Huberman Lab - Sleep Toolkit: Tools for Optimizing Sleep & Sleep-Wake Timing

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.

Today, we’re talking all about sleep

and how to optimize your sleep.

This is a topic we’ve covered previously on this podcast

in the episode called Master Your Sleep.

However, since the airing of that episode,

there’s been some terrific new science to come out.

I’ve also received thousands,

yes, literally thousands of questions

related to the specific protocols covered in that episode,

as well as in the episode on jet lag and shift work.

And while today’s episode is not specifically

about jet lag and shift work,

we are going to cover tools

that will allow you to shift your schedule

if you need to for work or travel.

And we will also cover tools

that will allow you to fall back asleep

if you happen to wake up in the middle of the night,

or if you get a poor night’s sleep,

how to actually recover

from that poor night’s sleep more quickly.

And yes, indeed, even replace sleep that you’ve lost.

So today’s episode is going to be filled

with practical tools.

We will touch on some of the underlying science,

but it’s really designed to be a practical toolkit

for optimizing your sleep

depending on your specific sleep needs.

Various times throughout today’s episode,

I will refer to studies

that form the backbone of the tools that I’ll be describing.

But whereas most of the podcast episodes here

tend to be deep scientific mechanism,

and then tools, scientific mechanism, then tools,

today, I’m mainly going to focus on the practical tools

that anyone, indeed, all people, I believe,

should use in order to optimize their sleep.

Why should everybody want to optimize their sleep

and put considerable effort into optimizing their sleep?

Well, put simply,

sleep is the foundation of mental health,

physical health, and performance of all kinds,

cognitive performance, physical performance, et cetera.

It also controls things like our immune system,

wound healing, our skin health, and our appearance,

whether or not we can think clearly or not,

whether or not we will live as long as we possibly can

or not, whether or not we suffer

from dramatic age-related cognitive decline or not.

In other words, whether or not we keep our memory as we age.

I could go on and on about all the terrible things

that can happen to somebody if they don’t sleep well.

Thanks to the great work of Professor Matt Walker

at University of California, Berkeley,

and the wonderful book that he wrote,

Why We Sleep, I think the world is largely on board now

that sleep is critical to our health,

our mental health, our physical health, and our performance.

But what’s not often discussed is how great life is,

that is how much more focused and energetic

and how positive our mood gets when we are sleeping

for the appropriate amount of time at the appropriate depth

and when we were doing that regularly.

Basically everything in life gets better

when we’re sleeping well.

So today I’m going to teach you the tools

that will allow you to optimize your sleep.

That is get to sleep and stay asleep,

fall back asleep if you wake up in the middle of the night

and adjust your sleep given the various life demands

you may be experiencing.

Before we begin, I’d like to emphasize that 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 Element.

Element is an electrolyte drink with everything you need

and nothing you don’t.

That means plenty of salt, magnesium and potassium,

the so-called electrolytes and no sugar.

Now, salt, magnesium and potassium are critical

to the function of all the cells in your body,

in particular to the function of your nerve cells,

also called neurons.

In fact, in order for your neurons to function properly,

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in the proper ratios.

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I typically drink Element first thing in the morning

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I’m pleased to announce that the Huberman Lab Podcast

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Today’s episode is also brought to us by Eight Sleep.

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with cooling, heating, and sleep tracking capabilities.

It turns out that your body temperature

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Let’s talk about sleep and tools to optimize your sleep.

I want you to conceptualize yourself

as contained within a room that has only very few windows

or very few entry points.

What do I mean by this?

Well, your brain and your nervous system

control whether or not you move or don’t move.

They control whether or not you’re digesting food

or you’re not digesting food.

They control whether or not you’re stressed or not stressed,

happy or sad, et cetera.

All of that stuff that controls all that stuff

is housed inside your skin and skull, et cetera.

That might seem pretty obvious,

but what that means is that for your brain and body

to feel alert and focused, ready to move and exercise

or do some work, or if your brain and body

are going to lie down and go to sleep,

well, that brain and body needs cues.

It needs inputs to determine

when to do those different things.

And those cues and inputs arrive through a defined set

of what I’ll call stimuli,

but you can also think of these as levers or tools.

The main levers and tools that are going to allow you

to control when you are awake and when you are asleep

and to get better sleep every single night are light,

literally photons, light energy, could be from sunlight,

could be from artificial light.

We will discuss those particulars in a moment,

as well as darkness.

That is the absence of light.

So we’ve got light and dark.

Those are two very powerful tools

to encourage your nervous system

to be in one state or another, meaning awake or asleep.

Temperature is another tool or lever.

It turns out that when your body is cooling down,

you have a greater tendency to fall and stay asleep.

In fact, every night when you actually sleep,

your body is dropping by one to three degrees

and that drop in temperature is required.

It’s like a gate that your body has to go through

in order for you to get into sleep.

And in fact, the converse is also true.

If your body heats up by one to three degrees or so,

you will wake up.

So you’ve got light, dark, temperature, food.

And when we say food, we mean what we eat,

when we eat and the amount that we eat.

Okay, so light, dark, temperature, food, exercise.

And of course, exercise comes in different forms.

We can do cardiovascular exercise.

That can be low intensity, long distance exercise.

It can be high intensity,

so-called high intensity interval training.

It could be weight training, it could be yoga,

it could be swimming, any number of different activities.

But exercise in general causes an increase

in body temperature and tends to make us more alert,

not just during the exercise,

but in the immediate hours after that exercise.

Exercise does some other things

that relate to our sleep as well.

And we’ll talk about those today

and how you can leverage them.

Another potent lever for adjusting your sleepiness

and wakefulness is caffeine.

This of course comes as no surprise to people,

but why and how caffeine works

might come as a surprise very briefly.

We have a molecule in our body called adenosine.

And the longer we have been awake,

the more adenosine builds up in our brain and body.

And adenosine is part of the reason why we get sleepy.

Caffeine effectively operates as a adenosine antagonist.

It works by basically occupying the receptor for adenosine.

So it’s a little bit of a convoluted mechanism,

but basically all you need to know

is that caffeine prevents the actions of adenosine.

That’s one of the reasons why caffeine makes us feel alert.

But how much caffeine we drink and when we drink caffeine

turns out to be vitally important

for adjusting our wakefulness and for optimizing our sleep.

So we’ll talk about that as well.

The other category of lever tools,

which are immensely powerful for optimizing sleep

are supplements.

There now exist as many as eight different supplements

that can powerfully modulate sleep in healthy ways

and that have huge margins for safety.

We’re going to talk about what those supplements are.

In previous episodes of this podcast

and as a guest on other podcasts,

I’ve talked about three particular supplements,

magnesium threonate, apigenin and theanine,

which together can really enhance the speed

at which one falls asleep

and people’s ability to stay asleep

and to really get into those deep stages of sleep.

They’re particularly restorative.

Today, we’re going to talk a little bit more

about each of those three

and how they can best be used in combination.

But we are also going to touch on some other supplements

that I have not talked about much before, if at all.

Things like glycine and GABA, as well as inositol.

Many people are going to find inositol interesting

and of particular use to them,

especially if they’re following a low carbohydrate diet

or if they are fasting before sleep

or just trying to avoid eating too close to bedtime

and yet they’re having a hard time falling asleep.

Inositol also turns out to be especially useful

for people who have a tendency to wake up

in the middle of the night

and have a hard time falling back asleep.

It also has some interesting and potent effects

on anxiety throughout the day.

So we’re going to talk about inositol as a tool as well.

And then last in our list of general categories

of levers and tools for optimizing sleep are digital tools.

When I say digital tools,

I don’t necessarily mean devices.

What I mean are things like non-sleep deep rest scripts.

These are zero cost scripts that you listen to

that take your body through some deep relaxation

and that can help people both fall asleep, stay asleep,

fall back asleep, and get better at sleeping.

Also going to talk about digital tools

related to self-hypnosis.

This is distinctly different from stage hypnosis.

So I know some of you hear hypnosis and you think,

oh, you know, people, you know, clucking like chickens

and doing things that are outside their control.

That’s not at all what I’m referring to here.

I’m talking about clinically and research supported tools

that have been shown to enhance people’s ability to fall

and stay asleep and that can get you far better at sleeping.

So again, to recap the list of levers and tools,

we’ve got light and dark,

and that includes the intensity of light,

the timing of light, et cetera.

We’ve got temperature, we have food,

we have exercise, caffeine, supplements, and digital tools,

not just limited to devices,

but zero cost tools that you can access on YouTube

and elsewhere in various apps

that can really help you optimize your sleep.

So today we’re going to talk about all of these.

I really want to provide you as many tools as possible,

give you the logic behind each of those tools

and when and how best to apply them

so that you can develop the sleep toolkit

that’s ideal for your sleep needs.

As we head into our description

of tools for optimizing sleep,

let’s consider what the perfect 24-hour cycle

would look like.

Let’s start this 24-hour cycle

with when you wake up in the morning.

So for some of you, that will be 5 a.m.,

for others of you, that will be 10 a.m.

Most people, I believe,

wake up sometime between 6.30 a.m. and 8.30 a.m.

But regardless of when you wake up in the morning,

one of the first things that happens

is that your body temperature is increasing,

and that’s just going to happen naturally.

Some of it is going to be the consequence

of your moving around a bit,

but really the increase in body temperature

is one of the main triggers

for why you woke up in the first place.

That increase in body temperature, in turn,

causes an increase in the release

of a hormone called cortisol.

Cortisol is often discussed as a stress hormone,

but it’s not just associated with stress.

It also enhances your immune system,

provided cortisol is elevated at the right times,

and the right time for cortisol to be elevated

is when you first wake up in the morning.

That increase in cortisol

is also going to increase metabolism.

It’s also going to increase your ability to focus mentally

and for you to move your body.

So again, cortisol is often demonized

and considered this bad thing,

and indeed, you don’t want cortisol to be chronically

or consistently elevated throughout the day or night,

but you do want cortisol to reach its peak early in the day,

right about the time you wake up.

One way that you can ensure

that that cortisol peak occurs early in the day,

right about the time that you wake up,

is to view bright light, ideally from sunlight,

within the first 30 to 60 minutes after waking.

That’s right.

View bright sunlight

within the first 30 to 60 minutes after waking.

I’ll get into all the caveats

about what happens if you wake up before the sun is out.

What if you live in the UK where there is no sun

or people claim there is no sun?

Hate to tell you this folks, but there is sun in the UK.

We’ll talk about all that.

But everybody, whether or not you live in a cloudy place

or a sunny place, whether or not there’s cloud cover

or not that day, should really strive

to get bright light in your eyes, ideally from sunlight,

within the first 30 to 60 minutes after waking.

The reason for that is very simple.

You want to trigger that cortisol increase

to occur very early in your day.

And you don’t want that cortisol peak to happen later,

which is what will happen

if you wait to get outside and see sunlight.

The reason for this is that you have a set of neurons,

nerve cells in your eye,

they’re called intrinsically photosensitive melanopsin cells,

but you do not need to know that name.

Those neurons respond best to bright light.

And especially right after waking early in the day,

they are best able to signal to a set of neurons

that reside over the roof of your mouth,

called the suprachiasmatic nucleus,

which is a cluster of neurons

that then sends a huge number of other signals,

electrical and chemical, out to your entire body

that triggers that cortisol increase,

provides a wake-up signal for your brain and body,

and sets in motion a timer

for you to fall asleep later that night.

So again, we’re not trying to go into too much mechanism.

Today, we are trying to really hammer on tools,

and I’ll substantiate those tools

just a bit with some mechanism,

but here’s what you do, or at least here’s what I do.

I wake up in the morning and I want to reach for my phone,

but I know that even if I were to crank up the brightness

on that phone screen,

it’s not bright enough to trigger that cortisol spike

and for me to be at my most alert and focused

throughout the day and to optimize my sleep at night.

So what I do is I get out of bed and I go outside,

and if it’s a bright, clear day,

and the sun is low in the sky,

or the sun is starting to get overhead,

what we call low solar angle,

then I know I’m getting outside at the right time.

If there’s cloud cover and I can’t see the sun,

I also know I’m doing a good thing because it turns out,

especially on cloudy days,

you want to get outside and get as much light energy

or photons in your eyes.

But let’s say it’s a very clear day

and I can see where the sun is.

I do not need to stare directly into the sun.

If it’s very low in the sky,

I might do that because it’s not going to be very painful

to my eyes.

However, if the sun is a little bit brighter

and a little bit higher in the sky,

sometimes it can be painful to look at.

So the way to get this sunlight viewing early in the day

is to look toward the sun.

If it’s too bright to look at directly,

well then don’t do that.

You just look toward it, but not directly at it.

It’s absolutely fine to blink.

In fact, I encourage you to blink

whenever you feel the impulse to blink.

Never look at any light, sunlight or otherwise,

that’s so bright that it’s painful to look at

because you can damage your eyes.

But for this morning sunlight viewing,

it’s best to not wear sunglasses.

That’s right, to not wear sunglasses,

at least for this morning sunlight viewing.

It is absolutely fine to wear eyeglasses or contact lenses,

so-called corrective lenses.

In fact, those will serve you well in this practice

or this tool because they will focus the light

onto your neural retina and onto those melanopsin

intrinsically photosensitive ganglion cells.

If your eyeglasses or contact lenses have UV protection,

that’s okay.

There’s so many different wavelengths of light

coming from the sun and they are bright enough

that they will trigger the mechanisms

that you want triggered at this early time of day.

So try and get outside,

ideally within the first five minutes of waking,

or maybe it’s 15 minutes,

but certainly within the first hour after waking.

I want to share with you three critical things

about this tool of morning sunlight viewing.

First of all, this is not some woo biology thing.

This is grounded in the core of our physiology.

There are literally hundreds,

if not thousands of quality peer reviewed papers

showing that light viewing early in the day

is the most powerful stimulus for wakefulness

throughout the day.

And it has a powerful positive impact on your ability

to fall and stay asleep at night.

So this is really the foundational power tool

for ensuring a great night’s sleep

and for feeling more awake during the day.

Second of all, if you wake up before the sun is out,

you can, and probably should flip on artificial lights

in your internal home environment or apartment

or wherever you happen to live,

if your goal is to be awake, right?

If you wake up at four in the morning

and you need to be awake,

well then turn on artificial lights.

Once the sun is out, however, once the sun has risen,

then you still want to get outside and view sunlight.

Some of you will wake up before the sun comes out.

And if you’re asking whether or not turning on

artificial lights can replace sunlight at those hours,

unfortunately, the answer is no.

Unless you have a very special light.

We’ll talk about what kind of light.

The bright artificial lights in your home environment

are not, I repeat, are not going to be sufficiently bright

to turn on the cortisol mechanism

and the other wake-up mechanisms

that you need early in the day.

The diabolical twist, however,

is that those lights in your home or apartment

or even on your phone are bright enough

to disrupt your sleep if you look at them too late at night

or in the middle of the night.

So there’s this asymmetry in our retinal, our eye biology,

and in our brain’s biology,

whereby early in the day, right around waking,

you need a lot of light, a lot of photons,

a lot of light energy.

And artificial lights generally just won’t accomplish

what you need them to accomplish.

But at night, even a little bit of artificial light

can really mess up your so-called circadian,

your 24-hour clocks and all these mechanisms

that we’re talking about.

So if you wake up before the sun is out and it’s still dark,

please turn on as many bright artificial lights

as you possibly can or need,

but then get outside once the sun is out.

On cloudy days, you especially need to get outside.

I repeat, on cloudy days, overcast days,

you especially need to get outside and get sunlight.

You just need to get more of it.

Now, how much light and how much light viewing do you need?

This is going to vary depending on person and place,

literally where you live on earth,

whether or not there’s a lot of tree cover,

whether or not you’re somebody who has sensitive eyes

or less sensitive eyes.

It’s really impossible for me

to give an absolute prescriptive,

but we can give some general guidelines.

In general, on a clear day,

meaning no cloud cover or minimal cloud cover,

you want to get this sunlight exposure to your eyes

for about five minutes or so.

Could be three minutes one day, could be seven minutes

the next day, about five minutes.

On a day where there’s cloud cover,

so the sun is just peeking through the clouds

or it’s more dense cloud cover,

you want to get about 10 minutes of sunlight exposure

to your eyes early in the day.

And on days that are really densely overcast

or maybe even a rainy,

you’re going to want to get as much as 20 or 30 minutes

of sunlight exposure.

Another key thing is do not forget about,

just don’t try and get this sunlight exposure

through a windshield of a car or a window,

whether or not it’s tinted or otherwise.

It takes far too long.

It’s simply not going to trigger the relevant mechanisms.

You would be standing there all day

trying to get enough light into your eyes

from the morning sunlight.

And by then the sun will have already moved

from low solar angle to overhead.

And it simply won’t work for all sorts of mechanisms

related to your circadian rhythm functions.

So just don’t try and do it through a windshield,

sunglasses, or a window.

It’s just not going to work.

Get outside.

If the weather is really bad or for whatever reason,

safety reasons, you cannot get outside,

well then I suppose try and get near a window.

That would be the last, last resort.

But you really want to get outside

to get the sunlight exposure.

Now, if you live in a part of the world

where it’s extremely dark and overcast,

or the weather won’t let you outside,

or you live in a cave or some other small box

that does not allow any natural light into it

for whatever reason,

well then you’re going to need a replacement

for that sunlight.

And there are sunlight simulators or daylight simulators

that you can purchase.

Those are quite expensive in general.

And therefore I suggest cheaper options

that work just as well because they get just as bright.

Things like ring lights that are sold

in order for people to take selfies and this kind of thing.

A drawing LED tablet will work pretty well.

I actually have one of those

and I put it on my desk all morning,

even though I still get outside

and look at sunlight first thing in the morning.

Again, also, especially I should say on cloudy days.

We do not have any affiliation to any ring lights

or LED lights or these panels.

So we will provide a link to a couple of different options.

If you want to explore the various options,

I don’t know what people’s different budgets are.

I don’t know where people live.

I just know that many of our listeners

live in locations throughout the world where for instance,

during the winter, it gets very, very dark.

So they can’t get sufficient sunlight,

but get that morning light ideally from sunlight

and take into account all the specific points

that I’ve given you here.

And I should say, enjoy this practice.

It’s really nice to get outside first thing in the morning

and get the sunlight.

In fact, when you start doing this,

you’ll notice that your body will start

to feel more energized

and it will feel more energized more quickly.

You’ll actually start to notice this mechanism

kicking in each day,

especially if you’re paying attention to your physiology.

So enjoy this practice of getting outside.

Yes, you can take your morning beverage outside.

Yes, you can take your dog with you.

In fact, animals intuitively know

to get this morning sunlight.

They actually seek it out at the right times of days.

We human beings need to be told by podcasters

and other people about the science

that supports these kinds of practices.

Our pets apparently do not,

but get outside alone or with somebody,

with your kids, with your dog,

however you go about this practice,

make sure you do this practice

at least 80% of the days of your life.

That’s right.

If you miss a day, for instance,

you’re bedridden for a day,

try and get next to a window.

Let’s say you are traveling or for whatever reason,

you are not able to get outside

first thing in the morning.

Well then try to get twice as much sunlight in your eyes,

or I should say,

extend the duration of sunlight viewing in the morning

for twice as long the following day.

This is a slow integrative mechanism

that underlies this whole thing of wakefulness

during the day and sleep at night due to sunlight viewing.

And if you miss a day,

you can make up for it the next day,

but you have to get twice as much light

or twice as much duration of light.

If you really want to get technical

and you really want to measure

how much light is in your environment,

you can download a free app,

something like Light Meter.

And that will allow your phone

to act as a bit of a light meter.

It gives you a pretty accurate measurement

of how many lux,

which is a measure of brightness

are in your environment in the morning.

And in general,

that’s just going to be a good tool

for evaluating your environments.

Here’s what I suggest you do.

Wake up in the morning,

take Light Meter,

point it at the brightest light in your home

and take a measurement.

And what you’ll probably find is it’s about a thousand lux.

Now go outside.

And if there’s some sunlight out

and there’s cloud cover,

point it at the sky and press that button.

You can actually hold it down

and it’ll give you a dynamically updated lux measurement.

And what you’ll find is like 5,000, 10,000,

sometimes even 90,000 lux,

even though you don’t experience it as so much brighter.

And that’s because an indoor artificial light

is very concentrated over a small spatial area,

whereas the sunlight is very diffuse,

but it’s that diffuse, very bright sunlight,

that photon energy that you really want

that’s going to set all the rhythms of your brain and body

in the proper way,

not just that cortisol peak,

but it’s going to trigger proper metabolism.

It’s going to set a timer for you to be able to fall asleep

about 16 hours later and on and on and on.

And I should mention within the on and on and on,

it’s also going to suppress any melatonin,

a hormone that makes you sleepy,

that happens to be swimming around in your bloodstream

at the time you wake up.

It does a number of other things too,

including interact with the adenosine system

and kind of wash out some of the adenosine

that might still be residual if you didn’t sleep enough.

Fundamentally speaking, get that morning sunlight viewing.

I promise you will be grateful that you did.

It makes everybody feel better, feel more alert,

and it will greatly assist with your ability to fall

and stay asleep later that night.

I’d like to take a quick break

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Okay, so now we’re still focusing

on this early part of the day when you’ve woken up,

like the first hour or so after waking.

And we can go to our list of other levers and tools, right?

We have light and dark.

We already talked about light and sunlight in particular.

We’ve got temperature, food, exercise, caffeine,

supplements, and digital tools.

Now, once you’ve woken up and you want to be awake, okay?

So this is likely to be early in the day

if you’re following a more standard schedule.

You will also want to leverage not just light,

but temperature as a tool.

If you are inclined, it would be wise to try

and increase your core body temperature a bit more quickly

than it would otherwise if you were to just, you know,

shuffle around outside, get your sunlight,

maybe read a little bit, et cetera.

And there are two main ways you can do that.

The first way is to get into cold water of some sort.

This could be a cold shower

of anywhere from one to three minutes.

This could be an ice bath.

If that’s your thing, it could be a cold tub.

Or if you own a cold tub that’s specifically designed

for deliberate cold exposure, get under some cold water.

That will certainly wake you up.

And if you’ve ever jumped into cold water

or had a cold shower, you know it really wakes you up

because you release adrenaline, epinephrine

from both your brain and body.

The body from your adrenals and your brain

from a little cluster of neurons called locus coeruleus.

Again, the names don’t matter.

One to three minutes of cold water exposure

will wake you up because of that adrenaline release.

And, and I want to highlight the and,

it will serve to increase your core body temperature.

That’s right.

Your body and brain interact as a bit of a thermostat system

where if you put something cold on the surface of your body,

your brain, a little cluster of neurons

in the so-called medial preoptic area,

act as a thermostat and say, ah,

the external of my body is cold.

And therefore I’m going to heat up my core body temperature.

So there’s a little bit paradoxical.

People think, oh, if you get into cold water or an ice bath,

your body temperature is going to drop.

And indeed that’s true if you stay in for a while,

but if you just get in for about one to three minutes

or under the cold shower for one to three minutes,

your core body temperature will increase.

So then when you get out of that cold water,

your body temperature is increasing at a rate,

at a slope that’s steeper than it would otherwise.

And you’re going to feel more alert.

It also has the advantage of increasing,

not just adrenaline, but dopamine,

which is a molecule involved in motivation, focus, et cetera.

So this is great for waking up.

So we’ve got sunlight,

we’ve got temperature triggered by cold water,

and we have exercise.

One of the best ways to increase your core body temperature

early in the day is to do exercise.

Now, some of you might choose to do your full-blown workout

for the day first thing when you wake up in the morning.

I always say the best time to exercise,

at least what the research points to,

is immediately when you wake up in the morning

or three hours after waking or 11 hours after waking.

But that’s really getting down into optimization

for sake of muscular strength and grip strength.

And it’s very hard to give a strict prescriptive.

Here’s what I suggest.

If you want to be alert early in the day

and you want to sleep great at night,

get that bright sunlight, get into some cold water.

And if you don’t want to get into some cold water,

try and get some movement.

It could be a walk.

So you can get your sunlight exposure

while you’re taking a walk first thing in the morning.

It could be a light jog.

It could be skipping rope.

These days I skip rope for about 10 minutes or 20 minutes

while looking at the sun.

So I’m trying to layer in these different things

for waking up.

And then I take a cold shower afterwards.

This is what I’ve been doing as of lately,

but I don’t do that all year long necessarily.

Or some of you are going to be working out mid morning.

I sometimes do that,

but try and get your core body temperature increased

first thing in the morning.

And a great way to do that is with the cold water

and or with exercise.

And again, it doesn’t have to be your full blown workout

for the day if you’re doing workouts consistently,

which I hope everybody is

because everybody really should exercise

at least I believe five or six

or maybe even seven days a week.

For me, it’s six days a week, sometimes five,

rarely is it seven.

So get that exercise

or even just a modest amount of movement,

walking, jogging, skipping rope, some light calisthenics.

That will further increase your core body temperature

and help you feel more awake.

Then we have the category of caffeine.

And again, we’re just talking about this early part

of the day and you might be saying, wait a second,

I thought this was an episode about tools for sleep.

Well, everything that we’re talking about doing

in these first 60 to 90 minutes of the day,

really set in motion a wave of biological cascades

that carry through the entire day and into the evening

and into the night and really do serve to optimize sleep.

So just hang in there with me.

And for those of you that are interested in focus

and attention, your ability to learn all of these tools

and practices are going to greatly enhance those as well.

So the next category of tool for use early in the day

is caffeine.

Caffeine is a very important compound to think about.

I do realize that some people who are prone to anxiety,

especially panic attacks, anxiety attacks

might avoid caffeine entirely.

That’s absolutely fine.

You do not have to drink caffeine.

So what I’m about to describe are ways to leverage caffeine

use to optimize sleep and wakefulness.

If you are comfortable with caffeine, if you like caffeine,

I happen to love caffeine.

I like it in the form of coffee or espresso

or yerba mate tea.

In particular, non-smoked varieties of yerba mate teas.

Non-smoked because the smoked varieties seem to carry

some carcinogenic, some cancer causing risk.

There’s increasing data on that.

So non-smoked varieties of yerba mate.

So caffeine is something that a lot of people consume

early in the day.

How much depends on your tolerance.

And there’s a lot of individual variability here.

Again, caffeine is a adenosine antagonist

or effectively works as a adenosine antagonist

and limits sleepiness.

I highly recommend that everybody delay their caffeine

intake for 90 to 120 minutes after waking.

However painful it may be to eventually arrive at that 90

to 120 minutes after waking.

You want, and I encourage you to clear out whatever

residual adenosine is circulating in your system

in that first 90 to 120 minutes of the day,

get that sunlight exposure, get some movement to wake up.

And then, and only then start to ingest caffeine

because what you’ll do if you delay caffeine intake

until 90 to 120 minutes after waking

is you will avoid this so-called afternoon crash.

And you may still get a little bit of dip in energy

in the afternoon, but it’s not going to be

that massive crash.

I’ve talked about the reasons for that crash

on previous episodes.

But if you delay your caffeine intake 90 to 120 minutes

after waking, you are doing yourself a great service

towards wakefulness and to avoid the crash.

And the afternoon crash has another liability to it,

which is typically people will emerge from that afternoon

crash, either grumpy or groggy,

and then they’ll lean into drinking more caffeine,

which can then disrupt their sleep.

So wait 90 to 120 minutes after waking in the morning

to drink caffeine.

And if you drink caffeine at any point throughout the day,

really try and avoid any caffeine.

Certainly avoid drinking more than a hundred milligrams

of caffeine after 4 p.m.

And probably even better to limit your last caffeine intake

to 3 p.m. or even 2 p.m.

And for many people shifting that caffeine intake

from immediately after waking in the morning

to 90 to 120 minutes,

gives them a much longer arc of energy throughout the day.

And they don’t feel the need to drink more caffeine

later in the afternoon.

If you do drink caffeine later in the afternoon,

really try and limit the total amount or drink decaf.

Certainly keep the total amount to less than a hundred

milligrams if you are interested in getting into the best

possible sleep.

And I say this knowing that many people, including myself,

can drink a double espresso with 200 milligrams of caffeine

or more at 5 p.m. or even 6 p.m. or after dinner,

and still quote unquote fall asleep fine

or still sleep fine.

However, there are terrific data.

Matt Walker and I talked about this,

and there are more and more papers all the time that point

to the fact that caffeine intake late in the day,

after 4 p.m. that is,

can really disrupt the architecture of your sleep.

So you might think you’re sleeping well,

but you’re not sleeping nearly as well as you could

if you avoided caffeine in those afternoon hours.

Now, some of you might be doing your main bout of exercise

first thing in the morning,

and you want your caffeine before that bout of exercise.

In that case, I say, go for it.

Drink your caffeine, do your workout right after waking up.

I don’t have a problem with that.

You will find, however,

that you’re going to get an early afternoon dip in energy.

And that dip in energy is going to be substantial because

it’s going to be a dip in energy that naturally follows that

workout from the morning.

So it’s dependent on temperature,

and it’s going to be related to the elimination of that

adenosine blockade by caffeine.

So you’re getting a kind of a one,

two punch on your energy levels by taking a lot of caffeine

and exercising early in the day,

you can sort of expect that you’re going to get a drop in

energy in the early afternoon.

That’s okay if that’s works for you,

but just know that delaying that caffeine 90 to 120 minutes

after waking would be the ideal scenario,

most days and most scenarios.

All that said,

I absolutely respect the fact that people have different work

schedules, kid schedules, et cetera.

So if you want to do some or none or all these tools,

that’s really up to you.

I’m just providing them to you in the simplest form that I

can possibly provide them.

Now, the other lever or tool that you have available to you

is food, not just what you eat, but when you eat.

And it turns out that if you eat early in the day,

you support a biological clock mechanism that will make you

more alert early in the day.

That said many people choose to fast in the early morning

hours of the day or in the first part of the day,

I’m one such person.

I generally don’t ingest any food until about 11 AM or 12

noon. Sometimes I’ll have a protein shake.

Sometimes I’ll have some almonds.

Sometimes I’ll have breakfast.

If people are meeting for brunch or breakfast,

I will have breakfast for social reasons every once in a

while, but most of the time I don’t eat until about lunch

time. However,

some people are really hungry when they wake up in the

morning, just know that if you eat early in the day,

you are further triggering an increase in metabolism and in

temperature that will make you more alert.

So you don’t have to eat early in the day,

but you can start to see how these different tools layer

together, sunlight, viewing exercise, cold water, eating.

Many of them are converging on the same mechanisms.

In fact, when you drink caffeine,

there’s also a small increase in body temperature due to the

adrenaline increase that it stimulates.

So all of these things can be layered on top of one

another, or you can use them individually or think about

them individually.

Now food is an interesting lever or tool because it’s not

just about when you eat, but it’s also about what you eat.

And I’ve talked a lot about eating for energy and what that

means in terms of caloric energy versus neural energy,

et cetera, in previous podcast episodes,

we’re not going to focus on that now because frankly,

to get into a description of whether or not somebody should

eat fruits or vegetables or animal proteins or dairy,

et cetera, early in the day, that’s very nuanced.

But what you eat for your breakfast,

or if you choose to not eat breakfast is really up to you.

All that said, if you eat a very large meal,

it doesn’t matter if you slept terrifically well,

10 hours the night before,

or if you are about to go to sleep,

or if it’s the middle of the afternoon,

if your gut is full of food,

there’s just a large volume of food in your gut.

It’s going to divert a lot of blood and other critical

resources away from other organs of your body,

in particular, your brain,

and you’re going to be sleepy after eating a big meal.

So this is sort of a duh,

but I think oftentimes in the discussions about what to eat

for energy,

people neglect to consider food volume as a strong parameter

or variable in that discussion.

So if you eat a huge breakfast,

it’s likely that you are going to be tired immediately

after eating that breakfast,

unless of course you exercise very hard prior to that.

And you metabolize all that food very quickly.

So it’s up to you whether or not to eat first thing in the

morning or not.

But if you do eat in the first few hours of the morning,

just understand that you are setting,

or you’re helping to set a food in trained as it’s called

circadian clock, light, temperature,

timing of food intake, movement, and exercise.

All of these things literally funnel in, in a neural sense,

they funnel into this thing that we call the circadian

clock, and they let that clock,

that set of neurons predict when you are likely to be eating

and active and viewing sunlight the next day.

And the next day and the next day,

I say all this because there are some beautiful studies and

I’ll highlight one again in the show note captions that show

that if people are having a hard time waking up in the


one of the things they can do is maximize sunlight viewing

exercise in the morning, drink caffeine.

Although again,

I support the idea that that would best be done about 90 to

120 minutes after waking,

eating some food in those early morning hours, et cetera,

et cetera,

you can layer in multiple levers or tools in order to be

more alert.

And that’s what these levers and tools are really there for

in this sense of what we’re talking about today,

which is optimizing sleep.

Yes, they will make you more alert.

Yes, they will provide some adrenaline and dopamine,

for instance, the cold water, et cetera, et cetera.

But the reason we’re talking about these things in the

context of sleep is that they start to give your body some

predictable autonomic timing.

What is predictable autonomic timing?


your autonomic nervous system is the components of your brain

and body that cause wakefulness and sleepiness.

And you can start to create some predictability in that

autonomic timing.

You can start to do things that really make it such that you

naturally wake up at six in the morning or five in the

morning. That’s right.

If you’re somebody who naturally is a night owl,

who likes to stay up until two in the morning and sleep until

10 AM and you now have a job or you have to go to school or

you have a partner that likes to get up early and go to

sleep early.

Well, you can make that happen.

And you can make that happen pretty painlessly.

If you take a week or so and go to sleep 30 minutes or an

hour earlier each night,

set an alarm and wake up 30 minutes or an hour earlier each

morning until of course you’re waking up at the time you

want to wake up.

And then even in that groggy state, get some exercise,

get some sunlight viewing.

If the sun’s not out, turn on those bright,

artificial lights, have some breakfast.

Even if you’re not hungry.

In fact, for those of you that engage in shift work,

because you have to or travel and you’re jet lagged,

one of the quickest ways to shift your circadian clock and

get onto the local schedule is to eat on the local schedule.

So what all these tools do is they really set up a cascade.

Think of it as kind of a wave front of wakefulness and

focus throughout the day.

It’ll take you through the middle of the day in the

afternoon stages we’ll talk about in a few minutes,

but really they take you to this period that is about 5 PM

until your bedtime.

I realize some people are going to bed very early,

like 8 PM or 9 PM, which to me seems very early,

but very few people go to sleep at 5 PM, right?

Unless you’re doing that for shift work or other reasons,

but from 5 PM until bedtime is really a critical period in

which you need to leverage particular tools in order to get

and stay asleep optimally and to be able to sleep through

the night.

So really there are three critical periods throughout each

24 hour cycle.

And during each of those critical periods,

you’re going to want to do as many specific things as you can

to optimize your wakefulness and focus and mood throughout

the day and your sleep at night.

The first critical period is the one that we’ve been talking

about up until now.

Things like morning sunlight, viewing caffeine,

90 to 120 minutes after waking, exercise, and so on.

We can call that critical period one.

And it really encompasses the time from which you wake up

until about three hours after waking.

Although I should just mention,

because there are always those people say, wait,

I wake up at 4 AM and the sun isn’t out until 8 AM.

Okay, so it might be four hours,

but really it’s those early morning hours of your day.

Once you’re awake.

The second critical period is the time throughout the day and

afternoon leading into evening.

So you may ask what are the things that you can do

throughout the day,

the middle of your day and into the afternoon and evening

hours that are really going to set you up for the best

possible sleep later that night.

Well, there are a few do’s and there are a few don’ts.

First of all,

be careful about ingesting too much caffeine throughout the

middle of the day.

That’s kind of an obvious one for the reasons that we talked

about earlier.

Second of all, if you are a napper and I raise my hand now,

for those of you listening,

I’m raising my right hand because I love naps.

I’ve always loved naps.

Nowadays I do NSDR or a reverie sleep hypnosis almost every


And I tend to do that, as I mentioned,

in the early afternoon hours, if I’m feeling kind of sleepy,

because even though I optimize my caffeine intake,

timing, et cetera,

I tend to get a little sleepy in the afternoon.

Most people get a little sleepy in the afternoon.

Some of that is related to hitting that peak of body

temperature. And you might think, wait,

I thought high body temperature is associated with alertness

and it is,

but right as you crest that high body temperature and your

body temperature starts to drop,

there’s a tendency to be a little bit sleepy.

So some of you might opt to take a nap in the afternoon.

Should you nap? Should you not nap?

That’s a question that I get asked a lot.

And that I asked Dr.

Matthew Walker when he was a guest on this podcast,

here was his answer.

And here’s what the data support.

It is fine to nap in the afternoon,

but don’t nap so late in the day or for so long that it

disrupts your ability to fall and stay asleep at night for

your major sleep bout. Okay.

So naps are fine,

but don’t sleep so long during the day or too late in the

day that it disrupts your ability to fall and stay asleep.

I should also say you do not have to nap.

It’s kind of an interesting phenomenon that happens on

these podcasts and on social media,

where we’ll talk about naps and the fact that naps are

great and don’t make them longer than 90 minutes,

but then all the non-nappers get really worried.

Like, wait, am I supposed to nap? I don’t like naps.

I wake up groggy. You do not have to nap.

In fact, if you can make it through your whole day without

napping, great, more power to you.

But if you do nap and you find that naps serve you well,

keep those naps shorter than 90 minutes for reasons related

to ultradian cycles and so forth,

and make sure that you don’t nap too late in the day that

you are then staying up too late at night and having a hard

time waking up the next morning.

I will say that for a lot of people who do not like naps or

that find they wake up really grumpy from naps or groggy

from naps, I encourage you to try the Reverie app,

try an NSDR script, try yoga, Nidra,

try something of that sort for anywhere from 10 to 20 to 30

minutes. I tend to do this every day.

Now I’ll just lie down and I love yoga, Nidra.

I love NSDR scripts.

I love using the Reverie app in particular,

the portion of the Reverie app that gets you better at


It really is beneficial for me because it serves as very

replenishing while I’m doing that hypnosis,

but it’s also gotten me much better at falling and staying

asleep and falling back asleep in the middle of the night.

So this critical period throughout the day is one in which

most people are doing a lot of stuff.

They’re emailing and picking up kids and they’re exercising

and they’re commuting and doing all sorts of things,

taking phone calls and zooms, et cetera.

But if you can get that period of deep relaxation through a

nap or NSDR, that’s going to serve you well,

try not to drink too much caffeine,

certainly no more than a hundred milligrams of caffeine after

4 p.m. if your goal is to fall asleep at a reasonably normal


And for those of you that exercise in the afternoon,

understand that if you exercise very intensely,

so this might be weight training or running or some other

very intense exercise,

typically that’s going to further increase your body


It makes sense, right?

Based on everything we know about metabolism and body


and it’s going to so-called delay your circadian clock.

It’s going to make it such that you want to fall asleep a

little bit later, maybe even a lot later.

So if you’re exercising in the afternoon or evening,

and that’s the only time you can exercise,

or that’s the time that you prefer to exercise great,

but be careful about ingesting too much caffeine in order to

get the energy to do that exercise.

Cause that caffeine will disrupt your sleep and just know

that you are delaying your circadian clock.

You are making it such that you will naturally want to go to

sleep later and wake up later.

Contrast that with, if you exercise early in the day,

say immediately after waking up or in the first zero to four

hours after waking in most cases,

that’s not going to shift your circadian clock much.

And toward the end of the episode,

we’ll talk a little bit about forced exercise prior to wake

up times.

That doesn’t mean doing exercise in your sleep.

That means deliberately setting alarm and getting out of

bed much earlier than you naturally would.

That turns out to be a very potent tool to so-called advance

your circadian clock.

So we can talk about that a little bit later in the episode,

but this critical period two in the middle of the day is

when you’re going to want to leverage specific tools.

And we talked about those limiting caffeine intake,

being mindful of the clock delaying effects of exercise.

The fact that also, if you’re going to nap,

you don’t want to nap too long or too late into the day.

Otherwise you’ll disrupt your nighttime sleep.

So this critical period two or second critical period,

I should say during the middle of the day is a time in which

you should be doing certain things and avoiding doing

certain things.

So that raises the question of whether or not you should also

be getting a lot of light in particular sunlight throughout

the day.

Now that’s something that hasn’t been explored too much in

the literature until recently when Dr. Sam Rathar,

who’s the director of the chronobiology unit at the national

institutes of mental health has decided to do a number of


exploring the effects of light on mood and other aspects of

brain function and body function.

When that light is delivered, not just in the morning,

which is great for us, but also throughout the day.

So should you be looking at sunlight or bright artificial

lights throughout the day?

Now on the face of it, you might just think, yes,

you know, sunlight’s great,

provided we’re not getting a sunburn and we’re not staring at

the sun and damaging our eyes.

We should get as much sunlight as we possibly can.

In fact,

we talked about this in the episode on hormones,

about how getting light onto as much of our skin as we can

throughout the day can really help in the production of

testosterone and estrogen in both men and women and healthy

ways that improves mood and libido and all sorts of things

that are associated with wellbeing.


because light is such a powerful stimulus for controlling

the timing of your sleepfulness or sleepiness,

I should say, and wakefulness,

we might want to be cautious about how much light we are

viewing in the afternoon,

in particular in the early evening hours, right?

Well, it turns out it’s not so straightforward viewing.

So sunlight to the eyes,

sunlight in the late afternoon and evening hours.

So again, depends on time of year,

depends on location that you happen to be in,

but getting some sunlight in your eyes for, again,

maybe five or 10, maybe 30 minutes,

depending on how much cloud cover there is,

doing that in the afternoon serves an additional beneficial


which is you protect or you inoculate your nervous system

against some of the negative effects of bright artificial


or even dim artificial light in the nighttime hours between

10 PM and 4 AM,

which is really critical period three.

And we’ll talk about what to do and what to not do during

critical period three of every 24 hour cycle.

But to make it very clear what I’m saying here,

get that morning sunlight in your eyes,

but also get some sunlight in your eyes in the late

afternoon and evening hours,

when the sun is at so-called low solar angle,

when it starts to descend in the sky, again,

you don’t have to stare directly at the sun,

although if you can catch a nice, beautiful sunset,

go for it.

But as the sun starts to descend,

it triggers those same neurons in your eye that communicate

with your circadian clock,

but it communicates with a different component or different

compartment within the circadian clock.

That circadian clock is not just one thing.

It’s multiple things.

And you have what are called morning oscillators and evening


And to make a long story short,

the tool that I’m describing of looking at the sun in the

late afternoon and evening, again, blinking is fine.

Don’t stare at the sun,

but getting that sunlight in your eyes in the late afternoon

and evening signals to that clock that it’s evening time and

that sleep is coming.

It also serves as a second anchor or reference point for

your body and your brain to know where it is in time.

Remember back to the beginning of the episode when I said

your brain and your body and all your organs are locked

inside this skin and the skull,

and they don’t know what’s going on in the outside world.

Well, that morning sunlight viewing and the other things you

do during critical period one,

those provide one strong set of signals that it’s wake up

time and time to be alert and time to be focused.

And then in the evening,

by getting sunlight in your eyes again,

and in particular sunlight that comes from low solar angle

sunlight, well,

that provides a second stimulus or a second reference point

that tells your brain and body, Hey, it’s evening.

The sun is descending.

And you might say, wait,

how does the brain and these neurons know the difference

between morning light and evening light?

It turns out has to do with the particular wavelengths of

light that are present in morning versus evening.

It’s an incredible mechanism.

And you are probably familiar with the fact that when the

sun is directly overhead, it’s really bright,

white and yellow, and the sky is often blue.

And if there’s cloud cover,

it just comes through as a bunch of bright light.

Well, next time you’re out in the morning,

take a look at what a sunrise looks like.

There’s a lot of yellow, blue contrast,

and those yellow blues signal important specific sets of

cells in your eye and brain that it’s morning in the evening.

You’re also going to see yellow and blue,

but the ratio of yellows and blues has now changed.

And you also see some oranges and in a really brilliant

sunset, you’ll see some reds.

If you haven’t noticed this already,

you’ll really want to look for this.

It’s like kind of fun and cool to look at.

Well, those yellows and blues and oranges that you see in the

evening sunsets, those signal to your brain and body,

that evening is there and that nighttime is coming.

And they’re really establishing a second reference point or

wave front of biological signals that are going to optimize

your nighttime hours and your transition into really

terrific sleep.

So now let’s talk about what I’m calling critical period

three of each 24 hour cycle.

So this would be the period of time of late evening.

So it might be 6 PM for some,

depending on when you go to sleep or 7 PM extending into the

hours in which you decide to get into bed and go to sleep.

And then throughout the night,

there are a number of things that you’re going to want to do.

And there are a number of things that you are going to want

to avoid doing in order to optimize your sleep.

First of all,

you’re going to want to avoid bright artificial lights of

any color. Yes. Of any color.

We haven’t talked a lot about blue blockers, you know,

lenses that block blue wavelengths or short wavelengths of

light. I don’t have anything against blue blockers.

In fact,

many people find that blue blockers provide them some relief

from headache and some eye strain if they wear blue blockers

throughout the day and certainly at night,

but you don’t need them.

And even if you do wear them,

you will find that if lights are very bright,

doesn’t matter if it’s a blue light,

a yellow light or a red light,

those bright lights will wake up your brain and body.

They will activate the same mechanisms that were activated

early in the day by sunlight.

However, and here’s the really diabolical twist.

I mentioned this earlier,

but the diabolical twist in the way that your brain and body

respond to light is that early in the day,

in the morning hours,

you need a lot of bright light,

ideally from sunlight to be very alert and to wake up.

But in the evening hours and nighttime hours,

it takes very little light,

very few photons in order to wake up your brain and body and

to disrupt your circadian clock and disrupt your sleep.

So what that means is that once the sun goes down,

which of course is going to happen at different times of

year in different places on earth.

But once the sun goes down,

you would be wise to try and dim the lights in your indoor

environment most days, right?

I realized some nights you’re going to throw a party and

have people over.

You might not want to dim the lights.

Some nights you’re going to go out.

You might view a lot of bright lights,

but most nights of your life,

you’re going to want to dim the lights in your internal


And ideally the lights that you do use,

you would place low in that physical environment.

So you would try and not use overhead lights,

but rather rely on desk lamps or lights,

even place low to the floor, even on the floor.

If you are going to use light at night, and most people do,

I would encourage you to use as little artificial light as

is required to carry out the activities you need to require


That could be studying in which case you might need a

little bit more light in order to read or study.

If you’re watching a television show or you’re watching

something on your computer, dim that screen way,

way down as dim as possible while still, of course,

being able to view what you need to view.

Even better, I should say,

ideally you would use candlelight and or moonlight.

Now some nights the moon is really bright and you actually

can use moonlight to go about your usual activities.

Moonlight might seem very, very bright,

but actually moonlight is fairly low light intensity and

candlelight, which can also seem very bright,

actually is very low light intensity.

If you’re sitting across the table with some candlelight

there and it’s a really bright candle,

chances are it’s only about three to 10 Lux,

which is very, very little light energy compared to say an

artificial desk lamp or an overhead light,

which is going to be in the area of anywhere from a hundred

to a thousand Lux.

So candlelight is fine, of course,

be cautious with open flame, but candlelight is fine.

Moonlight is fine.

Dimming artificial lights is fine,

provided they’re dimmed way, way down.

And again,

try and avoid using overhead artificial lights.

The absolute worst lights are going to be overhead

fluorescent lights of the sort that you would have in the

supermarket or that you would see at a gas station or

something of that sort.

And I confess there are times in which I’m, you know,

driving home and it’s late at night and I want to be able to

get to sleep and I’ll need to stop at the grocery store or a

gas station or something like that.

I’ve actually put on sunglasses at night in order to avoid

getting that bright light exposure at night.

Although that’s a little bit extreme.

I have done that from time to time because that bright light

exposure will absolutely quash.

It will eliminate any melatonin that happens to be

circulating in your brain and body.

Now, melatonin, a lot of people think of as a supplement,

but melatonin is naturally released as the evening comes

about and into the nighttime hours,

it’s a hormone that makes you feel sleepy and allows you to

fall asleep.

So viewing bright light in the late evening hours and

nighttime hours is really not good for your sleep quality

and your ability to fall and stay asleep.

So for most people,

a simple rule of thumb is going to be avoid bright

artificial lights of all colors.

And in particular overhead,

bright artificial lights between the hours of 10 PM and 4

AM. That’s right between 10 PM and 4 AM,

avoid those bright artificial lights as much as possible use

only as much light as is absolutely necessary in order to

carry out the routines and activities you need to carry out


I should mention that the reason overhead lights are

problematic is the same reason why sunlight is so great

early in the day, which is that the cells that is the

neurons that can wake up your brain and body through

activation of the circadian clock reside mainly in the

bottom half or two thirds of your neural retina.

And the way the optics of your eyes work is that the cells

on the bottom half of your eye view the upper visual field.

So this is a beautiful adaptive mechanism that allows these

cells to respond to overhead light from sunlight in the

early part of the day and throughout the day.

But in the evening,

if you have bright artificial lights on in those bright

artificial lights or overhead lights,

it’s going to more closely mimic what sunlight does in the

evening time.

And that turns out to be a bad thing.

If your goal is to eventually go to sleep.

So again, do like the Scandinavians do use lights that are

set low in the room at night.

And if you really want to optimize your sleep-wake cycles,

I suppose you could also do the opposite throughout the day.

You could really emphasize the use of bright artificial

lights and sunlight that comes from above.

And of course, sunlight always comes from above,

but if you’re working in a given, you know,

office environment and you know,

it’s 2 PM or 3 PM and you want to be as awake as possible,

really crank up the overhead lights.

And then in the evening is,

which is this critical period three that we’re referring to

really try and dim those lights or have them off or just

rely on candlelight or moonlight from the hours of about 10

PM until 4 AM.

Our good friend, Samer Hattar,

who’s been on this podcast before.

Samer is director of the chronobiology unit at the national

institutes of mental health.

Well, he’s absolutely obsessive about this light stuff and

avoiding light at night.

In fact, he lives in what I joke is like a cave at night from

9 PM until 5 AM, which is really his kind of sleep cycle.

He has his house so dark that you’d be lucky to be able to

find a spoon in the kitchen.

In fact, you’d be lucky to find your way down the hallway if

you’re me, but in any case,

dim the lights from them way, way down.

It will serve you well.

It will make it much easier for you to get sleepy and stay

sleepy and fall asleep and stay asleep throughout the night.

Now not to depart from this critical period three,

but if you recall viewing that afternoon light, right?

The low solar angle light as the sun is heading down in the


So it could be sunset or what I call circus sunset around

sunset while doing that is going to slightly,

but not completely offset any of the negative effects of

viewing artificial light at night.

So I don’t want to give people a pass here,

but let’s say you know that you’re going to watch some

Netflix at night, or you’re going to be up late studying,

and yet you still want to be able to fall and stay asleep.

Definitely make sure you see that evening light.

There’s a great study.

We’ll provide a link to this study,

which showed that if people view evening sunset light or

evening sunsets or sunlight right around the time of sunset,

it really serves to inoculate or offset some again,

some not all of the negative effects of artificial light

between the hours of 10 PM and 4 AM.

Now that’s light.

But as you recall,

we also have this tool related to temperature and you’ll

probably not going to be surprised that the way to leverage

temperature in the evening is the exact opposite of the way

that you want to leverage temperature early in the day,

early in the day,

temperature increases from cold showers or exercise, et cetera,

wake you up.

What that means is that taking a cold shower late at night is

probably a bad idea rather taking a nice hot bath or a


You might think would heat up your body.

And indeed that’s what happens if you stay in a very long

time, but if you do hot tub or a hot bath or a sauna in the


and you don’t stay in for more than 20 or 30 minutes and you

get out, you take maybe a cool ish shower or a warm shower.

Then what happens is there’s a compensatory cooling off of

your core body temperature for the reasons we discussed

earlier and your body temperature will drop by one to three

degrees and it will make it much easier to get into sleep.

So if you’re somebody that enjoys hot baths,

hot showers or hot tubs evening and nighttime is going to

be the best time to do that.

If your goal is to facilitate sleep.


you should try and make your sleeping environment pretty

cool, if not cold.

Now that doesn’t mean you need to be cold while you’re


You can get under as many blankets as you need,

but it’s a good idea to make your sleeping environment cool.

In fact,

drop the temperature in that sleeping environment by at least

three degrees.

And you’ll be happy that you did.


some people rely on things like eight sleep that I use that

one of these controllable temperature mattress covers.

Other people would simply do this by putting a fan in the

room or opening a window again,

depends on time of year, depends on technology,

depends on budgets, et cetera,

but you’re going to want to sleep in a relatively cool or

cold sleeping environment and then layer on the blankets as

needed to stay asleep.

And I say as needed,

because one of the things that you’re going to do in your


or if you happen to wake up is if you’re too warm,

you’re going to put a foot or a hand out from under those


And the reason for doing that is very logical.

Once you understand the mechanism,

you have special portals.

You essentially have ways of passing heat, excuse me,

in and out of your body,

primarily through the palms of your hands,

the upper half of your face and the bottoms of your feet

through so-called glabrous skin.

This was covered in the episode with Dr. Craig Heller from

the biology department at Stanford.

If you lower the temperature in your sleeping environment,

so lower the temperature in that room,

or use a controllable mattress cover that can cool down like

eight sleep or something of that sort.

It’s naturally going to make your sleep environment cooler.

And if you’re too warm under the blankets,

all you have to do is extend a hand or a foot out from under

those blankets.

Whereas if the sleeping environment that you’re in is too

warm, there’s very little you can do to cool off besides

push off those blankets.

So for instance,

if you’re too warm and you’re waking up in the middle of the

night, which is what happens if you get too warm,

you’ll push off those blankets.

But if the room is too warm, well, what are you going to do?

You’d probably have to put your hands into some cool water or

take a coolish shower or something for a couple of seconds.

That’s not very practical,

better to just keep the sleeping environment cool.

I’m not a big fan of people putting socks on while they

sleep, or I should say,

I’m not a fan of putting socks on while I sleep because that

eliminates this glabrous skin portal on the bottoms of one’s

feet. So for those of you that have heard, you know,

wear socks while you sleep,

that works great for people that tend to run too cold while

they sleep and wake up because their feet get cold.

But if you’re somebody who wakes up in the middle of the


you’re waking up because you’re getting too warm.

And the best thing that you could do is to cool or lower the

temperature in the room that you’re sleeping and not wear

socks, get under as many blankets as you need to fall asleep.

And then across the night,

you’ll naturally just move a hand or a foot or all hands and

feet out from under those blankets to cool off because of

the relationship between temperature and sleep.

That is dropping your core body temperature one to three

degrees gets you into sleep and helps you stay asleep.

So let’s say you do exercise late in the day and you’re

finding yourself very alert in the evening and you need to

fall asleep,

or let’s say you’ve exercised and you needed four cups of

espresso in order to do that exercise.


there are a few things that you can do to try and bring your

nervous system down into more state of calmness.

And you can do that also by lowering your core body


One of those I already talked about before taking a nice hot

shower or a hot bath,

and then getting out and cooling off will decrease your body


Maybe not enough to get you into sleep.

If you have a ton of caffeine in your system, but again,

you can use this mechanism of temperature shifts to wake up

or temperature shifts to fall asleep in ways that really can

help you overcome some of the, you know,

irregularities in your sleep-wake cycle and exercise cycle,

et cetera, because of course, nobody’s perfect.

Some days we end up having a workout in the afternoon,

or we’ll miss the workout entirely.

Other days we end up having that cup of coffee in the

afternoon with a friend,

and then we have a hard time falling asleep.

So you can use these tools,

not just in their optimized form, you know,

being absolutely obsessive and compulsive about exactly when

you do each of those tools, that would be wonderful.

But life happens as they say,

and some days you’re going to feel too alert at night and

you want to fall asleep,

or you got to get up especially early the next morning.

And you’re not somebody who normally goes to bed at 10 PM.

Well, that’s when something like a hot bath or a sauna can

really benefit you because it can adjust your temperature

rhythm accordingly.

I would be remiss if I didn’t touch on alcohol and CBD and


I always get questions about these.

And I should say, of course, many places, but not all THC is

illegal, although there are medical uses and some places

it’s decriminalized other places it’s legal.

Alcohol of course is consumed almost as frequently as

caffeine is consumed.

I personally don’t drink alcohol.

I don’t have anything against it per se.

I just don’t tend to enjoy it.

One of the reasons I don’t enjoy it is if I drink alcohol,

I’ve simply fall asleep.

So that doesn’t really accomplish any of the things that I

really want to accomplish because the sleep that one gets

after drinking alcohol is greatly disrupted sleep.

Hate to break it to you, but that’s the truth.

And when Dr. Matt Walker came on this podcast,

he said exactly the same thing.

While THC and alcohol do help some people fall asleep and

maybe even stay asleep.

The architecture of that sleep is suboptimal compared to the

sleep they would get without alcohol or THC in their system.

So I’m not here to tell you what to do or not to do.

I’m certainly not the substance police.

That’s not my role.

I’m just reporting to you the biology.

If your sleep is not restoring you to the extent that you

feel it should,

or if you are regularly relying on a drink or two in order to

fall asleep or THC in order to fall asleep,

that is disrupting your total pattern of sleep.

However, I do realize that nowadays,

a lot of people are relying on THC and or CBD,

especially edible forms in order to fall and stay asleep.

And, you know, we can just acknowledge the data.

It does seem that there’s a anxiety lowering effect of some

of those compounds that do help people who have a hard time

falling and staying asleep because of reasons related to


Although in a moment,

we’ll talk about some supplement and supplement protocols

that can also assist in the ability to fall and stay asleep

and that can adjust anxiety.

And that do not seem to disrupt sleep architecture in

negative ways.

And in fact,

can enhance the depth and quality of sleep architecture.


So you’ve done everything correctly up until now,

you got your morning routine from critical period one,

you got your afternoon routine.

You saw some sunlight in the afternoon.

You avoided caffeine in the eight hours or 10 hours before

bedtime. You’re not drinking alcohol.

You’ve cooled down the room.

You’re doing all these things, right?

You dim the lights, et cetera, et cetera.

What else can we do in order to optimize our sleep?

Well, I always say behavioral tools first,

then look to nutrition.

Then if necessary, look to supplementation.

And then if still necessary, look to prescription drugs,

obviously prescribed by a board certified physician.

Well, we’ve talked a lot about the behavioral tools for

critical period three.

We have not talked a lot about the supplementation based


There are supplements that for most people will greatly

improve their ability to fall and stay asleep.

And the three main supplements in that category or that kit

of sleep supplements,

and I’ve talked about these before are magnesium threonate.

So T-H-R-E-O-N-A-T-E,

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

and theanine, T-H-E-A-N-I-N-E, theanine.

Now, some important things to point out about magthreonate

as it’s called apigenin and theanine.

First of all, you don’t necessarily need to take all three,

although many people get a synergistic effect from taking

all three.

In fact, you may not even need to take even one.

What I recommend is that if you’re already doing all the

behavioral tools regularly and you’re still having trouble

falling asleep and staying asleep,

well then you might try one of the supplements within this

sleep stack.

They do have fairly wide margins for safety.

Although I should also say,

anytime you’re going to add or remove something from your

supplement protocol, your nutritional program,

you definitely want to talk to your physician.

I don’t just say that to protect us.

I say that to protect you.

But for most people,

the margins of safety on these things are going to be pretty

broad. A couple of notes about dosages.

For some people,

the dosages of any one or several of the supplements I

mentioned will be zero.

That is you won’t need them in order to get and stay asleep

most nights of your life.

That’s terrific if you don’t need them.

For many people, however,

taking 145 milligrams of magnesium threonate can be very


That’s the dosage that most people will benefit from.

Some people need to go a little higher.

Some people need to go a little bit lower.

One of the reasons that we’ve been pointing people towards

single ingredient formulations these days is because it

allows people to adjust the dosage of one component of a so

called sleep stack without having to disrupt the dosage of

another component and so on.

It also allows people to try just one element within the

sleep stack without having to purchase and try the others,

which is a problem if you’re buying a blend of a lot of

different ingredients.

So 145 milligrams of magnesium threonate,

50, five, zero milligrams of apigenin.

And again, you could just take the apigenin on its own.

And 100 to 400 milligrams of theanine taken again,

alone or in combination with the other supplements mentioned

in this stack,

many people find allows them to get really drowsy and fall

asleep, sleep really deeply.

And they feel much more refreshed the next day.

And they don’t have a grogginess to them.

Now, a couple of notes about these different supplements,

about 5% of people report that magnesium threonate really

disrupts their gut.

It gives them diarrhea or gastric distress,

in which case don’t take it.

If magnesium threonate disrupts your gut or your digestion

to a point where it’s uncomfortable or at all,

and you don’t like it, don’t take any of it.

The proper dosage for you, in other words,

would be zero milligrams.

Now in a slightly different way,

many people who can tolerate magnesium threonate or really

thrive on magnesium threonate and like apigenin might find

that theanine, even at the lowest dose of a hundred

milligrams, because again,

the range is a hundred to 400 milligrams that theanine gives

them such vivid dreams that they actually find it disruptive

or they wake up in the middle of the night,

or they find that the sleep that they’re getting is kind of

anxiety ridden because of the intensity of those dreams.

So some people might choose to leave theanine out of the

sleep stack and just take magnesium threonate or apigenin.

And again,

some people might leave magnesium threonate out of the

sleep stack.


all of this is really about finding the supplementation

protocol that’s ideal for you.

I should mention that whether or not you’re taking one or

two or three of the components of the sleep stack,

the ideal time to take those is 30 to 60 minutes before


especially if you haven’t had anything to eat for the three

hours or so before bedtime.

I confess that oftentimes I’ll have a little bit of a snack

late in the evening, some berries or something.

I try not to eat too close to bedtime,

but some evenings just because of work schedule,

I’ll get home late,

be 9 PM and I’ll eat a big meal.

And then I’ll take the sleep stack and fall asleep.

Every once in a while that just so happens.

Nobody’s perfect.

Certainly I’m not,

but that sleep stack can be very beneficial.

And I do think that it’s preferable to melatonin.

Here’s the reason.

First of all,

melatonin is a hormone that you endogenously make.

You now know a lot about melatonin and its control by light,

meaning light inhibits it or eliminates it.

Darkness promotes it and melatonin indeed can help us fall


But the dosages of melatonin that are contained in most

commercial products is far, far,

far greater than what we would make endogenously.

So it’s really supra physiological.

So that’s of concern because melatonin is not just

responsible for making us sleepy and fall asleep.

It also does things like interacts with other hormone

systems, testosterone and estrogen,

even in the puberty system and kids.

Is taking melatonin every once in a while,

a problem for adjusting to jet lag, et cetera, probably not.

I wouldn’t even say no,

but taking it chronically over time,

especially kids taking it chronically over time can

potentially be problematic.

So at least in my opinion,

these other supplements are going to be preferable to,

to melatonin.

Now, as I mentioned at the beginning of today’s episode,

there are some other things that I certainly take every once

in a while and that other people might consider taking in

addition to the sleep stack I talked about before,

or in place of that sleep stack,

if that sleep stack doesn’t work well for them.

So every third or fourth night,

I will take two grams of glycine and a hundred milligrams of

GABA in addition to the standard sleep stack that I talked

about before.

So I’m taking mag three and eight apogenin and theanine.

And then I will also take two grams of glycine and GABA,

which I find greatly enhances my ability to get into sleep.

But the reason I only add glycine and GABA every third or

fourth night is that if I take it too often,

I find that the entire sleep stack doesn’t work quite as

effectively. I don’t know exactly why this is the case,

but in any event, that’s what I do.

And more recently I’ve also started using inositol in

particular myoinositol every other night,

I’ll take 900 milligrams of myoinositol in addition to mag

three and eight apogenin and theanine and not on the nights

when I take glycine and GABA.

So I’m adding 900 milligrams of inositol to the standard

sleep stack of mag three and eight theanine and apogenin.

And what I find is not only does it greatly enhance my

ability to fall asleep quickly,

but if I wake up in the middle of the night,

which I often do to use the bathroom,

I find it very, very easy to fall back asleep.

Whereas when I don’t take inositol every other night or so,

I find that if I wake up in the middle of the night,

it’s a bit more of a challenge to fall back asleep.

So inositol has a number of different uses that have been

discussed in terms of mental health and in terms of

adjusting anxiety for its daytime use.

What I’m talking about is taking 900 milligrams of myoinositol

also 30 to 60 minutes before sleep,

along with the standard sleep stack.

And I found that to be immensely beneficial.

I also noticed that it has a pretty long tail of anxiety

suppression throughout the day.

And I’m not somebody who suffers from anxiety,

but I have to say it just has led me to feel a bit calmer

throughout the day.

And I don’t really know how to say this,

except in subjective terms to feel a bit more buffered

against or resilience against stress events.

And if you look at the literature on inositol and its

interactions with the serotonin system and other systems,

that all makes sense as to why that would be the case.

So we will provide links to our so-called sleep kit,

which is part of our neural network newsletter.

It’s a zero cost newsletter where you can access this

information about supplements and other behavioral tools for

sleep in list form.

But that sleep kit doesn’t include some of the newer

information that I’ve provided this episode,

in particular, the information about inositol

and what I’m finding to be the very beneficial use of

inositol for the ability to fall back asleep after waking up

in the middle of the night,

which is something that a lot of people struggle with.

Now that’s supplementation for falling and staying asleep,

but we can return to the behavioral tools also as powerful

levers and tools for falling asleep and getting back to

sleep. And again, we look to NSDR,

non-sleep deep rest or the Reverie app as a way to do that.

As I mentioned earlier,

the Reverie app has been developed on the basis of really

high quality peer reviewed research,

both clinical and non-clinical by my colleague,

David Spiegel,

who’s our associate chair of psychiatry at Stanford.

It’s a wonderful tool.

It does carry a cost after the initial seven day trial.

I can tell you what the,

what the cost on that is so you can get a sense because I do

realize that anything that carries a cost for some people,

it won’t be accessible right now Reverie.

And I should just mention they didn’t pay us for an ad read.

I’m just telling you what they told me so that I can

accurately report what, what it costs to use Reverie.

They have a monthly subscription to use the Reverie app at

  1. You do get the seven day free trial.

They have a yearly subscription of 99,

99, 99 with a seven day free trial.

And they have a lifetime purchase,

one-time purchase of 249 with no trial.

It right now is only available for Apple, not for Android,

but they are yes.

Going to have it available for Android soon.

There’s a signup list there.

I should mention that while the cost might seem high,

if you compare that cost to say supplements,

or you compare that cost to a poor night’s sleep over time,

the cost to at least to me seems somewhat modest.

I’m certainly within range for a number of people,

but I acknowledge not within range for other people,

which is why I also want to point to zero cost tools.

And the zero cost tool for getting asleep,

staying asleep and falling back asleep is going to be NSDR.

We’ll put a link to a non-sleep deep rest protocol

that’s available on YouTube.

So available to anybody, zero cost,

provided you have a internet connection.

Again, dim the screen,

if you’re going to turn that on late at night.

And there are a number of other yoga nidra scripts and apps

and sources around the internet in particular on YouTube

that are zero costs that you could use

if the Reverie app is outside your price range

or is not preferable to you, et cetera.

When I wake up in the middle of the night,

it’s usually to use the restroom.

I’ll go use the restroom.

We’ll keep the lights as dim as possible.

I’ll get back into bed.

And if I find that it’s easy to fall asleep, great.

I’m asleep.

And if not, then I will generally plug in the Reverie app.

They have a fall back asleep hypnosis

and 99 times out of a hundred,

I’m back asleep within minutes

and I don’t wake up until morning.

Now, very briefly, I just want to touch on some tools

that are very commonly used by many people out there.

And believe it or not,

there is peer reviewed science on things like eye masks.

Do eye masks improve your ability to stay asleep?

And indeed they do, provided they are not too tight

and provided that the room is cool enough.


Well, eye masks cover the upper half of your face,

which is where glabrous skin is localized.

Remember palms of the hands, bottoms of the feet,

glabrous skin on the face.

So a lot of people who wear eye masks will wake up

because they’re too warm if the room is too warm.

So if you’re going to use an eye mask to keep light out,

definitely make sure the room and your sleeping environment

and your bed are cool enough

in order for you to stay asleep.

In addition, I get a lot of questions

about earplugs.

Here’s the deal with earplugs.

Some people find that earplugs are very beneficial

because of course they prevent the entrance of sound

into the ear that could wake us up.

But some people find that the sound of their own beating

of their own heart can be disruptive.

And they get a sort of humming in their head

when they have those earplugs in.

I’m one such person, although I have family members

that like using earplugs when they sleep.

So it’s really up to you.

You have to see whether or not those earplugs

help or disrupt your sleep.

For me, they’re no good.

For some people, they really enjoy them.

I don’t use an eye mask

unless I’m sleeping in a really bright environment

or I need to sleep on a plane and things of that sort.

Other tools that I’ll just mention

that have peer-reviewed research to support them,

elevating your feet either with a pillow

or by elevating the end of your bed

by about three to five degrees

can be really beneficial for increasing the depth of sleep

because of the so-called glymphatic washout.

This is the movement of and circulation of fluids

in your brain at night that lead to more wakefulness

and actually can improve cognitive function

and a number of other things related to brain health.

There’s one caveat to that

for people that suffer from acid reflux,

having your ankles elevated above your chest

or above your heart in the middle of the night

can actually exacerbate that acid reflux.

You want to do the opposite.

You want to actually elevate the head side of your bed

by about three to five degrees.

Now, one of the common causes of sleep disruption

that has tremendously detrimental effects

is so-called sleep apnea.

So this is basically bouts of suffocation

or lack of oxygenation during sleep.

This is particularly the case

for people that are very heavyset

and that heavyset could be from obesity.

It could also be heavyset from having too much muscle.

A lot of people who are carrying too much muscle

will actually have sleep apnea without realizing it.

Sleep apnea is actually very dangerous.

It’s associated with a number of cardiovascular issues.

It’s associated with sexual dysfunction.

It’s associated with issues with cognition.

Sleep apnea is bad.

A lot of people will have to use the PAP,

which is a, it’s a device.

It looks like a sort of like a snorkel mask or dive mask.

It’s a whole apparatus that people go to sleep with.

However, many people can relieve themselves of sleep apnea

provided it’s not too serious and can sleep much better.

In fact, I think all people can sleep much better

if they train themselves to be nose breathers

while they sleep.

There are a lot of reasons to be a nose breather

unless you are breathing very hard due to exercise

or talking or eating.

That was all covered in James Nestor’s book,

Breath, The New Science of a Lost Art.

It’s been covered in a number of different podcasts.

We’ve talked about it on this podcast as well.

It’s a good idea to be a nose breather

unless you need to mouth breathe.

And it’s a great idea.

It’s a superb idea to be a nose breather in sleep.

And one way to really get good at that

is to take a little bit of medical tape

and to tape your mouth shut before going to sleep.

You heard me right.

Put some medical tape over your mouth

and force yourself to nose breathe during sleep.

It also prevents snoring in most cases,

really offset sleep apnea.

Sleep apnea, again, being a very serious health concern.

I should also mention as a tool

that if you have a hard time being a nose breather in sleep,

you can try doing your cardiovascular exercise,

at least the lower intensity cardiovascular exercise

through purely nasal breathing.

And one way to do that, again, is to tape your mouth shut

or put a gulp of water in your mouth,

but don’t actually swallow that mouthful of water

or to use a mouthpiece or just deliberately

keep your mouth closed

and insist on breathing through your nose.

Most people find that

when they start doing cardiovascular exercise that way,

it’s really challenging at first,

but over time they actually can feel quite calm

and still can generate a lot of physical effort

purely using nose breathing.

The reason that doing nose breathing

during cardiovascular exercise

translates to being a nose breather during sleep

is that your sinuses actually can dilate their plastic

and over time, plastic meaning they’re malleable, that is,

and they can become wider.

You’re not going to get giant nostrils.

Don’t worry about it.

Your airways within your skull,

because that’s what the sinuses really are,

these little passages within the skull.

And of course, within the nasal passages will dilate

and will allow you to breathe more easily through your nose.

But for those of you that are waking up

in the middle of the night, breathing on your back,

or your partner is telling you that,

or other people are telling you that,

or that person on the plane with your mouth hanging open

and drooling and your mouth breathing.

Terrible, terrible, terrible for health reasons

and other reasons.

Put some medical take over your mouth.

Learn to be a nose breather during sleep.

Your sleep will improve

and your daytime feelings of wakefulness

and focus will improve.

Your cardiovascular health will improve

and on and on and on.

So now we’ve largely covered the tools

that one could use to get and stay asleep.

And we talked about exercise.

We talked about temperature.

We talked about supplements.

And we talked about, of course,

keeping the sleeping environment both cool

and as dark as possible.

I do want to mention a couple of broad contour tools

that will impact your ability to sleep really well

on a consistent basis.

And the one that impacts the most number of people

is weekends.

Turns out that most everybody feels the impulse

to sleep in on the weekend,

especially if they’ve been out late the night before.

However, the data show

that keeping relatively consistent sleep and wake times

is really going to enhance the quality

and depth of your sleep.

So if you stay out late one night,

sure, you might allow yourself to sleep in

an extra hour or so,

but you should really try to avoid sleeping in longer

than an hour beyond your normal wake up time.

That’s right.

If you normally get eight hours of sleep

and you wake up at 7 a.m.,

probably okay to wake up at 8 a.m. on the weekend

or after a night out the night before,

but try not to sleep until 11 or noon

thinking that you’re going to catch up on your sleep

or that’s better than waking up at a consistent time.

It would be better to wake up at a consistent time

plus or minus an hour and get a nap in the afternoon

provided that nap, again, isn’t too long.

And the other tool that relates to nights

that you stayed out too late

or that you feel like you want to sleep in a bit more

in the morning is if you are going to wake up

at your consistent time.

So for example, normally you go to bed at 10

and you wake up at six.

Let’s say that’s your schedule

and you end up staying up late one night

until midnight or one for whatever reason.

And the next morning you wake up at seven

and you’re still groggy.

In that case, you absolutely want to wait

to ingest caffeine 90 to 120 minutes after waking.

You really do because there are good data

to support the fact that caffeine can disrupt sleep.

Yes, that’s obvious.

Caffeine especially disrupts sleep

if you take it too late in the day.

That’s very obvious as to why that would be the case.

But caffeine especially disrupts

what’s called compensatory sleep.

So if you start changing your waking time

and your to sleep time,

and you start using additional caffeine

to offset the sleepiness that you’re experiencing

because of those late nights out,

well, that’s when you really start to disrupt

not just your nighttime sleep

but your daytime compensatory sleep.

So those naps, you also are disrupting

the total architecture of sleep in the early morning hours.

There’s a lot of great science that’s been put to this

or that’s emerged from this, I should say.

So try and keep those sleep-wake times relatively constant

plus or minus an hour.

And try as much as you can to delay that caffeine intake

90 to 120 minutes after waking every day,

but especially on days where you wake up

and you feel you haven’t gotten enough sleep.

In that case, I highly recommend you just use NSDR

or the Reverie app or some other form of deep relaxation

to try and compensate for the lack of sleep.

Knowing of course,

that there’s no complete compensation for lack of sleep.

There are just things that we can do

to partially offset lack of sleep.

Now, a couple of final points

and additional tools that I think are going to be useful

to everybody, in particular, people who have young children

or following a shift work schedule

or who are experiencing jet lag.

Keep in mind, jet lag can be due to travel,

which is obvious, but jet lag can also be due

to getting woken up in the middle of the night, right?

Your body doesn’t know the difference

between flying to a new time zone

and getting woken up in the middle of the night.

The tool that I’d like to offer you is an understanding

of something called temperature minimum.

And I’m going to make this as simple as possible.

And I’m confident that everyone can understand this,

even if you don’t have any science background.

Here’s the question you need to ask yourself.

What is your typical wake-up time?

Okay, what’s your typical wake-up time?

If for you, your typical wake-up time is 7 a.m.,

plus or minus half an hour.

So, and that could be 7 a.m. because you set an alarm clock

or it could be 7 a.m. because you naturally wake up

at 7 a.m., doesn’t matter.

If your typical wake-up time most days is 7 a.m.,

well, then your temperature minimum is 5 a.m.

That’s right, your temperature minimum is not a temperature,

it’s a time within your 24-hour cycle.

Approximately two hours before your typical wake-up time,

your body is at its lowest temperature

that it will ever be in the 24-hour cycle.

That’s why it’s called your temperature minimum.

Here’s what you need to know about your temperature minimum.

If you view bright light, exercise, or drink caffeine,

or all of the above in the two to four hours

before your temperature minimum, that will delay your clock.

What that means when I say delay your clock

is it will make you want to go to sleep later

and wake up later the next night.

Okay, so let’s run this exercise for you,

the person waking up at 7 a.m. on a regular basis.

I can predict with almost certainty that your body

is going to be at its lowest temperature at 5 a.m.

So what that means is that if you get up at 3 a.m.

or at 4 a.m. and you flip on bright lights in your house

or in your bathroom, or you have a cup of coffee,

or you do any kind of exercise,

or you get up and head to the airport,

the mechanisms in your brain and body that control timing

of sleep and timing of waking will shift, they will delay.

It’s as if you put your clock on hold for a little while

and then let it start again.

Okay, that’s the simplest way I can describe it.

And you will tend to want to go to sleep later

and wake up later the following night.

Now, the opposite is true if you view bright light,

drink caffeine, or exercise, or socialize, I should say,

in the hours immediately after your temperature minimum.

So for you, in this example,

the person who’s waking up at 7 a.m.,

your temperature minimum is 5 a.m.

If you view bright light, exercise, maybe have a snack,

maybe not, or socialize, move about at 5.30 or 6 a.m.

or 7 a.m., that will tend to phase advance your clock.

It will tend to basically make you want to go to bed earlier

and wake up earlier the following night.

Now, I use this example of a person who wakes up

typically at 7 a.m., whose temperature minimum is 5 a.m.,

but of course you need to adjust that for yourself

if you’re somebody who wakes up at 9 a.m.

or at 5 a.m., et cetera.

Why do I offer this as a tool?

Well, this is an immensely powerful tool if, for instance,

you’re headed to a time zone

where you need to go to bed earlier

and wake up earlier once you arrive in that time zone.

What it means is in the day or two before you leave,

you can force yourself to exercise, drink caffeine,

maybe even to eat a meal early in the morning,

or maybe you still fast early in the morning,

and that’s really up to you,

but you force yourself to do the activities

that are going to phase advance your clock.

Whereas if you’re traveling to a time zone

where you are going to need to go to sleep much later

and you’re going to need to wake up much later,

or even a little bit later,

you can do those things in the hours

prior to your temperature minimum.

Now, for those of you that work shift work,

this can be especially useful,

but I want to say a couple of things about shift work.

There are a lot of details about shift work and jet lag

in an episode that I did specifically

about jet lag and shift work,

so for the deep dive, go there,

but suffice to say this for now.

If you are going to do shift work,

try to stay on the same shift for two weeks at a time.

It’s very detrimental to brain and body.

It can even be horrifically challenging

for your brain and body in a number of ways.

If you are switching on the so-called swing shift,

you know, you’re working three days, the night shift,

three days, the day shift, three days, the night shift,

three days, try and stay on the same schedule

as much as possible.

And I should say for everybody,

people who are jet lagged and engaged in shift work or not,

but just for everybody,

if you need to be awake in the middle of your sleep cycle,

and it’s not just a quick departure to the bathroom

and back to bed, but you really need to be awake,

you know, you’re feeding a baby

or you’re taking care of a loved one

or you need to do something that’s critical

or you need to work, if possible, use red light, okay?

Now for shift workers who really are trying

to stay awake all night and sleep all day,

this is not going to be ideal.

But for people that, for instance,

need to stay up really late one night

or wake up especially early,

like 3 a.m. to prepare for an exam

that you’re just not ready for

or to head to the airport, et cetera.

Using red light has been shown to allow people

to be awake enough and obviously see what they need to see

in order to perform their activity safely.

But it does not seem to disrupt the cortisol rhythm

that is the healthy, normal cortisol rhythm.

I realize this is kind of an advanced tool

and many people won’t have access to this.

There are a number of different sources for red lights now.

Companies like Juve or Cozy Light,

these are different brands.

I don’t have any affiliation to any of these brands,

I should say.

There are a number of different red light bulb sources

out there and commercial sources

that you can explore if you want.

But understanding this temperature minimum

is really powerful because it allows you

to adjust your schedule depending on travel,

depending on changing work schedules or school schedules.

And if you’re not a morning person,

you can use the tools related to temperature minimum

to really become a morning person over time.

And it actually is pretty easy.

And I talked about this in a previous episode,

I’ll just mention that there have been shown

to be important positive effects on cognition,

on even grip strength and physical performance

for people that are early morning risers.

And that’s especially true for night owls

that deliberately shift themselves to become early risers.

Okay, so that’s a lot of information and a lot of tools.

And I suppose the one set of tools

that I really didn’t drill into too deeply,

the ones related to jet lag and shift work.

And again, please check out the episode

on jet lag and shift work if that’s relevant to you.

But I think for most people who are going to sleep at night

and are trying their best to sleep well at night

and are trying their best to wake up in the morning

at whatever hour and stay alert and focused

throughout the day, maybe with a brief nap,

the tools that I talked about today related

to light temperature, food, exercise, caffeine,

supplements, and digital tools,

I’m hoping will prove to be very useful for you.

They certainly are all supported

by excellent peer-reviewed research.

And I should just emphasize again

that most of the tools we talked about

are completely zero cost.

So while the supplements and some of the digital tools

do carry some costs to them,

I really want to encourage everybody

to get your behaviors right.

Get all of the things related to your timing of exercise

and type of exercise in the best possible order

and time of day.

We talked about this critical period early in the day

and then another critical period in the middle of the day

and the late afternoon,

and then this third critical period

in the middle of the night.

Different tools for the different three critical periods.

I promise that if you start to implement some

or ideally all of these tools,

the quality of your sleep will increase tremendously.

And of course, in doing so,

the quality of your daytime alertness

and your ability to focus will improve tremendously.

Again, sleep is the absolute foundation

of your mental health, your physical health,

and your performance in all endeavors.

So if there’s one area of your life to really focus on

and try and optimize,

if your goal is to be happier and more productive

and just to have a better life overall,

I can confidently say that sleep

is really the thing to optimize.

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While supplements aren’t necessary for everybody,

many people derive tremendous benefit from them

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So thank you for joining me today

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And in doing so, tools for optimizing not just sleep,

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