Huberman Lab - Boost Your Energy & Immune System with Cortisol & Adrenaline

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Welcome to the Huberman Lab Podcast,

where we discuss science

and science-based tools for everyday life.

I’m Andrew Huberman,

and I’m a professor of neurobiology and ophthalmology

at Stanford School of Medicine.

This podcast is separate from my teaching

and research roles at Stanford.

It is, however, part of my desire and effort

to bring zero cost to consumer information

about science and science-related tools

to the general public.

In keeping with that theme,

I’d like to thank the sponsors of today’s podcast.

Our first sponsor is Athletic Greens.

Athletic Greens is an all-in-one

vitamin mineral probiotic drink.

I’ve been taking Athletic Greens since 2012,

so I’m delighted that they’re sponsoring the podcast.

The reason I started taking Athletic Greens

and the reason I still take Athletic Greens

once or twice a day

is that it helps me cover

all of my basic nutritional needs.

It makes up for any deficiencies that I might have.

In addition, it has probiotics,

which are vital for microbiome health.

I’ve done a couple of episodes now

on the so-called gut microbiome

and the ways in which the microbiome interacts

with your immune system, with your brain to regulate mood,

and essentially with every biological system

relevant to health throughout your brain and body.

With Athletic Greens, I get the vitamins I need,

the minerals I need,

and the probiotics to support my microbiome.

If you’d like to try Athletic Greens,

you can go to slash Huberman

and claim a special offer.

They’ll give you five free travel packs,

plus a year supply of vitamin D3K2.

There are a ton of data now

showing that vitamin D3 is essential

for various aspects of our brain and body health.

Even if we’re getting a lot of sunshine,

many of us are still deficient in vitamin D3.

And K2 is also important

because it regulates things like cardiovascular function,

calcium in the body, and so on.

Again, go to slash Huberman

to claim the special offer of the five free travel packs

and the year supply of vitamin D3K2.

Today’s episode is also brought to us by Element.

Element is an electrolyte drink

that has everything you need and nothing you don’t.

That means the exact ratios of electrolytes are an element,

and those are sodium, magnesium, and potassium,

but it has no sugar.

I’ve talked many times before on this podcast

about the key role of hydration and electrolytes

for nerve cell function, neuron function,

as well as the function of all the cells

and all the tissues and organ systems of the body.

If we have sodium, magnesium, and potassium

present in the proper ratios,

all of those cells function properly

and all our bodily systems can be optimized.

If the electrolytes are not present

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our mood is off, hormone systems go off,

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and you’ll get a free Element sample pack

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They’re all delicious.

So again, if you want to try Element,

you can go to slash Huberman.

Today’s episode is also brought to us by Thesis.

Thesis makes what are called nootropics,

which means smart drugs.

Now, to be honest, I am not a fan of the term nootropics.

I don’t believe in smart drugs in the sense that

I don’t believe that there’s any one substance

or collection of substances that can make us smarter.

I do believe based on science, however,

that there are particular neural circuits

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My go-to formula is the clarity formula,

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I’m pleased to announce that the Huberman Lab Podcast

is now partnered with Momentus Supplements.

We partnered with Momentus for several important reasons.

First of all, they ship internationally

because we know that many of you are located

outside of the United States.

Second of all, and perhaps most important,

the quality of their supplements is second to none,

both in terms of purity and precision

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Third, we’ve really emphasized supplements

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you can go to slash Huberman.

There, you’ll see those supplements,

and just keep in mind that we are constantly expanding

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Again, that’s slash Huberman.

Today, we’re going to continue our discussion

about hormones, and we’re going to focus

on how particular hormones influence our energy levels

and our immune system.

Now, last episode, I mentioned at the end

that we were concluding our month on hormones,

but we’ve decided to include this additional episode,

so this would be the fifth episode

in the sequence of episodes about hormones,

because there are two hormones which are vitally important

for a huge number of biological functions

that we will talk about today,

but that are particularly important for energy levels

and your immune system.

This is something that I get asked about a lot.

So rather than skip to the next general topic,

today, we’re going to talk about the hormones cortisol

and epinephrine, also called adrenaline.

You do not have to have heard the previous episodes

on hormones in order to understand and digest the material

from today’s podcast.

If I mention anything related to previous episodes,

I promise to give a little bit of quick background

to get everyone up to speed.

Today, we’re going to talk about the biology of cortisol.

We’re going to talk about the biology of epinephrine.

As always, we’ll talk mechanism,

and there are going to be a lot of tools.

If you’re somebody who struggles with stress

and energy levels and balancing stress and energy levels,

today’s episode is going to be vital for you.

If you’re somebody who has challenges with sleep

or you’re somebody who has challenges

getting your energy level up throughout the day

and getting your energy level down when you want to sleep,

today’s episode is also for you.

And we’re going to talk about the immune system

and how to enhance the function of your immune system.

We’re also going to get into some fun topics

related to learning and memory

and how you can leverage cortisol

and epinephrine in particular in order to learn faster.

We’re going to talk about so-called nootropics,

smart drugs, and how they work,

because there’s several of them

that tap into the epinephrine system

that aren’t often discussed and that you have access to.

We’re going to talk about how caffeine

can actually rewire your brain for better or for worse.

And we’re going to talk about the biology of comfort foods

and why they work so well and what they’re doing.

And in understanding that,

you’ll be able to better understand your food choices

as they relate to short-term and long-term energy.

So we have a lot to cover.

Everything will be timestamped.

I want to just remind people that we caption every episode

in English and in Spanish.

The captions take a day or two to pop up on YouTube.

So if you’re not seeing those within the first couple days,

please be patient with us in order to get captions

that actually read similarly to what I’m saying.

We go through a captioning service.

And so we have them done by experts

and that takes a little bit of additional time.

Meanwhile, if you have any questions as the episode evolves,

please write them down.

Please put them in the comment section.

Please subscribe to the channel if you haven’t already.

And let’s get started talking about

how to increase your energy

and improve and increase your immunity

by leveraging the biology of cortisol and adrenaline.

Before we dive into the biology of increasing energy

and your immune system,

I want to cover three topics

that I promised I would mention from previous episodes.

The first one relates to intermittent fasting.

The second one relates to why your stomach grumbles.

I forgot to mention the biology of that last time.

And the third is a powerful way to increase growth hormone,

which is powerful for increasing metabolism,

fat burning and tissue repair, et cetera,

that doesn’t involve a sauna

or wrapping yourself in plastic bags and going for a jog.

So first, intermittent fasting.

Last episode, I talked a lot about growth hormone

and thyroid hormone.

And I mentioned things like sauna and exercise and sleep

and how they can increase levels of growth hormone

within the healthy ranges.

And why increasing growth hormone can be very beneficial

because it can burn off body fat,

it can improve muscle and general tissue health,

cartilage, et cetera.

And we tend to lose,

or our levels of growth hormone are reduced as we age.

Many people ask me, well, what about fasting?

Everyone’s been promised on the internet

that intermittent fasting leads to these big increases

in growth hormone.

The reason I didn’t mention it

is that I couldn’t find a study

that actually pointed to the underlying mechanism.

I saw lots of claims, lots of podcasts,

lots of degrees behind people’s names,

sometimes biologists, sometimes entirely different fields

talking about this, but very few studies.

And then I found what I would consider the study.

We will link to this study.

Turns out that fasting does increase growth hormone levels

and the way that it does it is fascinating.

I mentioned in a previous podcast

about hunger and timing of meals and timing of hunger,

that when you’re hungry,

you release a hormone in your body called ghrelin,

sometimes actually called ghrelin.

Thanks for all of you ghrelinistas or ghrelinistas

that corrected my pronunciation.

It’s both, ghrelin or ghrelin, either one works.

Ghrelin makes you hungry.

When blood glucose, your blood sugar is low,

ghrelin is secreted and makes you hungry.

And it turns out that ghrelin, this hunger hormone,

actually binds to the receptor in the brain

that normally binds

what’s called growth hormone releasing hormone.

So believe it or not, the hunger hormone

can act like growth hormone releasing hormone

and thereby stimulate growth hormone.

Now, the levels of growth hormone

that fasting promotes through this ghrelin system

are pretty substantial.

It’s about a doubling of growth hormone levels

in the waking state.

So we know that you can release growth hormone in sleep.

Intermittent fasting, it turns out,

can increase growth hormone by binding ghrelin

to the growth hormone releasing hormone receptor,

and it does it also during the daytime.

So yes, indeed, fasting can increase growth hormone,

not to the supra levels

that taking growth hormone would increase it

or that a sauna could increase it,

but it does seem to increase growth hormone.

Later in today’s episode,

we’re going to talk a lot about different patterns

of fasting and eating that can control epinephrine.

And so we will return to specifics about how long a fast.

Do you need to fast for two or three days or 23 hours?

Fortunately, for people like me who love to eat,

that’s not the case.

So we’ll talk specific fasting protocols

later in the episode.

We also said we were going to talk about tummy grumble.

When your stomach growls,

it is not because of fluid sifting around in there.

A lot of people think, oh, you know,

it’s fluid sifting around.

Turns out that your stomach has smooth muscle

that lines its sides.

And when you eat something or you don’t,

every once in a while,

your stomach cinches off at the two ends,

like a bag with a hose on either end,

because that’s essentially what your digestive system is.

And if there’s nothing in there,

what happens is the muscles

that line the sides of your stomach,

they kind of extend around the stomach in these cables.

Those are always there.

And if you have food in your stomach,

what they do is they churn your stomach.

They literally turn the muscles of your stomach

like a tumbler to help break up the food

that presumably you didn’t chew well enough

because you were eating too fast.

When you don’t have any food in your stomach,

that churning continues and that contraction of the muscle

and the turning, literally turning over of your muscles,

they don’t flip over completely,

but the turning over the muscles,

that’s what causes the stomach growling.

If you don’t want to be the person in the meeting

or sitting there in a quiet theater

whose stomach is growling, chew your food better.

That’s the simple solution.

And last episode, I talked a lot about how sauna,

controlled safe hyperthermia,

can cause huge increases in growth hormone release,

anywhere from 300 to 500,

even 1,600% increases in growth hormone release,

really staggeringly high increases.

I point out that many people don’t have saunas

in their yard or in their homes,

and they would go through some other measures

to increase safely their body heat,

creating a steam room in their bathroom

or jogging with extra sweats on, this kind of thing.

Many of you asked about hot baths.

Hot baths will increase growth hormone, excuse me.

However, the temperatures that you need

in order to increase growth hormone

are high enough that you run the risk of burn.

And so I really can’t make any recommendations

about hot baths, but if you can tolerate a nice hot bath,

you are going to get some growth hormone release.

However, the sauna has this advantage

of you being able to enter 175 degree

or 200 degree environment,

provided you’re not pregnant,

you’re not a young child, et cetera.

You can do that safely.

And getting big increases in growth hormone,

the hot bath will lead to lesser increases

in growth hormone.

We’re going to talk a lot about temperature regulation

in a future episode, but as always,

if you’re ever going to start playing with hyperthermia

or hypothermia, cold baths, ice baths, hot showers,

hot baths that are beyond the kind of norm

of what’s comfortable, you have to be extremely careful

and please consult a doctor.

I think it’s fair to say that most people

would like to have a lot of energy during the day,

if you work during the day,

and they’d like their energy to taper off at night.

And I think it’s fair to say that most people

don’t enjoy being sick.

Nobody wants to get sick.

In other words, you want to have energy

and you want your immune system to function well,

to ward off infections of various kinds,

bacterial infections, viral infections, et cetera.

And it turns out that the two hormones

that dominate those processes of having enough energy

and having a healthy immune system

are cortisol and epinephrine.

Epinephrine is the same thing as adrenaline.

In the body, we tend to call adrenaline adrenaline,

and in the brain, we tend to call adrenaline epinephrine.

And I’m sorry for that, I didn’t create this naming system.

And the story behind it is uninteresting

and not worth our time.

I will use the words adrenaline and epinephrine

interchangeably today.

Cortisol is cortisol.

And I just want to cover a little bit

about what cortisol and epinephrine are,

where they are released in the body and brain.

Because if you can understand that,

you will understand better how to control them.

First of all, cortisol is a steroid hormone,

much like estrogen and testosterone,

in that it is derived from cholesterol.

Now that could be cholesterol that you eat.

It could be cholesterol that’s produced by the liver.

As many of you probably know,

the relationship between dietary cholesterol,

the fats that you eat,

and blood cholesterol and liver cholesterol

is a very controversial one.

It’s a barbed wire topic.

There are people that claim that dietary cholesterol

has zero impact on circulating cholesterol

coming from the liver.

There are people who argue the exact opposite,

both with good data in hand, I would say.

There are some problems for the idea

that all your cholesterol levels

are determined by dietary intake,

namely that anorexics often have very high levels

of cholesterol that their liver produces,

even though they are eating very little

and sometimes not eating at all.

So understand that cholesterol is a precursor molecule,

meaning it’s the substrate from which a lot of things

like testosterone and estrogen are made.

Please also understand that cholesterol

can be made into estrogen or testosterone or cortisol,

and that cortisol is sort of the competitive partner

to estrogen and testosterone.

What this means is no matter how much cholesterol

you’re eating or you produce,

whether or not it’s low or it’s high,

if you are stressed, more of that cholesterol

is going to be devoted toward creating cortisol,

which is indeed a stress hormone.

However, the word stress shouldn’t stress you out

because you need cortisol.

Cortisol is vital.

You don’t want your cortisol levels to be too low.

It’s very important for immune system function,

for memory, for not getting depressed.

You just don’t want your cortisol levels to be too high,

and you don’t want them to be elevated

even to normal levels at the wrong time of day.

So we’re going to talk about how to control the timing

and level of your cortisol.

Epinephrine or adrenaline has also been demonized a bit.

We think of it as this stress hormone,

this thing that makes us anxious, fight or flight.

You know, we used to get chased by lions

and tigers and bears, and now we don’t,

and it’s this ancient hangover.

That’s all wrong.

The fact of the matter is that epinephrine

is your best friend when it comes to your immunity,

when it comes to protecting you from infection.

And we’re going to talk about why.

And epinephrine, adrenaline, is your best friend

when it comes to remembering things

and learning and activating neuroplasticity.

We’re going to talk about that as well.

Once again, it’s a question of how much and how long

and the specific timing of release

of cortisol and epinephrine,

as opposed to cortisol and adrenaline being good or bad.

They’re terrific when they’re regulated.

They are terrible when they’re misregulated.

And we will give you lots of tools to regulate them better.

Cortisol biology 101 in less than two minutes.

Your brain makes what we call releasing hormones.

And in this case, there’s corticotropin releasing hormone.

CRH is made by neurons in your brain.

It causes the pituitary, this gland that sits

about an inch in front of the roof of your mouth

and the base of your brain,

to release ACTH.

ACTH then goes and causes your adrenals,

which sit above your kidneys and your lower back,

to release cortisol, a so-called stress hormone.

But I would like you to think about cortisol

not as a stress hormone, but as a hormone of energy.

It produces a situation in the brain and body

whereby you want to move

and whereby you don’t want to rest

and whereby you don’t want to eat, at least at first.

Epinephrine or adrenaline 101 in less than two minutes.

When you sense a stressor with your mind

or your body senses a stressor, excuse me,

from a wound or something of that sort,

a signal is sent to neurons

that are in the middle of your body.

They’re called the sympathetic chain ganglia.

The name doesn’t necessarily matter.

They release norepinephrine very quickly.

It’s almost like a sprinkler system

that just hoses your body with epinephrine.

That will increase heart rate,

will increase breathing rate.

In some cases, it will constrict your blood vessels.

It will also increase the size of vessels and arteries

that are giving blood flow to your vital organs.

This is why your extremities get cold when you’re stressed

and your heart is beating faster.

More of that energy is being devoted toward your core.

You also release adrenaline from your adrenals in, again,

riding atop your kidneys.

Those are a second system

whereby your system gets flooded with adrenaline in pulses.

So you can get one pulse, you can get 10 pulses.

We’ll talk about how to regulate the number of pulses.

And you release it from an area of your brain

called locus coeruleus,

and that creates alertness in your brain.

If you want to learn more about the stress response

and all the details of that,

including some protocols of how to regulate stress,

please see our episode about stress.

I go into a lot of detail there.

I will touch on some of the same themes today,

but I really want to cover energy and the immune system.

And if you’re very much interested in stress per se

and stress regulation, please see the episode on stress.

Okay, so we have cortisol and we have epinephrine,

and their net effect is to increase energy.

So first of all, I want to give you a tool

that will help you regulate cortisol

and can also help stave off

certain patterns of mental illness.

Now, of course, it’s not going to cure mental illness

on its own, but it can support healthy state of mind

and can help reduce unhealthy states of mind,

including depression.

So the first tool is to make sure

that your highest levels of cortisol

are first thing in the morning when you wake up.

One way or another, every 24 hours,

you will get an increase in cortisol.

That is non-negotiable, that is written into your genome.

That increase in cortisol is there to wake you up

and to make you alert.

It’s to stimulate movement from being asleep,

presumably horizontal, to getting up

and starting to move about your day.

And I’ve said it before, but I will say it again,

the best way to stimulate that increase in cortisol

at the appropriate time is that very soon after waking,

within 30 minutes or so after waking,

get outside, view some sunlight.

Even if it’s overcast, get outside, view some sunlight,

no sunglasses, never look at any light so bright

that it could damage your eyes,

but do that for two to 10 minutes.

If it’s very bright, two minutes,

if it’s not so bright, 10 minutes.

Do that because in the early part of the day,

you have the opportunity to time that cortisol release

to the early part of the day, which will improve,

this has been backed by peer-reviewed studies,

it will improve your focus,

it will improve your energy levels,

and it will improve your learning throughout the day.

It will also prevent a late shift in cortisol increase.

And late shifted cortisol,

meaning cortisol that increases around eight or 9 p.m.,

is a signature feature of many depressive disorders,

including major depression, anxiety,

and that of course correlates

with things like insomnia, et cetera.

So that’s a key tool,

and I don’t know how many of you are already doing that,

but it is vital to do.

Now, I mentioned sunlight even on cloudy days,

and there are specific reasons for that.

So I want to just briefly cover the data,

because in the episodes on sleep,

I talked about brightness of light

in regulating cortisol and sleep,

and I talked about how to measure lux, brightness,

but I was not specific enough, I realized,

based on the questions that I’ve received

since that episode.

So here’s how it works.

Going outside and getting some sunlight

requires that I also tell you how long

and under what conditions.

I’ve said, looking through a window is not as good,

it takes 50 times longer to get as much light,

et cetera, et cetera.

Many, many questions have told me

that I’m not being specific enough.

So I’m going to give you the data,

and from the data, you will understand

exactly how long you need to do this each day.

On a sunny day, so no cloud cover,

provided that the sun is not yet overhead,

it’s somewhere low in the sky,

could have just crossed the horizon,

or if you wake up a little bit later,

it could be somewhat low in the sky.

Basically, the intensity of light, the brightness,

is somewhere around 100,000 lux.

Lux is just a measurement of brightness.

If you want to download the app Light Meter,

that is a free app that will allow you to do that,

you can hold your finger down on the little button there,

and you can move it around,

and it will continuously give you a lux readout.

It’s not perfect, it’s not exact,

but it’s pretty good, and it is zero cost.

I have no relationship to Light Meter, the company.

On a cloudy day, it’s about 10,000 lux, okay?

So tenfold reduction.

But bright artificial light, very bright artificial light,

is somewhere around 1,000 lux.

And ordinary room light is somewhere around 100 to 200 lux.

And it has to do with how much light scatter there is.

So even if you have a very bright bulb

sitting right next to you, that’s not going to do the job.

Your phone will not do the job, not early in the day.

To get the cortisol released at the appropriate time,

you need to get outside.

So let’s just set a couple general parameters.

If it’s bright outside and no cloud cover,

the light can be indirect.

You don’t have to be staring into the sun.

Please don’t damage your eyes.

We can’t regenerate those neurons yet

and restore vision that’s lost.

But if you have to blink, that means it’s too bright.

It’s fine to blink, of course.

Please do if you need to.

Get outside for 10 minutes.

Or five minutes should suffice,

but 10 minutes is sure to suffice.

If it’s a cloudy day, dense overcast,

you’re probably going to need about 30 minutes.

If it’s light cloud, broken cloud cover,

it’s probably going to be somewhere

between 10 and 20 minutes.

And if you can’t get outside or you’re on an airplane

and it’s bright overhead artificial lights

or ordinary room lights,

it’s going to take you about six hours of light.

And by time you reach the middle

of your sort of wakeful period, it’s too late.

You won’t be able to shift your clock

and your cortisol will start drifting later and later.

This is why it’s vital to get this light

on a regular basis to get that cortisol released

early in the day.

That sets you up for optimal levels of energy.

It sets you up for great sleep,

but today’s not really about sleep.

It’s more about energy.

That cortisol pulse and the stress

that you might feel early in the day

from having a little bit extra energy,

that is the energy that you want in order to move about

and learn and do various things.

That is a healthy level of energy.

So please try and get that sunlight

if it’s within your protocols to do that

and try and get sufficient sunlight

first thing in the morning, again, within the first hour.

That’s the best way to make sure

that you time your cortisol appropriately.

Now, throughout the day,

you’re going to experience different things.

Most of you are not spending your entire day

trying to optimize your health.

Some of you might be, but most of you have jobs

and you have families and you have commitments.

Life enters the picture and provides you stressors.

And those stressors, whatever they may happen to be,

a difficult coworker,

some disappointment about something,

you didn’t get the raise you expected

or you didn’t get the vacation that you expected,

those will cause increases in cortisol and epinephrine.

This is important to understand.

You don’t have the luxury of just having

this morning cortisol and then having it taper off.

You want that major cortisol early in the day,

but then you can expect, you should expect,

increases in cortisol and adrenaline throughout the day

based on events that are unpleasant to you.

So for me, the events that are most unpleasant to me

are things like traffic,

emails that ask me to fill out a form

for which I can’t find the link.

These kinds of things stress me out.

I’m a human being.

I don’t lose my cool over them,

but I can feel my level of alertness

and kind of frustration increase.

The normal kind of things that go with stress

tense up a little bit.

The key is these blips in cortisol and epinephrine

need to be brief.

You can’t have them so often or lasting so long

that you are in a state of chronic cortisol elevation

or chronic epinephrine elevation.

This system of stress was designed

to increase your alertness and mobilize you towards things,

get you frustrated and provide the opportunity

to change behavior.

That’s what they were designed to do.

So if you find yourself getting stressed

and staying stressed,

there are great tools that we provide in the stress episode

that relate to things like the double inhale, exhale,

the so-called physiological sigh.

You can incorporate an NSDR,

a non-sleep deep rest protocol, et cetera.

But understand that the energy

that you experience during stress,

that sudden increase in alertness and attention

that comes from seeing something difficult,

that is a healthy hormonal system

and neural system that’s working.

And the reason it works is that cortisol,

when it’s released into the bloodstream,

it actually can bind to receptors in the brain.

It can bind receptors in the amygdala,

fear centers and threat detection centers,

but also areas of the brain that are involved

in learning and memory and neuroplasticity.

And this is why I say that neuroplasticity,

the brain’s ability to change itself

in response to experience

is first stimulated by attention and focus

and often a low-level state of agitation.

So understand that,

and you won’t be quite so troubled

about the little stress increases

that you experience throughout the day.

Now, there are ways to leverage stress,

epinephrine and cortisol in ways that serve you

and to do it in a deliberate way.

There are also ways to do that

that increase your level of stress threshold,

meaning they make it less likely

that epinephrine and cortisol will be released.

So I want to talk about the science of those practices,

because I get asked about these practices a lot.

Things like Wim Hof breathing,

which is also called TUMO breathing,

things like ice baths,

things like high-intensity interval training.

All of those things have utility.

The question is how you use them and how often you use them.

Those tools, just like stress from a life event,

can either enhance your immunity or deplete it.

That’s right.

Those same practices of ice baths, TUMO breathing,

high-intensity interval training or training of any kind

can deplete your immune system or it can improve them.

Excuse me, they can improve it,

meaning they can improve your immune system.

The key is how often you use them and when.

And so I want to review that now

in light of the scientific literature,

because in doing that,

you can build practices into your daily

or maybe every other day routine

that can really help buffer you

against unhealthy levels of cortisol and epinephrine,

meaning cortisol increases that are much too great

or that last much too long.

Epinephrine increases that are much too great

or that last much too long.

And of course, we’ll talk about all the negatives

that go along with having too much cortisol,

too much epinephrine for too long,

but you hear about those a lot.

You hear about Cushing syndrome.

You hear about abdominal fat accumulation.

You hear about sleep disturbances.

I want to arm you with the tools first,

and then we can talk about the dark side

and all the things that hopefully

you’ll be able to avoid entirely

or that you can get yourself out of

once you have the tools in hand.

Let’s say somebody tells you something very troubling,

or you look at your phone and you see a text message

that’s really upsetting to you.

That will cause an immediate increase

in epinephrine, adrenaline, in your brain and body.

And chances are it’s going to increase

your levels of cortisol as well.

Let’s say you get into an ice bath or a cold shower.

Even if you love the cold or if you hate the cold,

that will cause an equivalent increase

in epinephrine and cortisol.

We don’t know the exact levels,

but it’s probably about the same.

Let’s say you go out for high-intensity interval training.

You decide you’re going to run some sprints.

You do some repeats,

or you’re going to do some weightlifting in the gym,

and you love lifting weights in the gym.

Maybe you like the powerlifting thing,

or you decide that you want to do some hot yoga,

or something that you really enjoy or you hate,

you’re going to increase

your epinephrine and cortisol levels.

There’s simply no way around this.

Let’s say you decide to sit down

and you’re going to do some deep breathing.

We all hear about the benefits of deep breathing.

So inhale, exhale, inhale, exhale.

You’re going to get big increases

in epinephrine and cortisol.

The data from multiple studies support this.

All of those are stressors, in air quotes.

Now, there is a way

that you can cognitively reframe what those are.

You can tell yourself,

I love high-intensity interval training,

or I love weight training,

or I personally love exercise.

I’m not crazy about the cold.

I do some cold exposure stuff now and again,

and we’re going to talk a lot about how to do that

in the optimal way in an upcoming episode.

But getting into the cold doesn’t feel good to me.

I tell myself it’s good for me,

and I enjoy it at some point,

usually when I’m getting out.

All of those increase epinephrine,

and guess what?

They increase your levels of energy and alertness.

So if you’re somebody who struggles

with energy and alertness,

it can be beneficial,

provided you get clearance from your doctor,

to have some sort of protocol built into your day

where you deliberately increase your levels of epinephrine

and your levels of cortisol.

And I want to put the emphasis on deliberately.

So how would you do that?

Well, it’s quite easy to turn the shower cold

and get into that.

That will wake you up,

and it literally wakes you up

because of increases in epinephrine.

You can do deep breathing of the sort

where you inhale and exhale repeatedly 25 or 30 times,

maybe hold your breath for a few seconds on an exhale,

and then repeat, so-called Wim Hof or Tummo type breathing.

Lots of adrenaline is released into your system

when you do that.

You will have more energy afterwards.

So it’s really important to understand

that the body doesn’t distinguish

between a troubling text message, ice,

Tummo breathing, or high-intensity interval training,

or any other kind of exercise.

It’s all stress.

Cognitively reframing that and telling yourself,

I like this, I enjoy it,

is not going to change the way

that that molecule impacts your body and brain.

I sort of chuckle because people would love to tell you

that all you have to do is say, oh, this is good for me.

No, what it does to tell yourself that it’s good for you

or that you enjoy it is that it liberates other molecules

like dopamine and serotonin

that help buffer the epinephrine response.

Now, the way that it does that,

I’ve talked about previous episode,

but I’ll just mention that dopamine

is the precursor to epinephrine.

Epinephrine, adrenaline, is made from dopamine, okay?

Cortisol is made from cholesterol.

Epinephrine is made from dopamine.

And that’s why if you tell yourself

you’re enjoying something,

and because dopamine is so subjective,

that you can, in some ways,

as long as you’re not completely lying to yourself,

you can get more epinephrine,

you get more mileage or more ability

to push through something,

and you can sort of reframe it.

But it’s not really cognitive reframing.

The cognitive part is the trigger,

but it’s a chemical substance

that’s actually occurring there.

It’s dopamine giving you more epinephrine,

a bigger amplitude epinephrine release,

and it gives you some sense of control.

So here’s a protocol that anyone can use

if you want to increase levels of energy,

if you suffer from low energy during the daytime,

or whenever it is that you’d like to be alert.

Pick a practice that you can do fairly consistently,

maybe every day,

but maybe every third day or every fourth day.

Maybe it’s an ice bath or a cold bath.

Maybe it’s a cold shower.

Maybe it’s the cyclic inhale, exhale,

breathing protocol I described.

If that wasn’t clear, and people always ask for a demo,

I’m not going to do the whole thing right now,

but I’m willing to do a few rounds of this,

or a few cycles, I should say.

So it’s inhale.

I would do that more deeply,

more like you do that 25, 30 times repeatedly.

You will start to feel warm.

People in the yoga community,

they say you’re generating heat.

You’re not generating heat, releasing adrenaline.

Inhale, exhale, inhale, exhale 25 or 30 times.

You will feel agitated and stressed.

That’s because you’re releasing adrenaline in your body,

and that’s because you’re releasing norepinephrine

in your brain, and you’ll be more alert.

Then you can follow that 25 or 30 breath cycles

with an exhale hold,

and hold your breath for 15 to 30 seconds.

Always, always, always do this on dry land,

never while driving, operating heavy machinery,

all the standard safety protocols, never near water, please.

People have passed out and died doing this

with breath holds in water.

There are several deaths associated with it.

On land, it’s probably safer.

Clear it with your doctor, but 25, 30 breaths, exhale, hold.

25, 30 breaths again, exhale, hold.

25, 30 breaths again, exhale, hold.

And then if you like, you can do an inhale and hold,

if that’s within your margins of safety.

So if all these protocols,

all these activities are just equivalent,

they’re just stress, then how do we make them good for us?

How do we actually benefit from them?

Now, of course, the cold itself

can have some health-promoting effects.

It can increase brown fat thermogenesis and metabolism,

high-intensity interval training

or other forms of exercise,

of course, has cardiovascular effects

that can be good for us, as does weight training, et cetera.

But what we’re talking about here

are ways to increase energy and to teach our brain and body

to teach ourselves how to regulate the stress response.

So in addition to the benefits of the actual practices,

what we’re talking about is building a system

so that when you experience increases

in epinephrine and cortisol from life events,

you’re able to better buffer those.

And we are also talking about ways

that you can increase energy overall,

because that’s what today’s episode is all about,

energy and the immune system.

And indeed, we will talk about

how you can actually leverage specific protocols

to increase your immune system on demand.

There’s great scientific data to support

that one can do that.

So there’s a biological mechanism

that’s very important if you want to do those things,

increase energy and your immune system on demand,

learn to buffer stress on demand in real time.

And it means taking these protocols,

these practices, whether or not it’s cold water

or ice bath or exercise or any of those,

and making one small but very powerful adjustment

in how you perform them.

But in order to make that adjustment,

I can’t just tell you the adjustment.

I have to tell you the mechanism

so that you know if you’re doing it correctly or not.

This is really a case where if you can understand

a little bit of mechanism,

you will be far better off than just adopting protocols.

So if you take away nothing else from this episode,

except what I’m about to tell you,

please take away the information I’m about to tell you.

Cortisol, as I mentioned, is released from the adrenals

and it can bind to receptors.

It can have action both in the body and in the brain.

In fact, it can bind the so-called

threat detection center in the brain,

or one of them, which is the amygdala,

also called the fear center.

It can do that because cortisol

can cross the blood-brain barrier.

It can be released in the body

and cross this biological barrier.

It’s like a fence that keeps things out of the brain,

but cortisol has passing rights.

It can go through.

Epinephrine cannot.

Epinephrine is polarized.

The shape of it is such that it can’t make it

through the blood-brain barrier.

That’s one of the reasons why it’s released

both from the adrenals in your body

and released from this brainstem area,

the locus coeruleus in your brain.

That’s a powerful thing because what it means

is that the body can enter states of readiness

and alertness while the mind remains calm.

That is biologically possible.

It’s not just a psychological trick.

And there are ways that one can do that.

So I’m presuming at this point

that you’re getting your morning light

to time your cortisol increase.

I’m presuming that you want more energy

or that you want to increase your immune system’s function

and its ability to combat infections of various kinds.

And what I’m suggesting is that you pick from the palette

of exercises that are out there

or tools that are out there to increase epinephrine.

There are a lot of ways to do that.

You can do that, as I mentioned,

through cold water, through exercise.

You can even do that by having confrontations

with other people.

At a biological level, it is identical.

So if you like to go online and place the kind of comments

that will read the kinds of things

or look at the kinds of things that agitate you,

you can, if you like, look at that as an opportunity.

I’m not suggesting you do that.

I’d like to see people taking care of themselves

and each other in much less destructive ways, frankly.

But the prerequisite here is getting an increase

in adrenaline released from the body.

Now, the simplest way to describe how to do that

would be in the context of cold water

or a breathing protocol,

because then I don’t have to deal

with the unknown life circumstances that get you triggered,

or I could tell you what gets me triggered,

but I’m not going to.

So let’s presume cold water.

So let’s say you decide you’re going to take a cold shower.

You get into the cold shower, and if it’s cold enough,

that will be stressful.

You will experience an increase in epinephrine.

It will increase your alertness.

Now, you’re using this as a practice,

as a tool to build, you could call it resilience,

but the ability to stay calm in the mind

while being stressed in the body,

epinephrine’s in the body.

And you do that by subjectively trying to calm yourself.

Now, you can do that by telling yourself it’s good for you,

by emphasizing your exhales,

anything that you can do to try and stay calm

despite the fact that you are

in a heightened state of alertness.

You do this with exercise, you could do this with music,

pretty much anything that will give you

a really heightened state of alertness

offers you the opportunity to try and stay calm in the mind.

What you’re trying to do at a mechanistic level

is to have adrenaline released from the adrenals,

but not have adrenaline epinephrine released

from the brainstem to the same degree.

So you’re not just trying to buffer this.

You’re not trying to say, oh, this is good for me.

This is good for me, I’m going to grind this out.

You’re not trying to grind it out.

You’re trying to move through this calmly

while maintaining alertness.

You’re not trying to zone out necessarily,

although maybe that helps.

You’re not trying to distract yourself.

What you’re trying to do is shift cognitively

your relationship to the somatic,

to the body stress response.

Now, I’m sure some of you out there are shouting,

yeah, that’s exactly like whatever, whatever, whatever.

I agree, this is in many ways

a self-directed kind of stress inoculation,

but we’re not talking about this as stress inoculation.

We’re talking about this as a way

to increase energy and focus.

And the reason is that epinephrine,

when released in the body,

has a profound effect on the immune system.

And when released in the brain has a profound effect

on the ability to learn and remember information

and to be alert.

And so we’re talking about splitting the location,

separating the location from which

you have epinephrine adrenaline released, okay?

So let’s say you are doing this practice simply to wake up.

Okay, cold shower, we’ll do that.

Exercise, we’ll do that.

The ability to stay calm in mind

while having heightened levels of adrenaline

and presumably cortisol as well in the body,

but the cortisol is going to circulate everywhere.

We’ll talk a little bit about cortisol more in a moment.

You could do that through some self-soothing, calming way.

That’s going to be highly individual.

You do it by telling yourself you enjoy it, et cetera.

But what you need to understand

is that in the immediate period following that practice,

your system, your entire brain and body are different.

Your body is actually primed to resist infection

when you have high levels of epinephrine in it

for short periods of time.

So the scientific study that explored

how increasing adrenaline in the body

can improve immune resistance

is grounded in a well-known phenomenon

that increases in stress actually protect you

against infection in the short term.

So I want to look at the classic data first,

describe what was done,

and then I want to talk about the more recent study

which is immediately actionable.

There are classic set of studies

that are really based mainly on the work

of somebody named Bruce McEwen

who is at the Rockefeller University in New York.

Bruce passed away a few years ago,

but he had many decades of incredibly impactful work

under his belt when he did.

The work that I’m going to talk about next

has been done in humans and has been done in animals

and has really explored how inducing stress

can enhance the function of the immune system

in the short term.

And when I mean short term, I mean about one to four days.

I’m not going to go through all the details of the study,

but essentially what they were doing

was exposing subjects to some sort of infection,

either bacterial or viral infection, and inducing stress.

Sounds like a double whammy, right?

You’d think that maybe getting a little electric shock

or cold water exposure

or something to increase your levels of stress

and adrenaline would just make

the effects of the infection worse,

but no, quite the opposite.

Brief bouts of stress,

which now you should be thinking about

in terms of cortisol and epinephrine release,

were actually able to increase immune system function.

Now, that shouldn’t surprise you

if you understand a little bit

about how epinephrine works in the body and in the brain.

It essentially is the signal

by which the nervous system can inform immune organs,

things like the spleen and other organs

that make killer cells of various kinds,

B cells and T cells,

to go and combat infections, bacteria and viruses.

How else would your immune system know

that there was an infection?

Your immune system can recognize foreign invaders,

but the nervous system provides the signal,

the sort of alarm signal that liberates the killer cells,

that tells them there’s a problem

and to go seek out the problem, so to speak.

So the duration here is really important

because if stress stayed too high for too long,

then yes, indeed, stress can hinder the immune response,

but for a period of about one to four days,

it actually can protect you

by way of increasing the immune response.

Now, I can say with certainty

that that effect is governed by epinephrine,

adrenaline released from the adrenals

and not from the brain

because they actually explored

whether or not the effect exists

in the presence of what’s called an adrenalectomy

or removing the adrenals.

So I should just say,

without the adrenals, you don’t get the effect.

So we know that that effect

comes from adrenaline in the body.

What does that mean for you?

That means if you want to increase your immune system

in the short term,

you want to increase your epinephrine in the short term.

That’s why short bouts of very intense exercise,

probably no more than an hour per day,

provided you’re doing everything else right,

sleeping and nutrition, et cetera,

maybe even shorter bouts of intense exercise

or exposure to cold water

or the cyclic breathing that I talked about before,

because they increase epinephrine,

they will bolster the immune system.

And we all hear these reports every once in a while,

seems to be the thing that every once in a while,

there’ll be an article about how coffee

can improve your immune system or something like that.

Indeed, caffeine can increase epinephrine

and dopamine to some extent,

but most people are drinking it chronically.

So its effects are probably due to increases in epinephrine

and probably whether or not something like coffee

or other forms of caffeine can improve

or degrade your immune system

will probably depend on whether or not

you’re using it in a way that it increases your adrenaline

as a spike that happens rarely,

once every two or three months,

let’s say you have an infection coming on.

Yes, indeed, what these data probably mean

is that drinking some hot caffeinated tea

or some hot coffee even,

provided you don’t get dehydrated from it

because you’re also drinking some water

can probably improve your immune system function

by way of increasing adrenaline release.

But so can the breathing, so can cold exposure,

so can exercise.

The mechanism here is what’s key.

And I keep saying that because what it means

is that you don’t actually have to know

the specific protocol.

I’m not trying to say do this particular protocol.

You have to figure out,

and it should be easy to figure out

what short-term adrenaline increasing behavior

you’re willing to do on a regular basis every day

or two or three times a week.

Now you could say, well, I’m not sick.

Should I be doing these things often?

I would say two or three times a week at a minimum

if your goal is to keep your immune system tuned up

and you are in the presence of a lot of children,

for instance, which carry a lot of bugs

because their immune system isn’t developed,

or you work in a healthcare setting,

or you’re simply somebody who’s prone to get sick.

I can just say anecdotally,

I guess someone now calls this anic data,

which I don’t like that phrase

because it’s sort of,

I don’t want anecdotal data to ever be misunderstood

as anything but anecdotal data.

Anecdotally, I can say that I’ve had instances

where I’ve felt a throat tickle coming on

or some sinus infection.

I will do the cyclic breathing that I described before,

25, 30 breaths, exhale, hold,

25, 30 breaths, exhale, hold,

25, 30 breaths, exhale, hold,

and then big inhale, hold.

And most times I didn’t get full-blown sick,

but I also take other precautionary measures

to get sleep, et cetera.

Whether or not it was causal

or whether or not it’s just correlated, I don’t know.

However, there’s a human study

that I definitely want to point out to you

because it was published more recently

than the McEwen work.

It was published in the Proceedings

of the National Academy of Sciences for the USA

because there are Proceedings

of the National Academy of Sciences

for many other countries as well.

The title of the paper is

A Voluntary Activation of the Sympathetic Nervous System.

That’s the system that causes fight or flight,

and AKA stress, and causes release of adrenaline.

An attenuation of the innate immune response in humans.

This is Cox, K-O-X et al., P-N-A-S,

Proceedings of the National Academy of Sciences, 2014.

And they incorporate the ever-famous Wim Hof breathing.

Wim Hof breathing is much like the breathing protocol

that I’ve described several times now in this podcast.

It’s also called Tummo breathing.

Other people from other cultures and communities

have called it other things.

The naming really isn’t important,

although I do think Wim is a pioneer

in trying to bring these practices

to the general public more broadly,

and was involved in this study.

The study was done in the Netherlands.

It was communicated by Dr. Thomas Horvath at Yale.

I mention all that.

Horvath is a terrific scientist.

I’m familiar with his work over many years.

Here’s what they did.

They injected people with E. coli,

and they had groups that either did

the sorts of breathing I’ve been describing,

that increased adrenaline release,

although I should say,

I don’t think you need that breathing

to get adrenaline release.

You could do it with cold exposure.

You could do it with other things,

high-intensity interval training as well.

And what they found was that the response to the E. coli

was quite different in the people that had a protocol,

in this case, breathing, to increase adrenaline.

So this is a remarkable study

because what they found was that the fever,

the vomiting, all the negative effects of E. coli,

many of them, and in some cases, all of them,

were greatly attenuated

by way of engaging the adrenaline system,

in this case, using breathing.

They looked at inflammatory cytokines,

things like IL-6,

which I’ve mentioned many times on this podcast,

the sort of classic inflammatory cytokine were reduced.

Things like IL-10, which are anti-inflammatory,

were increased.

There were some inflammatory cytokines that were increased.

What’s the point here?

The point is you can control your immune system

by finding a way that you can increase adrenaline.

And this runs counter to what we always hear,

which is don’t get too stressed or you will get sick.

Learn to control adrenaline.

Turn it on and turn it off.

Learn to control cortisol.

Turn it on with light in the morning,

try and turn it off.

And then when it spikes because of life events,

learn to turn it off.

Learning to turn on and off adrenaline, aka epinephrine,

and learning to turn on and off cortisol

affords you the ability to turn on energy

and focus in your immune system.

That’s the most important point from today’s podcast.

And understanding that it doesn’t matter

what protocol you use.

Maybe it’s a cup of coffee

and running up a hill five or six times.

That will improve your immune system function

if you get adrenaline in your system.

You can use an ice bath.

You can use a cold bath.

It really doesn’t matter.

You can get into an argument,

but I’m not suggesting you do that.

It really doesn’t matter.

What’s important is that you’re able

to then shut off that response.

And there are ways to do that we will talk about,

but I want to talk about some of the other benefits

of epinephrine and cortisol

that occur because of their actions on the brain,

because these are many and they are powerful

and they relate to energy, but also the ability to learn.

If I haven’t already convinced you

that seeing light early in the day

is good for timing your cortisol,

I should also mention that another hormone

that I discussed last episode, which is thyroid hormone,

and it’s critical for setting your level of metabolism,

is controlled in part by these circadian mechanisms

and cortisol itself.

The short takeaway on this is that

if you get your cortisol release early in the day,

it will increase your energy throughout the day.

It will also time your thyroid release properly.

So there’s yet another reason why you would want

to get that light exposure early in the day.

For me, that’s a non-negotiable practice.

If I’m on a plane, I’ll try and get it any way I can.

I’m not shining flashlights in my eyes yet,

but I really try hard to get that light exposure

from sunlight early in the day without fail.

And the thyroid increase has to do with the fact

that your circadian clock itself is regulated by cortisol

and the circadian clock times the release

of thyroid hormone.

I don’t want to go too far off in that direction,

but there are a number of studies,

Calsbeek et al, K-A-L-S-B-E-E-K et al,

2012, if you want to look it up on PubMed,

is a great one that describes how cortisol secretion

begins to rise during sleep and peaks shortly after waking

or immediately before.

And that times a set of neurons in the circadian clock

that then trigger the release of the releasing

and stimulating hormones for thyroid.

So a really important mechanism.

And thyroid will also tend to correlate with energy,

but mostly metabolism.

Very important to have thyroid in check.

Now let’s talk about epinephrine and cortisol

and learning and memory.

Everyone has a story about being so stressed

they couldn’t remember something.

You know, sit down to an exam.

I actually had this happen once,

sat down to an exam and just blanked, just blanked.

It only happened once.

I don’t know what happened.

I don’t think it was sleep deprivation,

but I just completely blanked.

And it was very hard for me to pull myself

out of that ditch.

I did manage to do it, but it was a scary experience.

So I think most people think about stress

and an inability to perform.

However, most of the time increases in epinephrine,

provided they are not through the roof,

lead to improved performance.

Now this has been shown over and over again

on memory tests, on learning new information,

on physical performance,

that when blood levels of epinephrine are low,

you don’t perform very well.

When blood levels of epinephrine are very high,

up to about 1,500 to 1,700 picograms per mil,

if anyone’s out there who’s actually measuring this stuff,

but I doubt you are, performance goes way up.

Performance gets better when you are alert

and when you’re a little bit stressed.

Absolutely shown again and again and again.

If you get too stressed, it’s the mental side,

it’s the epinephrine in the brain that causes people

to either focus on their somatic response too much,

like they feel like they’re sweating

and they’re focused on their bodily response

and they’re not focused on what it is they’re trying to do

or say or perform, et cetera, or learn.

But epinephrine is a nootropic,

it is a smart drug that we all make internally.

And cortisol is as well.

Now here’s the twist.

That does not mean that you want epinephrine high

during the exam necessarily.

Memory and learning and performance are actually favored,

they are enhanced by epinephrine increases

immediately after learning.

And that’s something that’s rarely discussed,

the timing is vital.

So if you learn some information, you have a conversation,

you’re trying to learn a new language, a new motor skill,

whatever it is that you’re trying to learn,

the increase in epinephrine that occurs just afterward

is what’s going to consolidate the information.

It’s going to ensure that the proper circuits

and mechanisms in the brain for neuroplasticity

are engaged during sleep later that night or the next night,

which is when the real rewiring occurs.

And you might say, that’s crazy, why would that happen?

Well, we have to remember,

none of these mechanisms evolved

for us to do what we want

and learn what we want necessarily,

although they will allow us to do that.

We’ve experienced this before.

We might’ve gotten up, gone outside, get in our car,

drive to work or to somebody’s house,

you’re not thinking about much at all,

and then all of a sudden you see an accident on the road.

Your alertness is primed

if it happens to be a particularly gory accident,

there’s going to be a lot of sensory information there,

all of a sudden adrenaline, epinephrine

is released into your brain and body.

Guess what?

Not only will you not forget that event,

but you will remember everything that led up to that event,

which has an adaptive function

because your brain and body’s primary concern is safety.

This is the neurobiological explanation

for Maslow’s hierarchy of needs is safety first.

And so you have heightened awareness and alertness

for everything that preceded

that spike in adrenaline and cortisol.

So the way to think about this is

if you need to learn something better,

if you’re taking Adderall

or you’re taking a lot of coffee beforehand,

you’re actually driving the process in the wrong direction.

You’re increasing epinephrine for learning, sure,

but past a certain point,

you’re actually degrading learning and performance.

The time to do that is toward the end

or immediately after the learning

because this mechanism is not simply devoted

to negative events like a car crash or a trauma,

it works to make sure that the hippocampus

that encodes memories

as part of the memory encoding mechanisms

is primed that it’s told

what you just experienced is important,

you’re going to need that information later.

And so I’ve talked many times before

about using non-sleep deep rest, NSDR,

or ensuring good night’s sleep after learning,

but what we’re also talking about

is as the learning event tapers off,

as you’re exiting that,

to make sure that your epinephrine levels

are not tapering off as well.

And this may be one of the reasons

why the 90-minute cycle,

the so-called ultradian cycle for learning,

works because it takes a few minutes

to get into rhythm of learning.

You can maintain that alertness for about 90 minutes.

It’s no coincidence that these podcasts

are typically about 90 minutes long.

And as you exit that 90 minutes,

you’re going to start to feel fatigued.

You’re not going to be able to continue

to secrete epinephrine at the same level.

So I’m not telling you that at the end of this podcast,

you should give yourself a foot shock

or that you should jump into an ice bath.

Although I will say if you were to increase

your epinephrine at the end of this episode

by breathing or by way of cold shower,

I’m willing to bet based on numerous published studies

that the memory for the information would be enhanced

because of this retroactive effect

of epinephrine and cortisol.

Put simply, you can remember things better

if you increase your alertness,

aka your level of epinephrine and cortisol after,

immediately after something that you want to learn.

So I’m reminded by people here at the Huberman Lab Podcast

that the optimal strategy therefore would be

a 90 minute session of focus or learning,

then immediately after cold shower or Tumo type breathing

or ice bath or something of that sort,

maybe a hard run or hit training

if you can’t get access to the other things,

and then shower up and do a non-sleep deep rest

and then get a good night’s sleep.

Those would be the optimal tools

and the organization of tools for enhanced learning.

And of course you could use caffeine

to prime the whole process by drinking the caffeine

towards the tail of the learning episode,

which is counterintuitive, at least to me.

I should mention, since many of you use caffeine

and I use caffeine, I do drink coffee.

I love mushroom coffee.

I love mate.

I drink caffeine in various forms.

That there was a study that came out recently

that is relevant to our discussion about energy

and alertness and learning.

And the study came out just recently in March, 2021.

It’s Maghalas et al.

So M-A-G-A-L-H-A-E-S.

And it was published in Molecular Psychiatry,

which is a fine journal, a peer review journal.

And the title pretty much gives it away.

Habitual coffee drinkers display a distinct pattern

of brain functional connectivity.

Chronically drinking coffee changes brain connectivity.

And it does it in a number of ways,

but the key takeaways from this study

as it relates to sort of what the circuits do,

as opposed to me just listing off a bunch of brain circuits,

which is kind of meaningless in this conversation,

is that people who drank coffee habitually every day

had changes in their brain circuitry

such that there was a shift or a bias toward anxiety,

even when they don’t ingest caffeine.

So a lot of times we think,

oh, caffeine increases your levels of anxiety.

And indeed it appears it does if you use it chronically,

but not just to caffeine.

It doesn’t just raise your baseline of anxiety

because of what’s circulating in your bloodstream.

It actually increases connectivity

between the brain areas that relate to anxiety.

Now that could be a good thing or a bad thing,

depending on how you look at it.

For people that are prone to chronic panic attacks

or anxiety attacks, that’s not going to be good.

Some people might use caffeine in healthy ways.

I believe I do in order to just increase

overall levels of alertness.

Although now, not only am I going to start

delaying my caffeine intake till two hours after I wake up

for reasons I’ve talked about in previous episodes,

but I’m also going to start drinking it later

in learning and focus sessions as a way to enhance

plasticity around those learning and focus sessions,

not before.

So interesting study, feel free to, it’s free online.

You can access the full paper online.

We will put a link as well.

I want to mention this issue of nootropic,

so-called smart drugs,

which is not a topic that I particularly enjoy

because I don’t like the name.

I don’t like the idea of a nootropic

because what is a smart drug?

Well, there’s different kinds of smart.

There’s creativity, there’s task switching,

there’s strategy building, there’s strategy implementation.

And most of the nootropics that are out there

are just cocktails of a bunch of different things

that aren’t tailored to the individual at all.

They all seem to have some caffeine

or some cholinergic stimulation, et cetera.

But there’s an important way to frame this

in light of today’s conversation.

Nootropics generally fall into two categories.

One category are nootropics that increase blood glucose.

So these are compounds that people take

that increase blood glucose

and increasing blood glucose will improve performance

and can enhance learning in some situations.

I’m not suggesting people take these things,

but here’s just a list of a few of those.

Some of them are legal, some of them are gray market,

some of them are illegal.

Paracetams, oxiracetams, the aniracetams, all the tams,

okay, elevate blood glucose, that’s how they work.

The neural effects that you hear are secondary or tertiary

to the fact that they just increase blood glucose.

We know that because if you block the blood glucose effect,

you block the nootropic effect, okay?

Others include, and definitely don’t take these, please,

amphetamine, cocaine, those will increase learning

in the short term in particular dosages,

but because they increase blood glucose.

And then of course, things like painful stimuli or stress

will improve learning by way of increasing blood glucose.

Now, stress and epinephrine that’s associated with it,

not only improve performance during the learning bout,

but as I mentioned before,

having epinephrine come up afterward

will increase the retention of that information

in the long-term.

And then of course, there’s a whole category

of nootropics that don’t impact blood glucose

that work by increasing the cholinergic system activity.

And these are things like choline, lecithin,

fosostigmine, it’s a prescription drug,


So there are ways to increase energy

that don’t require increasing blood glucose.

And this is vitally important.

The reason we’re talking about epinephrine and cortisol

for increasing energy and immune system function

is because they are largely independent of blood glucose.

Of course, they interact with that system,

but we heard so much growing up, you need to eat for energy,

but the energy that we’re talking about today

is actually a much more powerful one

than the one that you derive from food.

It’s, we could call it neural energy.

It’s neurotransmitters that create alertness and focus

and the willingness and the ability to move

and the willingness and ability for immune system

to move in response to intruders.

So I think we all too often think about food as energy,

which is great because it is,

but there are other sources of energy that are neural

and they relate to these hormone systems,

cortisol and epinephrine,

and that’s what we’re focused on today.

So up until now,

we’ve been talking about increasing energy

and increasing the immune system

by way of cortisol and epinephrine,

but I’d be totally remiss if I didn’t cover

how cortisol and epinephrine,

if chronically elevated or if elevated too high,

can have a lot of detrimental effects.

These are the things we normally hear about.

I’m going to describe some of those things,

but I’m also going to talk about ways to ameliorate them,

ways that you can adjust the cortisol levels,

even if you’re stressed,

ways that you can adjust epinephrine levels,

even if you’re stressed,

so that they have less of a negative impact.

I don’t have to list off all the ways that stress

is terrible and chronic stress is terrible.

I think you know.

Insomnia, your immune system over time will get battered

and you won’t be able to fight infection off as well.

You don’t want to be stressed for too long.

You can start laying down the sort of classic pattern

of cortisol-induced body fat.

In fact, there’s a whole literature

related to comfort foods

and why we want to consume comfort foods

under conditions of chronic stress.

And it’s quite interesting actually,

because it reveals something

about the biology of chronic stress

that’s informative for how to prevent it

or to down-regulate chronic stress once it’s occurred.

So let’s talk for a second about comfort foods.

And the work that I’m going to refer to

is work that was done by a very impressive scientist

by the name of Mary Dahlman.

Her work goes back decades.

She was at University of California, San Francisco.

And she asked this question

that on the face of it seems kind of obvious,

but for which there was no mechanism known

until Mary and her lab personnel came along.

And the question was, why do we seek high-fat

and or high-sugar foods when we are stressed for a while?

Why would that be?

And the reason is that the so-called glucocorticoids,

of which cortisol is a glucocorticoid,

is caused, as we’ve mentioned before,

by releasing hormones from the brain,

NACTH from the pituitary, et cetera.

But normally high levels of glucocorticoids

shut off the releasing hormones in the brain

and in the pituitary.

They shut down in a so-called negative feedback loop.

So just like if testosterone or estrogen get too high,

that’s read out or that is seen, so to speak,

by neurons in the pituitary and brain,

and then we shut down our production

of estrogen and testosterone.

If cortisol levels get too high,

if there’s too much cortisol

floating around in our bloodstream,

there’s a negative feedback loop

and the brain and pituitary shut down CRH and ACTH,

which would otherwise stimulate more cortisol.

So cortisol levels go down.

So it’s a beautiful negative feedback loop.

Chronic stress, however,

stress that lasts more than four to seven days,

and there’s a way to think about what chronic stress

really is in an actionable way,

causes changes in the feedback loop

between the adrenals and the brain and the pituitary

such that now the brain and the pituitary

respond to high levels of glucocorticoids, cortisol,

by releasing more of them,

it becomes a positive feedback loop.

And that’s bad.

It actually gets right down to levels of gene regulation

and transcription and translation.

And so you really don’t want chronic stress

because it’s a cascade of stress equals more stress

equals more stress.

So this is why it’s very important

to learn to turn off the stress response.

You don’t want it elevated for too long.

So there’s one study that Dahlman and her colleagues did

where they stimulate chronic stress

by increasing corticosterone cortisol.

And they found that subjects

would increase their consumption of sugar and fat.

In fact, they would even eat lard.

It would just, it sounds disgusting,

but they were willing to just eat more fat and more sugar.

And that led to all sorts of things like type two diabetes,

led to dysfunction in the adrenal output, et cetera.

And so the real key is to learn

to shut off the stress response.

Because the interesting thing is,

is that Dahlman and colleagues

and some studies that followed up on their work

found that if the system was kicked into motion

for too long,

then there was a tremendous shift overall towards anxiety

because it turns out that body fat itself

receives neural innervation.

It received, neurons actually talk to body fat.

So now you have body fat releasing certain hormones.

You’ve got the adrenals releasing cortisol.

And all of that is feeding back to the brain

to make you want more sugar and fatty foods.

So that’s how the so-called comfort foods work.

And you should watch yourself

next time you experience stress.

If it’s a short-term bout of stress,

typically it blocks hunger.

If it’s a longer bout of stress,

typically it triggers hunger

in particular for these so-called comfort foods,

sugary and fatty foods.

And it’s kind of interesting how short-term stress

can actually block hunger.

It does that by activating or interacting with a system

called the Bombicin system.

Bombicin is a peptide hormone.

It was actually, I think it was named

after some sort of reptile or amphibian, excuse me,

some sort of toad.

I think it was initially sequenced from the toad

before it was later discovered in humans.

And I think the toad’s Latin name is Bombina bombina

or something of that sort.

And so they decided to call this thing Bombicin,

but it reduces eating and stress liberates Bombicin

and makes you want to eat less.

But chronic stress causes all these positive feedback

changes, which are not positive.

They’re positive.

I’m calling them positive because they amplify

the stress response over and over,

not because they are good for you.

So short-term stress, great.

Long-term stress, really, really bad.

Other bad effects of stress that we can talk about.

And I won’t list off too many more of these

because you know so many of them, you hear about them.

You really want to know how to control them, I’m guessing,

is that yes, indeed, stress can make you go gray.

The rates at which people go gray, meaning gray hair,

some cases gray body hair as well,

depend on some genetic factors.

There’s actually, there are a couple of ways

that we can go gray.

There’s actually a stem cell,

what they call niche in every follicle.

So you have stem cells in the follicle

that can produce more and more of the given hair cell.

And they’re actually peroxide groups.

You know, we hear about bleaching hair with peroxide,

at least in the 80s, that was a thing.

But you can use hydrogen peroxide to bleach things

and you can produce your own peroxide in the hair follicle

that will cause the hairs to go gray.

In addition, pigmentation of hair,

just like pigmentation of skin, is controlled by melanocytes.

Our old friends, the melanocytes.

And I say old friends because on previous episodes,

I talked about why sunlight and getting ample sunlight

can increase levels of certain things

like melanocytes stimulating hormone, which reduce hunger.

It can improve testosterone and estrogen levels

and all the reasons for that.

Well, it turns out that activation

of the so-called sympathetic nervous system,

which is really just another name for the system

that liberates adrenaline from the adrenals

and epinephrine in the brain,

drives depletion of melanocytes in hair stem cells.

So indeed there’s a rate of aging

that we will undergo based on our genetics,

but stress will make us go gray.

And the paper that you should look to

if you want to read more about this came out very recently.

This is Zhang et al, Z-H-A-N-G et al,

Nature, fabulous journal,

definitely one of the apex journals, 2020.

So this paper showed that the activation of stress

in various forms will deplete these melanocyte stem cells.

You do not have to worry about an ice bath

or hard exercise or breathing,

increasing your levels of stress

to the point where it’s going to make you go gray.

We’re talking again about chronic stress.

And if you want to offset the stress effects

on graying of hair,

you can do that by either having a practice

that helps you regulate stress on a consistent basis.

So something like non-sleep deep rest or meditation.

If you can get access to massages or vacations,

those are great, but having a practice

to keep stress clamped so that it’s not chronically elevated,

that will be great as well.

This is another case where sunlight,

we know stimulates melanocytes,

not just in skin, but in hair.

And so getting ample sunlight,

having a practice to regulate stress

will offset the stress-induced graying of hairs

by way of stress-induced depletion of melanocytes.

And if melanocyte sounds a lot like melanin, you’re right.

That’s because anything involved with pigmentation

in the brain and body generally has melano

in the front of the word in some way or another.

So if chronic stress is so bad

because of its effects on epinephrine and cortisol

being elevated for too long,

then the question becomes, of course,

well, what’s chronic stress?

How do I know the difference

between chronic and acute stress

and how do I keep chronic stress at bay

because of all these negative effects?

And I didn’t even list out the number of other ones,

the effects on depression,

which certainly has a correlate with elevated cortisol.

Thyroid hormone associated with,

low thyroid hormone is associated with depression,

mistimed thyroid.

Once again, getting your light and your feeding

and your exercise and your sleep

on a consistent schedule or consistent-ish

is going to be the most powerful thing you can do

in order to buffer yourself against negative effects

on mental health and physical health for that matter.

There are things that one can take,

supplements, prescription drugs, et cetera.

Some of you out there may have

or may know people that have Cushing’s,

which is chronically elevated cortisol.

There are prescription drugs that we will talk about

that can be used.

But most people are dealing with a situation

where life gets stressful, then less stressful,

stressful, then less stressful.

I would say based on the data from McEwen and others,

Bob Sapolsky’s lab over many years,

I would say any stress that lasts more than a day

or two days or three days

is starting to become chronic stress.

There’s really no strict cutoff

because we’re not measuring everybody’s cortisol

from moment to moment.

My lab has done experiments

where we measure stress in people over time.

People vary tremendously in their ability

to have a really hard day and then fall deeply asleep.

That’s going to be the ultimate reset

is the ability to sleep well,

more or less undisturbed each night,

although one or two wake-ups during the night

probably not going to be too detrimental

provided they’re not too long

and you’re not viewing light

during those wake-ups or your phone.

But the things that you can take

if you feel like you’re chronically stressed

and you’re veering toward

some of the negative effects of stress are many.

There are some simple things that people can do

in terms of supplementation.

All supplements, of course,

have to be checked out for their safety margins for you

because they’re going to differ from person to person.

You’re responsible for making sure they’re safe for you

if you decide to use them.

One of the most common ones is ashwagandha

and it has a powerful anxiolytic, anti-anxiety effect.

You’re welcome to go to

and for zero cost,

you can see their so-called human effect matrix.

Ashwagandha has many uses.

It’s been used to enhance power output in athletes.

It has been shown to modestly increase testosterone.

It has been shown to modestly adjust things

like low-density lipoprotein cholesterol,

the so-called bad cholesterol, in quotes.

It has a profound effect on anxiety.

That’s been shown in nine studies,

nine peer-reviewed independent studies,

I mean, funded by organizations

that have no vested interest in the answer.

It has a very strong effect on cortisol itself.

How strong?

The decrease in cortisol noted in humans

is 14.5 to 27.9% reduction in otherwise healthy

but stressed humans.

That’s great.

Six studies, and it mentions this is significantly larger

than many other supplements.

Now, some people will say that taking ashwagandha

chronically may not be good.

If you’ve heard about that,

or you can point to specific studies

that indicate exactly why it’s not good,

please put it in the comment section or let me know.

In the comment section on YouTube would be best.

The studies that I’m referring to did explore both genders.

The number of subjects was reasonably high, 64 or more.

One to six months studies,

so these were long-term studies, that’s great.

You’d like to see that, not just an acute study.

So males and females, lots of different ages,

overweight and non-overweight.

They did blood draws of cortisol,

which is going to end as well as saliva tests.

Saliva is actually the best way to measure free cortisol.

You can also measure it from earwax, it turns out,

which sounds pretty gross and kind of is,

but nonetheless, that’s where cortisol will accumulate

in earwax and in saliva, the free cortisol.

But that’s six very quality studies,

independently supported that all points

to these very significant, you know,

14.5 to 27.9% reductions in otherwise healthy adults.

So if you’re somebody who is dealing with chronic stress,

it’s a stressful period in your life,

and you want to stave off the negative effects of stress,

well then, ashwagandha may,

I want to highlight may, be right for you.

It also does tend to lower total cortisol,

which is interesting,

can lower depression to a somewhat minimal degree.

And can lower, as I mentioned before,

things like low-density lipoprotein.

So that, I think ashwagandha comes through

as kind of the heavy hitter in this department.

Now, what’s interesting also is the other effects

of ashwagandha that are downstream

of reducing chronic stress and cortisol,

because cortisol has so many effects.

There are receptors for cortisol

all over the body and brain.

And so I’ll just list these off quickly.

I’m not going to list off each study

or talk about how many subjects in detail.

Again, you can go to if you want

and just put in ashwagandha.

C-reactive protein, which is a marker

of all sorts of negative health effects,

cardiovascular health, even macular degeneration,

is notably reduced.

Heart palpitations, notably reduced.

Serum T3 and T4, our old friends,

the thyroid hormones from a previous episode, are increased.

Symptoms of OCD, decreased.

Both the obsessions and the compulsions, right?

Obsessions are of the mind, compulsions are of behavior.

So there are a lot of things that are downstream

of reducing cortisol.

Lowered heart rate, lowered rates of insomnia,

slightly improved memory.

Why that would be, I don’t know,

because cortisol in the short term can increase memory.

I’m guessing it’s from increased sleep.

Decreased pain, increased quality,

decreased reaction times, things of that sort.

So the list goes on and on,

but all of those things stem downstream

of decreased cortisol.

So if one were to decide to take ashwagandha

in order to reduce cortisol,

given that you want cortisol early in the day

to have energy throughout the day,

the time to take it is probably later in the day

or in the evening.

I’ve never heard of it preventing sleep

or causing insomnia of any kind.

That certainly wasn’t listed as one of the major effects


I will take ashwagandha from time to time

if I’m chronically stressed

or if I’m not sleeping as well as I ought to.

You might think that with all my knowledge

about sleep and sleep protocols

that I would sleep perfectly every night,

but unfortunately I have a dog

that has a canine form of sundowners of dementia.

So he’s up much of the night these days.

And so there’s no way I’m getting a solid night

of sleep lately.

And so I will supplement with ashwagandha

and typically I’ll take it before sleep

and maybe also with my last meal of the day,

which is at least two hours before I go to sleep.

Again, you have to decide if it’s right for you.

The dosages can vary tremendously.

I would just go by what’s on the bottle

from a reputable brand.

I would also check out

because it mentions a range of dosages

that people have used

and in various studies to different effects.

Now there is something out there

that some of you may actually be taking or ingesting

that can increase cortisol

and not so incidentally can decrease estrogen

and testosterone because remember cortisol

is made from the cholesterol molecule.

So is estrogen and testosterone.

So are estrogen and testosterone, excuse me.

And it’s competitive.

So you’re either making more cortisol

or you’re making more of the sex steroid hormones,

estrogen and testosterone.

Believe it or not, licorice,

which I always thought of as a candy,

but licorice contains a substance that I can’t pronounce.

G-L-Y-C-Y-R-R-H-I-Z-I-N glycyrrhizin,

which is of the glabra species of plant.

Actually, because of its chemistry,

this 18 beta hydroxycyrrhidic acid,

you don’t need to know all that,

licorice, black licorice,

contains a substance that increases cortisol.

And its increase is not huge, but it is significant.

This has been looked at in females age 18 to 29,

males and females age 18 to 29,

people age 30, these are separate studies

where I’m listing off the different ages,

ages 30 to 64.

Turns out that you can see pretty substantial increases

in serum cortisol and decreases in testosterone and estrogen.

So that was complete news to me.

Also increases in blood pressure

that are pretty substantial,

that’s going to be downstream of cortisol.

Increasing cortisol has increased blood pressure

in order to engage the stress response.

It’s part of the stress response.

Increased hormones of other kinds

that are associated with stress.

So who knew?

I didn’t know, maybe you knew previously,

if you did, forgive me,

but licorice and some of the compounds in black licorice

can actually increase stress,

probably not the thing to be ingesting

during periods of chronic stress.

Whether or not anyone has had positive effects

of using it to increase cortisol in other contexts,

let me know.

But very interesting that the chemistry of licorice

increases stress hormones.

And therefore you would probably want to,

almost certainly we want to avoid it

in conditions of chronic stress.

Also, if you’re trying to optimize testosterone

and estrogen, licorice seems like a bad idea.

I suppose one instance where you might want to use licorice

would be if you’re traveling

and you’re trying to wake up at a particular location

because licorice has these effects on cortisol

and cortisol is associated with the waking phenomenon

and alertness and energy, you could use it in that regard.

However, I would be careful to time it

so that you’re not getting two cortisol increases

throughout the day, two peaks.

So you’re going to want to make sure

that you’re doing all the other things correct for jet lag

and adjusting to jet lag.

And if you want to know what those things are,

including timing your feeding, using temperature,

using exercise, using light to adjust to jet lag more quickly

please see the episode that we did on jet lag and shift work

where I cover all those protocols in detail.

The other compound that I think deserves attention

is apigenin, A-P-I-G-E-N-I-N, apigenin,

which is what’s found in chamomile.

Apigenin, I’ve talked about previously,

it has various effects.

One is it is a mild anti-estrogen

that’s been shown in various studies.

And it does have a bit of an anxiolytic effect

of reducing anxiety.

I take it before bedtime, 50 milligrams.

Again, you have to decide

or figure out if that’s safe for you or not.

I’m not suggesting you take it.

The major source of action is to calm the nervous system.

And it does that primarily by adjusting things

like GABA and chloride channels,

but also has a mild effect in reducing cortisol.

So ashwagandha and apigenin together

I would consider the most potent commercial compounds

that are in supplement non-prescription form

that one could use if they were interested

in reducing chronic stress, especially late in the day

by way of reducing cortisol late in the day.

So you’re probably getting the impression

that cortisol and epinephrine

are a bit of a double-edged sword.

You want them elevated, but not for too long or too much.

You don’t want them up for days and days and days,

but you do want to have a practice

in order to increase them in the short term.

So we should talk about protocols

that can set a foundation of cortisol and epinephrine

that is headed towards optimal.

Optimization is always going to be a series

of regular practices that you do every day.

So sleeping at certain times, light at specific times,

food at specific times, certain foods, et cetera.

And that’s highly individual, but there are some universals.

And we’ve covered a number of those in the discussion today.

Meal timing, meal schedules has a profound effect

on energy levels.

And as I mentioned before,

the energy I’m referring to is not glucose energy.

It’s not burning carbs while running or ketones.

What I’m talking about is neural energy,

epinephrine and cortisol.

Fasting and timing one’s eating

are two sides of the same coin.

So even if you’re on a kind of standard three meal a day

with a couple of snacks in between diet

or a nutrition regimen, you are fasting

whenever you’re asleep or you’re not ingesting any calories.

So unless you’re hooked up to an IV of glucose,

you are fasting while you’re sleeping.

There are several different kinds of fasting

that can relate to epinephrine and cortisol.

I will do an entire episode on optimizing food intake

for performance in the sports context.

That’s coming up.

But in the meantime, I’d like to just talk about fasting

as a source of epinephrine.

Anytime when our blood glucose is low,

cortisol and epinephrine are going to go up.

If we fast for too long, that is stress.

There’s no way around that.

Now that doesn’t mean

it doesn’t have other beneficial effects.

Running a marathon is stress,

but it can also have positive effects if that’s your thing.

So stress has been demonized as a term,

but we want to think about stress mechanistically

as epinephrine and cortisol.

And then if we do that,

we can think about how to regulate its timing.

So anytime we haven’t eaten for four to six hours,

levels of epinephrine and cortisol

are going to go up pretty substantially.

There’s an exception to that,

which is if you are used to eating on the clock

every two hours or every hour,

being half hour late or being even 10 minutes late

on that schedule will induce stress.

Most of that’s psychological stress,

but also the release of things like ghrelin

that are going to make you hungry

because they’re on that eating clock.

So one thing that many people do to great benefit

is they follow a so-called circadian eating schedule.

They eat only when the sun is up,

they stop when the sun is down, more or less.

The other way to think about this

is they stop eating a couple hours before sleep

and they eat more or less upon waking,

assuming that they’re waking up more or less

around the time that the sun rises,

maybe plus or minus two hours.

Okay, so sort of typical schedule.

Now, let’s say you decide to do what I do,

which is I skip breakfast.

I drink water,

I delay my caffeine for 90 minutes to two hours,

and then I drink my caffeine.

And then my first meal is typically around lunchtime,

1130 or 12.

And yes, occasionally I throw back some almonds

or walnuts or something earlier in the day.

I do do that from time to time if I get hungry enough

or if I just happen to see them.

I’m kind of a drive-by eater.

If I see blueberries or nuts or something,

I just kind of pick them up and put them in my mouth.

I try not to do that off other people’s plates,

but I just have that habit of doing that from time to time.

But typically I don’t eat until about noon.

So I’ve got a cortisol increase,

I’ve got my sunlight in the morning,

so I’m getting a big pulse in energy early in the day.

And yes, there’s a little bit of agitation.

I am hungry sometimes early in the day, sometimes no,

but my ghrelin system is used to kicking in

right around noon.

At the point where I eat,

as long as I don’t eat carbohydrate,

in my case, I know that my epinephrine levels

are going to stay pretty high.

So for me, it’s usually meat and salad

or something of that sort or fish and salad.

I don’t particularly like eating fish because of the taste,

but I’m essentially low carb or keto-ish throughout the day.

So I’m probably in a slightly elevated state

of epinephrine and cortisol throughout the day.

Some of you are fasting even longer,

you’re pushing out till 4 p.m. or 8 p.m.,

or maybe you’re even fasting around the clock.

Anytime you’re fasting,

you’re increasing epinephrine and cortisol release.

You can do all the meditation in the world

to keep your mind calm,

but you are closer to that edge of stress

and you’re closer to that edge of peak stress.

So that’s something that’s just important to understand.

The description about comfort foods and cortisol

was one of kind of an extreme case

where cortisol systems kick over to a positive feedback loop

but we all eat to suppress cortisol and epinephrine.

When we’re hungry,

cortisol and epinephrine create an agitation

so we go seek food.

When we ingest food,

typically if it includes carbohydrate,

there’s a blunting of cortisol,

there’s a blunting of epinephrine in the bloodstream.

If you’ve ever had too much coffee to drink

and you go and have a couple of pieces of bread,

you will feel the,

we might describe it as the caffeine

getting soaked up out of your system,

but what you’re doing is you’re elevating blood glucose,

which is more or less saturating

the effect of caffeine in your system.

Not completely, but it’s going to have that effect.

If you’re very stressed and you sit down to eat something,

it will calm you down.

Yes, because some of the blood that goes to your stomach,

but more so because of these effects

in blunting cortisol and epinephrine.

So the important point here is that

if you want to be alert,

you can do that by way of not eating.

Of course, please ingest fluids.

I know some people water fast out there.

I am yet to see good science on water fasting

and why that can stimulate stem cells.

Or people love the idea

after the Nobel prize was given for autophagy

and this idea that our cells clean up debris

and senescent cells.

Yes, that’s true.

But the idea that water fasting is going to promote that,

I find rather amusing.

Please send me the data

if you know of some great study in a decent journal,

but pretty much this is something I hear about.

I don’t think water fasting is a good idea,

nor should you be drinking so much water

that you kill yourself.

You can actually drink enough water that you die.

So I think ingesting water in healthy amounts

is a good thing, stay hydrated.

But if you want to be alert, stay hydrated.

Caffeine may or may not be in your regimen,

but fasting will make sure

that your levels of energy are up

and you will be primed very well for doing a protocol

of the sort that we talked about earlier in this episode

of breathing or cold exposure or exercise

to get that increase in the immune system function.

And if you do that after learning,

after trying to learn something,

it will increase learning

for that particular set of information,

whether or not it’s motor or language

or whatever it happens to be, mathematics, programming.

So fasting is a tool for many reasons.

It can increase growth hormone, et cetera.

But today I’m talking about fasting as a tool

to bias your system toward more epinephrine

and adrenaline release and toward more cortisol release,

but still low enough that it’s not chronic stress,

that it’s not causing negative health effects.

But please know that if life is very, very stressful,

if you’re experiencing lots of stressors

and you’re chronically fasting,

you are positioning yourself toward a greater likelihood

of being chronically stressed in the ways that are negative,

negative effects on the reproductive axis,

lower testosterone and estrogen,

negative effects on your hair will turn gray.

There’s reasons for that.

Your sleep will suffer, your immune system will suffer.

So I think while it’s nuanced,

our discussion today about epinephrine and cortisol,

increasing energy and immunity are designed

to help you understand

when you should be doing certain things,

when you should throttle back,

when you might want to kick up your adrenaline a bit.

If you’re suffering from low energy

because you’re just kind of feeling down

and a little bit under activated,

well then the practices of ice baths

and intense breathing, et cetera, could be very beneficial.

So might fasting.

But if you’re feeling exhausted and burnt out,

so drained and stressed,

well then fasting or doing a lot of cold exposure

or doing a lot of intense exercise

is driving you further and further into chronic stress.

So because I don’t have a saliva test or a blood test

or God forbid an earwax test to measure your cortisol

as we’re engaging in this discussion together,

you have to gauge for yourself

whether or not you are in a state of under activated

and need more epinephrine and cortisol,

or whether or not you are over activated

in terms of cortisol and epinephrine

and you need ways to buffer those, ashwagandha.

Maybe it should be a warm mellow bath, not an ice bath.

So one has to learn how to regulate these hormones

with behavior, with nutrition, perhaps with supplementation.

And then of course there are prescription drugs.

And I always leave these to the end

because A, I’m not a medical doctor,

I’m not prescribing anything, I’m a professor,

I’m professing a number of things that you can decide

for yourselves what to do with or not.

But of course there are prescription drugs

that can increase cortisol or decrease cortisol

in cases like Cushing syndrome,

which if you have that diagnosed,

you should talk to a physician.

You should talk ideally to a endocrinologist,

but to a physician of some sort, board certified physician.

There are drugs that can be used to treat injury

like corticosterones that you can inject

to reduce inflammation and injury, but they are cortisol.

So they’re going to bias you

towards more stress in other domains.

Remember, cortisol can cross the blood-brain barrier,

so you’re going to be more prone to psychological stress.

I also want to mention again

that I think there’s great benefit to having a practice

that perhaps you do every other day, but if you can’t,

maybe every third day or every other day

of deliberately increasing your adrenaline in your body

while learning to stay calm in the mind

so that you learn to separate the brain-body experience.

You know, we hear so much about how beneficial it is

to unify the brain and body,

that we’re all out of touch with our brain and bodies.

I particularly dislike claims like that

or statements like that because there’s great power,

as we learned today, in having your body activated

by some sort of stimulus, cold water,

or even psychological stress,

but learning to stay calm in your mind.

I should just remind you that most of the negative effects

on your life and on the lives of others are due to people,

perhaps you, I hope not,

being unable to regulate their mind

when they have high levels of adrenaline in their body,

either because they read something in a text

or a comment section.

Of course, that never happens to me,

but it may happen to you.

Of course, it happens to me,

but the idea is to stay calm in your mind

so that then you can regulate your action, right?

And so I think that there are these practices

that one can develop over time

that are really straightforward and zero cost, right?

You could find any number of ways

to increase your adrenaline and stay calm,

and we tend to focus on things like exercise

as the way that we get our energy up,

but today, again, I’m talking

about deliberately increasing adrenaline

while staying calm mentally

because that has great utility

when the adrenaline hits through unwanted events,

through things that we didn’t seek out.

So the ability to regulate adrenaline and cortisol

is about inducing them deliberately

when you want to push back on infection,

potential infection from bacteria or viruses.

It’s about pulling back on adrenaline and cortisol,

maybe through the use of supplementation,

but certainly through proper use of light and sleep

and mental tools that we talked about as well

when they are chronically elevated.

It’s about training your system

not just to be unified at brain and body,

which sounds great until you’re stressed,

and then that’s terrible.

It’s really about having a deliberate dissociation

between the adrenaline response from the adrenals

and the adrenaline response from the brainstem.

So once again, we’ve covered a ton of material.

I hope right now you’re thinking,

okay, am I in a state of chronic stress?

Am I under activated?

Or could I afford to increase my levels

of adrenaline and cortisol to improve my relationship

to my immune system and to energy, neural energy?

If you like the information

that you heard today and you want to remember it,

well then, at the end of this episode,

perhaps you go do something

to increase your level of adrenaline.

And now you know what some of those things are

because it will help you retain the information.

Or you could apply that to anything else

that you learn or experience, of course.

And I hope that you’ll think about some of the ways

in which cortisol and adrenaline are not good or bad,

that stress isn’t good or bad,

but short-term stress is healthy.

Alertness and energy is healthy,

even if it puts you at the edge of agitation.

That’s an opportunity to learn

how to control these hormones better.

And I hope that if you’re in a state of chronic stress,

that you’ll do things to start tamping down

some of that stress and that you realize

that your nervous system and your hormone system are linked,

but they’re linked in ways that you can control,

that we don’t have to be slaves to our hormones

and certainly not the hormones that cause us stress.

We can learn to control those,

both to the benefit of our body and benefit of mind.

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Thank you for joining me

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about how to increase energy and the immune system

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