 | even the neural circuit level within your brain and body.

00:01:08.600 | Inside Tracker makes getting blood and DNA tests easy.

00:01:11.940 | You can go to a testing site where they draw your blood,

00:01:14.860 | they take your DNA sample,

00:01:16.080 | or they can come to your home if you prefer that.

00:01:18.640 | As well, they have a really amazing dashboard.

00:01:20.920 | The dashboard lets you understand

00:01:23.380 | what your levels of various hormones

00:01:25.420 | and metabolic factors, et cetera, mean,

00:01:27.320 | and what you should do about them.

00:01:29.000 | And I think that that's one of the main things

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00:01:34.560 | Most tests, you get the results back,

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00:01:47.800 | If you'd like to try Inside Tracker,

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00:02:04.760 | Today's episode is also brought to us by Athletic Greens.

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00:05:42.380 | This month, we're talking all about hormones.

00:05:45.180 | Hormones are incredible, and they control so many processes

00:05:48.020 | in the brain and body.

00:05:49.640 | Last episode, we talked about the role of estrogen

00:05:52.000 | and testosterone.

00:05:53.380 | Today, we're going to talk about how hormones

00:05:55.260 | impact feeding and hunger, as well as satiety,

00:05:59.080 | the feeling that you don't want to eat

00:06:00.580 | or that you've eaten enough.

00:06:02.740 | Now, it's important to understand

00:06:04.040 | that hormones don't work alone in this context.

00:06:06.700 | Today, I'm going to describe some hormones

00:06:08.520 | that have powerful effects on whether or not

00:06:10.780 | you want to eat more or less or stop eating altogether,

00:06:14.780 | but they don't do that on their own.

00:06:16.820 | They do that in cooperation with the nervous system.

00:06:19.800 | So today, I would say as much or perhaps even more

00:06:23.060 | than any other episodes, we're going to hear

00:06:25.660 | a lot of biology, but there are multiple,

00:06:27.900 | what I'm going to call entry points for tools

00:06:30.500 | that you can apply in order to regulate

00:06:32.700 | your levels of hunger, your meal timing,

00:06:35.120 | your levels of satiety of not wanting to eat more,

00:06:38.400 | and many of this is actionable with behaviors,

00:06:41.360 | but of course, we're also going to talk about supplements,

00:06:43.380 | and we're actually going to talk about

00:06:44.720 | a little bit of brain machine interface,

00:06:46.600 | devices that can actually be involved

00:06:48.520 | in manipulating these incredible things

00:06:50.520 | that we think of as hunger and appetite and satiety.

00:06:54.220 | So the first thing that you need to know

00:06:56.120 | about the nervous system side,

00:06:57.820 | the neural control over feeding and hunger,

00:07:00.200 | is that there's an area of your brain

00:07:01.660 | called the hypothalamus.

00:07:03.240 | It's in the forebrain, which tells you

00:07:04.780 | it's in the front of your brain,

00:07:06.040 | and it's at the base of the forebrain.

00:07:08.660 | Now, the hypothalamus contains lots of different kinds

00:07:11.380 | of neurons doing lots of different kinds of things.

00:07:13.820 | There are neurons in your hypothalamus

00:07:15.200 | controlling sexual behavior, controlling body temperature,

00:07:18.620 | controlling circadian rhythms,

00:07:20.160 | the desire to sleep or be awake,

00:07:21.800 | even neurons controlling rage.

00:07:23.940 | There are actually neurons that if we were to stimulate them

00:07:27.100 | would send you or anyone into a rage.

00:07:29.580 | They're just powerful control centers

00:07:31.600 | for the brain and body.

00:07:33.680 | There's a particular area of the hypothalamus

00:07:36.120 | called the ventromedial hypothalamus.

00:07:39.040 | And it's one that researchers have been interested

00:07:41.480 | for a long time now in terms of its relationship

00:07:44.440 | to hunger and feeding.

00:07:45.880 | And the reason is it creates these paradoxical effects.

00:07:50.480 | What do I mean by that?

00:07:51.360 | What they found was that sometimes lesioning

00:07:53.960 | or disrupting the neurons in the ventromedial hypothalamus

00:07:56.840 | would make animals or people hyperphagic.

00:07:59.200 | They would want to eat like crazy.

00:08:01.500 | And other lesions in other individuals or animals

00:08:05.700 | would make them anorexic,

00:08:06.980 | would make them not want to eat at all.

00:08:08.780 | It would make food aversive.

00:08:10.420 | So that means that the ventromedial hypothalamus

00:08:12.920 | is definitely an interesting control station

00:08:14.980 | for hunger and feeding and satiety,

00:08:16.860 | but it doesn't really tell you what's going on

00:08:18.900 | at a deeper level.

00:08:19.980 | In fact, it's a little bit confusing or paradoxical.

00:08:22.840 | It turns out that there are multiple populations

00:08:24.760 | of neurons in there.

00:08:25.600 | We're going to talk about those.

00:08:26.580 | Some are promoting feeding

00:08:28.260 | and some are promoting not feeding or not eating.

00:08:32.080 | Now, the other neural component of all this

00:08:34.540 | that you need to know about

00:08:36.140 | actually has to do with your mouth.

00:08:37.980 | So there's an area of your cortex.

00:08:39.280 | So that's a little bit further up in your brain

00:08:41.920 | called the insular cortex.

00:08:43.560 | And it processes a lot of different kinds of information,

00:08:45.960 | mostly information about what's going on inside you,

00:08:48.400 | so-called interoception.

00:08:50.420 | The insular cortex has neurons that get input

00:08:54.000 | from your mouth, from the touch receptors in your mouth.

00:08:57.560 | An insular cortex has powerful control

00:08:59.860 | over whether or not you are enjoying what you're eating,

00:09:02.520 | whether or not you want to avoid what you're eating,

00:09:04.860 | whether or not you've had enough,

00:09:06.200 | or whether or not you want to continue eating more.

00:09:09.020 | And that has to do, believe it or not,

00:09:10.860 | with the touch or sensation of eating.

00:09:13.460 | I'm very familiar with this.

00:09:14.520 | I'm one of these people I love eating so much

00:09:16.940 | that I just like the mere act of chewing.

00:09:19.740 | I like celery sticks enough.

00:09:21.740 | I'm not crazy about them, but they taste fine to me

00:09:24.020 | and I like chewing on celery sticks,

00:09:25.060 | but I actually just like chewing on them.

00:09:27.560 | I could eat all day long,

00:09:29.700 | except that it's not healthy to do that.

00:09:32.060 | But the mere act of chewing for me is very pleasurable.

00:09:35.220 | People who chew gum feel this way as well.

00:09:37.820 | And just as a point about gum or chewing,

00:09:40.140 | if you chew something like celery or cucumber slices

00:09:43.700 | or chew gum,

00:09:44.900 | provided it doesn't have any sugar or caloric content,

00:09:48.240 | it's not going to drive increased hunger.

00:09:50.940 | That generally isn't the case.

00:09:52.780 | But if you eat something with sugar, as we'll find out,

00:09:55.120 | it has a very specific action in the insular cortex

00:09:58.240 | and in other areas of your nervous system

00:09:59.640 | that promotes the desire to eat more.

00:10:01.720 | But the key point right now

00:10:03.020 | is to know that you've got these two brain areas,

00:10:04.420 | the ventromedial hypothalamus,

00:10:06.060 | that's involved in hunger and lack of hunger,

00:10:09.420 | sort of an accelerator and a break on feeding.

00:10:11.940 | And you have this insular cortex

00:10:13.660 | that gets input from your mouth and cares about chewing

00:10:16.240 | and the consistency of foods

00:10:18.260 | and all sorts of interesting things

00:10:19.660 | that are just very tactile.

00:10:21.100 | And I think most people think about the touch receptors on,

00:10:23.180 | excuse me, the taste receptors on the tongue,

00:10:25.300 | but we often don't think about

00:10:26.900 | the touch or tactile essence of food.

00:10:30.260 | The thing that comes to mind just now

00:10:31.860 | is I've gone to sushi several times

00:10:33.700 | and some people really like the urchin.

00:10:35.620 | I don't like the urchin.

00:10:36.440 | There's something about it

00:10:37.280 | that kind of creeps me out about the consistency.

00:10:38.880 | Other people love it.

00:10:40.000 | So it's highly individual and it's probably learned.

00:10:42.340 | And there's some probably cultural background to this

00:10:44.780 | if you were raised eating urchin.

00:10:46.420 | Some people love that consistency or that touch.

00:10:50.440 | So touch has a lot to do

00:10:51.680 | with whether or not you want to eat or not.

00:10:53.820 | Now let's get back to the ventromedial hypothalamus.

00:10:56.540 | Sometimes it makes animals or people want to eat more,

00:10:59.300 | sometimes less.

00:11:00.140 | So what's going on there?

00:11:01.340 | There's a classic experiment that was done

00:11:03.640 | in which researchers took two rats

00:11:06.200 | and so-called parabios to them to each other.

00:11:08.760 | What that meant is that they did a little surgery

00:11:10.580 | and they linked their blood supply

00:11:12.380 | so that they were forever physically linked to one another

00:11:15.140 | and could exchange factors in the blood,

00:11:17.620 | but their brains were separate,

00:11:18.720 | their mouths were separate,

00:11:19.680 | and they essentially did everything separately

00:11:21.940 | except that they were linked to one another.

00:11:23.260 | So they had to walk together and go to the same places

00:11:25.100 | in order to do it.

00:11:26.000 | This parabiosis experiment

00:11:29.680 | revealed something really important.

00:11:31.720 | When they lesioned the ventromedial hypothalamus

00:11:33.860 | in one of the rats that was connected to the other rat,

00:11:37.180 | that rat got very, very fat.

00:11:39.920 | It's just really obese, huge rat, super rat, jumbo rat.

00:11:43.340 | The other one, however, got very thin.

00:11:46.360 | It actually lost weight

00:11:47.920 | despite consuming the same amount of food

00:11:50.180 | that it had prior to the other one getting the lesion.

00:11:53.060 | So what does this tell us?

00:11:54.080 | This tells us that there's something in the blood

00:11:56.540 | that's being exchanged between the two animals

00:11:59.080 | because it was their blood supply that was linked,

00:12:01.700 | and that tells us that there's hormone or endocrine signals

00:12:05.420 | that are involved in the desire to eat

00:12:07.620 | and hunger and appetite.

00:12:09.260 | And so next, we're going to talk about

00:12:10.560 | what those endocrine signals are,

00:12:12.520 | and then I'm going to immediately point

00:12:14.560 | to some entry points that you can use,

00:12:16.640 | and you can use these

00:12:18.200 | even if you're not parabiosed to anything,

00:12:20.780 | and that can allow you to time your meal frequency

00:12:24.840 | and predict when you're going to be hungry or not,

00:12:27.580 | as well as drive up appetite.

00:12:29.200 | Believe it or not, there are people out there

00:12:30.520 | who are trying to eat more,

00:12:32.320 | although I think far many more people are trying to eat less

00:12:35.300 | because nowadays the data just point to the fact

00:12:38.440 | that there is essentially an epidemic of diabetes,

00:12:41.520 | type 2 diabetes, and obesity.

00:12:43.440 | And most everyone agrees now

00:12:46.080 | that maintaining a healthy body weight

00:12:48.280 | and body weight composition

00:12:49.680 | is one of the best paths to longevity

00:12:51.760 | and to just feeling very good

00:12:53.120 | and actually being able to think.

00:12:54.360 | Cognitive functioning is actually linked

00:12:56.680 | to levels of adipose tissue and so forth.

00:13:00.820 | So let's talk about the endocrine factors

00:13:03.000 | that regulate feeding, hunger, and satiety.

00:13:05.840 | One of the really exciting things to emerge

00:13:08.160 | in the science of feeding and appetite in the last 20 years

00:13:12.600 | is the discovery of another brain area,

00:13:14.580 | not just the ventromedial hypothalamus,

00:13:16.560 | but it's an area of the brain called the arcuate nucleus.

00:13:19.720 | And the arcuate nucleus

00:13:21.880 | has some really fascinating sets of neurons

00:13:24.840 | that release even more incredible molecules

00:13:28.340 | and chemicals into the blood.

00:13:30.420 | And these chemicals act as accelerators

00:13:32.640 | on feeding and appetite or breaks.

00:13:35.080 | And the really cool thing

00:13:36.320 | is that you can actually control these molecules

00:13:39.280 | through simple behaviors.

00:13:40.480 | And once you understand what these molecules are,

00:13:43.240 | you'll start to understand why that's the case

00:13:45.480 | and the control points that you have right now

00:13:48.180 | in order to control your appetite in either direction,

00:13:50.960 | increase or decrease.

00:13:52.940 | So first of all,

00:13:54.060 | there are a set of neurons in this arcuate nucleus

00:13:56.680 | called the PMOC neurons, okay?

00:13:58.920 | I don't want to get into what the acronym stands for,

00:14:01.540 | but I'll do it anyway.

00:14:03.000 | It's the pro-opiomelanocortin system, okay?

00:14:06.880 | So these are PMOC neurons, pro-opiomelanocortin.

00:14:10.900 | And if you heard Milano,

00:14:12.440 | that should tell you it has something to do with pigmentation

00:14:15.780 | in skin cells or in hair cells,

00:14:17.720 | pigmentation of some sort because of melanin.

00:14:20.800 | Last episode, I talked a little bit

00:14:22.520 | about the relationship between light, dopamine, and melanin.

00:14:26.000 | So you should already be thinking, wait,

00:14:27.520 | Milano means it probably has something to do

00:14:30.440 | with that system, and indeed it does.

00:14:33.160 | Now, the POMC neurons make something called alpha-MSH,

00:14:37.160 | melanocyte stimulating hormone.

00:14:42.000 | Alpha melanocyte stimulating hormone.

00:14:45.140 | If you don't want to remember any of the other acronyms

00:14:47.080 | and terms I've talked about this episode so far,

00:14:50.880 | do try and remember MSH, okay?

00:14:53.800 | Mouse, Sam, hamster, MSH, okay?

00:14:57.360 | MSH reduces appetite.

00:15:00.400 | And it's a powerful molecule, all right?

00:15:02.760 | So just put that on the shelf, MSH reduces appetite.

00:15:06.920 | Now there's another population of neurons

00:15:08.880 | in the arcuate nucleus called the AGRP neurons.

00:15:11.760 | And there, I'm truly not going to read you

00:15:13.660 | what that stands for 'cause it's related

00:15:15.280 | to the mouse strain it was first identified in,

00:15:17.380 | but humans have these cells as well, but AGRP neurons.

00:15:22.380 | The AGRP neurons stimulate eating.

00:15:26.980 | And anytime you are approaching food

00:15:29.760 | or you feel some excitement about food or anxiety,

00:15:32.820 | because some people actually experience

00:15:34.700 | a kind of heightened anxiety,

00:15:36.160 | some people actually get a little bit of a resting tremor

00:15:38.760 | before they eat, even if they don't have

00:15:40.160 | any sort of eating disorder,

00:15:41.520 | there's kind of a ramping up of autonomic activity.

00:15:44.660 | That's largely due to the activity of these AGRP neurons.

00:15:48.720 | So the activity in these AGRP neurons goes way up

00:15:53.600 | when animals or people are starved.

00:15:57.000 | And I don't mean starve for long periods of time,

00:15:58.680 | but I mean, when they haven't eaten for a while.

00:16:01.120 | And the activity of MSH,

00:16:04.120 | the release of MSH goes up when we've eaten.

00:16:07.400 | However, there are other things that will stimulate

00:16:10.000 | the release of things like MSH.

00:16:13.160 | So just briefly, the experimental evidence.

00:16:17.440 | If you kill AGRP neurons, animals and people stop eating.

00:16:20.600 | There are people who have lesions, they just stop eating.

00:16:22.200 | They become anorexic.

00:16:23.500 | That's actually, I know you're familiar with anorexia

00:16:25.720 | as a clinical term, but that's actually a term

00:16:27.960 | that's used in the scientific literature

00:16:29.940 | about a pattern of behavior, okay?

00:16:32.680 | As well as a clinical term, of course.

00:16:34.280 | If you were to stimulate the AGRP neurons,

00:16:36.740 | animals or people eat like crazy.

00:16:39.920 | They will eat to the point where they burst,

00:16:41.860 | which just sounds horrible, but it just tells you

00:16:43.660 | this is the accelerator on eating.

00:16:45.720 | And yes, as relationship to the ventromedial hypothalamus

00:16:48.200 | I talked about earlier,

00:16:49.020 | but I don't want to go back there just yet.

00:16:51.160 | We will circle back.

00:16:52.640 | So melanocyte stimulating hormone,

00:16:55.600 | such an interesting hormone.

00:16:57.400 | This thing can shut down the desire to eat.

00:17:00.440 | The melanocyte stimulating hormone

00:17:03.380 | is released from the medial pituitary.

00:17:07.160 | We talked about the pituitary last time.

00:17:08.740 | This is a gland that is very closely positioned

00:17:12.440 | to the hypothalamus.

00:17:13.400 | Actually, some of the hypothalamus neurons

00:17:14.960 | actually project their neural connections

00:17:17.560 | directly into the pituitary to release things

00:17:20.160 | like gonadotropins and luteinizing hormone,

00:17:22.680 | stuff we talked about last time

00:17:23.780 | in reference to testosterone and estrogen.

00:17:26.560 | But MSH is released from the medial portion

00:17:30.300 | of the pituitary and it stimulates the desire to not eat,

00:17:35.300 | to cease eating.

00:17:37.700 | What's really interesting

00:17:39.100 | is that melanocyte stimulating hormone

00:17:41.800 | is activated by ultraviolet light.

00:17:45.120 | And it's not activated by ultraviolet light to the skin

00:17:48.360 | or directly to the pituitary.

00:17:49.920 | It's activated by ultraviolet light to the eyes.

00:17:53.920 | Now, if you've been watching this podcast

00:17:56.240 | or listening to this podcast for any period of time,

00:17:58.160 | or you've heard me on other podcasts,

00:17:59.820 | or you follow my Instagram,

00:18:01.660 | I am a big fan of this whole thing of getting morning light

00:18:04.180 | in order to synchronize circadian rhythms, et cetera,

00:18:06.360 | avoiding light in the middle of the night.

00:18:09.000 | This is yet another reason why getting ample light,

00:18:13.600 | ideally sunlight, but it could be other sources of UV light

00:18:16.720 | to the eyes, stimulates MSH,

00:18:19.200 | this has been shown over and over again,

00:18:21.680 | and keeps the desire to eat or appetite in check

00:18:25.680 | in healthy ranges.

00:18:27.280 | This is also why in the spring and summer months,

00:18:30.660 | animals and people eat less.

00:18:33.300 | Now, for hibernating animals, it's different

00:18:35.000 | because the bear hibernate,

00:18:37.040 | actually bears don't truly hibernate technically

00:18:39.460 | by scientific criteria, they don't hibernate,

00:18:41.840 | but they go into a kind of torpor.

00:18:43.560 | The hibernating animals, they don't eat much

00:18:46.520 | 'cause they're in burrows or dens,

00:18:48.540 | or they're just wrapped up in a little ball

00:18:50.120 | or whatever it is that hibernating animals do.

00:18:51.720 | So they're of course going to eat far less in the winter,

00:18:53.480 | but that's a unique scenario.

00:18:54.600 | We are not hibernating animals,

00:18:55.880 | but humans generally have greater appetite

00:18:59.480 | in the cold winter months.

00:19:01.280 | It's not just because of the holidays

00:19:02.660 | and the abundance of food that we're presenting ourselves

00:19:05.140 | with, but when we get a lot of sun,

00:19:07.740 | our appetite is reduced, or at least it's easier to control.

00:19:12.260 | And that is due in part,

00:19:14.660 | because if you're getting ample sunlight to the eyes,

00:19:17.820 | it's converted into a signal for the MSH neurons,

00:19:21.440 | the neurons that release MSH, excuse me,

00:19:24.380 | these POMC neurons release MSH,

00:19:26.340 | and then MSH can bind its receptors

00:19:29.560 | and can keep the brake on appetite in check.

00:19:34.260 | So the takeaway tool from this

00:19:36.000 | is make sure you're getting enough light,

00:19:38.360 | not just in the morning, but throughout the day.

00:19:40.360 | And yes, it has to be light to your eyes,

00:19:42.160 | and blasting your eyes with sunlight or artificial light

00:19:44.520 | to the point where it's damaging or painful

00:19:46.220 | won't accelerate or improve this process.

00:19:48.200 | It's about getting photons, ultraviolet light to the eyes,

00:19:51.700 | consistently throughout the day.

00:19:53.560 | That's best accomplished by not wearing sunglasses,

00:19:56.720 | provided you can do that safely.

00:19:59.000 | And if you don't have access to enough sunlight,

00:20:01.140 | then you can do this with artificial light.

00:20:03.520 | This also points again to our old friends, the blue blockers.

00:20:06.860 | Many people know I'm not a huge fan of blue blockers,

00:20:09.820 | especially not during the daytime,

00:20:11.600 | because they block a lot of the UV

00:20:13.740 | and shorter wavelength light

00:20:15.100 | that you want and need to create alertness,

00:20:17.620 | but also to create release of MSH from the medial pituitary.

00:20:22.620 | Now, there are people out there, subcultures,

00:20:28.320 | that actually inject MSH,

00:20:31.360 | that are taking MSH or things similar to it.

00:20:34.480 | I am not suggesting people do that,

00:20:36.640 | but there are three main consequences of doing that.

00:20:40.240 | First of all, it reduces appetite, no surprise there.

00:20:42.960 | They're actually using it as a dieting drug.

00:20:45.280 | This is kind of in the underground.

00:20:47.000 | I don't know what the legal status is.

00:20:48.400 | And again, I'm not promoting that people do it.

00:20:50.200 | Two, it makes them very, very tan, which makes sense, right?

00:20:55.200 | Melanocyte stimulating hormone.

00:20:57.800 | And the third is it purportedly, never tried it,

00:21:01.780 | purportedly sends libido through the roof

00:21:04.820 | to the point where it's actually distracting

00:21:06.540 | for other activities.

00:21:08.240 | It actually can create priapism,

00:21:10.220 | which is a kind of chronic erection in males

00:21:13.380 | to the point where it actually can be physically damaging

00:21:15.800 | to the genitalia.

00:21:16.960 | So this is a drug of,

00:21:19.120 | or I don't know whether or not to call it a drug.

00:21:20.920 | It's a substance that one can regulate with healthy levels,

00:21:24.960 | with sunlight and perhaps artificial UV light.

00:21:28.560 | I have not heard much about treatments for obesity

00:21:32.500 | involving getting ample sunlight or getting ample UV light,

00:21:35.900 | but to me, the logic is just very clear.

00:21:38.720 | And so if you're pursuing those avenues,

00:21:42.040 | you certainly should talk to your physician,

00:21:44.040 | but you might want to think about

00:21:45.120 | how some of those logic hangs together.

00:21:46.960 | Absolutely fascinating hormone.

00:21:48.300 | I think most people aren't aware of it.

00:21:50.320 | And the subcultures that are aware of it

00:21:53.360 | are using it to very particular endpoints,

00:21:55.900 | and they're using it at super physiological levels.

00:21:59.120 | That's enough about that, 'cause I really don't know.

00:22:01.720 | I've talked to a few people in research,

00:22:03.920 | believe it or not, for this podcast.

00:22:05.000 | I reached out to a few people and asked whether or not

00:22:07.400 | these side effects, in air quotes,

00:22:10.280 | that I've heard about are true, and indeed they're true.

00:22:12.080 | But again, that's super physiological.

00:22:14.080 | Controlling MSH, it's actually alpha MSH levels

00:22:18.260 | through viewing ultraviolet light seems like an interesting

00:22:22.720 | and mechanistically logical thing to do

00:22:25.800 | if your goal is to keep appetite in check.

00:22:29.000 | So MSH inhibits hunger.

00:22:31.520 | Next, let's talk about a hormone peptide

00:22:33.760 | that activates hunger.

00:22:35.920 | And this is a really interesting one

00:22:37.980 | because it relates to when you get hungry,

00:22:40.880 | in addition to the fact that you get hungry at all.

00:22:43.800 | And it's called ghrelin.

00:22:45.060 | It's spelled G-H-R-E-L-I-N.

00:22:49.600 | Ghrelin is released actually from the GI tract.

00:22:53.580 | And its main role is to increase your desire to eat.

00:22:58.580 | And it does that through a variety of mechanisms.

00:23:02.000 | Part of that is to stimulate some of the brain areas,

00:23:04.800 | the actual neurons that make you want to eat.

00:23:08.040 | In addition, it creates food anticipatory signals

00:23:11.000 | within your nervous system.

00:23:11.960 | So you start thinking about the things

00:23:13.460 | that you happen to like to eat

00:23:15.380 | at that particular time of day.

00:23:17.760 | And this is fascinating.

00:23:18.800 | Ghrelin is sort of like a clock, a hormonal clock

00:23:23.040 | that makes you want to eat at particular times.

00:23:25.360 | Now, the signal for ghrelin

00:23:26.740 | is reduced glucose levels in the blood.

00:23:30.120 | We're going to talk a lot today about glucose and insulin,

00:23:33.800 | ways to manage glucose and insulin.

00:23:36.280 | But for now, the simple version of this

00:23:38.680 | is you normally want your glucose

00:23:40.840 | to be in a kind of modest range.

00:23:43.640 | And I'll explain what that range is in a little bit.

00:23:46.880 | But if it drops too low,

00:23:48.720 | ghrelin is secreted from your gut.

00:23:51.400 | It activates neurons in your brain at various locations,

00:23:54.880 | including the PMOC neurons

00:23:58.200 | and the other neurons of the arcuate.

00:24:00.800 | It also activates the VMH in particular ways.

00:24:03.920 | And it might even activate some of these neurons

00:24:06.640 | that are in the periphery in your mouth

00:24:08.440 | that actually make you kind of salivate

00:24:10.160 | and want to eat, right?

00:24:11.920 | We all know about the famous Pavlovian experiments

00:24:14.860 | of Pavlov's dogs.

00:24:15.840 | You know, they start salivating to the bell

00:24:17.320 | after the bell was presented with food,

00:24:18.600 | you remove the food,

00:24:19.440 | and then just the bell can stimulate the salivation.

00:24:21.960 | We become Pavlovian at times.

00:24:23.780 | But rarely has it ever discussed

00:24:25.640 | what the neural pathways for that are.

00:24:27.780 | And it turns out that these hormones

00:24:29.600 | that are secreted from the gut

00:24:31.080 | can stimulate the neurons to create a sensation

00:24:34.480 | and a desire for certain foods at certain times of day.

00:24:37.680 | You've done this experiment.

00:24:40.880 | If you are somebody who eats breakfast

00:24:44.120 | at more or less the same time each day,

00:24:46.180 | let's say 8 a.m., plus or minus 20 minutes,

00:24:48.960 | and then you eat lunch 1230, plus or minus 20 minutes,

00:24:52.720 | or let's say you're somebody like me

00:24:54.060 | who typically skips breakfast

00:24:56.080 | and just eats lunch usually around 1130 or 12

00:24:59.080 | or something like that,

00:25:00.200 | your ghrelin secretion will start to match

00:25:04.280 | when you typically eat.

00:25:06.480 | And it does that.

00:25:07.640 | And it's able to override the low levels of glucose

00:25:10.440 | in your bloodstream because the ghrelin system

00:25:13.440 | also gets input from a clock in your liver

00:25:18.300 | that is linked to the clock

00:25:19.960 | in your hypothalamus in your brain.

00:25:21.840 | And what this means is if you eat at regular mealtimes,

00:25:24.280 | you will start to get hungry a few minutes

00:25:25.840 | before those mealtimes.

00:25:26.920 | If you've ever wondered why

00:25:28.600 | your stomach kind of starts to growl

00:25:30.760 | because it's a particular time of day,

00:25:32.880 | you're like, "Oh, I must want to eat."

00:25:34.500 | Well, that's ghrelin.

00:25:36.000 | And for those of you that don't know

00:25:37.680 | why your stomach growls, I'll also tell you that today.

00:25:40.400 | It's actually really interesting.

00:25:42.000 | It's not at all what you expect.

00:25:44.000 | And it's not just the gurgling of liquids in your stomach.

00:25:46.680 | That's not what it is.

00:25:47.860 | It's actually a muscular phenomenon.

00:25:50.780 | So ghrelin is secreted as a kind of food anticipatory signal

00:25:55.240 | to get you motivated to go eat at regular times.

00:25:58.520 | So nowadays there's a lot of interest

00:26:00.440 | in intermittent fasting.

00:26:01.980 | There's also a lot of interest in just what meal plans

00:26:06.120 | and schedules and what to eat in general

00:26:08.320 | in order to maximize one's health and wellbeing

00:26:11.720 | and people have all sorts of cosmetic reasons

00:26:13.920 | and brain reasons and metabolic reasons

00:26:16.240 | for wanting to control this kind of stuff.

00:26:18.520 | So let's make it really simple

00:26:20.120 | by first looking at the extremes.

00:26:22.300 | Some people need to eat every two or three hours.

00:26:25.040 | They feel this, "I need to eat every two or three hours

00:26:27.280 | or else their blood sugar drops."

00:26:29.500 | In general, blood sugar doesn't drop so low

00:26:33.320 | that they truly need to eat

00:26:34.820 | in order to alleviate a blood sugar issue.

00:26:37.560 | Although sometimes that can happen.

00:26:38.760 | Some people are truly hypoglycemic, low blood sugar.

00:26:42.440 | But most people, as the blood sugar starts to head down

00:26:45.920 | towards the low-ish ranges, ghrelin is secreted.

00:26:49.560 | And so for those people, not eating on the clock

00:26:53.520 | is very disruptive to them

00:26:54.900 | because it activates these neurons in the brain.

00:26:57.480 | For people who eat once a day or twice a day

00:27:00.260 | or tend to shift their meals, they might eat a lot,

00:27:03.200 | but during a limited so-called feeding window,

00:27:05.960 | it's kind of interesting,

00:27:06.800 | humans now eat and talk about foods in ways

00:27:09.920 | that for years I used to hear about in classes and courses

00:27:13.040 | and research lectures about feeding animals,

00:27:15.240 | restricted feeding windows.

00:27:16.640 | And we owe a great deal of gratitude to Sachin Panda,

00:27:21.600 | who was a colleague of mine when my lab was in San Diego

00:27:23.920 | at the Salk Institute,

00:27:25.440 | who really is one of the pioneers

00:27:27.840 | of this restricted feeding window work

00:27:30.520 | and has done beautiful work.

00:27:31.680 | He has a book that's excellent called "The Circadian Code"

00:27:34.540 | that I highly recommend.

00:27:35.720 | And he's done a lot of important work

00:27:37.580 | on neurons in the retina that control circadian timing,

00:27:40.360 | but also the relationship

00:27:41.480 | between feeding windows and health.

00:27:44.240 | And he's sort of the major proponent out there,

00:27:48.360 | among the major proponents I should say, of circadian eating,

00:27:50.820 | that means eating during the daytime, not at night,

00:27:52.920 | or intermittent fasting,

00:27:54.060 | restricting feeding windows

00:27:55.280 | to anywhere from four to six to eight hours.

00:27:58.520 | I'll use myself as an example

00:28:00.720 | of the transition from regular feeding schedule

00:28:03.880 | to a more intermittent-ish fasting,

00:28:07.040 | although I don't really fall into true intermittent fasting.

00:28:10.160 | So I was one of these people that just got so accustomed

00:28:12.240 | to waking up and eating about an hour after I woke up,

00:28:16.280 | that to go from eating every three or four hours

00:28:19.480 | to eating twice a day, lunch and dinner,

00:28:21.920 | maybe a couple of snacks in the afternoon or something,

00:28:23.800 | at first was excruciating.

00:28:25.620 | I remember thinking like,

00:28:26.600 | this is really brutal, pushing out, feeding.

00:28:28.800 | I didn't think I could exercise unless I had eaten first.

00:28:31.580 | We now know that during most all forms of exercise,

00:28:35.440 | unless you're really focused on optimal performance,

00:28:38.300 | like you've got to hit key lifts,

00:28:39.720 | or you have to sprint at your maximum speed,

00:28:42.900 | and maybe even then, that you can exercise faster just fine

00:28:46.040 | because you're mainly relying on sources like glycogen

00:28:49.420 | from the liver, some undigested food sometimes,

00:28:52.140 | as gross as that might seem, it's true,

00:28:53.840 | as well as body fat if the exercise bout is extremely long.

00:28:58.580 | But what that means is that if you suddenly go

00:29:01.780 | from eating on a very regular schedule to skipping a meal

00:29:04.960 | or pushing your meal timing out or shifting it at all,

00:29:08.560 | you're going to have ghrelin in your system.

00:29:10.080 | And that ghrelin is going to stimulate the desire to eat

00:29:12.640 | by acting at the level of your brain.

00:29:14.400 | And it is indeed at that point, just mental.

00:29:17.140 | When we hear about just mental, just physical,

00:29:18.680 | it's really kind of the same thing

00:29:19.760 | 'cause it's all chemicals, brain and body,

00:29:21.640 | but it's the stimulation of neurons that anticipate feeding.

00:29:24.260 | You're stimulating the arcuate nucleus neurons

00:29:26.660 | that make you want to eat those AGRP neurons.

00:29:29.260 | So ghrelin stimulates the AGRP neurons,

00:29:31.920 | which makes you want to eat.

00:29:33.560 | So what can you do with this?

00:29:34.580 | What this means is if you want to start shifting

00:29:37.760 | your feeding schedule to one where you're not eating

00:29:40.380 | quite as frequently, and there are some advantages to that

00:29:43.120 | that aren't just in the biochemistry and health related,

00:29:46.560 | cellular health related things,

00:29:48.620 | but some of them include not having to think about

00:29:51.160 | or buy food, right?

00:29:52.820 | You actually don't have to think about food all day

00:29:54.800 | if you're not eating so often.

00:29:56.440 | The other is it gives you a far more social flexibility,

00:30:00.160 | right?

00:30:01.000 | You can go to a noon meeting if you have to,

00:30:02.740 | or you can go out to dinner at a particular time.

00:30:04.960 | And I guess it makes it kind of tough

00:30:06.540 | if you want to meet somebody for breakfast,

00:30:08.060 | 'cause then you're the dork who's just like

00:30:09.860 | sipping black coffee and like refusing everything.

00:30:11.800 | But anyway, I've been that dork.

00:30:14.420 | So it's one of those things you just kind of work with.

00:30:17.320 | But the fact of the matter is ghrelin secretion

00:30:20.960 | because of its relationship to the nervous system

00:30:24.140 | can be shifted by about 45 minutes per day.

00:30:28.960 | Now it's going to vary.

00:30:30.080 | Some of you have more so-called willpower, you know,

00:30:33.160 | but if you really want to just start pushing

00:30:35.840 | that first meal out or shifting it in any direction,

00:30:39.260 | some people might want to eat in the early part of the day

00:30:40.900 | and not in the evening,

00:30:42.020 | trying to shift the meal times out,

00:30:44.080 | the spacing by about 45 minutes

00:30:45.780 | is what the neural circuits that link the ghrelin system

00:30:50.360 | to the neural circuits that control feeding

00:30:52.120 | really can handle, because it's a form of neuroplasticity.

00:30:55.200 | And so what this would look like is

00:30:56.460 | if you normally you eat breakfast at eight o'clock,

00:30:58.600 | plus or minus 20 minutes,

00:31:00.260 | and you want to start eating your first meal at noon,

00:31:02.620 | you would take maybe four or five days

00:31:04.260 | and just start pushing the meal out

00:31:05.480 | by about 45 minutes to an hour each day.

00:31:07.740 | So it's not quite as painful.

00:31:09.600 | Or you can just take the plunge and just do it all at once.

00:31:12.400 | I have a colleague who was a neurosurgeon at Stanford,

00:31:16.120 | came up through my lab, he's now at Neuralink,

00:31:18.040 | and he has a great practice.

00:31:19.140 | He keeps his ghrelin system at random.

00:31:21.400 | What he does is he skips one meal per day,

00:31:24.760 | and he makes his external schedule dictate that.

00:31:27.200 | So sometimes he skips breakfast.

00:31:28.960 | Sometimes he skips lunch.

00:31:30.080 | Sometimes he skips dinner.

00:31:31.080 | He just skips one of the three major meals per day.

00:31:33.840 | And in doing that,

00:31:34.760 | the ghrelin system is always kind of kept off kilter.

00:31:37.760 | And it probably also allows him

00:31:39.200 | to have a lot of neural flexibility,

00:31:41.020 | what we call top-down control, just the knowledge,

00:31:43.240 | oh, the hunger I'm feeling isn't necessarily hypoglycemia.

00:31:47.160 | And in his case, it's almost certainly not.

00:31:49.420 | And therefore, what I'm feeling here

00:31:51.640 | is an activation of these AGRP neurons,

00:31:54.200 | and therefore I can push my meal schedule

00:31:56.020 | around however I want.

00:31:57.640 | Now, I should mention that top-down mechanisms

00:31:59.600 | are powerful, belief, motivation.

00:32:02.080 | These things can really shift neural circuits.

00:32:03.980 | We're going to talk more about that a little bit later.

00:32:06.540 | But there are also people who are genuinely hypoglycemic

00:32:10.300 | and that need to take really good control

00:32:11.720 | of their blood sugar levels and try and keep them stable.

00:32:13.980 | And so, of course,

00:32:15.360 | you want to do what's medically safe for you.

00:32:17.180 | I'm not at all recommending that people

00:32:19.460 | that suffer from hypoglycemia suddenly

00:32:22.300 | disrupt their blood sugar patterns in any direction.

00:32:25.280 | That wouldn't be healthy.

00:32:26.480 | But for most people out there

00:32:27.540 | who have reasonable blood glucose levels,

00:32:30.740 | it's kind of interesting and kind of fun

00:32:32.280 | to play with these parameters

00:32:33.760 | in order to optimize what you want to do.

00:32:35.600 | And sometimes that might change

00:32:36.600 | across the year with schedules.

00:32:38.280 | Many people find great benefit in having flexibility

00:32:42.200 | over when they eat.

00:32:43.580 | Regularity of eating equals regularity of ghrelin secretion

00:32:47.040 | equals regularity of activity of these AGRP neurons,

00:32:50.080 | meaning you will be hungry at very regular intervals.

00:32:53.220 | So that's something that you can work with.

00:32:54.500 | It's grounded in deep mechanism of hormone

00:32:57.140 | and neural systems.

00:32:58.620 | And there's a lot of modern research

00:33:00.380 | to support what I just said.

00:33:02.180 | So if MSH inhibits feeding, makes us want to eat less,

00:33:06.460 | and ghrelin makes us want to eat more,

00:33:10.140 | there's another hormone called CCK, cholecystokinin,

00:33:14.680 | that is potent in reducing our levels of hunger.

00:33:19.460 | Now, I learned about CCK back when I was an undergraduate,

00:33:22.300 | so well over 20 years ago, when it was first discovered,

00:33:27.300 | and there was a lot of excitement about CCK at that point

00:33:30.440 | as a diet drug.

00:33:32.460 | Anytime there's a molecule or a chemical

00:33:34.940 | discovered in the brain or body that can suppress feeding,

00:33:38.500 | the diet industry just goes wild.

00:33:40.900 | They think, okay, this is going to be the thing

00:33:42.200 | that's going to allow people to move from being obese

00:33:45.300 | to losing all sorts of unhealthy weight, et cetera.

00:33:48.820 | A similar phenomenon was observed with leptin.

00:33:51.700 | Leptin is a hormone that's made by body fat

00:33:55.580 | that signals to the brain when there's a lot of body fat,

00:33:58.840 | and in animals, injections of leptin

00:34:01.100 | can make fat animals thin.

00:34:02.860 | They lose a lot of adipose or fat.

00:34:05.800 | In humans, it didn't work out that way.

00:34:07.980 | It just, the studies were done,

00:34:10.020 | and leptin was successful in treating a certain rare form

00:34:12.820 | of diabetes, but it really wasn't very potent

00:34:15.480 | as an anti-obesity drug.

00:34:17.340 | Similarly, CCK has been looked at as an obesity drug,

00:34:22.340 | something to reduce obesity,

00:34:25.520 | but it had some pretty unhappy side effects,

00:34:29.120 | actually caused some pretty serious side effects.

00:34:31.400 | Now that's as a drug.

00:34:33.300 | However, CCK, when released at normal levels by your gut,

00:34:38.880 | has a powerful effect in suppressing appetite

00:34:42.160 | for a period of time,

00:34:43.500 | and there are healthy and direct ways to activate CCK.

00:34:48.400 | Now, CCK is in the GI tract.

00:34:52.060 | It's released from the GI tract,

00:34:53.900 | and its release is governed by two things.

00:34:56.640 | One is a subset of very specialized neurons

00:34:59.920 | that detect what's in the gut,

00:35:01.640 | the specific contents of the gut,

00:35:04.240 | and by certain elements of the mucosa,

00:35:07.500 | the mucus lining of the gut and the gut microbiome.

00:35:11.240 | So what's really interesting is that CCK is stimulated

00:35:16.240 | by fatty acids and particular fatty acids

00:35:20.480 | that we'll talk about, amino acids,

00:35:23.540 | and particular amino acids that we'll talk about,

00:35:26.480 | as well as by sugar.

00:35:28.920 | Now let's put sugar on the shelf for a moment.

00:35:31.040 | We're going to talk a lot about sugar

00:35:32.680 | because if CCK inhibits appetite and reduces feeding,

00:35:37.680 | and it can be triggered by fatty acids, amino acids,

00:35:42.160 | or sugars, then you might say,

00:35:43.860 | well, then eating a lot of sugar

00:35:45.380 | should make us not want to eat more,

00:35:47.240 | but we all know that eating sugar

00:35:49.180 | makes us want to eat far more.

00:35:52.120 | That's the role of a lot of sugars,

00:35:53.980 | and that has to do with a separate mechanism

00:35:55.720 | we'll talk about today.

00:35:57.500 | So which fatty acids in the gut stimulate the release of CCK?

00:36:02.100 | It turns out it's the omega-3 fatty acids,

00:36:04.760 | the ones that come from algae or krill or fish oil.

00:36:08.160 | I talked about this in the episode on nutrition

00:36:10.840 | and some of the things related to the gut microbiome,

00:36:13.720 | but I'm going to revisit that now.

00:36:15.420 | Omega-3 fatty acids and conjugated linoleic acid, CLA,

00:36:21.380 | either from food or from supplements,

00:36:24.400 | stimulate the release of CCK,

00:36:26.520 | which then reduces or at least blunts appetite.

00:36:29.780 | And I'm not talking about blunting appetite to anorexic

00:36:32.360 | levels where you don't want to eat at all.

00:36:33.920 | I'm talking about regulating appetite to the point where

00:36:36.440 | animals and people don't over-consume.

00:36:38.600 | So it's keeping appetite at a healthy level.

00:36:40.960 | The other thing that stimulates CCK that I mentioned

00:36:44.700 | are amino acids.

00:36:46.180 | So when we eat, we have the ability to break down

00:36:49.380 | different macronutrients, you know, carbohydrates,

00:36:53.860 | fats, or proteins into sugars and glucose

00:36:58.060 | that then we can convert to ATP and all that stuff

00:36:59.980 | from the Krebs cycle from high school.

00:37:01.420 | We're not going to go into that today.

00:37:02.500 | That's for a future episode.

00:37:04.140 | But amino acids are one of the things

00:37:07.420 | that we are eating for.

00:37:09.120 | Amino acids both can be used as energy

00:37:12.720 | through a process called gluconeogenesis

00:37:15.160 | of converting proteins into energy,

00:37:17.360 | or those amino acids can be broken down

00:37:19.840 | and then rebuilt into things like preparing, excuse me,

00:37:22.940 | repairing muscle tissue,

00:37:24.160 | as well as other forms of cellular repair.

00:37:26.440 | They're involved in all sorts of things related

00:37:27.760 | to protein synthesis.

00:37:29.640 | What does this mean?

00:37:31.240 | If we eat the proper amino acids at the proper levels,

00:37:35.100 | if we ingest omega-3s and CLAs, conjugated linoleic acids

00:37:38.740 | at the proper levels, or get them from supplements,

00:37:41.520 | there's a blunting of appetite.

00:37:43.400 | Appetite is kept clamped and we don't become hyperphagic.

00:37:46.480 | We don't overeat.

00:37:47.560 | We tend to eat within healthy or normal ranges.

00:37:50.600 | So this is very important because most people

00:37:55.020 | don't understand that when we're eating,

00:37:57.520 | we are basically fat foraging and amino acid foraging.

00:38:02.020 | And there are several studies now have shown

00:38:04.600 | that people and animals will essentially eat

00:38:07.160 | until they feel they've consumed enough omega-3s,

00:38:11.540 | omega-6s, CLAs, and certain amino acids.

00:38:15.640 | In other words, even if it's not conscious,

00:38:18.540 | we are eating until we trigger the activation of CCK.

00:38:21.780 | Now, there are other reasons why we shut down eating too,

00:38:23.920 | are literally the volume of food in our gut can be large

00:38:28.060 | and we can feel very distended.

00:38:29.980 | That's the physical reason, obviously.

00:38:33.420 | There are other reasons.

00:38:34.820 | Maybe we just have top-down control.

00:38:37.000 | We have knowledge that this is the end of the meal

00:38:39.960 | and we stop 'cause we have to go back to work

00:38:41.340 | or to a meeting, or we tell ourselves that we've had enough.

00:38:44.480 | But at a subconscious level,

00:38:48.040 | the gut is informing the brain via CCK and other mechanisms

00:38:52.140 | when we've ingested enough of what we need.

00:38:54.420 | And these omega-3s and CLAs and certain amino acids

00:38:58.380 | are vital for sending out that signal

00:39:00.680 | that we've had enough.

00:39:01.800 | Now, which amino acids is actually really interesting?

00:39:04.600 | We have essential amino acids

00:39:05.860 | and we have non-essential amino acids.

00:39:07.980 | Among the essential amino acids, there's one in particular

00:39:11.620 | that can trigger the release of CCK very potently,

00:39:14.740 | and that's glutamine.

00:39:16.700 | Glutamine is a very interesting amino acid.

00:39:19.220 | First of all, it's been shown in a few studies

00:39:22.220 | to play a role in bolstering the immune system.

00:39:25.340 | It can increase the number of killer cells

00:39:27.340 | in the immune system.

00:39:28.380 | It is consumed in supplement form.

00:39:31.560 | People can take a teaspoon of glutamine,

00:39:33.540 | or some people take glutamine throughout the day

00:39:35.740 | if they're really into it, or for whatever reason,

00:39:37.980 | they think they're battling off an infection

00:39:39.540 | or something of that sort.

00:39:41.060 | Glutamine can also, of course, be derived from foods.

00:39:43.580 | And you can just put into the internet,

00:39:45.940 | do an internet search and find out

00:39:47.380 | what foods are rich with glutamine.

00:39:48.740 | Some of the ones that I'm aware of off the top of my head

00:39:51.140 | are like cottage cheese and things of that sort,

00:39:53.180 | but other foods have glutamine as well.

00:39:55.140 | Once a threshold level of glutamine

00:39:59.100 | and other essential amino acids are reached,

00:40:01.420 | once a threshold level of these alpha three,

00:40:04.420 | excuse me, omega-3 fatty acids and CLAs are reached,

00:40:07.620 | CCK is released, and it helps reduce the activity

00:40:11.640 | of those AGRP neurons that promote feeding.

00:40:14.900 | So as you can see, feeding is an interplay

00:40:16.860 | between brain and body,

00:40:18.420 | and it's some of the micronutrients

00:40:20.100 | and even the breakdown of particular nutrients

00:40:22.160 | that's putting the accelerator

00:40:24.100 | or the brake on the feeding process.

00:40:26.040 | It's not just one thing.

00:40:27.700 | So from an actionable standpoint,

00:40:29.620 | you, we should probably all be trying to get

00:40:34.060 | our omega-3, omega-6 ratios correct anyway,

00:40:37.460 | because they are antidepressant.

00:40:39.180 | I talked about the peer-reviewed studies on that.

00:40:41.720 | They are healthy for the gut microbiome,

00:40:44.020 | and we should be seeking sufficient glutamine.

00:40:47.420 | Now, whether or not you decide to supplement

00:40:49.060 | with glutamine or not is up to you.

00:40:50.920 | One of the reasons why one might want to do that,

00:40:55.060 | and again, you should always check with a doctor,

00:40:56.840 | especially if you have any predisposition to cancers

00:40:59.280 | or you have cancer, many cancers and tumors like glutamine.

00:41:03.620 | So that's something to note,

00:41:04.980 | but one reason why you might want to supplement

00:41:07.620 | with glutamine or consider eating foods

00:41:09.580 | that are rich in glutamine

00:41:10.660 | isn't just to keep your appetite in healthy ranges,

00:41:13.700 | but as well, glutamine can actually reduce sugar cravings.

00:41:18.500 | So this is very interesting.

00:41:19.940 | I have a friend,

00:41:20.780 | he's an absolute chocolate sweets addict.

00:41:22.980 | He's a grown adult, but he eats candy and chocolate

00:41:26.940 | as if he was like a 14-year-old kid

00:41:29.820 | hanging out at the local convenience store.

00:41:31.620 | It's really incredible.

00:41:33.280 | And he has probably a sugar addiction,

00:41:36.940 | but he's very aware of this,

00:41:38.060 | and he's managed to kick all other addictions.

00:41:40.380 | So for whatever reason, it stimulates his brain and body

00:41:43.400 | in the ways that make him want more, but he hates this.

00:41:45.880 | It's actually quite frustrating for him.

00:41:47.900 | He's somebody who cares a lot about his health.

00:41:50.160 | He took the approach that I know many other people have

00:41:53.400 | who know about this role of glutamine

00:41:55.180 | of taking a teaspoon or a couple teaspoons of glutamine

00:41:58.760 | several times throughout the day

00:42:00.060 | or any time he craves sugar.

00:42:02.620 | And indeed, glutamine will reduce sugar cravings.

00:42:05.940 | Some people who are really on the kind of ketogenic front

00:42:09.560 | will mix it with a little bit of half-and-half,

00:42:11.120 | and down that, because I guess it makes it taste better,

00:42:13.040 | it's a little bit chalky.

00:42:14.320 | So glutamine has some very interesting properties,

00:42:16.800 | but I think for most people that aren't suffering

00:42:18.680 | from adverse levels of craving,

00:42:20.900 | making sure you're getting the right omega-3s,

00:42:24.440 | that can come from a variety of sources.

00:42:26.480 | Check out the episode we did on nutrition

00:42:29.540 | if you want to learn more about that, and CLAs,

00:42:32.920 | and making sure that you're getting enough glutamine

00:42:35.040 | is going to be important for making sure

00:42:36.440 | that the CCK signal gets through.

00:42:39.220 | The one thing I do want to mention about glutamine,

00:42:41.100 | it's a minor effect, but it alone can have a small increase,

00:42:46.100 | excuse me, it alone can increase blood sugar.

00:42:49.180 | It's not a huge increase in blood glucose,

00:42:51.360 | but because the gut takes proteins

00:42:53.540 | and breaks them down into these amino acids

00:42:55.620 | and essentially looking for glutamine and things like it,

00:42:58.460 | other essential amino acids as well,

00:43:00.280 | when you ingest glutamine or branched-chain amino acids,

00:43:03.940 | there is a small but real increase in blood glucose,

00:43:08.820 | and that's because they are essentially food,

00:43:11.300 | and there I'm talking about the supplemental version.

00:43:13.380 | So just know, glutamine can increase blood sugar slightly,

00:43:17.660 | especially diabetics should know that.

00:43:19.380 | It can reduce sugar cravings,

00:43:21.520 | and just know that what your gut is doing at a core level

00:43:25.060 | is it's forging, it's waiting,

00:43:26.580 | and it's trying to assess levels of omega-3 fatty acids,

00:43:29.620 | conjugated linoleic acid,

00:43:31.460 | and glutamine and other essential amino acids.

00:43:33.360 | You are essentially trying to eat to get these nutrients,

00:43:37.020 | and then a signal can be deployed up to your brain

00:43:39.360 | that you're not really interested in eating that much more.

00:43:42.900 | Whenever preparing an episode for this podcast,

00:43:45.060 | I'm always faced with a particular challenge,

00:43:47.260 | which is how many tools should I offer

00:43:49.440 | that involve doing something new,

00:43:51.620 | you know, a new behavior or a new exercise,

00:43:53.820 | supplements, something, things of that sort,

00:43:55.860 | and how many should be related to not doing things,

00:43:58.860 | avoiding things.

00:43:59.680 | It's never really fun to talk about all the things

00:44:01.380 | that we're supposed to avoid,

00:44:02.540 | but some of them are so powerful

00:44:04.780 | in light of the mechanisms of a given topic

00:44:08.120 | that I'd be remiss if I didn't mention them.

00:44:10.980 | So now you understand how hormones and peptides

00:44:14.220 | like CCK and ghrelin impact appetite.

00:44:16.800 | There's one particular aspect of food

00:44:20.600 | that can powerfully impact CCK,

00:44:22.740 | and I think most people, I'm guessing 99.9% of people

00:44:26.140 | out there are not aware of this,

00:44:28.300 | and it has to do with highly processed foods.

00:44:30.940 | There's a lot of reasons why one would want

00:44:32.700 | to avoid highly processed foods.

00:44:34.980 | In fact, if you're interested in that topic

00:44:36.560 | and the history of whole foods

00:44:38.860 | transitioning to highly processed foods in this country,

00:44:40.900 | I highly recommend you listen to a YouTube video

00:44:43.780 | by Dr. Robert Lustig.

00:44:45.460 | He's at University of California, San Francisco.

00:44:47.500 | It's very easy to find.

00:44:48.580 | Put Stanford, Robert Lustig.

00:44:50.480 | It was a talk hosted by Stanford.

00:44:52.380 | Gives a beautiful description of the history of this

00:44:55.540 | and why the food industry started packing in

00:44:58.140 | additional sugars and salts

00:44:59.780 | and turning foods into commodities.

00:45:01.700 | It's really fascinating.

00:45:03.420 | It has no conspiracy theory.

00:45:04.780 | It's just all scientific facts.

00:45:06.540 | It's really a wonderful lecture.

00:45:07.940 | It has millions of views.

00:45:09.340 | Should be very easy to find.

00:45:11.340 | We can provide a link to that, and we will.

00:45:13.460 | There's another reason to avoid

00:45:16.140 | highly processed foods, however,

00:45:18.220 | and that has to do with what's called emulsifiers.

00:45:22.020 | Now, many of you are familiar with emulsifiers,

00:45:23.940 | even though you don't know it.

00:45:25.220 | When you put detergent in the laundry,

00:45:28.180 | that contains emulsifiers.

00:45:31.100 | The goal of that detergent is to bring together

00:45:33.620 | fatty molecules with water molecules

00:45:36.220 | and be able to dissociate them and break them up

00:45:38.420 | to get the stains out of clothes and things of that sort.

00:45:41.220 | There are a lot of emulsifiers put into processed foods,

00:45:46.540 | and those emulsifiers allow certain chemical reactions

00:45:49.760 | to occur that extends the shelf life of those foods.

00:45:52.120 | So it's like candy bars and cereals

00:45:54.540 | and all sorts of things that are in processed foods,

00:45:57.520 | the worst of which are the typical kind of pastries

00:46:00.340 | that you see at the convenience store,

00:46:01.540 | but this extends into chips of various kinds

00:46:04.500 | and even some meats of various kinds.

00:46:06.380 | They pack this stuff into meats.

00:46:07.700 | They have names like soy lecithin and other things.

00:46:10.560 | Why are emulsifiers bad?

00:46:12.460 | Okay, there are a lot of reasons why they're bad,

00:46:14.000 | but the reason why they're bad for the mechanisms

00:46:16.340 | that we've been talking about today

00:46:17.980 | is that when you ingest those foods,

00:46:20.380 | you're bringing those emulsifiers into your gut,

00:46:23.100 | and those emulsifiers strip away

00:46:26.100 | the mucosal lining of the gut,

00:46:28.220 | and they actually cause the neurons that innervate the gut

00:46:31.540 | that extend those little processes

00:46:33.060 | we call axons into the gut to retract deeper into the gut,

00:46:37.620 | and as a consequence, you're ingesting a bunch of food,

00:46:40.780 | and the signals like CCK never get deployed.

00:46:43.900 | The signals that actually shut down hunger

00:46:46.220 | are never actually triggered,

00:46:47.640 | and so as a consequence, you want to eat far more

00:46:49.940 | of these highly processed foods.

00:46:51.680 | In addition, if you then go

00:46:53.580 | from eating a highly processed food

00:46:55.400 | to non-highly processed foods,

00:46:57.420 | you're not able to measure the amounts of amino acids,

00:47:01.220 | sugars, and fatty acids in those foods as accurately.

00:47:04.460 | You've actually done structural damage at a micro level,

00:47:07.760 | but structural damage to the mucosal lining of the gut.

00:47:11.820 | Now, this can all be repaired

00:47:13.140 | if you stay away from highly processed foods

00:47:14.980 | for some period of time,

00:47:16.260 | but the negative effects of these emulsifiers

00:47:18.500 | are quite real, so to make it really clean and simple,

00:47:22.340 | emulsifiers from highly processed foods

00:47:25.660 | are limiting your gut's ability

00:47:27.620 | to detect what's in the foods you eat

00:47:29.420 | and therefore to deploy the satiety signals,

00:47:31.800 | the signals that shut down hunger.

00:47:33.680 | In addition to that, there's a parallel mechanism at play

00:47:36.700 | that I talked about in a previous episode,

00:47:38.540 | but I'll remind you again that you have neurons in your gut

00:47:41.380 | that are sensing sugar and are sending a subconscious signal

00:47:45.960 | up to the brain via the vagus nerve,

00:47:48.360 | and those neurons trigger the release of dopamine,

00:47:52.300 | which makes you crave more of that food.

00:47:54.100 | So now you've got parallel signals

00:47:56.340 | making you want to eat more sugar,

00:47:58.240 | making you unaware of how much sugar you've eaten

00:48:00.420 | and that are disrupting the inputs to the nervous system

00:48:04.580 | that signal to the rest of your brain and body

00:48:06.360 | that you've obtained enough fatty acids

00:48:08.420 | and you've obtained enough amino acids.

00:48:10.940 | So these highly processed foods are really terrible,

00:48:14.020 | and I'm not out here to say

00:48:16.140 | never enjoy a processed food of any kind.

00:48:18.540 | I'd be a hypocrite 'cause I do eat processed foods

00:48:20.840 | from time to time, although the ones that I tend to eat,

00:48:23.140 | I try and make of the healthier variety,

00:48:24.760 | but eating whole foods has tremendous value

00:48:27.840 | and eating highly processed food

00:48:29.700 | has tremendous negative impact on the gut

00:48:32.860 | and on the gut-brain axis.

00:48:34.500 | And so recently there was a paper

00:48:36.900 | that came out in Cell, Cell Press Journal.

00:48:38.700 | It's kind of the apex of cell journals, which is phenomenal.

00:48:41.980 | This paper showed that ingesting highly processed food

00:48:45.580 | leads to more intake of not just highly processed foods,

00:48:49.400 | but other types of food in general.

00:48:51.820 | There was kind of an overeating compensation

00:48:54.080 | generally across foods

00:48:55.720 | for people that consume these highly processed foods.

00:48:57.700 | And there are a lot of other reasons

00:48:58.860 | to avoid highly processed foods.

00:49:00.420 | So again, I don't like to focus too much on the do nots.

00:49:02.940 | I like to arm you with tools to do,

00:49:05.320 | but I think this visual of certain foods

00:49:08.040 | and these emulsifiers actually stripping away

00:49:10.160 | some of the critical lining of your gut

00:49:12.540 | and disrupting the hormone signaling

00:49:14.280 | to the brain controlling feeding is important enough

00:49:17.420 | and cryptic enough, meaning it hasn't been talked about,

00:49:21.020 | it works at a subconscious level,

00:49:23.080 | and that it's important that people are aware of it

00:49:25.960 | so they can make decisions about what they do want to eat

00:49:27.900 | or not want to eat for themselves.

00:49:29.900 | Before moving on, I just want to say one more thing

00:49:31.980 | about highly processed foods.

00:49:34.220 | There was an absolutely beautiful study

00:49:36.800 | done by my colleague, Chris Garner at Stanford,

00:49:39.220 | exploring whether or not certain diets

00:49:41.140 | were better than others.

00:49:42.180 | They looked at vegan, vegetarian, omnivore.

00:49:45.880 | I don't know if they looked at all meat or not,

00:49:47.820 | but they looked at the different forms of diets,

00:49:49.340 | intermittent fasting, et cetera.

00:49:50.780 | And they essentially found that whichever diet

00:49:54.180 | people adhered to, whichever one they followed,

00:49:57.220 | was equivalent to the others provided that they followed it,

00:50:00.380 | they lost the equivalent amount of weight.

00:50:02.440 | There really wasn't a strong effect of the food type

00:50:06.260 | or the pattern of eating, et cetera.

00:50:08.240 | However, in a study like that,

00:50:09.900 | adherence is very high because people are a part of a study.

00:50:12.900 | And for many people, the ability to adhere

00:50:15.900 | to a certain eating plan is one of the most,

00:50:19.020 | if not the most powerful determinants

00:50:21.440 | of whether or not a given diet,

00:50:23.100 | meaning nutritional plan, works.

00:50:25.520 | Now, this thing about highly processed foods, however,

00:50:28.400 | is really diabolical because it truly says,

00:50:32.180 | and I think the recent data in cell metabolism

00:50:35.020 | and other journals really proves

00:50:36.500 | that a calorie is not a calorie.

00:50:38.540 | That's absolutely absurd because of these emulsifiers

00:50:41.060 | and the content of these highly processed foods.

00:50:44.300 | In fact, the data in humans points to this.

00:50:47.820 | So what they did is they took inpatient adults,

00:50:50.740 | so they had total control over their food intake,

00:50:52.980 | and they received either ultra-processed

00:50:55.180 | or unprocessed diets for 14 days as a short study.

00:50:58.400 | The diets were matched for calories, sugar, fat, fiber,

00:51:02.140 | and macronutrients, so everything else was matched.

00:51:04.140 | Just processed or non-processed is the major variable.

00:51:08.740 | And basically what they found is that the people

00:51:12.360 | who were eating the processed food diet

00:51:14.580 | happened to eat much more, right?

00:51:16.840 | This was after this period of putting them on either diet

00:51:19.340 | and clamping for all other variables.

00:51:21.260 | Then they would eat much more,

00:51:23.060 | and the body weight changes were much more.

00:51:25.140 | And those body weight changes were such

00:51:28.780 | that they couldn't be accounted for

00:51:30.020 | by just increased calories.

00:51:31.660 | So the bottom line is that highly processed foods

00:51:34.680 | are just bad for you.

00:51:35.560 | They increase weight gain.

00:51:36.920 | They disrupt the lining of your gut

00:51:38.700 | in a way that disrupts things like CCK

00:51:40.980 | and proper satiety signals.

00:51:42.680 | And they contain a bunch of things, in particular sugars,

00:51:46.180 | but other things as well,

00:51:47.620 | that disrupt not just the hormonal systems,

00:51:50.000 | but also the neural systems that control the desire to eat

00:51:53.480 | after the diet is done.

00:51:55.120 | So there's just so many reasons

00:51:56.540 | why these highly processed foods are terrible,

00:51:59.560 | and they can explain a lot of the ill health effects

00:52:01.820 | that we've seen in the last 50 years,

00:52:03.860 | not just in the United States, but all over the world.

00:52:05.780 | The enormous increase in diabetes, juvenile diabetes.

00:52:09.160 | It's just remarkable how far down the path of dad,

00:52:14.080 | we've gone, and it's clear,

00:52:16.080 | it's almost a smoking gun what the cause of this is.

00:52:18.560 | If you'd like to learn more about that,

00:52:20.360 | please refer to the Lustig lecture.

00:52:22.160 | He also spells out why non-processed foods

00:52:27.080 | is far more economical in terms of just at the level

00:52:30.640 | of the household or individual,

00:52:32.020 | as well as at the societal level.

00:52:33.820 | Really interesting stuff.

00:52:34.820 | I highly recommend you check it out.

00:52:36.520 | So now let's move on to some other hormones

00:52:38.440 | that regulate hunger and satiety, in particular insulin.

00:52:43.200 | Now you've probably heard of insulin before.

00:52:45.140 | Insulin is the thing that's lacking in type one diabetics.

00:52:48.540 | That's why they have to inject insulin whenever they eat.

00:52:50.740 | The reason they have to do that is because when they eat,

00:52:53.320 | their foods are broken down into glucose.

00:52:55.820 | And in order to shuttle glucose

00:52:57.580 | to the appropriate tissues in the body,

00:52:59.660 | and also to keep glucose levels in check, you need insulin.

00:53:03.380 | So the simplest way to think about insulin and glucose

00:53:06.900 | is that when you eat, that food is broken down into sugars.

00:53:12.200 | That's true whether or not it's fats or it's sugars,

00:53:15.360 | or eventually if it's proteins,

00:53:17.880 | they are oxidized into fuels, as we say.

00:53:20.300 | And those fuels can be used, as the name fuel implies,

00:53:24.960 | into energy, they're eventually made into ATP.

00:53:27.220 | There's a bunch of biochemical steps

00:53:28.380 | that we're not going to go into today,

00:53:29.840 | but that's essentially how it works.

00:53:30.820 | You break down food into glucose.

00:53:32.800 | Now, if you're ketogenic,

00:53:33.960 | we'll talk about that in a little bit,

00:53:36.080 | but in general, you eat, food is turned into glucose.

00:53:41.480 | Your blood sugar needs to be kept in a particular range.

00:53:44.360 | Hypoglycemic means too low, hyperglycemic means too high,

00:53:48.540 | and what they call the euglycemic, EU glycemic,

00:53:53.520 | is the healthy range.

00:53:55.840 | Now, what those healthy ranges are,

00:53:58.200 | in general, the healthy range, the euglycemic range,

00:54:02.140 | is about 70 to 100 nanograms per deciliter,

00:54:06.360 | but most of you aren't walking around

00:54:07.600 | with a glucose monitor.

00:54:08.920 | Some of you are, but most of you are not.

00:54:12.080 | The more important question for us to address right now

00:54:14.480 | is why is it important that glucose

00:54:16.480 | be kept at a particular level?

00:54:18.040 | Once you understand that, keeping glucose in check

00:54:21.960 | starts to have a rationale behind it,

00:54:24.200 | and the ways to do that start to make a lot more sense.

00:54:27.320 | So the reason is, if glucose levels get too high

00:54:32.320 | because of the way that our cells, in particular neurons,

00:54:35.920 | interact with glucose, high levels of glucose

00:54:40.400 | can damage neurons, it can actually kill them.

00:54:42.520 | You can start getting what are called peripheral,

00:54:44.920 | excuse me, neuropathies.

00:54:46.640 | One of the symptoms of some forms of diabetes

00:54:49.120 | is that people start losing the sensation of touch

00:54:52.600 | in their fingers or their hands or their feet,

00:54:55.040 | and they can start going blind.

00:54:56.560 | There's diabetic retinopathies.

00:54:59.640 | So it's very important that insulin

00:55:02.320 | manage your glucose levels.

00:55:04.600 | Now, there's also type 2 diabetes

00:55:06.680 | where there's insulin secreted from the pancreas,

00:55:10.900 | but people are insulin insensitive.

00:55:13.500 | There's a disruption in the receptors,

00:55:15.680 | and insulin insensitivity

00:55:18.200 | isn't quite the same as having no insulin at all,

00:55:20.760 | but it parallels some of the same mechanisms.

00:55:22.920 | Now, type 1 diabetes is often picked up

00:55:25.040 | because someone has a sudden weight loss

00:55:28.520 | because they're not processing blood sugar

00:55:30.380 | the same way they were before.

00:55:31.600 | Type 2 diabetes is often, although not always,

00:55:34.500 | associated with being overweight and with obesity.

00:55:37.960 | Both of them are challenging conditions.

00:55:40.820 | Type 2 diabetes almost always can be managed

00:55:43.440 | by managing one's weight.

00:55:45.600 | And of course, there are prescription drugs

00:55:50.040 | and supplements that can help manage those.

00:55:51.860 | We're going to talk about all of that.

00:55:53.640 | But for most people that don't have diabetes,

00:55:56.200 | the important thing is to manage glucose,

00:55:58.080 | to keep it in that euglycemic range.

00:56:01.200 | And there are a number of different ways to do that.

00:56:03.460 | Some of them are behavioral, some of them are diet-based,

00:56:06.880 | and some of them are based

00:56:09.040 | on supplements or prescription drugs.

00:56:10.680 | So let's talk about those now.

00:56:12.160 | So if you eat, and in particular, if you eat carbohydrates,

00:56:15.920 | blood glucose goes up.

00:56:17.320 | If you eat fats, blood glucose goes up to a far less degree.

00:56:20.640 | And if you eat proteins, depending on the protein,

00:56:23.920 | it'll eventually be broken down for fuel

00:56:26.120 | or assembled into amino acid chains for protein synthesis

00:56:29.400 | and repair of other tissues and bodily functions.

00:56:32.600 | But glucose goes up and then is kept in range.

00:56:37.300 | When you are hungry, you secrete a different hormone,

00:56:40.700 | and that's called glucagon.

00:56:42.440 | And glucagon's main role is to pull stores of energy

00:56:47.440 | out of the liver and the muscles.

00:56:50.820 | And once those are depleted,

00:56:52.820 | you'll eventually tap into body fat, okay?

00:56:55.680 | So, and this is for people

00:56:56.740 | that have a typical blood glucose range,

00:56:58.500 | so that 70 to 100 euglycemic range.

00:57:02.080 | So the two kind of push and pull systems

00:57:05.320 | that we're going to think about now to keep this simple

00:57:07.480 | is that you have the insulin system managing glucose,

00:57:11.320 | and you've got the glucagon system pulling energy

00:57:14.520 | out of your liver and muscles for immediate fuel,

00:57:18.200 | and eventually you'll pull fuel out of body fat

00:57:22.440 | if you've been active for a very long time

00:57:24.200 | and all your glycogen stores are depleted

00:57:26.460 | or close to depleted.

00:57:28.360 | So what does this all mean?

00:57:29.960 | There's a lot of important biochemistry

00:57:32.600 | and a lot of important cellular processes involved

00:57:34.720 | in whether or not you're anabolic or catabolic,

00:57:37.140 | whether or not you're breaking things down

00:57:38.420 | or building things up.

00:57:39.520 | Let's talk about feeding in a simpler way, however,

00:57:44.340 | and let's weave the tools to manage blood glucose

00:57:47.560 | to keep it in check as we do that.

00:57:50.240 | So let's say you had a meal,

00:57:52.280 | and that meal consisted of rice, a carbohydrate,

00:57:57.500 | some meat or fish, let's say a piece of salmon,

00:58:00.700 | and some vegetable, some fibrous vegetable

00:58:02.840 | like asparagus or cabbage or something like that.

00:58:05.240 | If you were to eat all of that at once,

00:58:09.020 | you take a bite of one, a bite of the other,

00:58:10.900 | you mix it up, one of these,

00:58:12.520 | it all ends up in the same place kind of people,

00:58:14.520 | mix it all up,

00:58:15.980 | then you will experience an increase in insulin

00:58:18.520 | and increase in blood glucose that's moderately fast.

00:58:23.400 | It's going to increase pretty quickly.

00:58:25.760 | What's remarkable is that the order that you consume

00:58:28.820 | each macronutrient has a pretty profound influence

00:58:31.360 | on the rate of insulin and glucose secretion into the blood

00:58:36.360 | and how quickly those levels rise.

00:58:39.000 | So if you, we'll make it really simple,

00:58:41.140 | if you were to eat the rice first,

00:58:42.520 | your glucose would rise in a sharp spike,

00:58:44.920 | especially if it doesn't contain any fats

00:58:46.680 | to slow the absorption.

00:58:48.540 | Now, that might be good if you're very hungry

00:58:51.480 | and you want to get an increase in glucose.

00:58:53.880 | In fact, this is the reason why you're often served bread

00:58:56.840 | before meals because it's,

00:58:58.660 | and sometimes it's bread and butter,

00:59:00.540 | but, or chips before meals or appetizer

00:59:02.840 | are designed to get your blood glucose going up high

00:59:05.120 | because big steep increases in blood glucose

00:59:07.880 | tend to promote the desire to consume more glucose.

00:59:12.240 | And this also relates to the dopamine system

00:59:14.800 | and the way that something tasty in the mouth

00:59:17.060 | and sugar in the gut and fats and sugars in the mouth

00:59:20.740 | trigger the activation of a lot of systems

00:59:23.400 | in the brain and body to consume more of whatever you have

00:59:26.380 | or whatever is available to you.

00:59:28.520 | So the basic idea is that eating carbohydrates

00:59:33.100 | and or fats early in a meal

00:59:35.040 | will give a steep rise in blood glucose.

00:59:37.320 | However, if you were to eat the fibrous thing first,

00:59:40.960 | so a lot of chewing, but not a big rise in blood glucose,

00:59:43.520 | 'cause in general there's,

00:59:44.440 | unless it's laden with sugar or something,

00:59:45.920 | we're just talking about some vegetable, fibrous vegetable,

00:59:50.640 | that will actually blunt the release of glucose

00:59:54.640 | until you eat the fish and the rice.

00:59:57.300 | But believe it or not,

00:59:58.320 | it will actually blunt the glucose increase

01:00:01.240 | that the rice would cause.

01:00:02.980 | Now, I'm not talking about neurotically

01:00:04.480 | eating each macronutrient separately in sequence.

01:00:06.660 | I'm just trying to give you a picture

01:00:07.880 | of what's happening ordinarily.

01:00:09.940 | So what this means is

01:00:11.280 | if you feel a lot of food-related anxiety,

01:00:14.900 | or you feel you're one of these people

01:00:16.480 | that you can kind of sense like your blood sugar

01:00:19.540 | increasing very quickly,

01:00:21.080 | a lot of people can sense this, some people can't,

01:00:23.120 | has a lot to do with how well they manage their blood sugar

01:00:25.520 | as well as some of the psychological factors.

01:00:27.520 | And yes, there are family and historical reasons

01:00:29.800 | where I've got friends who had a lot of siblings

01:00:31.800 | and when they sit down to eat,

01:00:32.980 | they have to really suppress the desire

01:00:34.420 | to not beat up everyone else at the table

01:00:37.700 | and take all the food.

01:00:38.540 | It's sort of like not,

01:00:39.920 | it's hard for them to understand

01:00:42.360 | that there's plenty to go around because of their upbringing.

01:00:45.380 | So there are psychological top-down effects.

01:00:48.760 | A lot of the psychology around food

01:00:50.340 | is geared towards getting people to be relaxed

01:00:52.080 | when they eat and these sorts of things.

01:00:53.760 | But these blood sugar effects are real,

01:00:55.560 | just cellar and basic biochemistry

01:00:58.700 | of how the body manages sugars ingested into the blood.

01:01:02.800 | So what does this all mean?

01:01:04.580 | It means that if you want a steep increase in glucose,

01:01:07.720 | you are very, very hungry,

01:01:08.800 | then you should eat the carbohydrate-laden food first,

01:01:12.360 | or you should eat a bunch of macronutrients combined.

01:01:15.000 | So that would be like the hamburger or the sandwich,

01:01:17.320 | the bread, the whatever's in that sandwich altogether.

01:01:20.780 | Usually that's protein and vegetables as well.

01:01:23.880 | If you want to have a kind of more modest increase

01:01:28.760 | in glucose or you want to blunt the increase in glucose,

01:01:31.200 | then have the, at least some of the fibrous thing first,

01:01:35.440 | and then the protein, and then the carbohydrate,

01:01:38.140 | you will notice that your blood glucose

01:01:39.760 | will rise more steadily

01:01:42.560 | and that you'll achieve satiety earlier in the meal,

01:01:45.800 | or at least you won't get this huge peak.

01:01:48.160 | It's sort of the Thanksgiving meal effect.

01:01:50.360 | Some of you are international,

01:01:51.440 | so if you don't celebrate Thanksgiving as a time of year

01:01:54.200 | where, used to be the one time a year or two times a year

01:01:57.280 | where Americans would give themselves permission

01:01:58.920 | to eat enormous meals.

01:02:00.840 | Now that seems to happen a lot more often,

01:02:02.820 | but there is this effect of you're full

01:02:04.640 | and yet you're hungry for more.

01:02:05.900 | That's because your blood glucose has gone through the roof

01:02:07.800 | and it's triggered a number of other mechanisms.

01:02:10.100 | There's also usually a lot of alcohol consumption

01:02:13.880 | and alcohol itself, because it's a sugar,

01:02:17.640 | will increase blood glucose very, very sharply.

01:02:21.080 | It depends on the alcohol.

01:02:22.520 | Some alcohols have more sugar than others,

01:02:24.440 | but basically what you're trying to avoid

01:02:26.120 | are steep increases in blood sugar.

01:02:27.600 | And the order that you eat foods

01:02:28.960 | has an enormous impact on that.

01:02:31.160 | The other thing that has an enormous impact

01:02:32.800 | on how long and shallow or how steep that curve of glucose

01:02:37.800 | is depends on whether or not you recently were moving,

01:02:42.780 | are moving, or start moving after you eat.

01:02:45.560 | So it turns out that your blood glucose levels

01:02:48.900 | can be modulated very, very powerfully by movement.

01:02:52.340 | If you did any kind of intense exercise

01:02:55.020 | or even just walking or jogging or cycling,

01:02:58.120 | anything before you eat,

01:02:59.140 | your blood glucose levels will be dampened somewhat.

01:03:01.240 | And that has to do with the release of something called,

01:03:04.500 | some people call it GLUT4, which sounds like glutton.

01:03:07.020 | Other people call it GLUT4.

01:03:08.940 | These are things that are involved in shuttling glucose

01:03:11.820 | to particular cells in the body,

01:03:13.320 | namely toward muscle and glycogen stores

01:03:15.240 | and away from body fat stores.

01:03:17.360 | It has to do a sequestering of glucose from the blood.

01:03:19.720 | The point is that if you're somebody who struggles

01:03:22.360 | with blood sugar regulation,

01:03:23.520 | in addition to getting your body weight in a healthy range,

01:03:27.120 | doing all the other sorts of things

01:03:28.360 | that you should be doing,

01:03:29.560 | the key thing is to try and get some movement

01:03:34.280 | sometime circa meal.

01:03:36.060 | Now, very few people can actually eat and walk

01:03:38.200 | at the same time, although I do it all the time,

01:03:40.440 | not because I'm trying to regulate my blood sugar,

01:03:42.060 | but just 'cause I tend to be busy, I eat and drive.

01:03:44.040 | I'm busy if I'm not giving this podcast or sleeping,

01:03:47.400 | I'm eating, except the early part of the day when I fast.

01:03:50.540 | But the bottom line here is that if you, for instance,

01:03:53.680 | take a 30-minute walk after a meal,

01:03:57.300 | your blood glucose will be blunted

01:03:59.160 | in ways that are beneficial.

01:04:01.100 | If you have exercised in the recent hours before a meal,

01:04:04.740 | that can be beneficial.

01:04:05.740 | The order that you consume foods is beneficial.

01:04:07.840 | And there are a few things that you can consume

01:04:09.880 | that can also adjust blood glucose levels.

01:04:12.220 | So let's talk about those,

01:04:13.360 | but I thought it was important to really tamp down

01:04:15.800 | that it's not just what you eat,

01:04:18.040 | we talked about that before,

01:04:19.120 | but also the order that you eat those things,

01:04:21.320 | believe it or not, whether or not you combine

01:04:22.940 | macronutrients, carbohydrates, proteins, and fats,

01:04:25.920 | and fibrous vegetables,

01:04:27.940 | and whether or not you've moved recently,

01:04:31.000 | the higher intensity of the movement,

01:04:32.440 | the greater the GLUT4 increase,

01:04:35.040 | and the more that the blood glucose will be blunted

01:04:37.440 | and you'll shuttle more of that to glycogen and muscle stores

01:04:40.160 | and even just moving after a meal,

01:04:42.440 | even just a calm, easy walk can really adjust the ways

01:04:46.340 | in which blood sugar regulated for the better.

01:04:49.080 | I don't want to perseverate on this processed foods,

01:04:52.680 | hidden sugars thing too much,

01:04:54.160 | but understanding now a little bit

01:04:56.680 | about how insulin and glucose work,

01:05:00.320 | you can probably imagine why hidden sugars

01:05:03.000 | are such an attractive thing from the standpoint

01:05:05.180 | of processed food manufacturers,

01:05:07.120 | because if they can put sugar in that you can't even taste,

01:05:10.980 | that sugar is going to amplify the amount of glucose,

01:05:13.880 | it's going to increase the rate of glucose increase

01:05:16.480 | into your bloodstream and it's going to promote more feeding.

01:05:19.720 | So in that case, you're really being tricked,

01:05:21.600 | it's not that you're actually reaching

01:05:22.960 | for the additional appetizer

01:05:24.440 | and your blood glucose is going up,

01:05:26.160 | the food that you ate is actually increasing your appetite

01:05:29.400 | as you eat it, it's a positive feedback loop.

01:05:32.920 | So don't want to demonize those any more

01:05:34.760 | than I already have,

01:05:35.720 | but you should be aware that these things are happening

01:05:38.520 | at the level of your bloodstream and brain.

01:05:40.720 | The other thing I'd like to address for a moment

01:05:44.480 | is this notion of stable blood sugar

01:05:47.140 | versus labile blood sugar or unstable blood sugar.

01:05:50.620 | Some people just have stable blood sugar,

01:05:53.520 | they can go long periods of time without eating

01:05:55.680 | and feel fine, other people get really shaky,

01:05:57.920 | really jittery and or when they do eat,

01:06:01.480 | they feel really keyed up, sometimes they'll even sweat,

01:06:04.640 | sometimes their vision will go blurry

01:06:06.920 | and some of that can actually be

01:06:08.760 | because they've become hyperglycemic.

01:06:12.000 | And those effects that you experience

01:06:14.520 | when you are hyperglycemic are the early warning signs

01:06:18.240 | of the kinds of things that damage neurons

01:06:20.280 | and lead to the really terrible stuff

01:06:22.440 | they talked about before like peripheral neuropathies.

01:06:24.520 | Now it takes some time for those things to occur,

01:06:26.260 | those neuropathies to occur,

01:06:27.760 | but whether or not your blood sugar is all over the place

01:06:30.100 | or whether or not it's stable

01:06:32.020 | can be impacted by a number of things.

01:06:34.720 | One of those things is exercise.

01:06:36.840 | So these days there's a lot of interest

01:06:38.920 | in what they call zone two cardio,

01:06:40.340 | which is that kind of steady state cardio

01:06:42.060 | where you can just nasal breathe even at pretty high output

01:06:45.540 | where you could maybe have a conversation,

01:06:47.740 | although I'm such a huge proponent of nasal breathing

01:06:50.840 | during exercise, most forms of exercise,

01:06:52.840 | especially zone two cardio

01:06:54.400 | that you probably shouldn't be talking

01:06:56.520 | while you're doing that cardio

01:06:57.760 | unless it's absolutely essential.

01:06:59.920 | But periods of zone two cardio

01:07:03.200 | that last anywhere from 30 minutes to an hour

01:07:06.980 | or sometimes more for you endurance athletes

01:07:09.120 | can create positive effects on blood sugar regulation

01:07:13.280 | such that you, people can sit down

01:07:17.120 | and enjoy whatever it is, the hot fudge sundae

01:07:19.600 | or whatever the high sugar content food is.

01:07:21.900 | And blood glucose management is so good,

01:07:24.840 | your insulin sensitivity is so high, which is a good thing,

01:07:28.560 | that you can manage that blood glucose

01:07:30.900 | to the point where it doesn't really make you shaky,

01:07:33.940 | it doesn't disrupt you.

01:07:35.640 | And to say nothing of the weight related issues

01:07:39.400 | or the adipose fat gain, et cetera,

01:07:41.760 | that's a separate issue 'cause people vary there.

01:07:43.900 | But basically doing zone two cardio

01:07:47.600 | for 30 to 60 minutes three to four times a week

01:07:50.740 | makes your blood sugar really stable.

01:07:52.880 | And that's an attractive thing for a variety of reasons.

01:07:55.620 | On the flip side, high intensity interval training

01:07:58.680 | or resistance training, AKA weight training,

01:08:01.200 | are very good at stimulating the various molecules

01:08:04.560 | that promote repackaging of glycogen.

01:08:07.100 | So sprints, heavy weightlifting, circuit type weightlifting

01:08:10.900 | provided there's some reasonable degree of resistance.

01:08:13.680 | Those are going to trigger all sorts of mechanisms

01:08:16.100 | that are going to encourage the body

01:08:18.800 | to shuttle glucose back into glycogen,

01:08:22.060 | convert into glycogen into muscle tissue,

01:08:23.760 | restock the liver, et cetera.

01:08:25.640 | Depleting one's glycogen actually takes some time.

01:08:28.380 | If you do a couple sets of tricep extensions

01:08:31.100 | and some crunches, you're not depleting your glycogen.

01:08:33.440 | Glycogen depleting workouts are very high intensity.

01:08:37.600 | Generally they're less than an hour or so,

01:08:39.720 | but those are the sort that are going to lead

01:08:42.720 | to big increases in the kinds of enzymes

01:08:44.780 | and metabolic pathways that are going to repack glycogen

01:08:47.440 | and shuttle most things towards restorage of foods,

01:08:51.400 | not into adipose tissue, not into fat,

01:08:53.460 | but taking glucose and making it into fuels

01:08:55.860 | that you can access later for more of that high intensity

01:08:58.600 | activity.

01:08:59.560 | And I should mention that one of the advantages

01:09:01.480 | of high intensity interval training

01:09:04.240 | or weightlifting of various kinds is that it also,

01:09:09.120 | it causes long standing increases in basal metabolic rate.

01:09:13.280 | I don't want to go too far down this path

01:09:14.760 | 'cause we're going to do an entire month

01:09:16.200 | on human performance and athletic performance,

01:09:19.680 | but it's not just the increases in muscle

01:09:22.680 | that increase metabolism because muscle burns more energy

01:09:26.560 | than other types of tissues, except your brain,

01:09:28.640 | which truly burns the most energy

01:09:31.500 | and is the main reason why your basal metabolic rate

01:09:34.760 | is what it is.

01:09:35.640 | Well, high intensity training, so it could be sprints,

01:09:39.680 | it could be a high intensity interval training

01:09:41.220 | of different kinds, it could be weight training,

01:09:43.180 | also has an effect of increasing thermogenesis

01:09:47.220 | even long after you've completed the exercise.

01:09:50.520 | So there's a long tail, there's a kind of post exercise

01:09:53.580 | metabolic effect that's also beneficial.

01:09:55.860 | So it's not an either or,

01:09:57.400 | it's really that high intensity interval training

01:09:59.240 | and resistance training and things of that sort

01:10:01.600 | are very good for one reason and the zone two cardio

01:10:05.680 | is very good for other reasons.

01:10:07.080 | And now you can see why it's just a healthy thing

01:10:09.360 | and why most people should probably be doing exercise

01:10:11.420 | most days of the week, if not every day of the week.

01:10:14.180 | If your goal is to manage blood glucose

01:10:17.500 | and your goal is to manage some of the metabolic factors

01:10:21.100 | that control repackaging of glycogen

01:10:23.240 | and encouraging excess glucose

01:10:25.680 | to not get diverted into body fat stores.

01:10:28.400 | We haven't talked a lot about lipids today

01:10:30.620 | and that's because most of today's discussion

01:10:32.660 | is about hormones and insulin is the dominant hormone

01:10:36.120 | in terms of mobilizing and managing glucose in the body,

01:10:39.980 | at least for most people, but fats are very important

01:10:44.400 | and there's just a little anecdote about fats

01:10:47.240 | that I think will be useful in thinking about

01:10:49.060 | why you want to manage what they call the LDL or HDL ratios.

01:10:52.900 | And this is deserving an entire episode,

01:10:54.920 | many perhaps even several episodes,

01:10:57.220 | but some of you may be familiar with LDLs and HDLs,

01:11:01.540 | some of you may not, the LDL is low density lipoprotein.

01:11:05.320 | This is the one that you don't want it to be too high,

01:11:08.140 | Costello's dreaming, he's barking,

01:11:09.840 | he loves all forms of cholesterol,

01:11:13.060 | but that's just Costello dreaming.

01:11:15.640 | So LDLs are the ones that you want to keep low,

01:11:18.020 | you don't want those to go excessively high.

01:11:19.960 | HDLs, the high density lipoproteins

01:11:22.320 | are the ones that are the so-called healthy lipoproteins.

01:11:26.080 | That's all fine and good,

01:11:28.600 | but you might ask yourself, what are they doing?

01:11:30.960 | What is the actual role of these things?

01:11:32.840 | And why would you want healthy levels of HDL

01:11:36.680 | and not too much LDL?

01:11:38.460 | Well, one of the reasons is that fats don't like water,

01:11:43.460 | they are hydrophobic.

01:11:45.600 | And yet you need to move fats in your bloodstream,

01:11:48.920 | all tissues in your body need fats, they need cholesterols,

01:11:52.720 | last episode we talked about how cholesterol

01:11:54.400 | is a precursor to the sex steroid hormones,

01:11:56.520 | estrogen and testosterone and other hormones as well.

01:11:59.760 | Well, HDL and LDL actually coat fats

01:12:04.280 | to allow them to be transported through the bloodstream.

01:12:07.120 | They do a number of other things as well,

01:12:09.000 | but HDL is a key component of the delivery system

01:12:13.260 | that brings those fats to the liver, ovaries,

01:12:16.400 | testes and adrenals.

01:12:18.380 | In other words, having adequate levels of HDL is good

01:12:22.280 | because it allows fats to be delivered to the tissues

01:12:24.800 | that manufacture testosterone, estrogen, cortisol

01:12:29.000 | in healthy levels and the liver.

01:12:31.460 | So this is why when LDLs are too high,

01:12:35.300 | what's happening is you're not getting fats

01:12:37.240 | to the correct tissues and you can get buildup of fats

01:12:40.040 | like fatty liver disease and some of these things can happen.

01:12:44.020 | High sugar content can even lead

01:12:45.600 | to some of these fatty liver conditions

01:12:47.880 | that's starting to happen.

01:12:48.720 | This is actually the first time in human history perhaps

01:12:51.280 | that we're aware of anyway,

01:12:52.780 | that we're starting to see liver conditions

01:12:55.360 | that normally were associated only with severe alcoholism

01:12:59.140 | starting to come from sugar content.

01:13:00.560 | So what does this mean?

01:13:01.560 | This means keep your LDL and HDL ratios proper.

01:13:04.120 | You want those HDLs in order to deliver fatty molecules

01:13:08.840 | to the very tissues that use cholesterol

01:13:10.900 | in order to manufacture hormones.

01:13:13.040 | So how do you keep LDLs and HDLs in their proper ratios?

01:13:16.120 | Well, a lot of people don't realize this,

01:13:19.000 | but the debate about dietary cholesterol

01:13:22.680 | and its relationship to LDL and HDL ratios

01:13:26.080 | is a barbed wire debate.

01:13:28.480 | I don't want to get into it right now.

01:13:30.020 | There are still a lot of open questions

01:13:32.280 | as to how much dietary cholesterol

01:13:35.120 | impacts LDL and HDL ratios.

01:13:36.920 | I don't want to get into that now.

01:13:38.880 | I'm not taking a stance either way.

01:13:40.860 | But what is very clear

01:13:42.520 | is that having highly elevated glucose

01:13:45.840 | consuming too much sugar or not managing glucose

01:13:48.680 | in your body through some of the mechanisms

01:13:50.360 | that we've been talking about up until now

01:13:52.840 | can also negatively impact LDL/HDL ratios.

01:13:56.560 | So managing glucose goes way beyond

01:13:59.140 | just managing blood sugar

01:14:00.920 | and making sure that you don't lay down too much body fat,

01:14:03.480 | making sure your metabolism stays high,

01:14:04.920 | making sure you're not getting jittery at meals.

01:14:06.500 | It also has to do with making sure

01:14:08.880 | that you're creating enough of the molecules, HDL,

01:14:12.140 | and not too many of the molecules, LDL,

01:14:15.660 | that are going to disrupt the delivery of things

01:14:18.640 | to the organs of your body

01:14:20.160 | that allow you to make healthy levels

01:14:21.780 | of testosterone, estrogen, and so forth.

01:14:24.120 | If that wasn't clear, let me make this ultra simple.

01:14:27.060 | You want healthy levels of HDL

01:14:29.360 | and you want low levels of LDL

01:14:31.800 | because if you have ovaries,

01:14:33.600 | it will allow the fats that need to get to the ovary

01:14:38.120 | to produce estrogen to get there.

01:14:40.780 | And if you have testes,

01:14:42.080 | it will allow the fats and the cholesterol molecules

01:14:45.440 | that you need in order to manufacture testosterone

01:14:49.640 | to get to the testes.

01:14:51.280 | As well, in order to have proper adrenal function

01:14:54.200 | and proper liver function,

01:14:55.440 | you want HDL and LDL in the healthy, correct levels.

01:14:59.200 | So now we've talked a lot about behavioral tools

01:15:01.860 | and the underlying biological mechanisms

01:15:04.080 | that justify those tools in particular circumstances.

01:15:07.760 | Now I'd like to turn to supplements and prescription drugs

01:15:11.040 | that regulate the hormone systems

01:15:13.500 | controlling feeding and satiety.

01:15:16.000 | There are a huge number of these.

01:15:17.540 | Some have more powerful effects than others.

01:15:19.960 | There are two that I want to describe

01:15:21.740 | because they've been getting a lot of attention recently.

01:15:24.960 | First of all, there's a prescription drug, metformin,

01:15:28.240 | which was developed as a treatment for diabetes

01:15:30.720 | and it works potently to reduce blood glucose.

01:15:34.440 | It has dramatic effects in lowering blood glucose.

01:15:38.560 | Metformin involves changes to mitochondrial action

01:15:43.560 | in the liver.

01:15:44.520 | That's its main way of depleting or reducing blood glucose.

01:15:49.440 | And it does so through the so-called AMPK pathway

01:15:52.260 | and it increases insulin sensitivity overall.

01:15:56.820 | Metformin is a powerful drug.

01:15:58.720 | In fact, I'm surprised that so many people

01:16:01.460 | have sought it out given that most of the people

01:16:05.440 | that I'm aware of that sought it out are not diabetic.

01:16:07.700 | I think for diabetics, it seems to be a useful drug.

01:16:10.780 | For non-diabetics, it can also, of course,

01:16:13.280 | lower blood glucose.

01:16:14.520 | It also has the potential to make people hypoglycemic,

01:16:17.680 | genuinely hypoglycemic.

01:16:19.520 | So you really need to approach metformin with caution.

01:16:23.000 | I get a little concerned when I hear about people

01:16:25.360 | blasting metformin simply because fasted states

01:16:28.920 | or low blood sugar states are healthy.

01:16:31.300 | Doing that pharmacologically can have long-standing effects.

01:16:34.880 | You really want to approach that with caution.

01:16:37.580 | Now there's a comparable drug.

01:16:41.160 | It really should be called a drug,

01:16:42.540 | but it's non-prescription.

01:16:44.200 | That's also in fairly prominent use out there

01:16:46.280 | called berberine, B-E-R, B-E-R-I-N-E, berberine, correct.

01:16:54.280 | So berberine is a really interesting compound.

01:16:58.100 | Its actions very much mimic metformin.

01:17:01.340 | So let's talk about berberine for a second.

01:17:04.060 | Berberine actually comes from various plants and tree bark.

01:17:08.380 | It is sold in supplement stores.

01:17:10.120 | It's sold online.

01:17:11.400 | It is, as far as I know, unregulated.

01:17:13.520 | It is powerful.

01:17:14.600 | If you're going to experiment with berberine,

01:17:16.400 | you definitely want to talk to your doctor

01:17:18.240 | and you want to approach it with caution.

01:17:20.800 | It also works to activate the so-called AMPK pathway.

01:17:25.800 | AMPK, by the way, stands for adenosine monophosphate

01:17:28.680 | activated protein kinase, AMPK,

01:17:30.840 | and it inhibits a protein tyrosine phosphase, 1B pathway.

01:17:34.100 | I think that's enough nomenclature.

01:17:36.460 | It activates a certain pathway that's associated

01:17:39.040 | with fasting and low blood glucose.

01:17:41.920 | The effects of berberine are, as far as I can tell,

01:17:46.340 | when looking at the literature, are very similar,

01:17:49.680 | if not identical, to metformin.

01:17:51.800 | Now, the number of studies out there on this are many,

01:17:57.000 | so I'm just going to review a few of them

01:17:58.600 | and their major effects.

01:18:00.080 | As always, I invite you to check out examine.com.

01:18:03.840 | It's a wonderful website where you can put in

01:18:05.480 | any supplement or compound or biological goal,

01:18:08.900 | for that matter, and it will list out the various effects

01:18:11.800 | in the human effect matrix, so studies on humans,

01:18:14.460 | if they're available, and it will tell you

01:18:17.360 | whether or not there's strong effects or weak effects

01:18:18.960 | or modest effects, and it will point

01:18:20.460 | to the specific subject population, a wonderful resource.

01:18:24.040 | So berberine, not surprisingly, has very strong effects

01:18:27.820 | in lowering blood glucose.

01:18:28.960 | There are four studies on this.

01:18:30.920 | In fact, they say that berberine is one of the more,

01:18:33.280 | if not the most effective supplements

01:18:35.160 | for lowering blood glucose.

01:18:36.360 | It talks about dosages there, although I'll just mention

01:18:39.600 | that I've tried berberine, and the dosages that are typical

01:18:43.240 | on the bottle of most supplements is much higher

01:18:48.400 | than I needed.

01:18:49.240 | So when I took berberine, two things happened.

01:18:51.840 | First of all, I got a pretty splitting headache.

01:18:55.640 | It gave me pretty vicious headaches.

01:18:57.220 | So for me, it was a no almost immediately.

01:18:59.860 | The other thing is I became so hypoglycemic

01:19:03.260 | that in order to get my blood sugar back up,

01:19:05.420 | I think I ate something like 10 donuts,

01:19:07.520 | and I didn't feel like I had ingested all that much sugar.

01:19:10.880 | It was really kind of weird.

01:19:11.860 | I was hyperphagic for sugar.

01:19:13.200 | I was craving sugar, craving sugar,

01:19:14.560 | and I was very thirsty as well.

01:19:16.320 | And so I don't want to promote any bad behavior,

01:19:19.660 | but I know that certain people use this

01:19:21.440 | when they've overeaten sugars,

01:19:22.980 | or they're doing their cheat days,

01:19:24.360 | something that I'm personally just not a fan of,

01:19:26.820 | and they want to keep their blood sugar in check,

01:19:28.620 | or they know they're going to consume a huge meal.

01:19:30.200 | They'll take berberine to keep blood glucose clamped,

01:19:32.960 | and it does do that.

01:19:34.440 | It has very strong effects.

01:19:36.240 | Three peer-reviewed studies on HbA1c levels.

01:19:39.520 | HbA1c is something that can be measured in a blood test

01:19:42.640 | that is sort of an average readout

01:19:44.880 | of your blood sugar levels over the previous

01:19:47.000 | two or three months, sometimes shorter period,

01:19:49.080 | but that's mostly what HbA1c is about.

01:19:53.680 | So it radically decreases your blood sugar levels.

01:19:58.480 | It actually lowers cholesterol.

01:20:00.200 | It acts, remember, on the liver,

01:20:02.080 | and the liver is involved in cholesterol metabolism.

01:20:06.200 | And remember, it's both sugars, blood glucose,

01:20:09.280 | and dietary fats, perhaps, it's still heavily debated,

01:20:14.800 | in terms of how your blood total cholesterol,

01:20:17.280 | HDL and LDL, are regulated.

01:20:18.820 | So it seems to lower total cholesterol,

01:20:20.800 | and it seems like it lowers HDL and LDL in parallel.

01:20:25.360 | So that's interesting.

01:20:27.080 | One study showed a minor increase in HDL,

01:20:29.480 | the so-called good cholesterol.

01:20:31.200 | Insulin levels dropped, not surprising.

01:20:32.920 | Another study showed a slight decrease in LDL.

01:20:35.740 | Those seem to be kind of minor.

01:20:37.000 | Here's a kind of interesting one,

01:20:38.160 | just to help you remember berberine,

01:20:39.760 | as if the fact that it comes from tree bark

01:20:41.720 | isn't trigger enough to remember it.

01:20:44.740 | Direct contact of berberine on canker sores

01:20:48.040 | seems to eliminate canker sores very quickly,

01:20:50.120 | which is kind of cool.

01:20:51.220 | I haven't had canker sores in a few years,

01:20:52.600 | but when I did get them, they are extremely painful.

01:20:55.700 | Don't like those.

01:20:56.540 | So that's kind of interesting.

01:20:57.480 | And there's some study references there.

01:20:59.800 | I find it amazing that these compounds exist.

01:21:01.680 | You've got this prescription drug metformin,

01:21:03.400 | and then you've got berberine, the stuff from tree bark,

01:21:05.720 | and they have effects that are

01:21:07.000 | essentially equivalent to one another.

01:21:08.840 | So again, I'm not promoting their use

01:21:11.020 | or even their exploration, but those compounds do exist.

01:21:14.440 | They're out there.

01:21:15.480 | And check out examine.com if you'd like to learn more.

01:21:17.840 | Certainly do your reading, do your homework

01:21:19.840 | before you start just popping the stuff.

01:21:21.840 | And if you have hypoglycemia or hyperglycemia,

01:21:26.840 | be especially careful.

01:21:28.940 | And also do understand that dosages

01:21:32.480 | and dose requirements vary.

01:21:33.820 | So if you do go down this path,

01:21:36.500 | really approach things carefully.

01:21:37.920 | Always start with the lowest amount

01:21:40.320 | that you could get away with.

01:21:41.800 | For me, the headache thing just made it a no-go.

01:21:44.160 | I do keep a bottle of it in full disclosure

01:21:47.880 | in the odd chance that I feel like eating a ton of donuts.

01:21:52.480 | It's not so much about not ingesting the calories.

01:21:55.920 | It's just that I don't like the feeling

01:21:57.160 | of being hyperglycemic, the blurry vision,

01:21:59.320 | just feeling lousy.

01:22:00.720 | I do love donuts.

01:22:02.580 | Other things that impact blood glucose in supplement form.

01:22:05.520 | Chromium has been shown in 29 studies to have a minor,

01:22:10.000 | I want to emphasize a minor effect

01:22:11.380 | on reducing blood glucose.

01:22:13.080 | Things like L-carnitine,

01:22:14.240 | something we've talked about here on the podcast before

01:22:16.260 | in terms of its relationship to power output

01:22:19.220 | in ATP production for both aerobic and anaerobic exercise,

01:22:23.280 | as well as sperm quality and egg quality.

01:22:26.920 | We talked about that long ago.

01:22:28.600 | Things like panache ginseng can have positive effects on,

01:22:34.680 | I should say, can have effects

01:22:37.120 | of reducing blood glucose slightly.

01:22:39.280 | I don't want to give a valence to or judgment

01:22:41.740 | to whether or not it's positive or negative.

01:22:43.160 | Here's something that's interesting

01:22:44.360 | that you should know about.

01:22:45.200 | Caffeine has very reliably been shown

01:22:49.340 | to increase blood glucose just a little bit, okay?

01:22:53.440 | So I always thought that caffeine would drop blood glucose,

01:22:56.500 | but it actually can increase blood glucose just slightly.

01:23:00.380 | Things like magnesium.

01:23:02.140 | Talked about magnesium as a tool

01:23:04.480 | for enhancing the passage into sleep.

01:23:07.920 | In particular, magnesium threonate and biglycinate.

01:23:10.740 | Magnesium can also have a modest reduction in blood glucose.

01:23:14.800 | You're starting to get the impression

01:23:15.720 | everything reduces blood glucose,

01:23:17.140 | but that's certainly not the case.

01:23:18.400 | And then a couple episodes ago

01:23:21.440 | when we were discussing nutrition,

01:23:22.480 | we talked about artificial sweeteners,

01:23:24.060 | sucralose, aspartame, nutra-sweet.

01:23:27.320 | Some of those are generic names.

01:23:29.720 | Some of those might be brand names

01:23:31.040 | and how they have negative effects on the gut microbiome

01:23:33.760 | and that's supported by a number of studies.

01:23:35.280 | There's one artificial sweetener.

01:23:37.920 | It's stevia, S-T-E-V-I-A,

01:23:41.280 | which seems to lower blood glucose just slightly.

01:23:44.080 | And I still can't find data on whether or not stevia

01:23:48.640 | impacts the gut microbiome in either direction.

01:23:52.060 | Many of the things that I consume

01:23:53.380 | do have small amounts of stevia in them.

01:23:55.020 | So I'd love to know if anyone out there

01:23:56.860 | is aware of quality peer-reviewed research

01:23:59.500 | as to whether or not stevia impacts the gut microbiome

01:24:03.420 | similarly or differently from other artificial sweeteners.

01:24:07.500 | Please let me know.

01:24:08.340 | Please send me the references.

01:24:09.360 | I'd really appreciate it.

01:24:10.200 | You can put it in the comment section on YouTube

01:24:11.840 | or elsewhere.

01:24:12.680 | Comment section on YouTube would be the best place.

01:24:16.180 | So stevia seems to lower blood glucose a little bit,

01:24:18.520 | which makes it kind of an attractive artificial sweetener

01:24:21.560 | if one is going to use artificial sweeteners.

01:24:24.780 | But remember, sweet taste itself stimulates

01:24:27.600 | the desire to eat, which will increase more blood glucose.

01:24:30.280 | So I'm guessing that they probably cancel each other out.

01:24:32.260 | So you have to think logically about these things.

01:24:35.020 | Vitamin B3, so some of the B vitamins do indeed

01:24:37.920 | stimulate appetite by triggering increases in blood glucose.

01:24:41.460 | Vitamin B3 in particular, I don't know if B6 does.

01:24:44.260 | Things like zinc seem to lower blood glucose.

01:24:46.460 | And then there've been an enormous number of other things

01:24:49.080 | that have been tested for their roles in blood glucose.

01:24:53.480 | Apple cider vinegar, anything acidic.

01:24:56.100 | This is well known now that any kind of acidity,

01:24:59.340 | so it could be lemon juice or lime juice

01:25:01.260 | or apple cider vinegar, lowers blood glucose slightly.

01:25:04.740 | Some of those can also have other effects

01:25:06.500 | that we're not talking about today.

01:25:08.140 | So that's kind of interesting

01:25:09.240 | because there's a movement now towards creating,

01:25:13.860 | sort of people talk about becoming more alkaline,

01:25:16.100 | you know, I hate to break it to you,

01:25:18.000 | but you don't really want your body to be too alkaline.

01:25:21.260 | You want to stay in the right pH or else you start,

01:25:23.900 | there are conditions that make you more alkaline.

01:25:26.700 | You don't want to be too acidic or too alkaline.

01:25:29.280 | If you see a beverage or something that purports

01:25:33.580 | that ingesting that beverage

01:25:34.980 | is going to make you more alkaline,

01:25:37.060 | that is absolutely false.

01:25:38.380 | There's no evidence for that.

01:25:39.740 | It's impossible biochemically, it's just marketing.

01:25:42.860 | But nonetheless, ingesting foods that are acidic

01:25:47.180 | can make some slight adjustments to the pH of the gut

01:25:51.860 | in ways that can slow or alter the absorption of foods

01:25:55.860 | and can blunt blood glucose.

01:25:57.940 | You can try this sometime if you want.

01:25:59.260 | If ever you're feeling kind of over sugared out,

01:26:01.340 | like you ate something with too much sugar,

01:26:03.080 | you can drink a small amount of lemon juice

01:26:05.060 | mixed with water or lime juice.

01:26:06.460 | And you'll notice that it will blunt

01:26:08.260 | that kind of hyperglycemic effect just a little bit.

01:26:11.420 | Again, you don't want to use this as a medical tool,

01:26:14.360 | but the effect is fairly potent.

01:26:17.140 | And then, excuse me.

01:26:18.860 | And then there are a number of other things like capsaicin

01:26:21.880 | and hot chili peppers that will lower blood glucose.

01:26:24.060 | The list goes on and on.

01:26:25.580 | The most powerful one is absolutely berberine and metformin,

01:26:30.240 | but that's really heavy caliber stuff.

01:26:32.960 | And the other ones I mentioned have more minor effects.

01:26:36.100 | I do want to mention,

01:26:37.580 | because I'm sure some of you out there

01:26:38.860 | are curious about the ketogenic diet,

01:26:40.340 | I'm going to do an entire episode

01:26:42.020 | about ketosis and the brain and the body.

01:26:44.700 | But the ketogenic diet has been shown in 22 studies

01:26:49.700 | to have a notable decrease on blood glucose.

01:26:51.800 | And that is not surprising

01:26:53.140 | because the essence of the ketogenic diet

01:26:56.700 | is that you're consuming very little or zero of the foods

01:27:00.820 | that promote big spikes in insulin and glucose.

01:27:04.180 | If you consume enough protein,

01:27:06.380 | some of that protein can be converted into glucose,

01:27:09.180 | of course, through gluconeogenesis.

01:27:11.140 | But the ketogenic diet has very strong support

01:27:14.320 | for its role in regulating blood sugar, which is glucose.

01:27:19.240 | But the specific effects of the ketogenic diet

01:27:22.440 | and one particular effect that I'll address later,

01:27:25.380 | but I'll mention now,

01:27:26.840 | which is the ability of the ketogenic diet

01:27:29.580 | to adjust thyroid hormone levels

01:27:32.980 | in ways that make it such

01:27:34.520 | that if you return to eating carbohydrates

01:27:36.580 | after being in ketosis for too long,

01:27:38.780 | you don't manage thyroid and carbohydrates as well.

01:27:41.860 | That has been shown as well.

01:27:43.460 | So we're going to dive deep into ketosis

01:27:45.140 | in a future episode.

01:27:46.260 | So for you ketonistas out there, don't worry.

01:27:48.800 | I certainly have nothing against ketogenic diet.

01:27:51.180 | I actually don't have anything for

01:27:52.940 | or against any particular nutrition plan.

01:27:54.780 | I know what works for me,

01:27:56.140 | at least at this stage of my life,

01:27:57.380 | and I'll update it if I need to.

01:27:58.940 | I'm simply trying to get you as much information

01:28:00.900 | as I possibly can

01:28:02.380 | so that you can navigate through that landscape

01:28:04.820 | in a way that's in keeping with your particular goals.

01:28:08.520 | So now you understand a lot about blood sugar

01:28:10.900 | and how it's managed

01:28:12.060 | and the ways that you can manage it better

01:28:13.940 | depending on your particular needs.

01:28:16.380 | This is also a good opportunity for us to look back

01:28:19.860 | at some of the medical literature

01:28:22.020 | because it really points to just how far we've come

01:28:25.340 | in terms of understanding these important mechanisms.

01:28:28.020 | And it points us in the direction

01:28:29.980 | of some actionable protocols.

01:28:32.440 | So diabetes, which is these huge increases in blood glucose

01:28:37.440 | because there's no insulin,

01:28:40.020 | was known about as early as 1500 BC,

01:28:43.380 | which is just incredible.

01:28:45.220 | And the way physicians then understood

01:28:49.760 | that certain people had high blood glucose

01:28:51.940 | without actually knowing what blood glucose was

01:28:54.400 | is that they would take the urine of particular patients

01:28:57.380 | and they'd find that ants preferably moved toward

01:29:01.780 | and consumed the urine of certain patients and not others.

01:29:06.300 | And they understood that there was something in that urine

01:29:09.320 | that was correlated with the sudden weight loss

01:29:11.460 | and some of the other probably very unfortunate health

01:29:14.140 | symptoms that these people were experiencing.

01:29:17.200 | So they knew that there was something in blood and urine.

01:29:21.080 | But you might not be asking yourself, wait, that's urine.

01:29:25.180 | But as I tell every kid that I meet, two things,

01:29:29.940 | I tell a kid, your brain is here.

01:29:31.940 | I make them point to their head.

01:29:33.140 | And then I tell them, do you know what?

01:29:35.120 | Do you know that your urine is actually filtered blood?

01:29:37.900 | And they usually go, hmm.

01:29:39.500 | I get parental permission to do this first,

01:29:41.520 | but most adults don't realize that your urine

01:29:44.380 | is actually just filtered blood.

01:29:46.660 | And that's why if you see blood in your urine,

01:29:49.660 | that's a problem.

01:29:50.700 | You want to filter the blood, but urine is filtered blood.

01:29:54.360 | Now, this business of measuring blood sugar from the urine

01:29:59.360 | has been something that lasted way beyond

01:30:03.000 | these early stages of 1500 BC.

01:30:06.240 | Turns out that as late as 1674,

01:30:09.260 | physicians at Oxford University were figuring out

01:30:13.760 | who had pathologically high levels of blood glucose

01:30:18.400 | by analyzing their urine.

01:30:20.840 | And again, they were measuring the sweetness of their urine.

01:30:23.640 | But, and this is medical fact,

01:30:25.580 | they would do this by taking urine samples

01:30:27.460 | from different patients and tasting them.

01:30:31.300 | And they developed an intuitive sense

01:30:34.460 | of what excessively sweet urine was relative

01:30:39.000 | to the other urines that they had tasted.

01:30:40.700 | So for those of you that are in the medical profession

01:30:42.620 | or those of you that are seeking out the medical profession,

01:30:45.340 | do understand this is not done anymore.

01:30:48.060 | And you can also just reflect on how far we've come

01:30:51.320 | in terms of the medical profession itself

01:30:53.740 | in our ability to measure things from the blood

01:30:55.780 | and measure things from urine

01:30:57.140 | without having to ask ants which urine is sweeter

01:31:02.140 | or ask oneself which urine is sweeter.

01:31:04.940 | So indeed, we are making progress as a species.

01:31:08.420 | Before we close out today,

01:31:09.660 | I want to talk about one more tool

01:31:11.400 | that many of you will probably find useful.

01:31:14.400 | I certainly have.

01:31:15.940 | I'm a big consumer of caffeine,

01:31:18.140 | although I don't consume a ton of it.

01:31:20.180 | I consume it very consistently.

01:31:21.740 | So I'm big on consuming mate,

01:31:24.440 | which is a strong caffeinated tea.

01:31:27.340 | And I generally do that early in the day,

01:31:30.140 | although I do delay about two hours after I wake up

01:31:32.440 | for reasons I've talked about in previous episode

01:31:34.440 | to maintain that nice arc of alertness and focus.

01:31:37.520 | I do drink black coffee as well, mushroom coffee as well.

01:31:40.500 | I love that stuff.

01:31:41.740 | But mate, also called yerba mate,

01:31:45.120 | is an interesting compound because unlike coffee,

01:31:49.440 | it has been shown to increase something

01:31:50.820 | called glucagon-like peptide, GLP-1,

01:31:54.860 | and increase leptin levels.

01:31:56.620 | Now, we didn't talk a lot about glucagon today.

01:31:58.580 | Glucagon is really elevated in the fasting state.

01:32:01.580 | I mentioned that it's sort of the opposite of insulin

01:32:04.560 | in kind of rough terms.

01:32:06.420 | That's one way to think about it.

01:32:08.940 | But GLP-1 or glucagon-like peptide one

01:32:13.260 | is increased by ingesting mate,

01:32:15.740 | and it acts as a pretty nice appetite suppressant.

01:32:19.800 | Now, I'm not trying to suppress my appetite.

01:32:22.100 | I like to eat, as I mentioned before,

01:32:24.240 | but it works really well to stimulate the brain

01:32:27.920 | and to give you a level of alertness

01:32:31.100 | and to do a lot of the things that coffee does.

01:32:33.160 | It also contains electrolytes.

01:32:34.940 | So we, meaning our neurons and our brain,

01:32:39.400 | run on a variety of factors, electrical activity

01:32:42.900 | and chemical transmission, et cetera,

01:32:44.280 | but they require adequate levels

01:32:46.340 | of sodium, potassium, and magnesium.

01:32:48.820 | Actually, if you were to learn the biology

01:32:51.820 | or the physiology of the action potential,

01:32:53.580 | the firing of a neuron,

01:32:54.920 | something we teach every first-year neuroscience student,

01:32:57.180 | and I'd be happy to teach you if you're interested,

01:33:00.340 | you'll hear about sodium rushing into cells

01:33:03.200 | and potassium entering and leaving cells

01:33:06.360 | in order to allow neurons to communicate.

01:33:08.720 | Electrolytes are critically important

01:33:11.320 | for the function of the nervous system.

01:33:13.460 | And many things that act as diuretics

01:33:16.420 | that promote excretion of water, like caffeine,

01:33:20.220 | can also take electrolytes out

01:33:22.560 | along with, in particular, sodium.

01:33:24.380 | And sometimes the lightheadedness or the brain fog

01:33:26.780 | that people experience isn't just

01:33:28.380 | because electrolytes are low,

01:33:29.540 | but because they're kind of out of balance.

01:33:31.860 | So I like mate because it has electrolytes, it has caffeine.

01:33:36.060 | It stimulates the release of this glucagon-like peptide,

01:33:38.780 | GLP-1, and it's been a big help to me

01:33:40.980 | in extending that early morning fasting window

01:33:43.660 | out to about noon or so when I eat my first meal.

01:33:46.580 | It also just tastes really good.

01:33:48.020 | I don't drink it out of the gourd,

01:33:49.420 | even though I have Argentine lineage.

01:33:50.860 | The gourd to me is, it's just kind of an inconvenience.

01:33:53.820 | I drink it out of a mug.

01:33:55.740 | There's no promotional here.

01:33:56.980 | I have no relationship to any yerba mate plantations

01:34:00.140 | or companies.

01:34:01.960 | I just happen to really like the stuff.

01:34:03.780 | And the fact that glucagon-like peptide-1 is enriched

01:34:08.540 | or is released more when you drink mate,

01:34:11.500 | and the fact that GLP-1 can regulate blood sugar

01:34:15.020 | in ways that keep your blood sugar in that,

01:34:17.860 | we called you got glycemic, not too high, not too low mode,

01:34:22.200 | is one reason why ingesting mate is attractive to me.

01:34:26.040 | If you go to South America, what you'll see,

01:34:28.420 | especially among Uruguayans, but also Argentines,

01:34:31.020 | is people actually carry a thermos of this stuff with them

01:34:34.140 | around and bring it to meals in restaurants.

01:34:36.540 | And that's just considered cultural convention.

01:34:38.380 | It's not unusual to see that.

01:34:40.100 | So we don't see that so much here in the States,

01:34:41.940 | but I happen to really love this stuff.

01:34:43.540 | I brew my own because that's the most economical way

01:34:46.380 | to do it.

01:34:47.220 | And I really enjoy it.

01:34:48.520 | It can be a little bitter for some people.

01:34:50.940 | The real key there, if you want to know the mate trick,

01:34:53.220 | is to not use water that's really boiling hot.

01:34:55.860 | You go just shy of boil,

01:34:57.200 | and then it doesn't have that same kind of tobacco-like

01:35:01.980 | or really acidic flavor to it.

01:35:04.700 | It's a little bit, just a little bit sweeter,

01:35:07.020 | although not quite sweet.

01:35:08.580 | So Yerba Mate GLP-1 can manage, in healthy ways,

01:35:13.140 | leptin levels, glucose levels, and glucagon levels

01:35:16.200 | in ways that if it serves you, you might want to try.

01:35:19.700 | So once again, we covered an enormous amount of material

01:35:23.220 | focused on how hormones regulate feeding, hunger,

01:35:27.300 | and when one feels they don't need to eat,

01:35:30.280 | so-called satiety that you've had enough.

01:35:33.040 | As always, we covered a lot,

01:35:34.980 | but I could not be exhaustive about all the information

01:35:38.680 | related to this topic.

01:35:39.860 | It's just so vast.

01:35:41.100 | For instance, we did not talk about thyroid hormone,

01:35:43.900 | an extremely important hormone and pathway

01:35:47.020 | in the body and brain.

01:35:48.380 | We are going to do an episode related to thyroid

01:35:50.620 | and tools to regulate thyroid, I promise.

01:35:53.100 | Having seen this episode,

01:35:54.660 | you will be able to digest that material with far more ease.

01:35:58.820 | We also didn't talk about the fact that testosterone

01:36:02.700 | and estrogen can impact blood glucose in ways

01:36:05.420 | that are opposite to one another,

01:36:07.200 | that when estrogen levels are high,

01:36:09.220 | appetite tends to be reduced.

01:36:11.620 | When testosterone levels are high,

01:36:13.700 | appetite tends to increase.

01:36:15.140 | So there are all sorts of interesting interplays

01:36:17.220 | between the various hormones,

01:36:18.720 | but that's much too much of a deep dive for now.

01:36:21.660 | Right now, we've just focused today mainly

01:36:24.460 | on things like ghrelin,

01:36:26.180 | on things like melanocyte-simulating hormone,

01:36:29.260 | incredible, powerful hormone that can suppress appetite,

01:36:32.940 | on things like cholecystokinin that comes from the gut

01:36:36.540 | and can suppress appetite,

01:36:38.280 | on things like food emulsifiers,

01:36:40.500 | on the fact that when you're eating,

01:36:42.540 | you are amino acid seeking,

01:36:44.700 | even though you might not realize it,

01:36:46.380 | that you are also seeking out particular fatty acids,

01:36:49.540 | in particular the conjugated linoleic acids and omega-3s.

01:36:53.400 | So I've tried to give you a number of actionable tools.

01:36:55.840 | Many of them are behavioral.

01:36:58.720 | Some of them are based on supplements

01:37:00.940 | or even prescription drugs.

01:37:02.500 | Again, always do what's best for your health

01:37:04.560 | and do that in company with a healthcare professional.

01:37:07.560 | I'm not a physician.

01:37:08.400 | I don't prescribe anything.

01:37:09.840 | I'm a professor.

01:37:11.160 | I profess a lot of things.

01:37:12.420 | And I try and share with you what I think

01:37:13.880 | to be the best high quality peer-reviewed literature.

01:37:16.660 | So that's what I've done today.

01:37:18.200 | Really appreciate your time and attention.

01:37:20.400 | Many of you have continued to ask

01:37:21.920 | how you can help support the podcast,

01:37:23.800 | and we really appreciate the question.

01:37:26.080 | There are several ways to do that.

01:37:27.320 | The first is to like a video that you've seen,

01:37:31.000 | if you like it, and please subscribe to the YouTube channel.

01:37:34.360 | That's perhaps the most important thing

01:37:35.740 | about the YouTube channel.

01:37:37.080 | As well, leave us a comment.

01:37:38.540 | If you leave us a comment in the comment section,

01:37:40.220 | that helps us, and please ask questions.

01:37:43.120 | Those questions and your comments

01:37:44.600 | do inform content of future episodes.

01:37:46.900 | We read them all, except the negative ones.

01:37:49.440 | I'm just kidding.

01:37:50.260 | We read them all.

01:37:51.600 | In addition, please subscribe on Apple and/or Spotify

01:37:55.960 | or both, if you like.

01:37:57.500 | And on Apple, you have the opportunity

01:37:59.260 | to leave us up to a five-star review,

01:38:01.160 | if you feel we deserve that.

01:38:02.400 | Apple also lets you leave a comment,

01:38:04.520 | some feedback for us as well.

01:38:06.760 | Please do check out our sponsors

01:38:08.220 | that we mentioned at the beginning of the podcast.

01:38:10.920 | That's the best way perhaps to support the podcast.

01:38:13.460 | As well, we have a Patreon account.

01:38:15.240 | It's patreon.com/andrewhuberman,

01:38:18.000 | and there you can support the podcast

01:38:19.700 | at any level you like.

01:38:21.440 | And today, as well as in previous episodes,

01:38:24.640 | I've mentioned various supplements.

01:38:26.380 | If you're interested in seeing what supplements I take

01:38:28.600 | and you want to explore for some other supplements as well,

01:38:31.600 | you can go to Thorne, T-H-O-R-N-E.com/u,

01:38:36.600 | the letter U, /huberman.

01:38:38.940 | Thorne is a supplement company

01:38:41.340 | that we believe to have the highest stringency

01:38:43.800 | in terms of what they put in the various supplements

01:38:46.960 | that they make, and the amounts that they put

01:38:48.440 | are very accurate.

01:38:49.400 | They've partnered with the Mayo Clinic.

01:38:51.480 | They've partnered with all the major sports teams,

01:38:53.600 | and we've partnered with them because we believe

01:38:56.080 | in their levels of stringency and accuracy.

01:38:58.840 | If you go to thorne.com/u/huberman,

01:39:03.840 | you can see what I take,

01:39:04.800 | and you'll also get 20% off any of those supplements

01:39:07.400 | or any of the other supplements that Thorne makes.

01:39:10.240 | So that's where you can find out more about supplements

01:39:13.140 | and the ones that I take.

01:39:14.280 | And again, you get the 20% discount

01:39:16.320 | on any supplements that Thorne makes.

01:39:18.800 | And last but not least, thank you for being with us.

01:39:21.680 | I hope you learned a lot.

01:39:22.840 | I hope you explore some of the tools

01:39:25.380 | and that the mechanistic information

01:39:27.160 | that you learned today will serve you well.

01:39:28.940 | If you know anyone that's interested in this topic,

01:39:31.360 | or you think that someone could benefit from it,

01:39:33.440 | please suggest the podcast to them as well.

01:39:35.580 | And most of all, thank you for your interest in science.

01:39:38.400 | [upbeat music]

01:39:40.980 | (upbeat music)

How Our Hormones Control Our Hunger, Eating & Satiety

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