Andrew Huberman: My Exact Routine To Optimize Brain & Body, I Do All Of These Every Day! | The Diary Of A CEO Transcript

Andrew Huberman outlines his ten daily protocols for optimising brain and body health

Steven Bartlett interviews neuroscientist Andrew Huberman about his book Protocols: An Operating Manual for the Human Body.

Summary

Steven Bartlett interviews Andrew Huberman, neuroscientist and host of the Huberman Lab podcast, about his long-awaited book Protocols: An Operating Manual for the Human Body. Huberman walks through ten daily protocols he considers the highest-leverage interventions for mental health, physical health, and performance — all of which cost little or nothing to implement. The conversation covers the science of cortisol, light exposure, exercise, stress mitigation, sleep, nutrition, neuroplasticity, and supplementation. Huberman also speaks at length about his personal faith, describing prayer as one of the most transformative practices in his life, and connects the limits of neuroscience to his openness to the existence of God. The episode closes with a discussion of walking, glucose regulation, lymphatic clearance during sleep, and the role of meditation in brain health.

Key Takeaways

FULL TRANSCRIPT

The ten protocols and the cortisol curve

Steven Bartlett: Andrew Huberman, we've waited many, many years for this, and now it has arrived. This is your long-awaited book called Protocols: An Operating Manual for the Human Body. Inside this book, I counted roughly 50 different protocols split across seven different areas — sleep, exercise, stress control, nutrition, light, focus, motivation and learning, and personal growth. You've written ten of the protocols you want to focus on sharing today. Can I ask why you chose those ten?

Andrew Huberman: They're the ones that are going to move the needle the most in terms of one's mental health, physical health, and performance. Your life will be so much better if you do them.

Steven Bartlett: And do they cost a lot of money to do the ten that you've picked?

Andrew Huberman: No. They could be done either at completely zero cost or on an existing budget.

Steven Bartlett: And do you do these ten things every day?

Andrew Huberman: Every day. There's one on there that I don't do every single day — I take off one day per week — but every single day without fail.

Steven Bartlett: And when you wrote them, did you write them in order of sequencing?

Andrew Huberman: Yeah, throughout the day, from start to finish, because this is the other thing: protocols synergize. They ratchet together. How well you slept last night is dictating how well you feel now. These are gears in a larger system. One moves, the other ones move. And while there is a place for pharmacology and supplements and things that you take, ultimately these gears fit together based on what you do.

Steven Bartlett: Okay. So let's get into it. What was the first thing that you drew? Because I saw there was a picture there.

Andrew Huberman: Okay, so in my inelegant drawing — I am a biologist, so we're allowed to do this — this is essentially a plot of where you wake up in the morning and then where you go to sleep at night. These are not hours of the day. These are the different protocols: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

This line represents the healthy cortisol curve. Most people don't realise that you wake up because of a rise in cortisol. It's literally called the cortisol awakening response. If you've ever woken up one minute before your alarm clock, it's because the cortisol awakening response is heavily entrainable — meaning it can be matched to external stimuli. You want this peak in cortisol as high as possible in the first 60 minutes of your day.

Everyone thinks you want low cortisol, but here's the deal. High cortisol in the early part of your day is what provides elevated mood, focus, attention, and your ability to learn. It's also what establishes low cortisol in the afternoon and at night, which is a requirement for falling and staying asleep. So this peak sets up this trough. You want high morning cortisol and low nighttime cortisol.

These represent melatonin, the hormone of sleepiness. As we know, if you slept the night before, melatonin is essentially low in the morning. And the dashed line is adenosine, which is a downstream product of the use of ATP in your cells. The more you're awake, the more activities you do, the more you think, adenosine builds up. That's why you get sleepy.

What's very interesting is that when you spike your morning cortisol — and I'll explain how to do that in a moment — and you do that within the first hours of your day, you also establish a case where these little blips are stress, stressful texts, stressful events, but they're brief. We always hear that cortisol is bad, but our ability to have big inflections in cortisol, stress out, and then come back down to normal is very, very good.

If this peak is high, great. If this peak is not as high — if this is a medium or flat curve, what they call a flattening of the cortisol curve — you see shorter lifespan, less recovery from every kind of illness, and these stress bouts last a very long time because they're riding on a higher baseline.

Steven Bartlett: So if your morning cortisol level is lower or flat, then if I get that stressful text during the day, it will be a longer cortisol spike?

Andrew Huberman: Bigger and longer. And not only that, but there's an indirect but very important interaction between cortisol and melatonin. Your sleepiness hormone doesn't come on and function as well, and so sleep gets very disrupted.

A lot of people think, "Oh, I don't want my morning cortisol high." And a lot of women in particular have been told, "Don't spike your cortisol — that's going to lead to excess visceral fat, moon face," etc. There's a condition called Cushing syndrome, which is a massive overproduction of cortisol. It's a very rare condition. Most people are not dealing with that. Most people's morning cortisol is too low and their afternoon and nighttime cortisol is too high.

Steven Bartlett: How do they know this? How do they test this?

Andrew Huberman: This healthy curve, as it's called, was measured through consistent blood draws around the 24-hour cycle. And then it's been looked at in response to everything from caffeine to cold plunges to exercise to sunlight.

Protocol one: hydrate

So protocol number one is hydrate. Your mind is exceedingly more sharp when you're well hydrated, and it actually helps boost your morning cortisol. There's a very interesting interaction between the bladder being emptied — usually after people wake up, they use the restroom, they urinate — and then hydrating. There's an ascending pathway along the vagus nerve that serves to wake up the brain, and part of that has to do with hydration first thing in the morning. You awake from bed to urinate in the middle of the night because of an arousal phenomenon of hydration and the bladder being full.

Steven Bartlett: When you say hydrate, do you mean electrolytes or just water?

Andrew Huberman: 16 to 32 ounces of good clean water is fine. If you want to add electrolytes, great.

Steven Bartlett: How much is that? Is that a cup?

Andrew Huberman: This is 16 ounces. Maybe 18 ounces. So like a big mug. You want to consume about 80 ounces of water throughout your day. It's a lot, but basically everything you want to do in the early part of the day, you want to do less of in the evening part of your day.

Protocol two: morning sunlight

The next thing — and this is really key, it could have gone first — is you want to view sunlight or 10,000 lux artificial light. I could spend three hours talking about this, but I'll keep it really brief.

When you view sunlight, there's this beautiful phenomenon. It activates these melanopsin intrinsically photosensitive ganglion cells — the major focus of my work for many, many years. They literally extend physical wires that we call axons into your hypothalamus. Your master circadian clock resides there. We call that your suprachiasmatic nucleus. And when you view low solar angle sunlight — sun low in the sky — there's an abundance of UV, but it's lower when the sun is low in the sky. You can actually look at the morning sun more easily than you can the overhead sun. Why? The morning sun looks more yellow, orange, or even some red tones compared to the overhead sky.

The light coming from the sky is the same, but the specific wavelengths of light coming from the sun when it's low in the sky are the optimal stimulus for these melanopsin intrinsically photosensitive cells that tell your central clock it's time to wake up. The day is beginning.

There's also something incredible that happens if you get bright light in your eyes in that first — ideally 30 minutes, but even 60 minutes — of your day. There are two pathways by which your brain's circadian clock wakes you up. One is it sends signals through peptides it releases and neural signals. But it's also able to activate what we call the HPA axis — hypothalamus, pituitary gland, which sort of hangs outside the brain, and then adrenals. You release adrenaline. There's a unique window that passes after about an hour following waking where your suprachiasmatic clock can trigger an alternate pathway that literally goes down your spinal column and triggers your adrenals to release additional cortisol.

Viewing sunlight in the first hour of your day takes this peak and raises it. Here's what it would look like if you didn't view bright light in the first hour of your day — it would be here, which is bad. And your stress responses then would be bigger and longer.

Now, when I say sunlight, people say — especially in the UK — "There's no sun where I live." Okay, this could easily say daylight. Why? Because there's always daylight out. If you look at how bright it is on an overcast day in the middle of December, even in the UK at 8:00 a.m., versus midnight the night before, it's different. On overcast skies, less of the long wavelength light — the oranges and reds — are coming through. But you want daylight in your eyes in the first hours of your day. Go out on your balcony if that's all you can do. If you're in a car, roll down the window. It's not good to try and do this through a window or windshield.

There's so much data showing that spiking your morning cortisol this way establishes low cortisol and high sleepiness hormones at night, which is great. It buffers stress, and moreover kickstarts your immune system to protect you against bacteria and viruses you can encounter during the day. It is great for your metabolism, mood, ability to learn, and on and on.

If you don't have access to sunlight or daylight, using a 10,000 lux artificial light can be very beneficial. These 10,000 lux lights have been shown to significantly offset the symptoms of seasonal affective disorder. But what we're finding from this huge study from the UK Biobank is that you want bright days and you want dark nights, and they're additive. Having bright days is great for your mental health and physical health along a huge number of parameters. But having dark nights — even if you were in dim light all day — making it dark at night makes people healthier. The risk of dying early if you have bright nights goes up immensely. And we don't talk about this enough.

If you don't have access to enough daylight — like you wake up before the sun comes out and you're up for two hours before the sun comes out — I highly recommend getting a 10,000 lux artificial light.

Steven Bartlett: And last time we spoke, you took me outside after the conversation and you had an app on your phone — a light meter.

Andrew Huberman: I have no relation to the app, but I use it. It's able to tell you how much lux of light you're getting at the moment. But it's additive. So one thing that's important to note is let's say you miss a day — the next day, get outside for twice as long.

How long should you do it on a very clear morning with the sun rising? And by the way, you don't need to see the sun cross the horizon. You can just wait till it's elevated but still low in the sky. People who are concerned about UV damage should know that when the sun is low in the sky, the UV index is much lower. There's a phenomenon called Rayleigh scattering. Sunrises and sunsets are very beautiful and colorful. When the sun's overhead, it's hard to look at — it's this big ball of light, so bright because you're getting all the wavelengths, the UV all the way out to the infrared, coming at you in more or less equal intensities. When the sun is low in the sky, the UV is not completely scattered, but not as much of it is reaching your eyes. Much lower risk of sunburn, much lower risk of eye damage.

Here's the diabolical thing. Your screens are not nearly bright enough to kickstart this increase in cortisol in the morning, but they are very capable of increasing your cortisol levels at night, because the low level of cortisol at night makes you vulnerable to big increases in cortisol.

Steven Bartlett: Is it just exposing my eyes to the light, or does my body need to be exposed to it?

Andrew Huberman: Great point. And one of the protocols in there — it's not one of the ten I listed — is about the importance of getting sunlight on as much of your skin as possible as is socially appropriate. There's beautiful work from Glen Jeffrey's lab at University College London. They do a glucose tolerance test. They fast people, have them drink a glucose drink, and measure how fast blood sugar rises. And if they shine red light — long wavelength light — on people's backs and do the glucose tolerance test, they observe a more than 25% reduction in the peak. They also look at the rate of rise of blood glucose. It's buffering blood glucose rise, which we know is a good thing.

Steven Bartlett: Just to summarise — they shine red light on someone's back while they have a glucose shot, and their glucose spike is lower?

Andrew Huberman: That's right. And you can do this onto bare skin or through a t-shirt. Turns out these people's metabolism rose significantly. Why? Well, long wavelength light can actually go into and through your body. It gets absorbed and can go about 8 centimetres into the body. Red light and infrared can pass all the way through the body. And along the way it makes conformational changes in the way that your mitochondria handle electrons. This long wavelength infrared light that comes from the sun — it's the heat that you feel from the sun or from a long wavelength light device — actually allows your mitochondria to function more effectively, more efficiently.

Now, it's not to say that short wavelength light — blues, greens, and ultraviolet — are bad. We need ultraviolet light. We need it on our skin to make vitamin D. What you want is full spectrum balanced light, but not so much UV that you get a sunburn. And you don't want a lot of short wavelength light in the absence of long wavelength light. The best way to do that is sunlight in the early and later part of the day when the UV index is low. You're getting the full spectrum.

Indoor LED lights — like this — which we all spend a lot of time under, there's now evidence from Glen Jeffrey's lab and others that they may actually damage the mitochondria. We talked about melatonin coming from the pineal gland that makes you sleepy at night. You also have melatonin in most all of the cells of your body, and there it doesn't make you sleepy — it serves as an antioxidant. But it's sort of captured, and the way to liberate it is through long wavelength light. So you have a protective mechanism that's kicked on with long wavelength light that protects you against the oxidative stress and damage to cells.

Glen Jeffrey's lab has done experiments where they literally take a light like this and have people look at it for one to three minutes a couple of times a week. They look at people of different ages and different eye conditions. He's a serious vision scientist — he's not a biohacker, he has no interest in commercial products. People over 40 who experience age-related vision loss — we all do a little bit — experience improvements in vision when they do this simple thing. And why would that be? Well, it turns out that your photoreceptors, which absorb light and convert it into electrical signals that allow you to see, are the most mitochondria-rich and metabolically active cells in your entire body. They have a ton of mitochondria, and they need to protect themselves against the oxidative damage that comes with generating a bunch of downstream products from ATP. So long wavelength light is what protects us in this. You can see significant improvements in vision for people that view long wavelength light a couple of times a week. But only in people older than 40. And get this — only in people that do that in the first three hours of their day.

Steven Bartlett: What?

Andrew Huberman: Yes. Your eyes and your body and brain are not the same in the first third of your day versus the middle third versus the last third and at night. They're not. Your sensitivity to bright light causing bad effects after sundown increases — not immediately, but gradually. Your need for bright light in your eyes in the early part of the day is immense.

You asked whether light to other parts of the body works. Not for setting this system in motion, but it's a great idea to get out two to three times per week when the UV index is low — you can just look on your phone for the UV index — and in general be out in the early or later half of your day when the UV index is lower, and get some light onto your skin. You don't have to be naked or in a swimsuit. Great if you are and that's appropriate, but you can also just wear a t-shirt because the long wavelength light will go all the way through.

Glen Jeffrey and Roger Seheult — he's a physician who talks about the immense benefits of getting sunlight onto the skin for getting over disease, for enhancing immune system function, and on and on.

Steven Bartlett: Can you — because there's going to be a lot of people right now that are going to go buy a red light lamp.

Andrew Huberman: Not necessary. Sunlight. Think Pink Floyd — pass sunlight through a prism, it bends the light and you see the rainbow: red, orange, yellow, green, blue, indigo, violet. But also in that sunlight is ultraviolet light. Some UVB exposure each day to the skin increases testosterone and estrogen in both women and men and is important for libido. It actually reinforces romantic relationships for reasons other than sexual interactions — attractiveness, etc. Strong effects. So sunlight has it all.

What you don't want is to go outside when there's so much UV that you get a sunburn. And you don't want to think that red light is the only light you need. You want that warmth from the sun. And it gets better — when you go outside and there's a lot of greenery, greenery reflects long wavelength red and infrared light. Throw on some infrared goggles — you're not going to do this, but if you look, all that stuff would be glowing white in those goggles. Greenery reflects infrared light. How do you know it reflects light? Where's the coolest place to be on a hot day? Under a tree. Why? Because it's reflecting the heat, the infrared light. But when you're out in greenery, you're getting all that long wavelength light, and it bounces around and goes through you.

So get out into nature, walk outside. If you work and live in a city, get outside. Take off a brimmed hat because you do want the sun getting down onto your face. People are so terrified about accelerating aging based on UV, but we're not talking about baking yourself in UV light all day. The health benefits of this are immense. There's a Swedish study that actually showed that the more sunlight people got, the longer they lived. In fact, smokers who got a lot of sunlight — this isn't my favorite study, but we have to admit it's there — lived longer than non-smokers who didn't get enough sunlight. Don't smoke, but get sunlight.

Steven Bartlett: There'll be a lot of night shift workers listening.

Andrew Huberman: I have a section specifically for night shift workers, because here are the two scariest things: night shift workers live shorter lives, cancer rates go up, they're metabolically unhealthy, and it's very hard to mitigate. But I provide some tools specifically for night shift workers and for jet lag, because people travel.

Here's the really scary thing. You and I qualify as night shift workers, because the studies on night shift work — barring some of the more extreme ones — most of them were on how many people after 6:00 p.m. are on devices getting artificial LED exposure, or doing activities besides eating and socialising with their family or being in bed. If you work at night at home, you're still a night shift worker. You don't have to work all night to be a night shift worker. So we have a generation of kids that are metabolically sick.

Protocol six: evening sunlight

I'm going to skip to number six. As the sun is going down, you don't have to watch the sunset — that would be cool — but try and get some daylight in your eyes in the late afternoon or evening. If you're going to be working indoors from after lunch until nightfall, try and get near a window. Do your best. Go out on a balcony, take a quick walk around the building. Get some sunlight in your eyes without sunglasses.

When you get some sunlight in your eyes in the late part of your day — let's just say in the last third of your day, and the clock times don't matter here because we all get up and go to sleep at different times — you buffer those cells in your eye against the negative effects of artificial light at night. This is your Netflix inoculation, as I call it. You can be on your computer at 9 or 10 at night without it damaging your melatonin levels quite as much, without it disrupting your blood glucose levels and your sleep, if you get some bright light in your eyes in the later part of your day.

But there's one population of people for whom this doesn't work, and it seems to be adolescents. You can't buffer them against the negative effects of screen light at night. What happens if you use screen light at night? You get big bumps in cortisol. And people say, "Well, I can fall asleep just fine after being on my iPad or screen." True, some people don't have as much of a negative effect from blue light at night. But the blood glucose effects and the next morning cortisol effects are the problem. Remember I said high cortisol sets you up for low cortisol. Low cortisol sets you up for high cortisol. So you've got a population of kids whose cortisol is slightly but significantly higher in the evening and at night because they're on devices, and the next morning their cortisol levels are struggling to get up.

Steven Bartlett: You know, this is a tough one because teens socialise that way and you don't want to take their phones away. They cling to their iPads like my new bulldog Strummer clings to a chew toy — you can take it away from them, but they hate you for it.

Andrew Huberman: So I said view daylight, because you can't always see the sun, but even if it's overcast, just get out for a few minutes and take a walk. Your sleep will be better.

Protocol three: exercise

So we said hydrate, sunlight. And then number three — I know everyone's heard it — but if you can exercise in the first three to four hours of your day, you could do it in the afternoon without problem, but there's a huge advantage to doing cardiovascular or resistance training in the first three hours of your day.

In the book, I devote an entire chapter — chapter two — to exercise. And I explain what I think personally is the best way to structure an exercise program for somebody who doesn't want to be the most jacked, but wants muscle and definition and strength. Somebody that doesn't need to run a marathon for a record time, but wants endurance. Somebody who wants to be able to sprint reasonably fast and has middle distance ability too.

It's basically structured as follows: you either lift or do cardio on alternating days, three days total of lifting. Warm up reasonably, low volume of work sets — two to three work sets per exercise — emphasising compound movements. So not a preacher curl or a tricep kickback. Those are fine, but you're going to get a lot more bang for your buck if you're doing pull-ups, rows, dips — multiple muscles at once, multiple joints moving at once. Some hip hinge movement — could be squat, hack squat, some deadlifts. And I talk about how to get specific aesthetic effects in there too. I mean, I'm by no means an exercise physiologist, but I've been resistance training since I was 16. I'm now 50 — I'll be 51 in a month — and I feel great.

Cardio at the start if you're doing resistance training, or not at all. I warm up for five minutes of cardio and then resistance train, but I do the cardio on alternate days. Three days total of cardio. One day of cardio is long and slow for about an hour. One is about 30 minutes at moderate intensity. One is a short one — like I did this morning. Jumped on the air bike, pedal easy for a minute, then go all out for 30 seconds, easy for 10, 30, 10, 30, 10, 30, 10, and then you're off the bike. Basically max heart rate training. And the day after leg day, if you do your legs right, take a rest day.

Here's the interesting thing about exercise. You notice I didn't say deliberate cold exposure. You want to blow some minds? I will go toe-to-toe with anybody on the internet or off the internet. Deliberate cold exposure does not raise cortisol significantly. It's amazing to me that the same people suggesting moderate to high-intensity exercise are saying that deliberate cold exposure raises cortisol. It's simply not true. Not true for women either — a lot of people said, "Is your book going to be for women and men?" I distinguish between data when there are data showing that it's different for women and men. I acknowledge when there's no data in women. And the data are very clear in women and men: trivial increases in cortisol, but magnificent, huge increases in adrenaline, norepinephrine, and dopamine from deliberate cold exposure. And those so-called catecholamines are great to have rolling into your day. They're the things of alertness and focus. The appropriate stressor for cortisol — appropriate meaning the one that you want — is a psychological stressor. Working out with weights for 45 minutes, taking your sets near to failure, going for a run for 30 minutes.

So the point being, if you do this exercise in the first three hours of your day, you're getting a big inflection in cortisol. Again, this is what you want. Now, some people can't exercise first thing in the day — they either don't want to or they can't by way of schedule. And if you go into exercise in the later part of your day, that's fine. Your cortisol will come back down. You can do some long exhale breathing to slow your heart rate. Andy Galpin talks about that. Take a hot shower, which paradoxically lowers your core body temperature and then helps you sleep. When you heat up the surface of your body, you have a thermostat in your brain called the medial preoptic area, and it goes, "Oh, the surface of my body is warm. I should probably cool my core body temperature down." And you fall asleep better. This is like the putting-socks-on effect or the hot bath effect.

Steven Bartlett: I assume a massage or something like that also?

Andrew Huberman: Great. You have access to that in the last hour of your day. My fiancée used to be a masseuse for many years, so —

Steven Bartlett: Awesome.

Andrew Huberman: So when you exercise for a few days early in the first three hours of your day — let's say you do that two times — the next morning you wake up feeling a little bit more willing to exercise. Did your willpower change? Well, in some sense, yes. But what happened was your cortisol entrainment mechanisms changed. Your suprachiasmatic nucleus all day is clocking what you're doing. Let's say you eat at 9, 12, snack at 3 and 6:30. You have a food anticipatory signal. Ghrelin is secreted, makes you hungry. We are clocks, and the synchronisation of those clocks is very, very important. When you exercise at roughly the same time of day, early in the day, you will have more energy to exercise. In the first 15 minutes before that, you'll notice you kind of start stirring around. Yes, part of it is cognitive, but a lot of it actually is your brain anticipating that exercise is coming.

The anterior mid-cingulate cortex and tenacity

Steven Bartlett: You reminded me of something that I saw you talk about, which was the anterior mid-cingulate cortex. And I think you described this as being one of the most interesting discoveries of neuroscience.

Andrew Huberman: The anterior mid-cingulate cortex — it's not directly exposed here, but it would sit somewhere like there. This is an amazing structure. When we feel some sort of pressure — social pressure, physical pressure — that we hate, and we decide, "I'm going to lean into this, I'm going to compete, I'm going to push through this internal or external resistance," neurons in the anterior mid-cingulate cortex are just firing away. And if that area is stimulated — my colleague Joe Parvizi at Stanford showed this, he's a neurosurgeon — people say, "I feel like a challenge is coming on and I'm going to lean into it." This is the brain area of tenacity.

The amazing thing is it has connections all over the brain with reward systems, etc. So it's collecting information about when it gets activated, what's going on in the world that makes you feel pressure, when you feel like pushing back, when you don't. But the best part is it is highly subject to plasticity. People who diet successfully — their anterior mid-cingulate cortex gets bigger and more active. People who embark on a new exercise program, adding some component of exercise — for me it's mobility work because I've got a little stiff over the years. When you do something that you don't want to do, that you don't reflexively do, your anterior mid-cingulate cortex gets bigger and more willing to engage in challenging things going forward.

Steven Bartlett: So that's the key point — it sets you up to be able to do more challenging things in the future.

Andrew Huberman: That's right. Why would you do deliberate cold exposure? I'll tell you why. Because your ability to sit calmly — or even not so calmly — when your system is flooded with adrenaline and norepinephrine, and to be able to trigger that with cold water safely, like a cold shower or getting into a cold ice bath — it's safe as long as it's not so cold that you're hyperventilating beforehand on purpose — that carries over to your ability to keep your head straight when other things trigger adrenaline. You don't get ten stress systems. You get one.

So I came up with a model for arousal. People hear arousal and they think, "Oh, it's got to be romantic arousal." It can be, but arousal is really just how alert or sleepy you are. You can be really sleepy, like in a coma, or you can be in full-blown panic. Nobody wants that. But a seesaw is the right analogy here, because we have this thing called the autonomic nervous system. The autonomic nervous system is made up of two parts: parasympathetic and sympathetic. They're in different parts of the body. They both connect to most every organ. But in general, when you are relaxed, that's what we call the reflection of parasympathetic tone going up. When you're stressed, it's the reflection of sympathetic tone going up.

The ability to navigate stress of all kinds depends on your ability to control the tightness of this hinge. When you train your ability to think, breathe, and stay calm when your system is flooded with adrenaline, and that happens later in a way that was non-voluntary — something happened that you didn't want to happen — your brain immediately flits to the understanding of that place and you are able to maintain thoughtfulness. You can know not to speak. That's often the best thing you can do. You know to react or not react.

In fact, when you get into a cold plunge, one of the beautiful things about cold is that your prefrontal cortex — involved in strategy setting and making meaning out of what's going on — its activity is greatly suppressed for the first 20 to 30 seconds. Know this about every stressful circumstance: in the first 20 to 30 seconds, you are brain damaged. You are in that mode where you could react physically. Sometimes that can save your life, but most times you just don't want to do anything. Step out of the way of the car, get away from the aggressor, whatever. But most times you're best off not saying a darn thing. And then your prefrontal cortex slowly starts coming back online.

Steven Bartlett: This is good relationship advice.

Andrew Huberman: Very good relationship advice. I wish I had learned it long ago. Actually, last night I looked on Twitter and I saw something that was both perplexing and a little bit upsetting to me. And I went to sleep knowing how to deal with it — some long exhale breathing. But I woke up this morning and it turned out to be a complete misunderstanding and everything was reversed. But last night I thought about sending a text, and I thought, later at night the prefrontal cortex is already diminished. This is why stress feels so much harder to deal with at night.

Steven Bartlett: And prefrontal cortex — we should describe that. Logic and stuff.

Andrew Huberman: So the frontal cortex — you have the frontal and motor areas here. And your prefrontal cortex is basically a big patch of real estate behind your forehead that in humans is greatly expanded compared to in other mammals. They have less prefrontal cortex, so they're more driven by their impulses. One of the most incredible things that every child and adult needs to develop is what's called top-down inhibition. You feel an impulse, but you resist the impulse.

In fact, the way I've mostly trained my dog Strummer — because it works — is I taught him at nine weeks of age: put down a piece of food, of course he goes for it, he loves food, and you teach him "wait." And he sits there. And you teach him to look at you. And now I can have him moving toward a piece of food and I say "wait" and his nose can be this far from it and he'll just stop. He has great top-down inhibition. Is it about food? No. Am I trying to torture him? Of course not. It's so that if I say "wait," he can suppress his arousal.

This is one of the most valuable skills. People with frontal damage show an inability to do that, which is why sometimes they're violent or they say inappropriate things. People who are tired, stressed, drunk — prefrontal cortex activity is suppressed. Get in a cold shower. First 20, 30 seconds, it's kind of fun. You're like, "Here I am with less of a brain than I had getting in." And then 30 seconds later you're like, "I can do this."

Steven Bartlett: This explains why you do things tired.

Andrew Huberman: Don't do things tired. Don't say things tired. Impulse control is way worse.

Steven Bartlett: When I heard you talk about the anterior mid-cingulate cortex and that there was this part of the brain that was kind of like the willpower — you described it as the tenacity muscle — it completely changed my relationship with hard things. Because it made me realise at some conceptual level that every hard thing I overcome is better equipping me — like when I curl weights in the gym — to do harder things tomorrow. When I heard there's a neurological investment I'm making in my future, and then you talked about doing voluntary difficult things like the cold plunge —

Andrew Huberman: Or learning a new language. It can be cognitive in nature. It can be learning to dance if that's stressful for you. Anything that creates some resistance for you, internal resistance. This is a beautiful structure because it's wired into cognitive capacities and our ability to build them, and into challenges with emotional challenges.

Steven Bartlett: We're kind of optimising our lives towards comfort though, aren't we? That's like a winning formula — more comfortable things.

Andrew Huberman: I think Jack Dorsey said it best. There's this great video of him online, a small lecture he was giving, where he said anytime we exchange ourselves — our money, our time — for convenience, we are almost always giving up something that's fundamentally useful for us neurologically. And it's okay to do. I order food on DoorDash because there's great food and I don't have a lot of time to cook. I'd like to devote my time to other things. I'm trading for convenience. But if you're aware of the trade-off, you're much better off. And the real question is what you're going to do with that additional time.

While I'm against overoptimisation to the point that it pulls you out of life and diminishes it, I am all for striving and optimisation in ways that allow you to lean into the rest of your life with more vigour. I think Arthur Brooks says it best. We are wired, and meaning comes from striving. And within striving is some struggle, and within struggle is also the release from struggle, and that's also very satisfying.

Here's the overoptimisation thing to me in a nutshell: there are people for whom doing two of the things I described for five minutes each per day will experience a significant improvement in their mental and physical health. There are people who are sort of like junkyard dogs — they can live on anything, they have a ton of vigour. But everyone can afford to take a look at what they're doing now and try and move the needle toward more vigour, well-being, happiness, and peace by doing certain things.

Nutrition

Andrew Huberman: I talk about nutrition in there, and I really go into the literature so people can choose. But if you look at what most people could benefit from doing — and you could do this with vegan or vegetarian, it's a little harder — the best diet is going to be the following. Not too many calories, not too few — that's individual, you can calculate that. But you need to get what I call high complete protein-to-calorie ratio proteins. This is a concept I came up with because if you look at the literature, yes, we need the essential amino acids — that's a complete protein — but you can get that from beans and rice. However, to get 30 grams of complete protein from beans and rice, you're going to consume about four to five times as many calories as is required if you get it from a chicken breast.

So you want to eat some high complete protein-to-calorie ratio protein. Eggs, lean meat, fish. And then everyone knows you need fibre — vegetables and fruits. But what I will say is that many people who remove starches entirely, or remove vegetables entirely, will find that their autoimmune issues resolve, and there are reasons for that. We have to acknowledge that. But most people should be eating some vegetables and fruit for micronutrients and fibre.

Low sugar fermented food — very clear from Justin Sonnenburg's work from Stanford — very clearly lowers the inflammatome. In fact, when they had people eat more fibre, for many people inflammatory markers went up. No one likes to talk about that, especially not the vegans. But too much fibre can be noxious for some people and pro-inflammatory. So low sugar fermented foods like sauerkraut, kimchi, beet kvass — delicious. Problem is they tend to be expensive, but you can make your own and there are recipes online.

I don't want to get into the seed oil debate. Just use olive oil. It's delicious. It's relatively inexpensive nowadays to get real olive oil. Small amounts of butter. Why are we even debating seed oils? It's so dumb. The seed oil debate is like the fastest way to kill neurons that I'm aware of. The studies are not well done. You're comparing a processed food diet that includes seed oils versus clean seed oils versus a high meat diet with processed meat. It's a mess. As a scientist, you just look at this and go, this field needs some really good studies. 90% of them — you don't even have to be trained in nutrition to see there are five different variables here and four over here. This is what you would call a bad experiment.

Olive oil — the data are great. It's impressive. And then starches are great for fuelling muscles and glycogen and brain, but you don't want to overdo them. And the way that people tend to overdo starches is by eating starches combined with a lot of fats. Sourdough bread is great. Sourdough bread with butter is even better if you ask me. Sourdough bread with equal amounts of butter and bread — you're starting to get into problems. It's very hard for people to overeat starches unless they have a lot of fats with them or sugar with them.

Steven Bartlett: On starches — is there an impact on sleep with what you eat late at night?

Andrew Huberman: Many people who don't eat enough starches find that they have sleep issues. And there are reasons for this. We talk about comfort foods — typically people think junk foods when they think comfort foods, but foods that increase glucose lower cortisol. Starches lower cortisol. And you want your cortisol low at night. Helps you fall and stay asleep. Now, you don't want to eat too close to bedtime. You also don't want to have gnawing hunger at bedtime.

But here's the interesting thing. What is cortisol? Is it a stress hormone? No. It's a hormone that's released during stress. But cortisol's job is not to deal with stress. Cortisol's job is to mobilise energy in the body. When cortisol goes up, glucose is mobilised and other fuels too. So when you eat starches, you buffer cortisol. There's a very clear relationship here.

People who are not eating enough starches, who then allow themselves that bowl of rice or a bowl of pasta in their final meal of the day, or a little bit at lunch and at dinner, maybe even a bowl of oatmeal at breakfast — they feel more even psychologically. They have more physical energy. Sometimes people with chronic stress issues notice they stop shaking. People with autoimmune issues sometimes resolve those, because your cortisol is buffered. Because your blood glucose is elevated, your body isn't tapping into the survival system to try and mobilise glucose.

Cortisol, phones, and morning stress

Steven Bartlett: I have this outstanding question that I have to ask you. It goes back to the picture that you drew of the graph. You said high cortisol in the morning is a good thing. So what if I pick up my phone first thing in the morning and I look at my worst emails? In some sense, from the perspective of spiking your cortisol — is it a good thing? Can you do it outside while getting sunlight? I was wondering if it matters how the cortisol comes, because what if I stress myself out in the morning?

Andrew Huberman: It doesn't matter from the cortisol perspective. The problem is the rumination that comes with stress. The nice thing about physical stressors that we control — like a workout or a cold plunge — is that they have an onset and an offset. Yes, they start faster than they end. You have stress and it kind of carries over. You ruminate. But psychological stressors tend to bang around in our brain a lot, and late at night, and they tend to come back.

I will say this: I think 2027 is going to be the year that we close the coffin on this "cortisol is bad" thing.

Steven Bartlett: So how should I think about cortisol? Because right now I think of it as the stress hormone.

Andrew Huberman: It's to mobilise energy. So you can use it. And if you're going to sleep at night, you don't need to mobilise energy, so you can rest and reset your body. Cortisol is an energy-promoting hormone. So if I walk up on stage and there's a big audience, my cortisol level is going to go up. If you're stressed about it, maybe a little bit more, but it's a preparation hormone. You're preparing for adversity, but also great things.

There are these beautiful studies from a guy named James McGaugh and Larry Cahill, which showed that if you want somebody to learn something, you know what you do? You spike their cortisol before, during, or after that thing. Why not? Trauma does that and you never forget. All you do is work on trying to remove the emotional load of that traumatic thing.

Steven Bartlett: Wait — does that mean that someone who's listening to this podcast right now in the gym is going to have better knowledge recall of what we talked about than someone who's listening in bed?

Andrew Huberman: Great question. So I have a chapter that's all about learning, motivation, and plasticity. We've all heard exercise makes your brain better. How? Why? Turns out it's very important to understand. There are two ways it does it, or at least two. One is it raises your levels of arousal. Exercise doesn't make you smarter. Exercise makes you more alert coming out of the exercise so you can go learn things, because it turns out you have to be alert to learn things. In particular, you need adrenaline and cortisol elevated to learn things.

So when people say weightlifting is good for your brain, cardio is good for your brain — turns out long slow cardio, my endurance friends aren't going to like this, is not that great for your brain. It's not bad for your brain, but it's not that great. Turns out an intense weightlifting session or high-intensity interval training session — in the four hours after that, you are primed for learning. Why? You've got a lot of stimulatory molecules in your body and you can focus better.

Steven Bartlett: What about if I'm a podcaster and I want to be able to ask good questions and use my mouth and my brain — not necessarily just learning but performance of my cognition?

Andrew Huberman: So the performance curve is basically an inverted U. If you're not alert enough, you can't do what you need to do. If you're too alert, you can't do what you need to do or learn. So you want to be at the top of that inverted U. And a lot of what learning is about, and a lot of what the mid-cingulate cortex is about, is getting from "I don't want to do it" up to the top of that U. Then it's usually about not getting too stressed.

Protocol five: the physiological sigh

Now I learned the best trick for this — the two best tricks. And in fact, that will take us to number five. You can use it any time of day, which is: use physiological sighs to reduce stress fast.

I have a chapter on stress mitigation and it's got essentially two components. One is how to limit stress in the moment. Very, very important to know how to limit stress in the moment.

Steven Bartlett: Why is it so important?

Andrew Huberman: Because meditation, a great night's sleep, massage, social relations, being well-fed and hydrated — all of that helps you buffer stress. But when something happens and your heart rate is too high or you're shaking and you can't organise your thoughts in the way you want, none of that helps. You've gone over the line. You're too far on the arousal spectrum towards alert.

It was about 2016 that I realised I'm going to take a significant portion of my lab and work on this problem. I want to find real-time tools for mitigating stress. So I started hanging around with people from special operations who spend a lot of time in cold water during their training. And I started talking to people in performance fields — in particular neurosurgeons, people who deal with life or death circumstances for many, many years and maintain immense calm.

One of my closest childhood friends — you should have him on this podcast. His name is Dr. Eddie Chang and he's a neurosurgeon at UCSF. He's the chair of neurosurgery and he's brought people out of locked-in syndrome to speak through AI. He's also a bioengineer. He's also been my friend since we were seven years old. And we talk three times a week these days about science. I actually visited his laboratory and got to see him take a golf ball-sized tumour out of a guy's forebrain while the guy was awake. Eddie is the calmest guy you'll ever meet. Why? Because a movement of less than a millimetre in the wrong direction for him could cost a patient's life.

People have ways to calm down in real time. So I teamed up with a colleague — his name is David Spiegel. He was at that time our associate chair of psychiatry and he studies hypnosis — clinical hypnosis for smoking cessation, pain management, and anxiety. And I should say mainly Malise Yilz Balban in my lab did the study. She built this stress lab with VR and stress. And then we did this study where about a hundred or so subjects were fitted with trackers that measured heart rate, heart rate variability, and sleep. People were in one of four groups. They either meditated for five minutes a day, or they did box breathing — inhale, hold, exhale, hold for five minutes. Or they did cyclic hyperventilation — some people call this Wim Hof breathing, tummo breathing, pranayama breathing. It's big inhales, passive exhales, repeated for five minutes. That massively spikes adrenaline, which isn't a bad thing — you're controlling it anyway. Does not spike cortisol very much, incidentally. And when you do those exhales, you're blowing off a lot of carbon dioxide, so it shifts your internal state and tends to make people very alert.

Or they did a fourth condition where they did a double inhale, long exhale, repeat — the so-called physiological sigh. Jack Feldman at UCLA and some other folks in the 1930s had observed that animals and people, when they're very relaxed, would do this kind of strange pattern of breathing where they would go — a double inhale, long exhale.

Jack's lab discovers there's a brain area called the parafacial nucleus, which is specifically there to generate this double inhale-exhale pattern in animals and in humans. Nature doesn't make mistakes like that. It turns out there are two breathing centres. One is called the pre-Bötzinger complex — named after a bottle of wine — which generates the basic pattern of breathing where you inhale and exhale. This other structure, the parafacial nucleus, which we all have, is involved in anytime you double up the inhales or exhales. And it's involved in breathing while you speak, sing, or eat. And it generates these physiological sighs, which it turns out get triggered in environments where there's not enough oxygen, or when you get claustrophobic, or when you get very stressed. Carbon dioxide goes up, your brain senses that, and it triggers the gasp reflex.

That double inhale maximally inflates the hundreds of millions of little sacs in the lungs. And then when you exhale, you offload the greatest amount of carbon dioxide. If you just go — you're not offloading as much carbon dioxide. But if you do the second short inhale, it takes these little sacs in your lungs — which are like balloons at a kids' party that are empty but fluid-lined on the inside, so there's some surface tension inside them, they're sticking together — the double inhale opens those up, and then you offload the carbon dioxide.

Now, that's great. But the real magic of deliberate long exhales is that they slow your heart rate down through a process called respiratory sinus arrhythmia. This is like the most important thing for anyone interested in stress, exercise, sleep, and wellness. Because the wild thing is we have this vagus nerve. Everyone likes to talk about the vagus nerve. It's a massive nerve bundle that collects sensory information and chemical information from the organs of the body and sends it up to the brain. And it's classified as parasympathetic — calming. But you know what's funny? Neuroscientists, when they want to wake up a person during an experiment like a neurosurgery experiment, they stimulate the vagus. A treatment for depression is to stimulate the vagus. Guess what that does? It makes people more alert. So it's a mixed nerve.

But the really cool part about the vagus is that it's not all ascending. 85% of the information is going up from the body through the vagus. But there's another pathway that goes down — down to your heart — and it controls the slowing of the heart rate when you exhale. Heart rate variability is the slowing of your heart rate when you exhale. You want to increase your HRV? Do a few deliberate exhales during the day. People go, "How do I get my HRV up?" Well, yes, you do some VO2 max training, some max heart rate training, some HIIT workouts. But if you really want to increase your HRV in sleep and while waking, just do some deliberate exhales during the day, because that's the parasympathetic, the calming arm of the vagus pushing down on your heart rate.

All of the groups I described saw benefits, but it was the people who did these physiological sighs that benefited the most. So then I started exploring how fast heart rate slows down with physiological sighs. And it turns out you don't need to do it for five minutes. Do it once. You're feeling stressed. You're going on stage. You're waiting for a diagnosis. You feel too alert relative to how you want to feel for whatever reason, good or bad. You're about to get married. You just — one double inhale, long exhale until your lungs are empty — and it's immediate.

For me, that was immensely gratifying. Because it's fun to publish papers, but I was so gratified because I'm like, finally — if I didn't sleep well, or if something stressful happened even though I slept well, I can calm myself down like that.

Steven Bartlett: Real-time tools for stress are what we all need. The interesting thing is that you can also raise your stress threshold, and a lot of the stress mitigation chapter is also about how to do that. We need to train for discomfort so that the little things don't feel so big.

Andrew Huberman: This is also important in survival situations. You need to be able to think very clearly about what order of operations to take, what direction to escape through. This is not about setting yourself to tolerate more pain and abuse. This is about the exact opposite. This is about safety. This is about self-protection. And this is about noticing — when we're alert but calm — we can notice the subtle ripples in people around us.

Waking in the night and falling back asleep

Steven Bartlett: A lot of people wake up at like 2 or 3:00 a.m. in the morning, in the middle of the night, and they don't really know why. They don't know how to get back to sleep. They start worrying and ruminating.

Andrew Huberman: Very, very common. So they can use the physiological sigh as a tool in that moment — definitely ten long deliberate exhales. There's also this really crazy trick that I put in the book that has indirect scientific support. You want to hear it? Best way to fall back asleep.

To fall asleep or to fall back asleep, you need to stop thinking about your body position. It turns out there's a direct relationship — through a few steps, but there's a dedicated circuit — between your eyes, their movements, and your cerebellum, which is involved in proprioception and balance and a number of other things. Your cerebellum is involved in balance, in learning, and it's actually very important for generating and responding to the error signals between what you're trying to do and what you can do. That error signal turns out to be one of the most important things for generating learning. And your cerebellum is critical for that. It's also involved in timing.

So you need to kind of turn off your recognition of your own limbs to fall asleep. How do you do that? You know what works with babies? Walk back and forth at a particular pace — this was defined in a Japanese study — and have people swing the baby back and forth just gently. And the baby falls asleep. Parents figure out the exact cadence with a very small margin of error through trial and error. It's been looked at in the lab.

It turns out when you rock back and forth, your eyes move. This is a very, very ancient system that exists in all jawed animals, including us. As we move through space — walking, running, swimming — the world is gliding by, what we call optic flow. You would see the world blurry. But you have a compensatory eye movement that, unbeknownst to you, because of a connection between your eyes and these brain stem areas and your cerebellum, creates a visual slip error and your eyes automatically offset that error. So when I go like this, the world seems stable.

It turns out there's a pattern of eye movement that can shut down the proprioceptive circuits in the cerebellum, make you forget your limb position, and it greatly facilitates the speed at which you fall back asleep.

You're going to close your eyes. You're going to move your eyes slowly to one side underneath your eyelids, then to the other side. Then up, then down. Now you're going to move them counterclockwise in a circle, and then clockwise in a circle. And now, still with your eyes closed, you're going to kind of point them towards your nostrils — you're not going to cross your eyes — and you're going to do a long exhale.

That done two or three times generally has people waking up the next morning going, "What happened?" What happened is your proprioceptive circuits are shut down. That's kind of fun to do, and it costs nothing, and it generally works. Some people, if they're really, really stressed, it might not work. But this is what I do if I wake up in the middle of the night. I usually go to the bathroom, get back in bed, do long exhale breathing, and I do that, and I wake up the next morning. It really works well.

So well, in fact, that there's a company based on work done from two MIT scientists. They have a sleep mask that generates this pattern of eye movements through a little electrode behind the ear. It stimulates the extraocular muscles in just the right patterns. And I tried it and you fall right asleep. And it monitors REM directly — this is direct monitoring of REM, not through changes in heart rate and breathing. It's wild. And it can control your eye movements to induce more REM if you want more REM.

There will be a time very soon — within the next 12 to 14 months — when, because of devices like the one they and others are making, you're going to be able to say, "I want two hours of deep sleep, I want two hours of REM across a six-hour night because I can't afford to sleep my full ration of eight." And you will be generating those eye movements during sleep in order to facilitate — not force, but facilitate — those patterns of sleep.

Peptides, sleep, and GLPs

Steven Bartlett: Did I hear you say that there's a peptide that can help your REM sleep?

Andrew Huberman: Yes. I have no affiliation to it. It's called pinealon. I will tell you, in the book I do not talk about hormone therapies, peptides, or psychedelics. The book is about what I know for sure. Hormones, peptide therapies, and psychedelics are at the front edge right now. I'm very much involved in looking at the research, talking to the people that are doing these things. And yes, I dabble in these things. I'm an adult. I can do that.

So pinealon is very interesting because I found that if I took an itty bitty bit every third night — I tried this experiment for about a month — I got massive amounts of REM sleep that night, but also on subsequent nights. I hosted Dr. Abid Balwi on my podcast, who in my view is the most knowledgeable physician on the topic of peptides. He tells me that pinealon is potentially involved — there are some data supporting its use for encouraging pineal health. So the actual health of the pineal gland, which makes melatonin and does other things too. I think pinealon is a great tool to use sporadically. I don't use it regularly.

As long as we're talking about peptides — I am peptide curious. I'm from the Bay Area. I have not tried any GLPs yet, but I'm getting curious about very, very low dose tirzepatide or retatrutide.

Steven Bartlett: I'm peptide curious, but I'm scared. I'm scared because — you've got to inject most of them, right?

Andrew Huberman: It's a tiny little thing. Here's my opinion — it will be popular with some people, unpopular with others. Obviously, as with hormone therapies or anything else or supplements, like sleep, hydration, sunlight, exercise, nutrition — you need all that stuff. The behavioral tools are the foundation. Great things can happen when you build on a foundation. Things can happen when you build on a non-foundation, but it doesn't last long. But the combination of the two can be pretty awesome, especially if somebody has the means and the interest.

So the GLPs — the weight loss drugs. I think retatrutide is amazing. It's not just a GLP. It also hits the glucagon and GIP pathway. This is the one that Eli Lilly invested hundreds of millions of dollars into researching, and it went through phase three. People lost approximately one-third of their body weight in about a year or so.

Steven Bartlett: Is that a good thing for everybody?

Andrew Huberman: No. So what's happening is — the psychedelic community talked about microdosing, and that phrase has now been incorporated into GLPs. People realised they could bypass a lot of the side effects and the cost by microdosing GLPs. These are anecdotes, so I want to be clear, and I'm not pushing peptides or selling peptides.

I have a friend who's very, very sceptical about anything that's not fully FDA approved — "I don't want to hear about your biohacking nonsense," this kind of thing. But she has chronic fatigue syndrome. She's seen all these physicians — physicians at Stanford, physicians at UCSF. She's a very smart, nuanced person, but she has a wall there. She's started taking a very low, very low dose of tirzepatide once every ten days. And tirzepatide is one of the GLP drugs. It's not just increasing levels of glucagon-like peptide — it's also touching GIP and glucagon. It's not just suppressing hunger and appetite, but it also seems to lower inflammation.

Yes, there are concerns about vision loss in people who have certain structural abnormalities of the eye. Yes, there are concerns about apathy if people take too much of them. It seems to reduce alcohol craving for people that like alcohol, and sugar craving more generally. And it can reduce craving for everything if you take enough of it.

Keep in mind these drugs are ramping up levels of GLP a thousandfold or more. The body has never seen this level of glucagon-like peptide in the history of humans. And remember, this whole thing was discovered because a smart biologist was studying why Gila monsters — these reptiles — only have to eat a couple of times a year. It's because they make a peptide called exendin, which turns out to be homologous to glucagon-like peptide one in humans. The reason these reptiles don't have to eat very often is because they always feel satiated. Why? Because they have very high levels of glucagon-like peptide circulating. We don't. And it works through two mechanisms: it tells the brain mechanisms for satiety to ramp up their activity, so your brain is telling you it doesn't really want food, and it also makes people feel full, which is the basis of some of the side effects of nausea and other things.

So she will tell you, "Oh my god, my energy's back. My inflammation markers are way lower. I'm not cured, but I feel so much better." Very, very hard to dispute that kind of experience if you're the patient. We could talk about safety and sourcing, etc. But people are starting to realise they can microdose stuff, but you won't see randomised control trials that are going to push this kind of notion.

So then there are things like pinealon for sleep, epitalon perhaps for DNA repair — I haven't dabbled with that one yet. And then there are the so-called growth hormone secretagogues. So we're talking about tesamorelin, ipamorelin, CJC-1295. These will promote more growth hormone release in sleep. They will have a negative feedback effect where they're going to shut down some of your own production, and people get a bit leaner and they claim their deep sleep is better, and it can increase insulin sensitivity. I'll tell you, I've tried sermorelin. I've tried a few of these other ones. They nuke my REM sleep. They give me a ton of deep sleep. I don't like them. I've tried pinealon and I'll take it now and again.

And BPC is the one that gets everybody talking, because body protection compound 157 is made in the gut. People claim — and I do think their claims are accurate — that they feel as if their recovery from injury was accelerated. And I believe them because I've spent a lot of time with the animal data, whether it's an Achilles tendon transection or nerve regrowth or tendon or ligament regrowth and vascular. Yes, it does seem to accelerate healing across the board. But the concern is you could vascularise tumours. Would I take it? No, I don't have an injury right now. I don't have any reason to take it.

So I don't think people should ask, "Should I take peptides?" You should ask what effect in your life are you trying to achieve. And then maybe BPC makes sense. Maybe it doesn't. You're not going to find many clinical trials on it. It has a very, very high — maybe infinite — LD50, meaning no one has really figured out how much can kill you. But that's not a good way to run your life. And it's somewhere between a drug and a supplement.

Steven Bartlett: I think this is one of the concerns — one of the conversations I often hear around GLPs at the moment — is that they just haven't been around long enough for us to know the side effect profile over a long period of time. Is there any truth to that?

Andrew Huberman: Well, do you want to be in the experiment or out of it? Do you want to be in the control group or the experimental group? For somebody who has serious obesity issues, the tirzepatides and Ozempics and retatrutides could potentially save their life.

Vision loss is a serious consideration. And I'll just be direct — vision is my home. David Sinclair recently went on Rogan and said the amount of blindness caused by GLPs has doubled, which scared everybody.

Steven Bartlett: I heard that.

Andrew Huberman: But there's a structural abnormality in the eye of a subset of people for whom that's true. And it's a great idea to get your eyes scanned. So — as the model comes apart here — light obviously comes in. You've got that cornea on the outside of the eye and the lens focuses the light onto your retina, which is this pie crust-like structure that lines the back of your eyes. It's an amazing structure — three cell layers thick, catches light, absorbs light. The photoreceptors turn that into electricity through phototransduction. Then that electricity is cast forward to a set of cells that line the inner part of the retina that we call retinal ganglion cells. And then they send their wires — their so-called axons — out the optic nerve into your brain. They course along the bottom of the brain and they enter your brain, including your circadian clock. You get vision, you get sleep-wake rhythms, you get hormone regulation by light. It's just incredible.

Where they exit the eye is called the optic nerve head. And if the optic nerve head is a nicely shaped and sized tube for them to exit, great. Too big, that's not good. But too tight's not good either, because those wires get pinched off. This is part of what happens in the disease glaucoma — the eye pressure goes up and those axons die away. These cells die away and people lose vision. It's the second leading cause of blindness in the world.

So in some people who have a structural abnormality — a structural feature of the optic nerve head where these wires leave the eye — it does seem that the GLPs put them at greater risk for causing some cinching off of those cells, and there have been cases of blindness. But GLPs are not making many people go blind. Everyone should get this area of their eye imaged. You can go to your ophthalmologist or optometrist, ask for an eye pressure test. Usually insurance covers it, but definitely worth paying for.

Psychedelics, DMT, and the question of God

Steven Bartlett: You took DMT in a faraway land where it was very legal. And I actually did work in a psychedelics company for about a year. It was deeply, deeply fascinating. The reason I was compelled by it is the efficacy as it relates to mental health and the studies being done out of London around things like psilocybin and ibogaine and DMT treatments. And I just thought, wow, the clinical data is unbelievable. So I did a psilocybin and then I did DMT.

Andrew Huberman: I've not done DMT. I've done clinical MDMA and psilocybin. I think I'm done with that — not because I had a negative experience, but I got what I wanted out of it, and I found it to be immensely beneficial. The combination of therapy going in, therapy during, and therapy coming out of the combination of MDMA and psilocybin.

Steven Bartlett: Do you know what — it's one of the things that made me think a lot about religion. Having a DMT experience where what I experienced felt indistinguishable from this reality in terms of the vividness and the realness of it, and me just pondering this concept that a tiny little inhale of smoke could completely change my material reality. So therefore I concluded that my material reality is literally — tell me if my logic's wrong — a small amount of chemicals being uninterrupted. Does that make logical sense?

Andrew Huberman: Yeah. So I think about this way too much. I guess we are going to talk about psychedelics, reality, and religion. A couple of short statements about this. Most all of biology is just compartmentalised chemistry. So whether or not it's the flow of electricity along neural circuits to generate tenacity, or learning, you're just guiding chemistry in particular ways. That's not a way to trivialise it. It's a way to think about it.

There are two ways that you can change brain function, behaviour, and chemistry. One is mechanical — I can breathe differently, I can get a massage, I could poke myself with a knife. There are mechanical forces that change our physiology. And then there are chemical forces — pharmacology, things we eat, and chemicals within us: serotonin, etc. That's really it. There's no other thing.

In many ways, you're absolutely right. It's compartmentalised chemistry, and mechanics and other chemicals are what control that chemistry. And I think organising one's thoughts sometimes in that way can be helpful, because you realise the stress response is really just a bunch of chemicals happening in certain places.

I personally am intrigued about the idea of things outside of our conscious understanding in biology — that maybe things like DMT give us access to, or maybe just prayer gives us access to, or faith gives us access to. And it comes from my recognition, both as a neuroscientist and just a human who's been alive for 50 years and some change, that our biology and psychology are extraordinarily good at accomplishing certain things. But there are certain things that are outside the abilities of our psychology and biology. And if we are asking our psychology and biology to satisfy something that they simply cannot satisfy, we're going to miss out on a lot of potential meaning in life.

And to be very direct about it — at the point where I decided to really embrace the idea of faith, of a God, that there are powers outside of human understanding that can be very useful, everything got better. It relieved me of the pressure to control everything internally and externally. And I find it not just intriguing, but absolutely captivating that a force outside of us — some people call it God, the universe, some people might think it's Jesus, some people might think it's something else — might actually hold some power in how we could potentially behave, be better. Wouldn't it be wonderful if there's this thing planted in us, or some of us, which is a question about things outside of us, that if we were to embrace could allow us to get to a better place as a species?

Why would we think that a technology like AI would do that? AI is wonderful, but why would we think it would come from computers? That's of us. Why would we think it would come from anything that humans and only humans could do? To me, embracing the notion of a God and having faith — which by the way is about having doubt, but still doing the practices — prayer is to me one of the most liberating and educating things. Not just about stuff of God and the universe, but about the human brain.

Steven Bartlett: Do you believe in God?

Andrew Huberman: Absolutely.

Steven Bartlett: When did God come into your life?

Andrew Huberman: Very early, but I was very good at suppressing the notion that it was real. I would pray in private. I would hide it — and not just in bad times. And then I think I lived enough and observed enough hardship. I observed it out there too, not just in my own life. And I started to realise — especially if you stick your hands in enough brains, and you see my good friend Eddie Chang record from the brain of an awake human and remove a tumour and save that person's life, and you also realise that brain areas are controlling things because when they're stimulated, that person feels and responds in a certain way — you realise that we're not all meat and potatoes in there. There's something else. But I'm not sure that it all comes from us.

The best way I kind of wriggle out of this is that I brought my dad on my podcast. My dad and I for many years had a choppy relationship. We have a great relationship now. He's 83 years old. He's super vigorous. He loves ideas. He's into quantum computing. And he's a theoretical physicist. And I asked him to explain quantum mechanics. He worked on chaos theory. And he said, "I'll do that, but you have to understand that one of the most important things about understanding quantum mechanics is that early on you are told and you learn that the human brain can't wrap its head around quantum mechanics with logic, with human understanding. You have to rely on the math." And he says anyone who talks about the quantum field who can't show you the math, can't show you the proofs, is lying.

So what he was saying — and we were having a discussion about God — he said, "Yeah, at some point if you're going to have faith in a higher power, God, you have to depart from the notion that your logical brain can go from A to B to C and boom, you're there." But in quantum mechanics it's the same thing. But on the basis of quantum mechanics you can build stuff — you can engineer stuff in the real world.

Steven Bartlett: Are you saying there's no math to prove the existence of God?

Andrew Huberman: There's no math, and it's not worth torturing yourself over. What I believe is worth exploring is embracing the practice of prayer, embracing the questions, and opening the aperture of your beliefs just for a moment — going, "Maybe I'm going to just believe in God for ten seconds. See what that's like." And I started to experience beauty and peace around not trying to control things that obviously were not under my control — not just within me, but in other people. And I really started to see what I could only describe as miracles. By miracles, I mean I would pray for some indication of what the right path might be on something where it wasn't clear to me. And then two or three days later something would happen which would seem almost completely unrelated, and the answer would come in that thing. And then I just locked in.

I'm a disciplined guy when I really want to be. I'm going to pray every night before I go to sleep. If I fall asleep, I'll get out of bed and pray when I wake up in the middle of the night. I've not missed a night in nearly three years.

I was recently invited up to Stanford to give a talk with Arthur Brooks, who's a lifetime Catholic — he's in mass every morning. He and I have very different experiences of God and religion. My family was mixed religion. I got to sit up there and just say, "Listen, I'm going to tell you that I am for sure the person who's least knowledgeable, least versed in this room. But what I can tell you is my experience with prayer. What I can tell you is what I've observed in myself when I open the aperture for faith."

The reason I did that talk is because our former director of neurosciences at Stanford had written to me and said, "I think you should consider talking to this group." And he did some of the most important experiments in the history of neuroscience linking neuronal activity to perception. He really showed that if you stimulate certain brain areas, people perceive things a certain way regardless of what's happening out in the world. There's a brain area I could trigger right now and I could show you a movie of a bunch of dots moving up and everyone here would be like, "They're moving up." And if I tickled the right neuron in your brain, you'd say, "They're going down." And like that's wild. Then I turn it off and you say, "Oh yeah, of course they're going up."

Your understanding of the world is an abstraction that occurs inside your skull on the basis of photons that come in through your eyes, sound waves that hit your ears, mechanical forces that hit your skin, and chemicals that go in your nostrils and in your mouth. And then you abstract reality in here. Now, the laws of physics dictate how those things — like photons — have properties, sound waves have properties, and those are converted, transformed into signals. But then you abstract the world with enough accuracy that I can pick up this pen and not miss it.

So if you understand neuroscience that way, and then you go, "We don't see infrared in this room because we don't have the sensors" — but a pit viper does — does that mean there's a God? No, not necessarily. That alone doesn't prove that. But what it does prove is that we only have access to the physical events in the world that we have the filters within us to extract. You can't see it because you can't see it. You don't have the sensors. You can throw on infrared goggles and then you can see it. But that's a technology. I don't think there will ever be the God goggles. The emotional goggles, so to speak, come from this thing that we call faith. Faith is the infrared goggles of human understanding about why we're here.

And the challenge for people is I feel like people come in at least three categories. They either had religion forced on them in a bad way so they hate it. They never had access to it in a way that made them gently pulled toward it. Or they are absolutely convinced that it can't be, which I look at as a sort of spiritual anorexia. You know, there are regions of the brain that when stimulated, people get the experience of God — not as themselves, but they feel it. And people have said, "Oh, well then there's a God region of the brain, and it's just a brain region. That can't be." But we have brain regions. Arthur says this much more eloquently than I could. There are brain regions for thirst, which in the philosophical way would say, "Well, that proves the existence of water." The thirst proves the existence of water. So I have a thirst circuit for gaining understanding of this thing that we call life and whatever comes after it. And in that thirst, I decided to open the aperture to the idea that the stimulus — the water, the photons — I'm not able to extract that through thought, through my eyes, through my ears.

Just like my dad couldn't come to understand quantum mechanics by thinking really hard about it — you have to do the math. And there are gaps in my reasoning here. It's not a perfect one-to-one. But also life's just so much better. I don't think anxiety sticks in us very long if we're feeling anxious and we pray, "God, please help me remove this." It's not "do this for me." It's "help me put energy in me to do the right things today. Put energy in me to serve people." I prayed before I came in here. I get on my knees before every podcast — guest or host — and I prayed. I said, "Please help me move my ego out of the room. We all have an ego. Help me maintain humility. Help me strive for clarity. And help Stephen and I do something that we're not predicting that would happen but that we want to happen, that we don't understand."

And maybe that's this part of the conversation. I don't know. And the point is not to know. It's also fun as a scientist who loves mechanisms and cells and circuits and neuromodulators — it's enriching to have a part of life that I can just explore. Science is about mysteries and it's about solving mysteries, but it's also about being in awe of the mystery. And I'm all in. Life is still plenty hard. But I love it.

Steven Bartlett: It seems to be an antidote that a lot of people are reaching for now, based on the way that we've kind of designed our lives over the last couple of decades — the individualism, the loneliness, the nihilism, the me-me, the material success, the low-level narcissism of being on social media and trying to get as many followers as you can. And we've become islands. I've been thinking a lot about this idea of God and meaning, because it does appear to me that we are meant to be anchored to ourselves and our family and then our community and then maybe our city and then maybe our country and then maybe the planet and then something above.

Andrew Huberman: I mean, you're an ambitious guy. Go bigger. The biggest thing is that there is a non-human force in the universe that wants goodness and can exemplify perfection. And you and I — if I may — by virtue of being human, by virtue of having circuits — the famous studies where people get to stimulate different areas of their brain — you know the area that people like to stimulate a lot, the area that generates frustration and anger, that arousal. I saw that result and I was like, "Oh man, that's disappointing. Why not beauty, giddiness, or even feelings of being drunk?" Though they found that too, but they were not as interested in that.

Are we bad? No, we're not bad. We are wired with an animal part of our brain and we are wired with a conscious, thoughtful part of our brain. And it's a lot of work to ascend — to ascend as a human to a place where you're living in a controlled and thoughtful and peaceful way with yourself and with your pursuits, and you're striving to put goodness in the world and take care of people. And to do that with a little less friction — I know from experience that comes from trying not to control every aspect of every process, and somehow everything just goes much better.

People will be like, "Oh, he really drank the Kool-Aid." I actually think that this was pumping in my veins from the start. Yes, I worked on a lot of topics — stress, vision, etc. But I studied neural development for a long time. You know, sperm meets egg and cells start dividing and you get a human. Yes, we understand induction factors. I teach developmental biology, cell migration, axon guidance. Great. Compartmentalised chemistry can give you a human, but there are gaps in our understanding, and there's magic in that orchestration that goes beyond what the science can even begin to understand. And it's nothing short of spectacular.

Who doesn't want more awe in their life? Dr. Dacher Keltner is the awe guy at Berkeley. He said awe is when you go from small aperture to big aperture and from big aperture to small aperture. That transition induces awe. And you can hear it in sound too. Like when you walk in off the street and you go into — Stanford has this incredible church, Memorial Church, unbelievably beautiful with this giant organ — and you walk in there and people change. Not just because it's a high ceiling and you're like, "Wow, this is incredible." Of course I know humans made it. But that transition — day aperture to holy aperture. And you can get this other ways. I'm not saying you can't. But I like the idea that if we dial out really far, there's something much greater than us. And I don't know exactly what form it takes or exactly what shape it takes or exactly what ways that God would exert influence over our minds. But you don't need to.

Steven Bartlett: This is the thing that I have to come to terms with. I go, "Okay, this is really interesting. There's lots of meaning and benefits to my life." And then I go, "Okay, so which Bible have I got to believe?" And then I start looking at the Bibles and I'm like, "Okay, Noah's Ark."

Andrew Huberman: Look at a bunch of them. I think one will call to you more than the others. Listen, it may end up being atheism for some people. But when I said spiritual anorexia earlier — anorexia is the most deadly of the psychiatric illnesses. Something happens to the neural circuits where people with true anorexia feel some sort of sense of reinforcement — better than reward — from avoiding food as opposed to eating it. So that runs against our evolution as a species and our health. But the desire for food, as Arthur would say, proves the existence of food. The desire of thirst proves the existence of water.

And there are atheists who are like, "Yeah, I don't need it. Not for me." And then there are atheists who have a kind of spiritual anorexia. It's almost like they get their spirituality from not believing in a God. And I look at them and I go, "Well, you're kind of on the same extreme." It's almost like it wraps around so far that the truly religious people and the atheists kind of meet right here. They both have the same sort of thing, but there's kind of an inversion of the circuit. Someone will work out the neuroscience or not. I'm going to keep praying because my life is that much better.

Steven Bartlett: When I heard you talk about it, I started praying a little bit. Not all the time, but there are several moments where I thought, "Do you know what? Now would be a good time to just pray." And someone like you saying that you do it gives a lot of other people permission to try and to investigate for themselves. Because if I'm in the human camp — maybe I'm someone that really cares about scientific rigour and precision — and then if you change that camp to also be open-minded to spirituality and religion and these other pursuits, I can still be sort of ideologically who I believe I am while also investigating these other things. So when I heard you talk about prayer, it was really impactful for me. It gave me permission, I should say, at some weird level, to also investigate. And I report the same findings as you — it helps.

Andrew Huberman: My former chair and director of neurosciences at Stanford, who encouraged me to do that talk at Veritas, where I mostly talked about how ignorant and naive I am on these topics — he's a brilliant neuroscientist. He has faith. And I respect him and I respect his mind.

I also think there's a kind of fun analogy here that just came to mind. This happened during the pandemic with the health community. When you're a kid, you think your parents are everything. You think they can do no wrong. And then there's this thing called being an adolescent teenager, and you catch them lying or saying things occasionally, and all of a sudden you're like, "You don't know anything." Then you gain some agency and some philosophy in life and you get to this point where you think you know everything. And then as adults, we eventually get to the place where we go, "Oh, wait. I'm looking at humans for something that isn't going to come from human beings. We're all flawed. We're all imperfect." And so the notion — the belief — that perfection exists outside us, and that we can strive for certain things through works, through practices — that's not just compelling, that's just downright fantastic to me. Because it allows you to fully embrace the woes and the beauty of being human in embracing God. It's kind of a weird thing. More power to the atheists if they can pull it off without all that. But meanwhile, I'm going to keep at it.

Protocols eight and nine: sleep environment and focused learning

Andrew Huberman: So at night, once you're asleep, try and keep your sleeping environment as dark as possible. A good eye mask is useful. Some people like earplugs too. If you wake up in the middle of the night, do some long exhale breathing or do the wacky eyes to the side, eyes up, counterclockwise and clockwise. At night, dim the lights. Why? Bright lights stimulate cortisol release. You want your cortisol low at night. Everyone says, "Yeah, dim the lights because it suppresses melatonin." That's true, but that's just half of the story. The other reason is it increases cortisol, and you want your cortisol low at night.

Steven Bartlett: What about this whole conversation around phones at night and blue light?

Andrew Huberman: Dim your phone, or triple-click to program it to go to the red screen. I think in the last 30 minutes before sleep — no screens. And the first 30 minutes after waking, you should be looking at the sun and exercising, hydrating, and doing that kind of thing.

You need to do a bout of work of 90 minutes to two hours. You've got to strive and try and learn something. Do something hard every day mentally. This is critical for your ability to focus. And by the way — awesome study came out. They had people with their phone off upside down on the table, or in their bag underneath their chair, or in the opposite room. And what they found is people can focus just fine in all three conditions. But if the phone is anywhere in the room, the amount of cognitive flexibility they have with the material they're focusing on is diminished. In other words, it requires more energy to focus. Even if they're not getting calls and notifications, there's a subscript running in the brain apparently that's anticipating that this thing is going to reach for them. So it's calling you even if it's not calling you. And so the way to increase focus and cognitive capacity is actually to just get the phone out of the room.

Visual field matters a lot too. The kid in school with the hoodie who's not asleep — that actually is helpful. I talk about some of the history of tools for focus — pharmacology but also physical devices. They used to design helmets for kids to try and focus the kids that had trouble. The problem is now with the phone you've moved the whole world right in front of you. So focusing just here doesn't work. But get the phone out of the room and do some effortful learning, and it should feel like a fight.

Keep in mind the friction you feel trying to learn something — that's adrenaline. Remember, how do we block learning? We block adrenaline and its downstream effects with propranolol. Being alert but calm, or a little stressed, and making errors through deliberate attempts to do something — not just throwaway errors — that's how you learn. Why? If I can reach out and grab this pen, my brain doesn't change. One of the biggest lies in public education about neuroscience is that every experience changes your brain. "By the time I'm done saying this, your brain will be different." No, that's absolutely not true. I studied neuroplasticity. I teach neuroplasticity. You know what induces neuroplasticity? Being a baby who's trying to learn, or being an adult who's forcing yourself to try and learn something you can't do. The error is what stimulates the plasticity.

The appropriate level of difficulty — the computational modelling suggests somewhere around 15% error rate on average. There are two kinds of practice. One is practising doing things you already know how to do — there you're aiming for 100% performance. You're reinforcing what you already know. Talk to a great dancer and they'll tell you they drill, drill, drill the things they already know how to do. But when you're trying to learn the new language, the new emotional skill, the new physical skill, you need to make genuine attempts and you need to fail some of the time. And those failure signals are relayed to your cerebellum, and your cerebellum propagates through networks that say: change.

So there's a set of conditions in the chapter on plasticity. You need to be alert — I talk about all the ways you can get alert, including pharmacology, supplements, and behavioural tools. Then you need to be focused — I talk about all the tools for focus. And then I talk about the conditions for plasticity: you need to get this friction and these errors, and then you need to stop. You need to come back a day or two later, do it again, and then you need to make sure that you reinforce what you learned.

Here's where AI is going to be a wonderful tool — already is a wonderful tool. The best way to learn is to not forget, meaning if you test yourself mentally. You could use any one of the LLMs, but I'll go into ChatGPT and I'll just say, "Generate a short test of graduate student at Stanford level questions about neuroplasticity," and I go through it and I remember this — there's this one thing I don't remember. That's how you maintain and build knowledge over time. Self-testing. People hear the word test and they think of an external tester. You're the test taker. Self-testing.

Steven Bartlett: That's a really interesting idea for this podcast episode. Team, should we generate a quiz? We can take the transcript and turn it into a test.

Andrew Huberman: Awesome. ChatGPT is great at doing this. You can change the difficulty and you can actually say, "I'm a professor of neuroscience and I want a 15% error rate on average." The study I love that really backs this up is that there have been a lot of studies of learning where they have students read the same passage one, two, three, or four times, and then they also have them highlight or take notes, or they just have them read it once and self-test. And they look six months and two years later. Reading it once, no notes, no highlighting, and self-testing about a week later — looking up what you couldn't remember or got wrong — led to much more stable learning over time.

Now, this doesn't work so well for physical endeavours, because there you have to actually do the physical thing. But I love that set of experiments because it tells us everything we should be doing.

So I think in doing this for me — it could be a book. Lately I've been podcasting and recording my audio book. Have you done a book?

Steven Bartlett: Yes. And I did the audio book, which was horrific.

Andrew Huberman: Are you due for another one?

Steven Bartlett: I am. I've actually written it already. I finished writing it last year.

Andrew Huberman: Oh, man. What's it about?

Steven Bartlett: It's called Just Do It. I asked the audience multiple times what they wanted — I showed them multiple covers of books, hundreds of them — and that was the one that most of them tried to buy. And it's really just a breakdown of how to do the thing. And actually I referenced you in that in the chapter about the anterior mid-cingulate cortex and what you said about it.

Andrew Huberman: Well, to be clear, I didn't discover that structure, but I'm happy to expound on all its incredible abilities.

Steven Bartlett: I just quote what I heard you say about it in your podcast.

Andrew Huberman: Cool. I'll get a copy. I'm late to the train obviously.

So I think it's enriching as a person. It's not about optimisation per se. It's about being a human being and learning and effort that's followed by learning and reward — especially for things that may not immediately benefit you, but just to enrich your mind. If you're interested in the history of medicine, read a hard book — The Prince of Medicine about Galen. If you're interested in light, there are a bunch of cool books about sunlight coming out now from people other than me. There are just cool books out there.

Steven Bartlett: But this is linked to brain health and dementia, these kinds of things.

Andrew Huberman: To some extent, yeah. The data on dementia say that people who stay mentally and physically active and are socially enriched do much better. In fact, Masud Husain — who is this brilliant neurologist from Oxford — has been talking about patients who it turns out live a very long time, have lots of plaques and tangles — the signature anatomical features of Alzheimer's dementia — but no dementia. And these people are exercisers and they are people who stay very avidly engaged in learning. So there are a lot more people with quote unquote Alzheimer's walking around. They have all the diagnostic features of Alzheimer's except the memory loss and dementia. This says that to some extent the physical ramifications of Alzheimer's and the consequence of those changes in neurons are somewhat separable.

He also told me that there are patients who have Parkinson's who can't generate smooth movement, but if they have to escape a burning building they can — which is interesting, a little frustrating as a message because it could potentially send the wrong message, like they're just not motivated enough. But it points to the fact that if motivational systems are high enough, there may be alternate motivational systems. In the same way that kids with very severe ADHD — if you give them a video game they love, they are locked and loaded. They're in a focus tunnel for two hours, which tells you they can focus, but not on things they're not really interested in. And a lot of life is about forcing yourself to be interested in things you don't really want to do.

Protocol ten: personal development

Andrew Huberman: So that's number four. We got one left. Number ten — to frame this a little bit. The last chapter of my book is on personal development. I thought a lot about whether I was going to write the last chapter on relationships. That seemed like a no — not because I haven't had them or not because I haven't had some great ones, but because I think people who work on that as their academics should do that. In any event, I decided to write about relationship to self. And then I thought, no, personal development is something we're all trying to do.

Here's the key question set up at the beginning. I talk about grief and what the science of grief is and how to navigate grief. But early on in that chapter on personal development, I sort of set it up the following way. I look out on the landscape of all the personal, psychological, and relationship development stuff out there — online, in books, in papers — and it looks like there are sort of two bins. One is how to find what's important to you, do what's best for you, and be the person you're supposed to be for the world and maybe for you also. And then there's this other bin, which is that we need to be very careful about pursuing things and fulfilling roles because we can get very far off track from our core — what Martha Beck would call our essential self. I'm a huge fan of her work, in no small part because she talked about that in her books, which were very, very impactful for me. But she also has three degrees from Harvard. So this isn't somebody who can't get stuff done.

So I hosted James Hollis, this 84-year-old Jungian analyst on my podcast. And he just wowed the heck out of all of us. He basically said this — mind you, this guy's written books like The Eden Project on relationships, he's written books like Under Saturn's Shadow on the healing and trauma of men. He's a brilliant thinker. And he said, "Look, there are three things you've got to do every day." And he encourages his patients to write this on their refrigerator or carry it around with them.

He says, "First, shut up." I'm like, "What? I thought it was going to be like this nice Jungian analyst." He goes, "Shut up." There's always somebody suffering more than you. You have to have gratitude. You have to have a gratitude practice. So I spent some time talking about what that really looks like, because there's a science of gratitude and then there's the common understanding about what that is. It's really about receiving gratitude, yes, having a gratitude practice of all the things that are good in your life, but really it's about giving gratitude and receiving gratitude.

The second thing he said — so I go, "Okay, now he'll kind of soften up" — and he says, "Suit up." You're not going to be able to do well in anything in life unless you prepare. Get up in the morning, take care of your health, do what you need to do — shower, brush your teeth, get organised. This sounds a little bit like Jordan Peterson's "Clean Your Room," but it was even edgier than that. It was like, how in the world could you perform well on an exam or in a relationship or in a sport or at work if you don't actually do your homework?

And then he says, "And show up." He said, "Happy people fulfil outward roles for the world. They fulfil roles — father, mother, sister, brother. They look at themselves as somebody who needs to fulfil roles. Teacher, mechanic, engineer, podcaster. But you have to shut up, suit up, and show up. You need to fulfil roles. There is no human being that doesn't have to do stuff for the world. You can't freeload."

But then he said there's this other piece: if you carry on like that for 10, 20, 30 years, you can end up quite happy, but most of the time if people just do those things, they end up pretty miserable. And I was like, "Oh man." And he said the other piece is once a day you need to get out of role fulfilment. You need to get out of preparation, suit up, and you need to get out of trying to be more grateful — you still need to do that — but you need to get out of that and you need to go into what he called exiting the stimulus-response mode of being. Which could be sitting quietly in meditation. It could be drawing, listening to music. You're not trying to accomplish anything. And you're just letting your unconscious mind feed you information about what he called your deepest heart's desires.

And I was like, "Yes, this is why we go camping." He said, "Yes, you can take longer extended breaks. You can go backpacking. You can run. You can allow this to happen in any number of ways. But once a day, take some space for yourself and just touch in with self."

Now, if you're sitting there going, "Okay, what do I want to be when I grow up? It should happen" — it's not the way it works. Your unconscious mind speaks to you in emotions, in analogies, and it sets you up to go back into life to be able to see connections and start navigating in new and interesting ways — ways that are unique to your heart's desires about what you like and what you don't like. And to know that those choices are in goodness and in keeping with who you are.

I can't tell you what your deepest heart's desires are. Only you can come to that clarity, but you need to do it through a practice where you're not trying to be the football coach, the mom, the best this. You need to listen to yourself. But you also need to keep fulfilling those roles. Because he and I both agree — and I mention this several times because I get asked all the time, "How do I find my calling?" You find it while working your butt off doing something else. That's how. You don't sit around going, "That's my calling."

Steven Bartlett: You work your butt off doing that something else and you hate it. So you do something that you hate a little less, and you do something you hate a little less maybe, and eventually you get pulled forward to this thing that is your key self. And there's not necessarily a single one — because people often, when they talk about finding your passion, "passion" is a word that happens to be singular, which can be somewhat distorting. Because then you think, almost like an Easter egg, "I have to go search for it and there's going to be one of them somewhere."

Andrew Huberman: I can handle five-year chunks. Maybe this just reflects my years and years of getting degrees — it's like three to five years for this, then three to five years for that, post-doc, graduate school, etc. I'm navigating from 50 to 55 now. That's what I know. I know what I'm going to carry forward — exercise, faith, hydration. I know what I'm going to carry forward, but I don't know what's coming next. I've never been 60 before.

Sleeping on your side and glymphatic clearance

Steven Bartlett: So the end of the day — there were two questions that I had for you here based on some of the research. The first is a technical one, but sleeping on your side. I heard there are different outcomes for your brain based on how you sleep at night.

Andrew Huberman: When you sleep, you have a washout of waste products from the brain. Very important for offsetting dementia. Very important for feeling rested. And if that's not enough incentive, very important for getting rid of bags under your eyes. You know, in the morning when you've had one night's terrible sleep — have you ever seen yourself after one night's bad sleep?

Steven Bartlett: Oh my gosh.

Andrew Huberman: Right. Sleep two nights well. You see yourself?

Steven Bartlett: Yeah. What the hell?

Andrew Huberman: You're your handsome self again. So what is that? That's accumulation of lymph and other fluids and waste products. During sleep, there's this lymphatic clearance. And it does seem it can be slightly but significantly improved by sleeping on your side with your head slightly elevated. We used to think it was slightly inverted. Now we think it's slightly elevated.

When you get up in the morning, I'm actually a big fan — I've got one of these inversion tables, but most people won't — where you lie back and go upside down. This feels good on my back. But some people get the shakes. Some people do some jump rope. You can just kind of shake out and move, because the lymphatic system is really incredible. It's one-way valves stacked up from your feet all the way up to your brain. People think about the role of lymph and lymph nodes in immune checkpoints and the immune system — that's all true of course — but the lymph system is taking liquid and dumping it back into your blood circulation. It can accumulate when you're lying down. Lymphoedema is swelling of the lower limbs. So you need to move. When you move, you're essentially squeezing the lymph in these one-way valves up to dump back into the general circulation.

Your brain doesn't have that mechanism. So miraculously, in sleep, you get the astrocytes — the glial cells — actually create a bit of extra space in the brain between neural tissue that allows the waste products — the glymph, as we call it, glial lymph — to flow up and out towards the surface of the brain, and then it dumps out of the brain — still in the body of course — and down and out. Actually, the puffiness of the eyes, the anterior chamber of the eye, some of the cloudiness of the eye — these systems are shared, and actually some of it actually comes out through the nose, which is wild.

But get upright, move around. There are a bunch of ways — these like tapping and shaking, it looks silly, it looks kind of crazy, looks like you've been in California too long if you do these things. But it can help move lymph out. But sleeping does that — it clears glymph.

The other thing — there's a recent study published in the Proceedings of the National Academy of Sciences that I do detail in the book — which is that a short meditation, believe it or not, increases glymph clearance in the daytime. Now, this is super interesting because folks like you and me always want to figure out how we can get by with less sleep and still feel awesome and not short-circuit our health. It turns out that regular meditators are probably able to shave an hour off their sleep — 20 minutes a day of meditation — because they're getting the glymph clearance during their meditation.

And so in sleep, the timing of sleep and how long you sleep has a lot to do with body temperature, but also there seems to be a drive for glymph clearance that says you need to sleep longer, which is one of the reasons why when you're sick, you sleep a lot more.

So I'm now back to meditating. And my meditation practice is pretty feeble compared to many. But here's what I do. I wake up in the morning and the first thing I do is ten breaths of meditation. I tell myself: if I can't concentrate for ten breaths without my mind going elsewhere, what kind of day am I going to have? And also, what kind of human am I if I can't organise myself for ten breaths? Then I get out of bed, I usually go straight to the bathroom, pee, then I go hydrate, then I get sunlight, then I try and get some movement. Although these days, because of the dog, I get a walk in. Then I come back, drink some caffeine, exercise, and the ten steps start all over again. We are this rhythm. No human being has ever escaped these circadian influences in cortisol and melatonin.

Supplements

Steven Bartlett: Do you take — you don't really talk in depth about supplements or recommend supplements?

Andrew Huberman: Oh, I do. I always get asked what should I take. I talk about alpha-GPC, L-tyrosine. I talk about theanine. I talk about theanine's use with low-dose caffeine for enhanced task switching, which is a very interesting literature. I talk about ways to improve sleep — everything from tart cherry to apigenin to quinine — which is one of the orexin drugs. I go ham.

Steven Bartlett: So if you had to pick five — if they said to you, you can only do five for the rest of your life — what five supplements would it be?

Andrew Huberman: Well, if somebody's sleeping terrifically well, I'd say nothing for sleep. If they're not sleeping terrifically well, I would suggest they try magnesium threonate or magnesium bisglycinate. They're interchangeable for sleep. Okay, that's one.

I'm a big believer in getting at least one gram per day of EPA omega-3. I suggest getting it in prescription form — Lovaza — because it's now available generic and cheap. That form of omega-3 is what you want for brain health, probably also for cardiovascular health and reduced inflammation.

Steven Bartlett: How do I know if that's the omega-3 that I have?

Andrew Huberman: You need a prescription. But here's what's awesome about it. It's very high concentration EPA and it's cleared of all heavy metals. And it's very, very inexpensive. So the challenge is getting a doctor to prescribe it for you. Just tell them you want Lovaza or else you're going to take a bunch of stuff over the counter and you might get mercury poisoning. Don't threaten your doctor, but you get the idea. So that's for mental health, physical health. Big believer in boosting omega-3s. Also, I don't eat fatty fish. I don't like salmon unless it's sushi, and I'm just not good at eating seafood. So that's two.

Vitamin D — 5,000 to 10,000 IUs per day. People say, "Oh, you don't know that. You need to blood test. You don't want to over-" — okay, don't take 25,000. But most people are underdosing vitamin D. I'm not trying to just hit the RDA. I'm also not trying to blow a gasket by taking too much. I'm trying to get to a point where I can derive safety but additional benefits. And it's clear that dosing of 5,000 IU per day has some additional benefits that go way beyond conventional benefits of vitamin D. For instance, hormone health. I can see my bloods getting better when I take 5,000 as opposed to 3,000 IU of vitamin D, and I'm not changing anything else. So vitamin D — and I get sunlight. Maybe 10,000 was a little high, but I take five to ten. So that's three.

And then the other two — if you're going to exercise or work intensely late in the day, or if you really want a stimulant to go with your caffeine — by the way, 90% of the world consumes caffeine every day, so that's a foregone conclusion — I am a big fan of alpha-GPC. 600 milligrams or 900 milligrams of it. It increases choline, which increases acetylcholine, which can increase your ability to focus. I'm a big believer in this — not for everyone, but rather than going straight to a prescription stimulant. And I'll tell you why. There are very, very few things that can increase focus and energy that don't damage your sleep. But even better, alpha-GPC gives you more REM sleep. Nobody wants to hear this, but it's absolutely true.

But the important caveat is that it can increase something called TMAO, which can increase cardiovascular risk. So a simple way to mitigate that is you take 600 milligrams of a garlic capsule — and it doesn't smell like garlic. So I kind of tuck that in with it. And you can take it anytime, same day.

Steven Bartlett: Is that five?

Andrew Huberman: That's five because I threw garlic in there. No — we said magnesium bisglycinate or threonate, omega-3, vitamin D, and then alpha-GPC would be my preferable thing to nicotine or prescription stimulants. And caffeine — great data on caffeine. In fact, 200 to 400 milligrams of caffeine per day has been shown to offset dementia in meaningful ways. It's not causal, it's correlative, but those data are covered in there as well. So I'm going to continue drinking my yerba mate and my coffee.

And then the last one — creatine. Yeah. So creatine seems to work best for cognitive enhancement when you're a bit sleep-deprived or stressed. I've been taking creatine since I was 17 or 18. Five to ten grams per day. I like it because I'm trying to maintain or build strength, and it puts water in your muscles. It makes you stronger and it feels good to be strong.

Walking, glucose regulation, and metabolism

Steven Bartlett: The last thing I want to ask you about — I saw a clip, I think it was one of your most viral clips of all time, where you just talked about how going for a walk after you eat can have a really big impact on your body that most people don't realise.

Andrew Huberman: Most people don't realise. There's a section — I think walking is necessary but not sufficient for health. I don't think you need to count 10,000 steps per day, but I think 7,000 to 8,000 steps per day should be the goal. You can do it. I'll pace while I'm on calls. I take every — when I finish a podcast with my team, we take a walk. I'm always trying to take stairs. When I travel, I take stairs, not the escalator. You arrive a little sweatier to your plane, but you're also rucking your bags.

So walking is incredible because those low-level repeated muscle contractions really help buffer blood glucose, especially after a meal. But there's this wild study where the soleus muscle — the one that gives the calf its width, when you do seated calf raises it's this muscle underneath the gastrocnemius — that muscle is about 1% of your total musculature, but it has an outsized and significant glucose utilisation. In this study — which is not practical — they had people do what they called soleus push-ups, which are basically non-weighted seated calf raises while sitting, and they had them do it repeatedly. And they looked at blood glucose regulation, and it powerfully regulated blood glucose. It buffered the peaks. And it turns out that this is related to walking.

So I'm not suggesting — unless perhaps you're stuck on a plane or in the office — that you do this all day. But if you're a knee bouncer, rejoice. You're doing yourself good. This movement really seems to help blood glucose management.

Steven Bartlett: And why does that matter?

Andrew Huberman: You don't want big peaks in glucose. You can manage them — more insulin will be secreted if you have a big peak in glucose. That's why insulin's there, to make sure that glucose is managed. You don't want it too high. You don't want to be hypoglycaemic — in fact, that can be deadly. But when people eat, they experience an increase in blood glucose. And while the peaks are manageable, if you're buffering them — so you're flattening out those peaks with five to ten minutes of walking after a meal — you will have fewer energy crashes. In theory, over time, your metabolic health can be better or at least cannot get worse.

Dr. Rhonda Patrick has pointed out there's a sort of comparison study where people either walked after meals for 30 minutes or so per day, or they did ten air squats every 45 minutes — just stand up and do air squats — and it looks like they were comparable. Maybe the air squats were better. I don't know about you, but I'm not going to stand up and do air squats in a restaurant or when I get out into the street of New York if I have the great experience of having dinner with you and James Staton again. We're going to walk. So I think — and I'm not being disparaging of Rhonda — I think she was pointing out a mechanistic feature, not necessarily a protocol. But if you're stuck on a plane, you could do some air squats. You could bounce your knee.

Non-exercise-induced thermogenesis is a massive calorie burn. People who move a lot tend to be rather lean. I go back to my undergraduate days when we worked on metabolism and physiology — Rothwell and Stock and some other folks, these scientists who figured out that there were people who could eat a lot more than you would think they needed but they always stayed lean. Turns out they're moving a lot during the day, burning up to 1,800 calories a day. Now, that's extreme, but some people who just move a bit more burn an additional thousand calories per day.

And there's this paper published in the journal Science — which is a great journal, not as great as Nature, but the Brits get the cake there, and people will argue, but it's true — that the decline in metabolism that we all associate with ageing, like, "Oh, metabolism slows as you age" — turns out that's not true. Turns out that if people maintain muscle mass, that doesn't happen. And you say, "Okay, well, then ageing is muscle mass loss, which is reduction in metabolism." Actually, no — people are moving less.

I've been absorbed, as everyone else has been, with this longevity thing. I look at older people — in particular people in their 80s — and you know what I see? A lot less spontaneous movement and a lot of mouth breathing, which at rest is not good. We know this — it deprives the brain of oxygen. You can mouth breathe during exercise, physiological sighs, etc. But you don't want to be a mouth breather in sleep or in wakefulness.

And then you host people like James Hollis or Twyla Tharp — I don't know her exact age, I think she's in her early 80s, but she's a choreographer, world-class dancer who deadlifts a lot and works out for two hours a day at 5 in the morning, who boxes, who choreographs. They're so mentally sharp. They're physically lean. And you go, "What is happening?" Mike Snyder, my colleague at Stanford — you look at them and you go, "What's going on?" And they're moving all the time. They're mentally active. They have great posture. They're exercising, sure, but they are moving, moving, moving. The spontaneous movement is burning calories — that's one piece — but it's also the glucose regulation.

Layne Norton has pointed out quite beautifully that what's the problem with caloric excess? Okay, there's the body fat aesthetic piece. But that aside, it's that you have a toxicity of energy. The world's expert in mitochondria came on my podcast recently — Jared Rutter. He's phenomenal in the biochemistry and the genetics of mitochondria. And he will tell you: when you overload a system and therefore a cell with calories, the mitochondria, the whole system gets sick. The energy management system of a cell gets sick. And your metabolism — this thing that you call your metabolism — is the collective makeup of all these trillions of cells. So you jam too much fuel in there, and they don't work as well.

And caloric restriction at times might be beneficial. Caloric maintenance, maybe a little bit more at times, a little bit less. This is good. So movement, movement, movement — because it's obviously calories in, calories out.

Steven Bartlett: You know what this is, right?

Andrew Huberman: This is a CO2 monitor.

Steven Bartlett: I thought it was a lux meter. How high — oh, we have a lot of CO2 in here.

Andrew Huberman: Yeah. It's something that we always have in the studio because I learned over time that the higher this got, the more sort of tired I felt. And obviously because there's not great ventilation in this studio here. We started at 600 and we're now at 1,700. And we're under short wavelength light. But before we came in here, what did we do? We went outside and we had a blast of full spectrum sunlight.

Steven Bartlett: Yeah. I always think about this a lot now when I'm trying to do good cognitive work. I read some studies that if this gets above a thousand parts per million, cognitive performance starts to go down.

Andrew Huberman: Well, if your cognitive performance gets any better, we're all hosed.

Steven Bartlett: You're very kind, Andrew. Thank you so much for so many reasons. It's such an honour to get to learn from you. There's no books that I've been waiting for in my life — is there any book in my life that I've been waiting for? No, there's not. This is the only book in my life that I've been waiting for for years now. And I say that because I believe in your approach, your scientific rigour, the nuance you apply, the stories that you tell, the experiences you've had, the almost mesmerising ability you have to remember things, to remember names. You didn't reference one study without referencing the author of the study. I was thinking, "How has he done that?"

Andrew Huberman: Years and years of training and advisers who drilled into me that attribution is important.

Steven Bartlett: It's remarkable. There's so much information out there around health and all the things that we've covered today. But I was waiting for your book because I'm not very good at reading books.

Andrew Huberman: Well, there's an audio version too if you prefer. It'll be a long run.

Steven Bartlett: No, I'm trying to build the anterior mid-cingulate cortex, Andrew. I always said to myself, whenever he publishes that book, I will read the whole thing from cover to cover. And this is the first book in the world I believe that's been printed.

Andrew Huberman: Yeah. Can I — this is an opportunity to say what I've been waiting this entire podcast to say. The copy you're holding in your hand is the very first and the only hardcover copy that I have or have touched or have seen. And I'm gifting it to you. I want you to have the book. Seriously, I want you to have it. And I'll sign it if you want, or not sign it if you don't. But it would be an honour for me to be able to do that, because I've learned so much from you. You've been an amazing colleague and friend and supporter, but also just a truly good human being. And I've spent time with you on and off mic, and you know the number one thing that you need to know about Stephen is he is who he appears to be. He's a super kind, curious, loving person. Flawed like the rest of us, albeit less flawed than me — that's clear. But you really are a great human being and you're trying to do great things in the world, for everyone around you and for the world. So it's a vastly lesser token of my gratitude to you for all those things than it could be or should be, but I'd like to give it to you.

Steven Bartlett: No, it's such an honour. I was thinking of ways to steal it. So glad you're gifting it. Thank you so much. It's such a beautiful book and I'm really glad that it netted out at the size that it did as well. I think it's the perfect size. And I think you've done a wonderful job of making it really accessible, because I'm not the smartest cookie as it relates to science, but I was able to understand everything, and I think that's a really remarkable thing. It is also gorgeous.

I dare I say — and I'll probably get grief for this — but I think sometimes the British version of books is good-looking and then the American versions, I always wonder why they're a little bit uglier. The aesthetics in Britain — people dress really well in Britain. They take care. They pay attention to these little details, like in their shoes and things. Smart. Like they dress really smart. I'm a big fan of Ben Sherman and Fred Perry clothes and things like that, and the details are what make those look so cool. Well, this felt like a very European-designed beautiful book.

Andrew Huberman: Thank you, Stephen. I've learned so much from you. You've got to get the book. It's finally here. It comes out in September, so this episode will air in September. It should be out now for pre-order or order. For me it's the definitive book on this subject. Thank you so much.

Steven Bartlett: Thank you. Love this conversation. I hope to have another conversation sometime soon.

Andrew Huberman: Yes.