How to Defeat Jetlag, Shift Work & Sleeplessness

00:00:00.160 | - Welcome to the Huberman Lab Podcast,

00:00:02.360 | where we discuss science and science-based tools

00:00:04.960 | for everyday life.

00:00:05.980 | I'm Andrew Huberman,

00:00:10.720 | and I'm a professor of neurobiology and ophthalmology

00:00:13.840 | at Stanford School of Medicine.

00:00:16.000 | This podcast is separate from my teaching

00:00:17.840 | and research roles at Stanford.

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00:00:23.240 | about science and science-related tools

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00:02:50.920 | Today's podcast episode is about sleep

00:02:53.520 | and wakefulness.

00:02:54.920 | We are going to discuss jet lag, shift work,

00:02:59.000 | babies, kids, and the elderly.

00:03:01.460 | And we are going to discuss protocols

00:03:03.680 | that are backed by science.

00:03:05.660 | That means quality peer-reviewed papers published

00:03:07.840 | in excellent journals that can support particular tools

00:03:12.200 | that you can use to combat things like jet lag,

00:03:15.520 | offset some of the negative effects of shift work,

00:03:17.960 | and make life easier for the new parent

00:03:21.000 | as well as for the newborn child, the adolescent,

00:03:24.580 | anyone that wants to sleep better,

00:03:27.180 | feel better when they're awake, et cetera.

00:03:30.120 | If you've listened to the previous three episodes

00:03:32.440 | of the Huberman Lab Podcast,

00:03:34.040 | we've been exploring these themes of wakefulness

00:03:37.640 | and sleepiness, how to fall asleep, how to stay asleep.

00:03:40.960 | And we've been discussing parameters like light,

00:03:43.860 | exercise, temperature, et cetera.

00:03:47.500 | If you've had a chance to listen to those episodes, great.

00:03:50.260 | Today's discussion will be even more digestible for you.

00:03:55.220 | If you haven't, that's okay.

00:03:57.180 | I will provide a little bit of background here or there

00:03:59.380 | so that it's not necessary that you have listened

00:04:02.420 | to those previous episodes.

00:04:03.660 | But if you get a chance to listen to them, please do it.

00:04:07.180 | I think it will help you digest the information better.

00:04:10.580 | Let's just take a step back for a moment

00:04:12.940 | and remind everybody what we're talking about.

00:04:15.460 | We're talking about an endogenous,

00:04:17.820 | meaning within us, rhythm that we call the circadian rhythm.

00:04:21.820 | The circadian rhythm is a 24 hour rhythm

00:04:25.200 | in all sorts of functions.

00:04:28.300 | The most prominent one is a rhythm

00:04:30.740 | in our feelings of wakefulness and sleepiness.

00:04:34.240 | So believe it or not,

00:04:35.860 | the experiment has been done throughout history,

00:04:38.340 | not often, but it's been done where people will go down

00:04:40.700 | into a cave and will exist in constant darkness

00:04:43.820 | for some period of time.

00:04:45.520 | There are also cases where people have been

00:04:46.860 | in constant light for some period of time.

00:04:49.340 | But because people can close their eyes,

00:04:51.100 | it's actually easier to do the experiment

00:04:53.160 | where you're in constant darkness

00:04:54.580 | to address the question of what is the endogenous,

00:04:57.280 | meaning the internal rhythm that we all have.

00:04:59.700 | And it turns out we all have this rhythm of about 24 hours,

00:05:03.380 | although it's not exactly 24 hours.

00:05:05.140 | Meaning every 24 hours,

00:05:08.300 | your body temperature goes from low to high

00:05:11.420 | and back down to low again.

00:05:13.000 | And it takes 24 hours for that to repeat.

00:05:15.060 | Not 18, not six, 24, plus or minus a couple hours.

00:05:19.620 | You also have a rhythm in sleepiness and wakefulness

00:05:23.820 | that correlates with that.

00:05:24.760 | We tend to be sleepy as our temperature is falling,

00:05:28.240 | getting lower, and we tend to be more awake or waking

00:05:33.240 | when our temperature is increasing.

00:05:35.780 | This is a biological fact.

00:05:37.380 | It is right down to our DNA.

00:05:39.900 | We actually have genes in every single one of our cells

00:05:42.380 | that ensure that every cell is on this 24-hour-ish rhythm,

00:05:46.500 | close to 24 hours.

00:05:47.700 | We have a clock over the roof of our mouth,

00:05:52.140 | a group of neurons called the suprachiasmatic nucleus.

00:05:55.240 | That clock generates a 24-hour rhythm,

00:05:58.980 | and that clock is entrained,

00:06:00.740 | meaning it is matched to the external light-dark cycle,

00:06:04.920 | which is, no surprise, 24 hours.

00:06:08.100 | Spinning the Earth takes 24 hours.

00:06:10.500 | So our cells, our organs, our wakefulness, our temperature,

00:06:15.500 | but also our metabolism, our immune system, our mood,

00:06:21.700 | all of that is tethered to the outside light-dark cycle.

00:06:25.580 | And if we are living our life in a perfect way

00:06:29.000 | where we wake up in the morning

00:06:31.260 | and we view sunlight as it crosses the horizon,

00:06:34.620 | and then by evening, we catch a little sunlight,

00:06:38.300 | and then at night, we're in complete darkness,

00:06:40.980 | we will be more or less perfectly matched

00:06:43.180 | to the external or ambient light-dark cycle.

00:06:45.840 | Very few of us do that

00:06:48.780 | because of these things that we call artificial lights

00:06:51.740 | and this other thing that we call life demands.

00:06:55.060 | So today we're going to talk about

00:06:57.180 | when we get pulled away from that rhythm.

00:07:00.020 | Now, you may immediately be thinking,

00:07:03.260 | well, I've heard there are night owls

00:07:05.100 | and there are morning larks, they're sometimes called,

00:07:07.740 | and there are genetic polymorphisms,

00:07:09.540 | that's just a fancy name for genetic variations

00:07:12.020 | that make some people want to wake up early

00:07:13.560 | and other people want to stay up late

00:07:14.840 | and teens want to sleep in more.

00:07:16.440 | Sure, that's all true.

00:07:18.340 | That's all true regardless of what names we give those.

00:07:20.780 | However, there's no escaping the fact

00:07:23.580 | that human beings are a diurnal species.

00:07:26.140 | We were designed, literally,

00:07:28.680 | our cells and the circuits of our body

00:07:30.780 | were constructed to be awake during the daytime

00:07:34.220 | and asleep at night.

00:07:35.560 | How do I know that?

00:07:36.580 | Well, I wasn't consulted at the design phase,

00:07:39.140 | but I'm certain of that because many studies have shown

00:07:42.980 | that when we deviate too far from a diurnal schedule

00:07:47.300 | and we try and become nocturnal, we can pull it off,

00:07:50.700 | but serious health effects,

00:07:52.380 | both mental and physical, start to arise.

00:07:55.220 | I'm not going to spend much of today

00:07:57.020 | talking about all the negative effects of jet lag.

00:07:59.180 | I'll talk a little bit about it,

00:08:00.940 | or the negative effects of shift work,

00:08:02.580 | or trying to scare you by telling you

00:08:04.600 | about the quite valid data around depression,

00:08:09.600 | amnesia, dementia, all the terrible things that happen

00:08:13.940 | when you're not sleeping well.

00:08:15.020 | Rather, I'd like to focus on what you can do

00:08:16.840 | and arm you with tools.

00:08:18.620 | So let's talk about that perfect schedule for a moment,

00:08:21.800 | and then let's talk about jet lag

00:08:23.520 | and what jet lag really represents

00:08:26.160 | and how to push back on jet lag, shift your clock faster,

00:08:30.160 | and escape some of the severe bad things

00:08:33.520 | that can happen with jet lag,

00:08:34.880 | including just feeling miserable

00:08:36.660 | when you're traveling for work or vacation.

00:08:38.840 | So what is the perfect day?

00:08:41.020 | What does that look like

00:08:42.080 | from a circadian sleep wakefulness standpoint?

00:08:45.300 | I'm about to summarize what I've said

00:08:46.940 | in the three previous podcast episodes,

00:08:50.740 | as well as now countless Instagram posts.

00:08:53.580 | Here's the deal.

00:08:56.180 | You basically want to get as much light, ideally sunlight,

00:09:02.340 | but as much light into your eyes

00:09:05.060 | during the period of each 24-hour cycle

00:09:07.320 | when you want to be awake, when you want to be alert.

00:09:10.780 | And you want to get as little light into your eyes

00:09:14.400 | at the times of that 24-hour cycle

00:09:17.040 | when you want to be asleep or drowsy and falling asleep.

00:09:20.900 | How much is enough?

00:09:23.160 | Well, you don't want to go so high with the light exposure

00:09:26.640 | that you damage your eyes,

00:09:27.640 | because as many of you have heard me say before,

00:09:30.040 | the eyes are actually two pieces of your brain,

00:09:32.420 | your central nervous system

00:09:33.340 | that were extruded out of your skull.

00:09:35.080 | And as pieces of the central nervous system,

00:09:36.900 | AKA your brain, they will not regenerate.

00:09:40.260 | At least right now, the technologies don't exist

00:09:42.180 | to regenerate those neurons in humans.

00:09:43.600 | You do not want to damage them.

00:09:45.400 | So what is too bright?

00:09:46.780 | Well, when it's painful to look at.

00:09:49.360 | When you have to blink or close your eyes

00:09:50.720 | in order to bear it.

00:09:51.560 | So please don't look at very bright lights,

00:09:54.720 | so painful that they're likely going to damage your eyes.

00:09:59.400 | However, if you get up in the morning

00:10:02.480 | and it's still dark out and you want to be awake,

00:10:05.960 | you would be wise to turn on artificial lights,

00:10:09.320 | in particular overhead lights

00:10:10.560 | for reasons I've discussed previously,

00:10:12.080 | but those overhead lights will optimally trigger the neurons,

00:10:14.880 | these melanopsin cells in the retina

00:10:17.540 | that will activate your circadian clock.

00:10:20.180 | When the sun comes out, even if there's cloud cover,

00:10:23.800 | the sun does come out every day,

00:10:26.040 | regardless of where you live, unless you live in a cave.

00:10:29.440 | People have said to me,

00:10:30.280 | "Well, I live in an area where I can't really see the sun."

00:10:32.440 | Well, the sun is there.

00:10:34.160 | It might be hiding behind clouds

00:10:37.080 | unless it's very, very dark where you live,

00:10:39.060 | like Scandinavia in the depths of winter,

00:10:42.000 | which case you might want some artificial light.

00:10:44.220 | Get some sunlight in your eyes when you can.

00:10:47.000 | Here's the deal with sunlight and artificial light

00:10:49.920 | that I have not discussed previously.

00:10:53.360 | A lot of photon energy, a high amount of lux,

00:10:56.960 | L-U-X, comes through even cloud cover.

00:10:59.280 | A good number to shoot for as a rule of thumb

00:11:03.400 | is to try and get exposure to at least 100,000 lux

00:11:07.560 | before 9 a.m., 10 a.m. maybe, but before 9 a.m.,

00:11:13.420 | assuming you're waking up sometime between 5 and 8 a.m.

00:11:19.320 | So get 100,000 lux.

00:11:21.340 | Now you do not, I want to repeat,

00:11:23.080 | you do not want to stare at a 200,000 lux

00:11:25.940 | or a 100,000 lux light.

00:11:28.540 | It's very, very bright.

00:11:29.780 | The mechanism of circadian clock setting,

00:11:34.000 | and this is very important,

00:11:35.780 | the mechanism of circadian clock setting

00:11:37.780 | involves these neurons in your eye

00:11:40.240 | that send electrical signals

00:11:41.680 | to this clock above the roof of your mouth,

00:11:44.120 | and that system sums, meaning it adds photons.

00:11:47.960 | It's a very slow system.

00:11:49.760 | So let's say that I wake up

00:11:51.740 | and I look at my computer screen briefly or my phone screen.

00:11:55.660 | That's probably 500 to 1,000 lux.

00:11:57.800 | If I were to look at that for a full minute,

00:12:00.560 | I would get that photon energy

00:12:02.800 | transferred into electrical energy of neurons

00:12:04.820 | and it would be communicated to my circadian clock.

00:12:06.920 | However, the signal that it's morning

00:12:08.920 | will not have registered with the circadian clock

00:12:12.340 | unless I looked at that for 100 minutes or more.

00:12:17.000 | So 100,000.

00:12:17.880 | Now the problem is if you wake up at eight o'clock,

00:12:20.880 | you're not going to get enough light from artificial light

00:12:23.740 | before you reach what's called the circadian dead zone.

00:12:26.000 | So you have this opportunity before 9 a.m., maybe 10 a.m.,

00:12:29.920 | to capture enough photons

00:12:32.080 | and you have to do it with your eyes.

00:12:33.880 | I've discussed why that's important

00:12:36.400 | in previous episodes of the podcast,

00:12:38.000 | but you have to do it with your eyes.

00:12:39.320 | There is no extraocular photoreception.

00:12:41.520 | This is not about vitamin D in your skin.

00:12:44.240 | This is about setting your circadian clock,

00:12:46.400 | which is paramount for mental and physical health.

00:12:48.760 | So here we're talking about trying to get that

00:12:50.200 | at least 100,000 photons, but not all at once,

00:12:52.680 | but you got to get them before 9 a.m. ish, maybe 10 a.m.

00:12:56.300 | So what do you do?

00:12:57.140 | You go outside.

00:12:58.260 | If you want to get nerdy about this, quantitative,

00:13:01.200 | you could download a free app like Light Meter

00:13:03.780 | and take a look around your house with Light Meter

00:13:06.260 | and you'll notice that even bright overhead lights

00:13:08.840 | are only emitting about 4,000 or 5,000 lux.

00:13:13.200 | It's going to take a long while of looking at those lights

00:13:15.360 | with eyes open in order to set your circadian clock

00:13:17.800 | and tell your brain and body that it's morning.

00:13:21.000 | Going outside, even on a cloudy day,

00:13:23.500 | could be 7,000, 10,000 lux.

00:13:26.480 | It's really remarkable how bright it is,

00:13:29.020 | meaning how much photon energy is coming through.

00:13:30.960 | So try and get 100,000 lux before that 9 a.m.

00:13:34.840 | Now, if you can't do that because you live

00:13:36.640 | in an area of the world where it's just not bright enough,

00:13:40.380 | some people have sent me pictures from Northern England,

00:13:43.860 | it's just not bright enough in winter,

00:13:45.940 | then sure, you can resort to using artificial lights

00:13:49.840 | in order to get enough photons.

00:13:52.360 | And I'm putting out this 100,000 lux number as a target

00:13:55.800 | to get each day before 9 a.m.

00:13:57.620 | You can, in theory, get it all from artificial lights,

00:14:01.400 | but there are some special qualities about sunlight

00:14:03.460 | that make sunlight the better stimulus.

00:14:05.640 | First of all, it's free if it's available outside.

00:14:08.700 | There is a number of different, there are, excuse me,

00:14:12.920 | a number of different technologies,

00:14:14.120 | kind of like this one, like a light pad,

00:14:16.240 | that this one says it's a 930 lux.

00:14:18.840 | I'm covering this up 'cause I'm not trying

00:14:20.520 | to promote any specific products.

00:14:21.820 | I actually bought this just with my own money on Amazon.

00:14:24.760 | They're not a sponsor.

00:14:26.000 | And it lets you toggle the brightness,

00:14:27.520 | I think, by holding this on, holding down this button,

00:14:30.420 | you can make it dimmer or brighter.

00:14:31.760 | This is about 1,000 lux.

00:14:32.940 | It seems really bright, but a cloudy day outside

00:14:35.200 | will have five times more photon energy coming through.

00:14:38.060 | So some people set these lights or ring lights

00:14:41.820 | that they use for selfies and that kind of thing

00:14:43.480 | near their coffee or workstation first thing in the morning,

00:14:46.680 | but you really want to get sunlight, okay?

00:14:48.880 | So those things are kind of nice 'cause they'll travel

00:14:50.800 | and we're going to talk about jet lag,

00:14:52.800 | but I can't emphasize this enough.

00:14:55.280 | That light has to be captured and summed

00:14:57.440 | before you enter the circadian dead zone,

00:14:59.320 | which is the middle of the day.

00:15:00.840 | This is, again, trying to achieve kind of perfect schedule.

00:15:05.460 | Then I've recommended, based on scientific literature,

00:15:09.100 | that you look at sunlight sometime around the time

00:15:12.960 | when the sun is setting, and the reason for that, of course,

00:15:15.280 | is because it adjusts down the sensitivity of your eyes,

00:15:19.180 | because here's the diabolical thing.

00:15:21.700 | While we need a lot of photon energy early in the day

00:15:24.860 | to wake up our system and set our circadian clock

00:15:27.000 | and prepare us for a good night's sleep,

00:15:28.600 | 14 to 16 hours later, it takes very little photon energy

00:15:33.000 | to reset and shift our clock after 8 p.m.

00:15:37.080 | And that's why you want to, as much as you safely can,

00:15:39.920 | avoid bright light and even not so bright light

00:15:44.520 | between the hours of 10 or 11 p.m. and 4 a.m.

00:15:47.320 | A number of people have asked me some questions about this.

00:15:51.120 | In the last episode, I went into red lights,

00:15:53.120 | I went and discussed blue blockers, all that kind of stuff,

00:15:55.700 | so I'm not going to repeat all that.

00:15:57.280 | But here's the thing, if you see afternoon light,

00:16:01.400 | you're going to adjust down the sensitivity of your eyes

00:16:04.520 | so that you have a little bit more wiggle room,

00:16:07.960 | a little bit more leeway to view lights from screens

00:16:11.780 | and overhead lights even late at night

00:16:14.280 | without disrupting your circadian clock.

00:16:16.760 | But it is a kind of a double-edged sword

00:16:19.840 | where you need a lot of light early in the day

00:16:23.000 | and you need to avoid bright lights later in the day.

00:16:26.560 | I've mentioned studies on here.

00:16:27.700 | A number of you have asked about getting the references.

00:16:30.120 | We are in the process of trying to get a webpage going

00:16:32.580 | with full links.

00:16:33.420 | There's some copyright issues that we have to deal with,

00:16:35.880 | but wherever possible, I'll try and reference these studies.

00:16:38.500 | And when people ask, I'll generally put them

00:16:40.240 | in the response to their comments on YouTube or Instagram.

00:16:43.760 | There have been two studies done

00:16:47.580 | from the University of Colorado,

00:16:48.720 | both published in Current Biology.

00:16:50.500 | You can easily find these online

00:16:52.000 | by just googling the words current biology, camping,

00:16:56.120 | and reset circadian clocks that have shown

00:16:59.200 | that two days of waking up with the sun

00:17:01.920 | and avoiding light at night,

00:17:04.440 | they actually took graduate students camping,

00:17:06.380 | really cool experiment to be a part of,

00:17:08.080 | reset the melatonin and cortisol rhythms

00:17:10.320 | for these people that had otherwise drifted quite far

00:17:14.000 | from their natural rhythms.

00:17:15.360 | There are other things that you can do to shift your clock

00:17:19.220 | and to reinforce your clock,

00:17:20.440 | like exercising more or less the same time,

00:17:22.160 | eating more or less the same time, et cetera.

00:17:24.200 | That's not what today's episode is about.

00:17:25.640 | So I just described perfect schedule,

00:17:27.000 | get at least 100,000 lux of light exposure to the eyes,

00:17:30.420 | not all at once, but summing across the morning.

00:17:33.480 | Again, you know when it's too much

00:17:35.680 | because it's painful to look at.

00:17:37.240 | So that's obviously something to avoid.

00:17:40.080 | But then once the middle of the day,

00:17:42.040 | let's say you're waking up at 10 or 11,

00:17:43.500 | you go outside, the sun's overhead, forget it.

00:17:45.220 | You're not going to shift your clock.

00:17:46.760 | You're just not.

00:17:48.160 | It doesn't work that way.

00:17:49.400 | In the evening, you see the evening light

00:17:53.320 | and you want to get that light

00:17:55.680 | to adjust down your retinal sensitivity

00:17:57.640 | to afford you a bit of a buffer

00:17:59.600 | so that late at night,

00:18:00.800 | if you happen to look at screens

00:18:01.920 | or go to the bathroom in the middle of the night,

00:18:03.180 | it's not going to shift your clock

00:18:05.160 | because it takes probably only about 1,000 to 1,500 lux

00:18:10.160 | of light energy to shift your clock

00:18:12.120 | in the middle of the night.

00:18:13.080 | So let's talk about shifting clocks

00:18:14.560 | because for the jet lag person,

00:18:16.500 | this ability to shift the clock

00:18:19.780 | with light temperature, exercise, and food

00:18:22.240 | is vitally important for getting onto the new local schedule.

00:18:26.980 | And there's so much out there about jet lag.

00:18:28.600 | Today, I'm going to dial it down

00:18:29.880 | to one very specific parameter

00:18:31.960 | that all of you can figure out

00:18:34.260 | without any technology or devices

00:18:37.000 | and can apply for when you travel for work

00:18:40.780 | or pleasure or anytime you're jet lagged.

00:18:43.840 | And I want to absolutely emphasize

00:18:46.420 | that you don't have to travel to get jet lagged.

00:18:48.820 | Many of you are jet lagged.

00:18:50.760 | You're jet lagged because you're looking at your phone

00:18:52.360 | in the middle of the night.

00:18:53.320 | You're jet lagged

00:18:54.160 | because you're waking up at different times a day.

00:18:55.340 | You're jet lagged because your exercise

00:18:57.840 | is on a chaotic regime.

00:19:01.100 | Some days at this time, some days at that time.

00:19:03.640 | And if that works for you, great.

00:19:05.740 | I want to be really clear

00:19:06.900 | that a number of people always say,

00:19:08.420 | "Well, I know so-and-so that you only needed four hours

00:19:11.440 | of sleep or they're just fine.

00:19:14.200 | They traveled to Europe and it's just fine."

00:19:16.040 | There's a lot of individual variability.

00:19:17.600 | And we're going to talk about the origins

00:19:18.880 | of some of that variability.

00:19:20.260 | I mean, I know people that can eat anything

00:19:23.000 | and somehow seem to maintain great lipid profiles

00:19:25.980 | and body weight and fitness activities

00:19:31.680 | and I know some people that they eat one cracker

00:19:33.880 | and they sort of dissolve into a puddle of kind of tears

00:19:38.080 | because they think that that's going to throw them off

00:19:39.960 | and then maybe it does, I don't know.

00:19:41.800 | There's a tremendous amount of variability out there.

00:19:44.740 | So this is really about optimal and what's possible.

00:19:49.740 | And you have to ask,

00:19:51.400 | I can just say from personal experience,

00:19:53.120 | I suffer terribly from jet lag

00:19:56.140 | traveling in certain directions, but not others.

00:19:58.880 | Some people don't have trouble with jet lag.

00:20:00.720 | Many people will travel to a new location.

00:20:03.140 | They feel great for the first day and night

00:20:05.800 | and then they crash and they have trouble sleeping

00:20:08.100 | or they travel back and they have a terrible time

00:20:10.420 | getting back onto a normal schedule.

00:20:12.320 | And some of this varies with age

00:20:14.720 | and some of it varies with genetics.

00:20:16.880 | And there is no simple pill or anything that you can take

00:20:20.480 | to just get rid of jet lag.

00:20:22.420 | It doesn't work that way.

00:20:23.260 | If it worked that way, I would tell you.

00:20:26.080 | But there are some simple things that you can do.

00:20:28.580 | I'm going to arm you with the knowledge of what jet lag is

00:20:30.940 | and how it works.

00:20:32.420 | And contrary to what many people out there say and believe,

00:20:36.020 | I know that understanding mechanism

00:20:38.100 | affords you more flexibility.

00:20:39.940 | Why understand mechanism as just opposed to me

00:20:43.380 | just writing up a PDF and giving you a list of things to do?

00:20:45.740 | Well, what happens when you can't do those things

00:20:48.820 | in exactly the way they're written down?

00:20:50.260 | When you understand mechanism,

00:20:52.860 | you understand how to control the machine

00:20:55.900 | that is your biological system, your nervous system.

00:20:58.300 | So a little bit of understanding about mechanism

00:21:00.260 | goes a really long way.

00:21:02.840 | So that's where we're headed.

00:21:03.680 | Let's talk about what jet lag is.

00:21:05.880 | Okay, well, I promised that I wouldn't get too dark

00:21:08.420 | with all the terrible things that can happen with jet lag,

00:21:11.100 | but I'm about to get dark.

00:21:12.840 | There are quality peer-reviewed papers

00:21:17.060 | showing that jet lag will shorten your life.

00:21:19.860 | It will kill you earlier.

00:21:22.460 | I guess it means you'll die earlier.

00:21:25.400 | It doesn't actually kill you necessarily,

00:21:27.060 | although there are many cases

00:21:30.060 | where tourists end up stepping in front of buses,

00:21:32.500 | especially in countries where the cars and buses

00:21:35.040 | drive on the opposite side of the street

00:21:36.500 | that they're used to,

00:21:38.100 | who are jet lagged and lose their life that way.

00:21:39.980 | Jet lag is a serious thing.

00:21:41.680 | Sure, we had a family story about this.

00:21:43.580 | When I was growing up,

00:21:45.060 | I had a family member travel overseas for work

00:21:47.580 | and take a sleeping pill.

00:21:49.260 | I won't name the sleeping pill,

00:21:50.980 | though at the end I'm going to talk about sleeping pills,

00:21:53.180 | and had a case of total amnesia for a week.

00:21:57.120 | That's not entirely uncommon.

00:21:59.420 | If you've ever been really jet lagged and fallen asleep,

00:22:01.960 | doesn't even have to be in the middle of the day,

00:22:03.780 | woken up, you might not know where you are.

00:22:06.480 | And that's because time and space are really linked

00:22:08.480 | and the brain wasn't designed to be transported

00:22:10.860 | four, five, six hours into a new time zone.

00:22:13.520 | It just wasn't.

00:22:15.160 | Our brain and the biological mechanisms

00:22:17.480 | that govern circadian timing

00:22:19.560 | were designed to be shifted by a couple hours,

00:22:22.040 | not necessarily six or nine or 12 hours.

00:22:25.240 | So you really mess yourself up.

00:22:26.800 | I've had that experience.

00:22:27.720 | I usually experience it as fluctuations in mood.

00:22:30.440 | I flew 12 hours out of phase to Abu Dhabi once

00:22:33.920 | to give a talk at NYU Abu Dhabi, and it was a mess.

00:22:37.920 | I actually was getting vertigo.

00:22:40.820 | I wasn't hallucinating, but I was really out of it.

00:22:44.680 | And my mood was just all over the place.

00:22:47.320 | It was very bizarre.

00:22:49.060 | Jet lag, even if you don't experience it

00:22:51.640 | as mood shifts or amnesia, it can shorten your life.

00:22:56.080 | Now here's what's interesting.

00:22:58.160 | Traveling westward on the globe is always easier

00:23:03.160 | than traveling eastward, okay?

00:23:08.420 | It's interesting because the effects of jet lag on longevity

00:23:13.420 | have shown that traveling east

00:23:17.040 | takes more years off your life than traveling west.

00:23:21.740 | Now, of course, traveling 30 minutes

00:23:24.540 | into a new time zone or three hours,

00:23:26.540 | just one time zone over, or two time zones over, rather,

00:23:30.360 | is far less detrimental to your biology and psychology

00:23:34.220 | than a eight-hour shift or a nine-hour shift.

00:23:37.580 | Now, here's what's interesting.

00:23:39.280 | When we think about the effects of jet lag on longevity

00:23:44.020 | or this idea that it can shorten our lives,

00:23:49.080 | we have to ask ourselves, why?

00:23:51.020 | Why is that?

00:23:52.060 | And it turns out there's a pretty simple explanation

00:23:54.340 | for this.

00:23:55.780 | We've talked before about the autonomic nervous system,

00:23:57.980 | this set of neurons in our spinal cord and body and brain

00:24:01.200 | that regulate our wakefulness and our sleepiness.

00:24:03.700 | Turns out that human beings, and probably most species,

00:24:08.420 | are better able to activate and stay alert

00:24:12.080 | than they are to shut down their nervous system

00:24:15.080 | and go to sleep on demand.

00:24:16.460 | So if you really have to push

00:24:18.580 | and you really have to stay awake, you can do it.

00:24:20.300 | You can stay up later.

00:24:22.020 | But falling asleep earlier is harder.

00:24:24.720 | And that's why traveling East

00:24:26.300 | has a number of different features associated with it

00:24:29.520 | that because you're traveling East,

00:24:31.640 | you're trying to go to bed earlier.

00:24:34.420 | As a Californian, if I go to New York City,

00:24:37.320 | I've got to get to bed three hours early

00:24:38.900 | and wake up three hours early,

00:24:40.100 | much harder than coming back to California

00:24:42.540 | and just staying up a few more hours.

00:24:44.500 | And this probably has roots in evolutionary adaptation

00:24:49.500 | under conditions where we need to suddenly gather up and go

00:24:52.820 | or forage for food or fight

00:24:55.220 | or do any number of different things

00:24:57.600 | that we can push ourselves through the release of adrenaline

00:24:59.920 | and epinephrine to stay awake,

00:25:01.440 | whereas being able to slow down

00:25:03.260 | and deliberately fall asleep

00:25:04.660 | is actually much harder to do.

00:25:06.640 | So there's an asymmetry to our autonomic nervous system

00:25:08.860 | that plays out in the asymmetry of jet lag.

00:25:13.360 | So if you want to read up on this,

00:25:15.360 | because people have asked me about papers,

00:25:17.520 | you can look, there's a paper published

00:25:19.400 | by Davidson and colleagues, 2006, in Current Biology

00:25:22.360 | that talks about the differences in lifespan

00:25:25.820 | for frequent Eastward versus Westward versus no travel

00:25:30.820 | and longevity and et cetera,

00:25:34.080 | a number of different biological markers of longevity.

00:25:37.460 | So going East is harder

00:25:38.840 | because going to sleep earlier is harder

00:25:41.700 | if you're trying to do that on demand.

00:25:44.160 | Many people have turned to melatonin

00:25:45.780 | as a way to try and induce sleepiness.

00:25:48.120 | I'm going to talk about melatonin at the end.

00:25:50.140 | I've mentioned on previous podcasts,

00:25:51.980 | a number of you have asked for the evidence

00:25:54.000 | that melatonin is potentially detrimental

00:25:57.920 | to some hormone systems.

00:25:59.500 | Melatonin is a hormone, and I'll discuss that at the end,

00:26:02.520 | in particular, the role of melatonin

00:26:04.100 | in suppressing a hormone pathway

00:26:06.200 | that involves luteinizing hormone,

00:26:08.080 | testosterone in men and estrogen in females,

00:26:11.640 | as well as a really interesting peptide

00:26:13.140 | called kisspeptin, that's a cool name.

00:26:15.680 | All right, well, let's think about travel and what happens.

00:26:19.040 | Let's say you're not going Eastward or Westward,

00:26:22.600 | but you're going North or South.

00:26:24.680 | So if you go from, for instance,

00:26:26.200 | Washington, DC to Santiago, Chile,

00:26:28.680 | or you go from Tel Aviv, Israel to Cape Town, South Africa,

00:26:34.640 | you're just going North and South, right?

00:26:38.000 | And not, you know, either direction.

00:26:40.360 | You're not really moving into a different time zone.

00:26:42.800 | You're not shifting.

00:26:43.780 | So you will experience travel fatigue.

00:26:47.000 | And it turns out that jet lag has two elements,

00:26:48.920 | travel fatigue and time zone jet lag.

00:26:52.960 | Time zone jet lag is simply the inability

00:26:57.640 | of local sunlight and local darkness

00:27:01.160 | to match to your internal rhythm,

00:27:03.620 | this endogenous rhythm that you have.

00:27:05.480 | So before we get too complicated

00:27:09.300 | and too down in the weeds about this,

00:27:11.780 | I want to just throw out a couple of important things.

00:27:14.080 | First of all, I mentioned this earlier,

00:27:15.780 | but some people suffer from jet lag a lot.

00:27:17.960 | Other people, not so much.

00:27:20.000 | Most people experience worse jet lag as they get older.

00:27:24.240 | There are reasons for that because early in life,

00:27:26.880 | patterns of melatonin release are very stable and flat

00:27:31.360 | and very high actually in children.

00:27:33.400 | It's one of the reasons why they don't undergo puberty.

00:27:35.960 | Then it becomes cyclic during puberty,

00:27:37.640 | meaning it comes on once every 24 hours

00:27:40.560 | and turns off once every 24 hours, it's cycles, cyclic.

00:27:44.200 | And then as we get older, the cycles get more disrupted

00:27:47.500 | and we become more vulnerable to even small changes

00:27:50.340 | in schedule, et cetera, meal times, right?

00:27:53.600 | So jet lag gets worse as we age.

00:27:57.440 | In addition, there are other things that happen with age

00:28:01.440 | that people start doing less exercise,

00:28:04.780 | their digestion can get worse, et cetera.

00:28:07.280 | So some of the effects of age might not be direct effects

00:28:10.520 | of getting older, but some of the things

00:28:12.560 | that are correlated with being older,

00:28:14.280 | like people who are willing to have a regular exercise

00:28:17.000 | regime can use that exercise regime

00:28:18.780 | to shift their circadian clock.

00:28:20.620 | And I have a good friend, his father's in his 80s.

00:28:24.360 | He's still pushing out 25, 30 pushups each morning.

00:28:29.360 | He's on the Peloton or whatever it is,

00:28:31.600 | doing a lot of cycling.

00:28:32.440 | So some 80 year olds are doing that, many are not.

00:28:35.080 | Not many 30 year olds are not.

00:28:37.240 | But if you have a regular exercise program,

00:28:40.320 | that's going to make it easier to shift your circadian clock

00:28:44.120 | for sake of jet lag.

00:28:45.900 | And it's actually a knob you can turn

00:28:47.780 | and you can leverage for shifting your clock.

00:28:51.220 | Before we go any further,

00:28:52.360 | I want to make changing your internal rhythm really easy,

00:28:57.360 | or at least as easy and as simple

00:29:00.120 | as one could possibly make it, I believe.

00:29:02.960 | What I want to talk about is perhaps one of the most

00:29:05.840 | important things to know about your body and brain,

00:29:08.520 | which is called your temperature minimum.

00:29:10.920 | Most of you know your approximate weight.

00:29:12.860 | Some of you even know your blood pressure.

00:29:15.140 | Some of you might even know your body mass index.

00:29:18.520 | Some of you might know other things about your biology

00:29:20.620 | that have fancy names,

00:29:22.360 | but everyone should know their temperature minimum.

00:29:24.920 | Your temperature minimum doesn't require a thermometer

00:29:28.960 | to measure, although you could measure it.

00:29:31.360 | Your temperature minimum is the point in every 24 hour cycle

00:29:35.900 | when your temperature is lowest.

00:29:37.500 | Now, how do you measure that without a thermometer?

00:29:41.960 | It tends to fall 90 minutes to two hours

00:29:44.340 | before your average waking time.

00:29:47.000 | So I want to repeat that.

00:29:47.840 | Your temperature minimum tends to fall 90 minutes

00:29:51.300 | to two hours before your average waking time.

00:29:54.020 | So let's say you're not traveling

00:29:56.320 | and your typical wake up time is 5.30 AM.

00:29:59.940 | Your temperature minimum is very likely 3.30 AM or 4.00 AM.

00:30:04.900 | If you want, if any of you want to,

00:30:07.720 | you can measure your temperature minimum.

00:30:09.260 | You can get a thermometer

00:30:10.160 | and you can measure your temperature every couple hours

00:30:11.900 | for 24 hours and you can find your temperature minimum.

00:30:14.720 | What you're going to find is that you have a low point,

00:30:16.960 | the temperature minimum,

00:30:18.240 | and then your temperature will start to rise.

00:30:19.880 | You'll wake up about two hours later.

00:30:22.660 | Then your temperature will continue to rise

00:30:24.500 | into the afternoon.

00:30:25.340 | It will peak, maybe a little trough, sometimes that happens.

00:30:28.760 | And then it'll start declining slowly

00:30:33.180 | as you approach nighttime.

00:30:34.440 | There are things that will disrupt that temperature pattern,

00:30:38.280 | saunas, cold baths, intense exercise, et cetera.

00:30:42.840 | Meals tend to have a thermogenic effect

00:30:44.760 | that increases temperature slightly, little blips,

00:30:47.000 | but the overall cycle,

00:30:48.260 | 24 hour cycle of temperature has this pattern.

00:30:52.040 | And last time I talked about the seminal work

00:30:54.240 | of Joe Takahashi and others who have shown

00:30:56.540 | that temperature actually is the signal

00:30:58.900 | by which this clock above the roof of your mouth

00:31:01.860 | in trains or collectively pushes all the cells

00:31:05.380 | and tissues of our body to be on the same schedule.

00:31:08.700 | Temperature is the effector.

00:31:10.540 | And once you hear that, there should be an immediate,

00:31:13.580 | oh, of course, because how else would you get

00:31:15.820 | all these different diverse cell types

00:31:19.220 | to follow one pattern, right?

00:31:20.980 | A pancreatic cell does something very different

00:31:23.200 | than a spleen cell or a neuron, right?

00:31:27.940 | They're all doing different things at different rates.

00:31:30.300 | So the temperature signal can go out

00:31:31.840 | and then each one of those can interpret

00:31:33.340 | the temperature signal as one unified

00:31:35.360 | and consistent theme of their environment.

00:31:38.800 | So temperatures vary from person to person.

00:31:42.360 | Some people are 98.6.

00:31:43.960 | Some people run a little colder, et cetera,

00:31:45.480 | but you have a low point and you have a high point.

00:31:47.760 | Know your temperature minimum.

00:31:49.120 | How are you going to figure out this temperature minimum?

00:31:51.740 | The temperature minimum can be determined

00:31:54.280 | by taking the last three to five wake-up times.

00:31:58.620 | So let's say you wake up 7 a.m., 8 a.m., 3 a.m., happens.

00:32:03.620 | Take those, add them together,

00:32:07.060 | average them by adding them up

00:32:09.820 | and dividing by the number of days.

00:32:11.020 | That'll give you the average.

00:32:13.000 | If you're one of these people that wakes up at 3 a.m.

00:32:14.980 | and then goes back to sleep and sleeps till 10,

00:32:16.900 | your wake-up time was 10 a.m.

00:32:19.180 | If you use an alarm clock, your wake-up time

00:32:21.780 | is still when you get up, okay?

00:32:24.180 | I know alarm clocks have been kind of demonized,

00:32:27.920 | but in my world, being late and missing appointments

00:32:30.680 | is also demonized, so I use an alarm clock.

00:32:33.720 | Many people will wake up at exactly the same time each day.

00:32:38.560 | There tends to be some variation for people.

00:32:40.080 | Some people, it's going to vary

00:32:41.560 | depending on life circumstances,

00:32:42.800 | but average that for three to seven days or so.

00:32:45.340 | Take that wake-up time.

00:32:47.420 | You can then get an average

00:32:49.340 | or sort of typical temperature minimum.

00:32:52.580 | Okay, so now you know how to get your temperature minimum.

00:32:55.620 | Your temperature minimum is your absolute reference point

00:33:00.620 | for shifting your circadian clock,

00:33:03.700 | whether or not it's for jet lag or shift work

00:33:05.380 | or some other purpose.

00:33:06.980 | Here's the deal.

00:33:07.960 | If you expose your eyes to bright light in the four hours,

00:33:15.820 | maybe five or six, but in the four hours

00:33:18.540 | after your temperature minimum,

00:33:20.260 | your circadian clock will shift

00:33:25.500 | so that you will tend to get up earlier

00:33:27.900 | and go to sleep earlier in the subsequent days, okay?

00:33:31.900 | It's what's called a phase advance,

00:33:33.980 | if you'd like to read up on this further.

00:33:35.900 | You advance your clock, okay?

00:33:39.000 | However, if you view bright light

00:33:42.620 | in the four to six hours before your temperature minimum,

00:33:45.940 | you will tend to phase delay your clock.

00:33:50.020 | You will tend to wake up later and go to sleep later, okay?

00:33:54.540 | I'm going to repeat this

00:33:55.360 | because there's so much confusion out there

00:33:56.860 | and people talk about circadian time and all this.

00:33:58.820 | Find your temperature minimum.

00:34:00.200 | I tend to wake up at about 6 a.m.,

00:34:02.860 | sometimes 6.30, sometimes seven.

00:34:04.620 | It depends a lot on what I was doing the night before

00:34:06.740 | as I'm guessing it does for you,

00:34:08.220 | but that means that my temperature minimum

00:34:11.180 | is probably somewhere right around 4.30 a.m.,

00:34:14.180 | which means that if I wake up at 4.30 a.m.

00:34:17.660 | and I were to view bright light at 4.35 a.m.,

00:34:21.980 | I'm going to advance my clock.

00:34:24.400 | I'm going to want to go to bed earlier the subsequent night

00:34:28.100 | and wake up earlier the subsequent morning.

00:34:30.300 | And as I shift my wake up time,

00:34:34.900 | my temperature minimum shifts too, right?

00:34:37.020 | Because each time we shift our wake up time,

00:34:39.220 | our temperature minimum shifts,

00:34:40.920 | assuming that wake up time shifts

00:34:42.680 | more than 30 minutes or an hour, okay?

00:34:45.880 | If I were to view bright light

00:34:48.880 | in the four to six hours before 4.30 a.m., guess what?

00:34:53.060 | The next night I'm going to want to stay up later

00:34:55.420 | and I'm going to want to wake up later the subsequent morning

00:34:58.420 | Your temperature minimum is a reference point,

00:35:01.800 | not a temperature reading.

00:35:03.940 | Again, if you want to measure your temperature minimum

00:35:06.520 | and figure out what it is,

00:35:07.580 | 98 point whatever or 96 point whatever, that's fine.

00:35:10.680 | You can do that, but that information won't help you.

00:35:13.240 | What you need to know is what time

00:35:14.940 | your body temperature is lowest

00:35:16.240 | and understand that in the four hours or so

00:35:18.880 | just after that time, viewing light will advance your clock

00:35:22.780 | to make you want to get up earlier.

00:35:24.540 | And the four hours before your temperature minimum,

00:35:29.060 | viewing light will make you want to stay up later.

00:35:33.460 | Now, some people might be saying,

00:35:34.580 | well, I wake up early and I want to stay up late

00:35:36.820 | and I'm sleepy all day and I'm a mess or I feel fine.

00:35:39.560 | Look, let's talk about feeling fine.

00:35:42.940 | It turns out the definition of insomnia

00:35:45.820 | is when you're experiencing excessive sleepiness

00:35:49.080 | during the day.

00:35:49.920 | Sleepiness and fatigue are different, okay?

00:35:52.700 | So in the world of sleep medicine,

00:35:54.420 | fatigue is a physical exhaustion.

00:35:57.060 | Sleepiness is falling asleep,

00:35:59.660 | like falling asleep at your desk

00:36:01.640 | or falling asleep during lectures

00:36:03.000 | or there seems to be something special about my lectures

00:36:05.460 | that makes people want to fall asleep.

00:36:06.580 | So if this cures your insomnia, fantastic.

00:36:09.460 | However, in all seriousness, sleepiness during the daytime,

00:36:14.460 | unless it's around your temperature peak

00:36:17.280 | and only lasts about 90 minutes or so,

00:36:19.840 | is a sign of insomnia.

00:36:22.100 | It's a sign of lack of sleep.

00:36:23.640 | I want to be very, very clear

00:36:28.360 | that if you know your temperature minimum,

00:36:31.600 | you can shift your clock using light.

00:36:34.120 | You can also shift your clock by engaging in exercise

00:36:38.360 | in the four hours after your temperature minimum

00:36:40.320 | to wake up earlier on subsequent nights

00:36:43.120 | or exercise before then to delay your clock, okay?

00:36:46.400 | So now you can start to see and understand

00:36:48.880 | the logic of this system.

00:36:51.360 | And we'll talk about why this works

00:36:53.040 | and the underlying biology,

00:36:54.240 | but understanding that temperature is the effector

00:36:58.160 | and understanding that you have this low point

00:37:00.760 | that reflects your most sleepy point, essentially,

00:37:03.580 | right before waking up.

00:37:05.400 | And then temperature rises,

00:37:07.520 | you can now start to shift that temperature

00:37:09.480 | according to your travel needs.

00:37:12.200 | Here's one way in which you might do that.

00:37:14.680 | Let's say I am going to travel to Europe,

00:37:16.800 | which is nine hours ahead, typically, from California.

00:37:20.940 | I would want to determine my temperature minimum,

00:37:24.480 | which for me is about 4.30 AM, maybe 5 AM.

00:37:27.600 | And I would want to start getting up at about 5.30 AM

00:37:32.600 | and getting some bright light exposure,

00:37:36.120 | presumably from artificial sources

00:37:37.600 | because the sunlight isn't going to be out at that time,

00:37:41.220 | maybe even exercising as well,

00:37:42.640 | maybe even eating a meal at that time

00:37:45.200 | if that's in your practice.

00:37:47.080 | You would want to start doing that

00:37:49.720 | two or three days before travel.

00:37:51.480 | Because once you land in, or I land in Europe,

00:37:58.000 | chances are just viewing the sunrise or sunset in Europe

00:38:02.640 | is not going to allow me to shift my circadian clock.

00:38:05.420 | Some people say get sunlight in your eyes when you land,

00:38:07.560 | but that's not going to work

00:38:09.760 | because one of two things is likely to happen.

00:38:13.040 | With a nine hour shift like that,

00:38:14.440 | either I'm going to view sunlight

00:38:16.360 | at a time that corresponds to the circadian dead zone,

00:38:19.080 | the time in which my circadian clock can't be shifted,

00:38:22.500 | or I'm going to end up viewing sunlight

00:38:24.920 | at a time that corresponds to the four to six hour window

00:38:28.660 | before my temperature minimum.

00:38:32.660 | So it's going to shift me in exactly the opposite direction

00:38:35.760 | that I want to go.

00:38:37.160 | So it can be very, very challenging

00:38:39.820 | for people to adjust to jet lag.

00:38:41.920 | So you need to ask, am I traveling east

00:38:44.240 | or am I traveling west?

00:38:45.120 | Am I trying to advance my clock or delay my clock?

00:38:47.960 | Remember, viewing light, exercise, and eating

00:38:51.780 | in the four to six hours before your temperature minimum

00:38:54.080 | will delay your clock.

00:38:55.120 | Eating, viewing sunlight, and exercising,

00:38:58.240 | you don't have to do all three,

00:38:59.280 | but some combination of those in the four to six hours

00:39:01.920 | after your temperature minimum will advance your clock.

00:39:05.060 | And this is a powerful mechanism

00:39:06.680 | by which you can shift your clock anywhere

00:39:08.660 | from one to three hours per day, which is remarkable.

00:39:13.140 | That means your temperature minimum is going to shift out

00:39:15.200 | as much as three hours,

00:39:17.420 | which can make it such that you can travel

00:39:19.860 | all the way to Europe.

00:39:21.800 | And as long as you've prepared for a day or so

00:39:24.920 | by doing what I described back home,

00:39:27.800 | and then doing it when you arrive,

00:39:30.160 | you can potentially accomplish the entire shift

00:39:32.400 | within anywhere from 24 to 36 hours.

00:39:35.320 | And this is really important to emphasize

00:39:40.080 | that once you arrive in your new location,

00:39:42.600 | and here I'm talking about traveling eastward,

00:39:44.040 | California to Europe.

00:39:44.920 | Once you arrive in your new location,

00:39:47.360 | you have to keep track of what your temperature minimum was

00:39:51.360 | back home and how it's being shifted during your trip.

00:39:54.460 | Now it's much easier to do than you think.

00:39:56.680 | One of the unfortunate consequences of the smartphone

00:40:01.160 | is that you can't do something goofy

00:40:04.400 | like wearing two watches,

00:40:05.400 | one watch that corresponds to the time back home

00:40:07.440 | and another one that corresponds to the local time.

00:40:10.080 | Typically it updates automatically based on wifi, et cetera.

00:40:15.080 | But if you can keep track of the time back home,

00:40:19.280 | then you can easily shift your clock going forward.

00:40:22.520 | I'm hoping this makes sense.

00:40:24.120 | I really want to emphasize that you don't have to be precise

00:40:27.400 | down to the minute.

00:40:28.600 | Some of you may be asking,

00:40:29.760 | well, what about, you've got this temperature minimum,

00:40:32.380 | and if I view light one minute before it,

00:40:34.440 | then I'm going to delay my clock,

00:40:35.620 | and one minute after it, I'm going to advance my clock.

00:40:37.600 | It doesn't quite work like that, okay?

00:40:40.200 | But it's very important to understand

00:40:42.760 | that light is the primary way

00:40:44.120 | in which we can shift our clock.

00:40:46.340 | And now you should also be able to understand things

00:40:49.400 | like the circadian dead zone from about 9.30, 10 a.m.,

00:40:53.880 | all the way until six hours before your temperature minimum,

00:40:58.780 | you're not going to shift your clock.

00:41:00.240 | Nothing that you do in that time

00:41:01.520 | in terms of light viewing behavior, feeding, et cetera,

00:41:04.720 | is going to shift your clock.

00:41:06.160 | And so a lot of people are landing in Europe,

00:41:08.280 | getting sunlight in their eyes,

00:41:10.240 | and throwing their clock out of whack

00:41:12.820 | or not shifting their clock at all.

00:41:15.120 | This brings me to the other thing that's highly recommended,

00:41:18.360 | and I've mentioned this before,

00:41:19.400 | but you want to eat on the local meal schedule.

00:41:21.780 | If it's in your practice to fast, fast, that's fine.

00:41:26.220 | But when you eat,

00:41:27.500 | you want to eat within the local schedule for alertness.

00:41:31.540 | Okay.

00:41:32.380 | That means if you arrive and everyone's eating breakfast

00:41:35.920 | and you can't stomach the idea of breakfast

00:41:38.260 | in your new location 'cause your appetite isn't there,

00:41:40.100 | that means the clock in your liver,

00:41:41.620 | you have a clock in your liver, biological clock,

00:41:44.460 | has not caught up to the new time zone.

00:41:46.700 | You can force yourself to eat if you like,

00:41:51.220 | or you can skip that meal.

00:41:53.200 | But what you don't want to do

00:41:54.740 | is stay on your home meal schedule,

00:41:57.460 | waking up in the middle of the night and eating.

00:41:58.860 | That is really going to throw things off

00:42:00.380 | because a lot of the clocks in the periphery,

00:42:02.600 | like from the liver, the peripheral body,

00:42:04.660 | will send information back to the brain,

00:42:06.660 | and then the brain is getting really conflicted signals.

00:42:09.380 | So the temperature minimum is really your anchor point

00:42:12.260 | for shifting your clock best.

00:42:14.180 | I don't know why this information

00:42:15.260 | really hasn't made it into the popular sphere quite so much.

00:42:19.140 | There's all sorts of stuff about taking things like melatonin

00:42:22.560 | using binaural beats, a lot of kind of like

00:42:24.920 | more sophisticated, complicated,

00:42:28.220 | and potentially problematic ways

00:42:31.180 | of trying to shift the clock.

00:42:32.620 | Let's talk about melatonin,

00:42:34.340 | but first I just want to pause

00:42:35.900 | and shift gears a little bit

00:42:38.920 | because I talked about traveling eastward,

00:42:41.580 | but we haven't talked about traveling westward.

00:42:43.960 | So I want to do that now.

00:42:45.380 | Let's say you're traveling from New York to California

00:42:47.660 | or from Europe to California.

00:42:49.780 | The challenge there tends to be

00:42:52.220 | how can you stay up late enough?

00:42:54.220 | Now, some people are able to do this

00:42:56.260 | because as I mentioned earlier,

00:42:57.680 | the autonomic nervous system is asymmetrically wired

00:43:00.800 | such that it's easier to stay up late

00:43:03.020 | later than we would naturally want to

00:43:05.180 | than it is to go to sleep earlier.

00:43:06.700 | So let's say you land and it's 4 p.m.

00:43:09.820 | and you're just dying.

00:43:11.400 | You're in California, you came from Europe, it's 4 p.m.,

00:43:13.620 | and you really, really want to go to sleep.

00:43:16.520 | That's where the use of things like caffeine, exercise,

00:43:19.940 | and sunlight can shift you, right?

00:43:22.420 | If it's after your temperature peak,

00:43:24.740 | then viewing sunlight around 6 p.m. or 8 p.m.

00:43:27.660 | or artificial light, if there's in sunlight,

00:43:31.160 | will help shift you later, right?

00:43:33.500 | It's going to delay your clock

00:43:35.120 | and you're going to be able to stay up later.

00:43:37.280 | The worst thing you can do is take a nap

00:43:40.140 | that was intended to last 20 minutes or an hour,

00:43:43.120 | I do this routinely, and then wake up four hours later,

00:43:46.100 | or you wake up and it's midnight

00:43:48.280 | and you can't fall back asleep.

00:43:49.460 | You really want to avoid doing that.

00:43:52.040 | So provided it's not excessive amounts,

00:43:55.100 | stimulants like caffeine and coffee or tea

00:43:57.700 | can really help you push past that afternoon barrier

00:44:00.920 | and get you to sleep more like on the local schedule

00:44:05.020 | and eating on the local schedule as well.

00:44:07.920 | A number of people have asked about the use of melatonin

00:44:12.180 | to induce sleepiness.

00:44:13.900 | All right, well, let's think about what melatonin is.

00:44:16.740 | Melatonin is this hormone

00:44:17.980 | that's released from the pineal gland, which is this gland.

00:44:21.300 | A couple of notes about the pineal,

00:44:23.060 | 'cause I've been getting a lot of questions about this.

00:44:25.100 | I'm probably going to draw some fire for this,

00:44:26.640 | but I'd be happy to have a thoughtful, considerate debate

00:44:31.640 | with some peer-reviewed papers in front of us.

00:44:34.780 | The pineal does make this hallucinogenic molecule

00:44:37.860 | they call DMT, but in such minuscule amounts

00:44:41.140 | that it is not responsible for the hallucinations you see

00:44:44.120 | in sleep and dreaming.

00:44:45.220 | Sorry, folks.

00:44:46.100 | It's also not responsible for the hallucinations

00:44:48.000 | you might see through other approaches to DMT.

00:44:51.100 | It's just not, that's not where the DMT comes from.

00:44:53.680 | It's infinitesimally small amounts.

00:44:56.440 | There are a lot of kind of wacky claims out there

00:44:59.940 | about calcification of the pineal and fluoride

00:45:03.380 | and this kind of thing.

00:45:04.500 | Look, the pineal sits in an area of the brain

00:45:10.680 | near the fourth ventricle,

00:45:12.260 | where the skull is not terribly far away,

00:45:16.280 | although there's some overlapping neural tissue.

00:45:18.620 | And with age, there's some aggregation

00:45:22.180 | of some of the meninges and other things around there

00:45:24.980 | that stick to the skull.

00:45:26.300 | Young brains don't look like old brains,

00:45:27.860 | but there's no calcification of the pineal, all right?

00:45:30.900 | So you can forget about calcification

00:45:33.060 | of the pineal is a problem.

00:45:35.180 | I don't know where that whole thing got started,

00:45:36.940 | but that's not an issue.

00:45:39.000 | Your pineal will churn out melatonin in my whole life.

00:45:43.220 | Melatonin induces sleepiness.

00:45:45.660 | Melatonin during development is also responsible

00:45:49.620 | for timing the secretion of certain hormones

00:45:52.300 | that are vitally important for puberty.

00:45:55.220 | Does melatonin control the onset of puberty?

00:45:58.900 | Not directly, but indirectly.

00:46:01.500 | Melatonin inhibits something called

00:46:03.660 | gonadotropin-releasing hormone,

00:46:05.180 | which is a hormone that's released from your hypothalamus,

00:46:07.340 | also roughly above the roof of your mouth and your brain.

00:46:10.100 | Gonadotropin-releasing hormone is really interesting

00:46:11.960 | 'cause it stimulates the release of another hormone

00:46:14.320 | called luteinizing hormone,

00:46:15.800 | which in females causes estrogen

00:46:19.540 | to be released within the ovaries.

00:46:22.520 | It's involved in reproductive cycles.

00:46:24.260 | And in males, stimulates testosterone

00:46:27.340 | from the sertoli cells of the testes.

00:46:30.400 | Melatonin is inhibitory to GnRH,

00:46:34.620 | gonadotropin-releasing hormone,

00:46:35.900 | and therefore is inhibitory to LH, luteinizing hormone,

00:46:38.620 | and therefore is inhibitory to testosterone and estrogen.

00:46:41.560 | There's just no two ways about it.

00:46:43.260 | There is immense amount of data on the fact

00:46:50.140 | that high levels of melatonin in seasonally breeding animals

00:46:54.360 | takes the ovaries from nice and robust ovaries

00:46:56.980 | that are capable of deploying eggs and this kind of thing,

00:47:00.140 | and literally shrinking them

00:47:02.060 | and making these animals infertile.

00:47:04.360 | These are very high levels of melatonin

00:47:05.780 | in seasonal breeders in winter.

00:47:07.380 | Melatonin in males of seasonal breeders

00:47:11.520 | takes the testes and shrinks them.

00:47:13.900 | Long ago when I was at UC Berkeley as a master student,

00:47:17.700 | I was working on neuroendocrinology

00:47:19.860 | and we were working on this hamster species

00:47:22.560 | of seasonal breeders.

00:47:23.500 | And basically when days are long, which inhibits melatonin,

00:47:27.480 | these little Siberian hamsters, as they're called,

00:47:30.740 | have testes about the size of sort of typical table grapes,

00:47:34.740 | although that's a weird way to put it.

00:47:36.640 | When days get shorter and the melatonin signal gets longer

00:47:41.000 | because light inhibits melatonin,

00:47:42.360 | days get shorter, melatonin gets longer,

00:47:43.920 | those same hamsters would have testes

00:47:46.680 | that would involute to the size of about a grain of rice.

00:47:49.440 | Now, this does not happen in humans in short days,

00:47:53.780 | but nonetheless, the melatonin signal

00:47:56.240 | really does have a ton of effects on the hormone system.

00:47:59.100 | Now, does that mean that if you've been taking melatonin,

00:48:02.120 | you've really screwed up your hormones?

00:48:03.220 | Not necessarily.

00:48:04.060 | Does it mean if a kid has been taking melatonin

00:48:05.780 | that's really screwing up their puberty?

00:48:07.340 | Not necessarily, and here's why.

00:48:09.100 | Melatonin operates on a concentration level.

00:48:15.580 | So in a child that's very, very small,

00:48:18.640 | that has high levels of melatonin,

00:48:21.220 | it actually can inhibit GnRH, LH, testosterone, or estrogen,

00:48:25.360 | depending on the sex of the child.

00:48:27.960 | But as that child grows through other mechanisms,

00:48:30.300 | like growth hormone release, et cetera,

00:48:32.060 | that same amount of melatonin released from the pineal

00:48:34.400 | is now diluted over a much larger body,

00:48:36.680 | so the concentration actually goes way, way down, okay?

00:48:40.820 | But here's the problem with supplementing melatonin.

00:48:43.200 | As I mentioned in the previous episode,

00:48:45.220 | concentrations of melatonin in many commercial supplements

00:48:48.280 | have been shown to be anywhere from 85% to 400%

00:48:52.420 | of what's listed on the bottle.

00:48:54.460 | So when you take melatonin, or a child takes melatonin,

00:48:57.300 | oftentimes they are taking

00:48:58.400 | supra-physiological levels of melatonin,

00:49:01.820 | which, at least by my read and the literature,

00:49:06.500 | says that it could have dramatic effects

00:49:08.760 | on timing and course of things like puberty.

00:49:12.620 | So it's not so much that the journals have come out saying,

00:49:16.160 | oh, taking that melatonin inhibits puberty,

00:49:19.500 | it's that no single study has been done

00:49:21.280 | with the supra-physiological levels of melatonin

00:49:23.780 | that are present in a lot of these supplements

00:49:26.120 | in developing children.

00:49:29.040 | So melatonin is used widely for inducing sleepiness

00:49:33.720 | when you want to fall asleep

00:49:34.880 | in the new location that you've arrived, right?

00:49:37.260 | You can't fall asleep,

00:49:38.100 | you take melatonin, it helps you fall asleep.

00:49:40.480 | It does not help you stay asleep.

00:49:42.920 | In addition to that, melatonin has been kind of touted

00:49:46.780 | as the best way to shift your circadian clock.

00:49:49.480 | I'm happy to go on record saying,

00:49:51.240 | look, if you need melatonin,

00:49:52.400 | you can work with a doctor or somebody

00:49:53.760 | who really understands circadian and sleep biology,

00:49:56.000 | go for it if that's your thing.

00:49:57.920 | But I, as always on this podcast and elsewhere,

00:50:01.720 | I have a bias toward behavioral things

00:50:05.680 | that you can titrate and control,

00:50:06.960 | like exposure to light, exercise, temperature, et cetera,

00:50:09.880 | that have much bigger margins for safety

00:50:12.680 | and certainly don't have these other endocrine effects

00:50:14.680 | that we've been thinking about and talking about.

00:50:17.380 | So if you want to take melatonin in the afternoon

00:50:20.680 | in order to fall asleep or in the evening,

00:50:22.800 | be my guest, that's up to you.

00:50:24.840 | Again, you're responsible for your health, not me.

00:50:27.720 | But for many people,

00:50:29.640 | melatonin is not going to be the best solution.

00:50:32.280 | The best solution is going to be to use light

00:50:35.140 | and temperature and exercise

00:50:36.920 | on either side of the temperature minimum

00:50:39.180 | to shift your clock both before your trip

00:50:41.040 | and when you land in your new location

00:50:42.760 | and your clock starts to shift.

00:50:44.640 | Okay, so now you know my opinions about melatonin.

00:50:47.920 | Feel free to filter them through your own opinions

00:50:50.960 | and experiences with melatonin.

00:50:53.320 | And now you also understand what your temperature minimum is

00:50:56.880 | and how it represents an important landmark,

00:50:59.560 | either side of which you can use light temperature

00:51:02.960 | and exercise to shift your clock.

00:51:05.480 | Just to remind you a little bit about temperature,

00:51:07.120 | if you want to shift your clock,

00:51:09.840 | typically you would do that by,

00:51:12.040 | you could take a hot shower

00:51:13.120 | and then that will have a cooling effect

00:51:15.200 | after the hot shower.

00:51:16.560 | And if you were to get into a cold shower or an ice bath,

00:51:20.860 | if you have access to one,

00:51:22.220 | afterward there's going to be a thermogenic effect

00:51:24.520 | of your body increasing temperature.

00:51:26.720 | And if you just think about your natural rhythm back home

00:51:30.060 | when everything's stable,

00:51:31.300 | you have a nadir, a low point in,

00:51:35.500 | which is your temperature minimum,

00:51:36.620 | and then you have a peak and you think about

00:51:38.840 | when you're doing this hot or cold shower in that rhythm,

00:51:42.580 | now you should be able to understand

00:51:44.000 | how you're shifting your rhythm.

00:51:45.720 | That temperature rhythm is the one that's going to move.

00:51:48.040 | Give you an example.

00:51:49.440 | If I were to wake up in the morning

00:51:51.740 | and let's say I wake up at 6 a.m.,

00:51:54.440 | my temperature I know is rising,

00:51:55.960 | I've passed my temperature minimum,

00:51:57.620 | if I were to get into a hot shower

00:52:00.160 | that would then lower my body temperature when I got out,

00:52:04.420 | that is not normally what's happening

00:52:06.400 | first thing in the morning.

00:52:08.220 | And therefore my clock would very likely get phase delayed.

00:52:12.260 | Right, it's going to delay the increase in temperature.

00:52:15.140 | Whereas if I got into a cold shower,

00:52:17.360 | something I don't personally like to do,

00:52:18.640 | but I've done from time to time,

00:52:20.800 | or an ice bath, that's going to then

00:52:22.440 | have a rebound increase in body temperature

00:52:24.880 | and is going to phase advance my clock.

00:52:26.700 | That peak in the afternoon is going to come

00:52:28.880 | about an hour earlier.

00:52:30.380 | I'm going to want to go to bed earlier, later that night.

00:52:33.000 | So you can start to play these games

00:52:34.300 | with timing and hot and cold,

00:52:36.400 | with meals, whether or not you eat or you don't eat,

00:52:38.920 | and with light exposure,

00:52:40.140 | whether or not you view light or you don't view light.

00:52:42.620 | So now you can start to see why understanding

00:52:44.600 | the core mechanics of a system

00:52:46.660 | can really give you the most flexibility

00:52:48.420 | because I could spend the next 25 years of my life

00:52:53.200 | answering every question

00:52:54.420 | about every nuanced pattern of travel.

00:52:56.740 | Well, we're going to Sydney and then we're going there.

00:52:58.700 | What should I do?

00:52:59.620 | But that's on you.

00:53:00.760 | You need to figure out your temperature minimum

00:53:02.920 | and your temperature peak, if you like,

00:53:04.700 | and then use these parameters to, it gives you flexibility.

00:53:07.420 | And that really underscores the most important thing

00:53:09.460 | is that when you understand mechanism,

00:53:10.920 | it's not about being neurotically attached

00:53:13.620 | to a specific protocol.

00:53:14.660 | It's the opposite.

00:53:15.780 | It gives you power to not be neurotically attached

00:53:18.600 | to a specific protocol.

00:53:19.980 | It can give you great confidence and flexibility

00:53:22.660 | in being able to shift your body rhythms however you want.

00:53:24.740 | And when things get out of whack,

00:53:25.700 | you can tuck them right back into place.

00:53:27.700 | One thing that's common

00:53:30.660 | is that people need to do a quick trip.

00:53:32.660 | It's not always that you're going to go to, you know,

00:53:34.660 | on vacation for two weeks or, you know,

00:53:36.980 | work someplace else for weeks on end.

00:53:40.080 | If your trip is 48 hours or less,

00:53:44.660 | stay on your home schedule.

00:53:46.560 | This can be tough and it may require scheduling meetings

00:53:50.100 | according to your home schedule.

00:53:52.220 | But if you can somehow manage that,

00:53:55.420 | the best thing to do would be to stay on your home schedule.

00:53:58.020 | Your clock is not going to shift more than a couple hours,

00:54:01.460 | even if you do everything correctly in one day, okay?

00:54:06.060 | So if I were to travel, say to Europe,

00:54:09.200 | I've actually done this.

00:54:10.060 | I did a 24 hour trip to Basel, Switzerland,

00:54:12.280 | gave a talk and came back.

00:54:13.460 | People thought I was crazy,

00:54:14.420 | but I had a little bit of travel fatigue.

00:54:16.840 | 'Cause remember there's fatigue

00:54:17.820 | from the actual travel experience.

00:54:19.800 | The novelty of it, the air is never great on the planes.

00:54:23.680 | This was even true before.

00:54:24.780 | There were mask requirements and things like that.

00:54:27.100 | There's the travel fatigue,

00:54:28.220 | but you don't throw your clock off.

00:54:30.680 | If you stay 48 hours,

00:54:33.140 | then you start to shift a little bit.

00:54:36.420 | 72, that's when you start running into trouble.

00:54:38.840 | The transit time is also important,

00:54:41.160 | but I would say if it's three days or less,

00:54:43.600 | stay on your home schedule as much as you can.

00:54:46.800 | And because sunlight isn't under your control,

00:54:49.920 | unless there's something about you I don't know,

00:54:51.960 | that's when traveling with some sort of bright light,

00:54:54.580 | like the light pad that I have down there

00:54:56.960 | that I showed earlier.

00:54:58.720 | For those of you listening just on audio,

00:55:00.080 | it's just, it looks like an eight and a half by 11 pad.

00:55:03.320 | It's actually not designed for wake up.

00:55:04.840 | It's actually designed, it's a drawing pad,

00:55:06.720 | and you can, and it emits about a thousand lux of light.

00:55:11.720 | And so if you want to travel with something like that,

00:55:15.080 | you can use that in your hotel room

00:55:16.800 | to wake up when you like.

00:55:19.260 | Some people will use nightshades,

00:55:22.200 | you know, not the nightshades that you eat

00:55:24.640 | or that some people say you're not supposed to eat.

00:55:25.980 | I don't know anything about that.

00:55:27.060 | But the eye covers that to keep light out,

00:55:31.780 | those can be very useful on planes and in hotels and so on.

00:55:36.480 | So you can use light and dark

00:55:38.600 | and you can travel with your light and dark devices

00:55:42.320 | so that you can stay on your home schedule

00:55:44.240 | and get most of your light

00:55:45.260 | when it would be your normal wake up time back home.

00:55:48.680 | And what's kind of nice is if you know

00:55:50.880 | when your circadian dead zone is back home,

00:55:53.360 | which is generally for most people around 10 a.m.

00:55:57.720 | to about 3 p.m.,

00:55:59.640 | so basically the rising phase of your temperature,

00:56:02.920 | then you can also feel free to be outside

00:56:06.640 | without having to wear sunglasses

00:56:07.960 | or you don't have to worry about light exposure.

00:56:09.880 | But if you know that window before your temperature minimum,

00:56:14.480 | that four to six hour window,

00:56:15.900 | that's the time when if you're viewing a lot of light

00:56:17.960 | in your new location,

00:56:19.480 | you are going to shift your clock pretty considerably

00:56:21.960 | and then you can come back home and have a terrible time.

00:56:24.680 | At the end of graduate school, I went to Australia,

00:56:27.200 | the remarkable country, incredible people,

00:56:29.520 | incredible wildlife, an amazing time.

00:56:31.680 | I came back and it was the first time in my life

00:56:34.200 | where I couldn't sleep on a regular schedule.

00:56:36.500 | I was sleeping in like hour long increments

00:56:38.660 | throughout the day.

00:56:39.500 | It was a nightmare.

00:56:40.860 | And it took me weeks to get back on target.

00:56:44.440 | And the way I was able to do that was exercising consistently

00:56:47.920 | at the same time every 24 hours,

00:56:50.580 | turning my home into essentially a cave at night,

00:56:54.760 | even covering up the windows,

00:56:56.400 | and then getting as much bright light in my eyes

00:56:58.480 | as I possibly could during the day, no sunglasses, et cetera.

00:57:01.940 | So it can take some real work

00:57:03.200 | if your clock gets thrown out of whack.

00:57:05.520 | There's a phenomenon called ICU psychosis,

00:57:08.580 | where people that are in the intensive care unit

00:57:11.080 | in hospitals actually lose their mind.

00:57:13.440 | They become psychotic, hallucinations, et cetera.

00:57:18.000 | And it's because of altered circadian cycles.

00:57:21.240 | We know this because they're exposed to these lights

00:57:23.960 | and these sounds, people coming in and checking on them.

00:57:26.000 | They leave the hospital or in some cases,

00:57:28.200 | there've been experiments where people are placed

00:57:29.500 | near a window where they get some natural light

00:57:31.320 | and these psychotic symptoms disappear,

00:57:33.760 | presuming there weren't psychotic symptoms beforehand,

00:57:37.200 | before they entered the hospital.

00:57:38.760 | So it's pretty dramatic what light can do

00:57:42.720 | to the psyche and to the body.

00:57:44.840 | So let's talk a little bit about a different form of jet lag

00:57:49.160 | that requires no planes, no trains, no automobiles,

00:57:52.920 | and that's shift work.

00:57:55.400 | Shift work is becoming increasingly common.

00:57:58.180 | Many of us are shift working even though we don't have to.

00:58:02.040 | We're doing work in the middle of the night.

00:58:03.920 | We are working on our computers at odd hours,

00:58:08.200 | sleeping during the day.

00:58:09.200 | A lot of people who are under shelter in place type stuff

00:58:12.560 | are doing more of this.

00:58:15.120 | Kids with the drifting school schedules.

00:58:18.040 | Here's the deal with shift work.

00:58:19.760 | If there's one rule of thumb for shift work,

00:58:22.660 | it's that if at all possible,

00:58:25.860 | you want to stay on the same schedule for at least 14 days,

00:58:29.820 | including weekends.

00:58:31.660 | Now that should immediately cue the non-shift workers

00:58:34.900 | to the importance of not getting too far off track

00:58:37.620 | on the weekend even if you're not a shift worker.

00:58:39.340 | So sleeping in on Sunday is not a good idea.

00:58:43.000 | The most important thing about shift work

00:58:46.420 | is to stay consistent with your schedule.

00:58:49.140 | Now I had a conversation on an Instagram Live

00:58:52.060 | with Samir Hattar, who's a neuroscientist

00:58:55.980 | at the National Institutes of Mental Health.

00:58:57.560 | He's actually the head of the Chronobiology Unit there.

00:58:59.660 | And he was really emphasizing this point

00:59:02.200 | because shift work where people are doing

00:59:04.160 | the so-called swing shift,

00:59:05.340 | where they're working four days on one shift

00:59:07.000 | and four days on another is extremely detrimental

00:59:10.260 | to a number of health parameters.

00:59:11.540 | It gets the cortisol release from the adrenals

00:59:14.880 | really out of whack.

00:59:16.240 | And there are these cortisol spikes

00:59:18.440 | at various hours of the day.

00:59:20.160 | It messes up learning.

00:59:21.540 | It really disrupts the dopamine system and wellbeing.

00:59:24.660 | It is a serious, serious problem.

00:59:26.540 | So if you can negotiate with your employer

00:59:29.620 | to stay on the same shift for two weeks at a time,

00:59:34.180 | that's going to be immensely beneficial

00:59:35.820 | and will help you offset a lot of the negative effects

00:59:37.920 | of shift work.

00:59:38.760 | Now, I don't presume that all of you

00:59:41.680 | are going to be able to do that.

00:59:43.240 | Some of you just don't have that level of control.

00:59:46.400 | And of course, I want to acknowledge

00:59:48.040 | that shift workers are essential, right?

00:59:51.520 | Of course, first responders, firefighters,

00:59:53.460 | police officers, paramedics, et cetera,

00:59:55.700 | but also pilots, nurses,

00:59:58.660 | people working on the hospital wards,

01:00:02.580 | people picking up trash.

01:00:04.140 | These night shifts are critical

01:00:06.100 | to our functioning as a society,

01:00:07.880 | as I'm sure all of you can appreciate.

01:00:09.860 | If you're going to work a shift where,

01:00:13.780 | let's say you start at 4 p.m. and you end at 2 a.m.,

01:00:17.780 | excuse me, then there's some important questions

01:00:21.220 | that arise.

01:00:22.060 | For instance, should you see light during your shift?

01:00:26.280 | Well, this is a matter of personal choice,

01:00:29.600 | but ideally you want to view as much light as possible

01:00:32.280 | and as safely possible when you need to be alert.

01:00:35.260 | So that would mean from 4 p.m. to 2 a.m.

01:00:38.120 | And then you would want to sleep.

01:00:40.180 | So using light as a correlate of alertness

01:00:45.900 | and using darkness as a correlate of sleepiness,

01:00:48.920 | what this means is see as much light as you safely can

01:00:51.480 | during the phase of your day when you want to be awake.

01:00:55.100 | So it's the same thing I said way back

01:00:56.320 | at the beginning of this podcast episode.

01:00:59.520 | And see as little light as safely possible

01:01:02.800 | and allows you to function during the time

01:01:04.960 | when you want to be asleep.

01:01:06.320 | So if you're finishing out that 2 a.m. shift,

01:01:08.880 | that's when you would want to avoid bright light exposure,

01:01:12.760 | you'd want to go home,

01:01:13.880 | you'd really want to avoid watching TV if possible.

01:01:16.600 | If you need that in order to fall asleep,

01:01:18.180 | that would be a case where something like dimming the screen

01:01:21.720 | plus blue blockers, if that's in your practice,

01:01:25.000 | or you want to do that would be helpful

01:01:27.800 | and then going to sleep.

01:01:28.700 | And then you'll probably wake up late in the afternoon

01:01:31.640 | or early afternoon.

01:01:33.040 | Some of you might say, wait, Huberman,

01:01:34.960 | I thought you don't like blue blockers.

01:01:36.100 | I never said I don't like blue blockers.

01:01:37.440 | I don't like people wearing blue blockers

01:01:38.840 | at the time of day when they want to be alert.

01:01:40.520 | And I don't like people asserting that blue blockers

01:01:43.200 | can prevent circadian shifts

01:01:45.040 | simply because people are wearing them.

01:01:46.380 | The brightness of light is what's important.

01:01:48.000 | It's not about the blue.

01:01:49.700 | So if you want to wear them, wear them,

01:01:53.500 | or just dim the lights or turn the lights off.

01:01:56.180 | So let's say you go to sleep at,

01:01:59.140 | you get home after this 4 p.m. to 2 a.m. shift,

01:02:02.600 | you maybe eat something, you go to sleep,

01:02:05.480 | and you wake up and it's noon or 1 p.m.

01:02:10.480 | Should you get light in your eyes?

01:02:12.240 | Well, your first assumption,

01:02:14.620 | based on what I've said previously,

01:02:15.860 | might be that you're in the circadian dead zone,

01:02:17.680 | that you can't because it's noon or 1 p.m.

01:02:20.260 | But you're not in the circadian dead zone

01:02:21.800 | because you're somebody who goes to sleep

01:02:23.800 | early in the morning at 2 a.m.

01:02:27.300 | So it's not like the circadian dead zone

01:02:29.740 | is a strict time of day.

01:02:31.580 | It's an internal biological clock.

01:02:34.020 | So what do you need to know?

01:02:36.080 | You guessed it.

01:02:36.980 | You need to know your temperature minimum.

01:02:39.180 | You need to know whether or not

01:02:40.880 | your temperature is increasing or decreasing.

01:02:43.740 | And now we can make this whole thing even simpler

01:02:45.820 | and just say if your temperature is decreasing, avoid light.

01:02:50.480 | If your temperature is increasing, get light.

01:02:54.520 | It's that simple.

01:02:56.920 | Okay, if your temperature is decreasing, avoid light.

01:03:01.120 | If your temperature is increasing, get light.

01:03:03.600 | The shift worker who works from 4 p.m. until 2 a.m.

01:03:09.600 | has a temperature rhythm that's very different than mine

01:03:12.880 | where I wake up around 6 a.m., 5 a.m.,

01:03:15.600 | and I go to sleep around 11 p.m., okay?

01:03:19.720 | We both have a 24-hour-ish circadian cycle

01:03:23.560 | except mine is more aligned to the rise

01:03:25.980 | and setting of the sun and theirs is not, right?

01:03:29.900 | So you have to know your internal temperature rhythm

01:03:33.360 | and know you don't have to walk around with a thermometer

01:03:37.220 | wherever taking your temperature.

01:03:39.360 | Although it'd be great if some of the devices

01:03:41.140 | that are out there, people are counting their steps.

01:03:43.420 | I think it'd be great if people had a circadian body

01:03:46.220 | temperature measurement.

01:03:47.060 | I'm not involved in any of this device development

01:03:48.900 | but I think it's a real call to arms, pun intended,

01:03:52.060 | to have a wristband that would measure temperature

01:03:55.060 | and would tell you your temperature minimum

01:03:56.500 | when you travel or whatnot.

01:03:57.580 | I don't know, maybe some of these devices already do that

01:04:00.240 | but if they don't, they should.

01:04:02.500 | It's absolutely absurd to me

01:04:03.600 | why we wouldn't have this simple measurement.

01:04:05.060 | Very easy to get that kind of information.

01:04:07.380 | You don't even need the exact temperature read.

01:04:10.480 | All you need to know is the high and low point.

01:04:13.100 | So let's say you're a shift worker

01:04:14.900 | who really is nocturnal, you're flipped.

01:04:18.240 | Well, you want to stay on that nocturnal schedule.

01:04:20.940 | Now that can be very hard on families and social life

01:04:24.220 | of all kinds but the person who is working say from,

01:04:27.380 | you know, 8 p.m., like sundown to sunrise,

01:04:31.980 | this raises a question.

01:04:34.380 | Should they be looking at the sunrise

01:04:37.180 | and should they be watching the sunset,

01:04:39.500 | waking up with the sunset, going to sleep with the sunrise?

01:04:43.060 | You think, well, is that light going to throw them off?

01:04:46.260 | Probably not.

01:04:47.160 | It's just actually going to invert

01:04:48.480 | what sunrise and sunset are.

01:04:50.200 | When they're waking up in the morning,

01:04:52.620 | if they look at the, you know,

01:04:54.380 | they get some sunlight in their eyes,

01:04:55.700 | they look at the sun and get some bright light from devices

01:04:58.520 | or overhead lights in their apartment or home,

01:05:01.060 | well, that's going to tend to wake them up

01:05:03.220 | if it's in the evening, right?

01:05:06.220 | So it's, you know, I don't know if I stated that clearly

01:05:08.760 | but if in the evening the sun is setting

01:05:10.360 | and they're looking at that setting sun,

01:05:11.820 | that is the morning sun for that person

01:05:15.420 | and it will wake them up for their night shift.

01:05:18.520 | So temperature rising.

01:05:20.260 | Then toward morning, what's happening?

01:05:22.600 | Okay, well, they're closing out their work shift,

01:05:24.380 | you're going home, the sun is rising.

01:05:26.980 | Do you look at the rising sun?

01:05:28.440 | Well, based on what you now know,

01:05:31.260 | your eyes are very sensitive

01:05:32.700 | to resetting of circadian clocks.

01:05:34.040 | What will it do at that time?

01:05:35.380 | If this were a classroom,

01:05:36.260 | I would either cold call on somebody

01:05:38.300 | or I'd wait for the oh, oh, oh, oh person in the audience.

01:05:41.660 | Inevitably exists.

01:05:42.880 | So temperature for that person,

01:05:46.740 | they've been up for a while,

01:05:48.060 | temperature is falling, not rising.

01:05:50.300 | For me, it would be rising,

01:05:52.380 | but 'cause I'm not diurnal, I'm awake during the day.

01:05:56.540 | For that person, the temperature is falling

01:05:58.260 | and so they view light while temperature is falling.

01:06:01.140 | What's it going to do?

01:06:01.980 | It's going to phase delay them.

01:06:04.020 | It's going to make it harder for them

01:06:05.400 | to get to sleep the following night.

01:06:07.240 | So you would say that person should watch the setting sun

01:06:10.500 | to help them wake up

01:06:12.140 | 'cause they're going to work the night shift,

01:06:13.580 | but should probably have sunglasses on

01:06:15.200 | or avoid viewing bright light before they go to sleep.

01:06:19.160 | So it's the same thing.

01:06:20.200 | They're just on an inverted,

01:06:21.300 | as a typical person who's diurnal,

01:06:24.220 | but they're on an inverted schedule.

01:06:26.460 | So I'm really trying hard here

01:06:28.860 | to make this all really clear.

01:06:31.140 | There are kind of two patterns of requests in the world

01:06:35.600 | I'm noticing as I've kind of ventured

01:06:37.240 | into this landscape of social media and podcasts.

01:06:40.840 | There are people who want to know every detail,

01:06:42.480 | want to quantify everything

01:06:43.600 | 'cause they want to get it exactly right.

01:06:45.000 | These are like the graduate students and students

01:06:47.680 | that don't want to make a mistake.

01:06:49.180 | And to quote my graduate advisor,

01:06:51.220 | provided the mistakes are not dangerous,

01:06:54.600 | certainly not lethal,

01:06:56.160 | you kind of want to make a few little mistakes

01:06:59.720 | so that you can adjust, right?

01:07:01.620 | You don't want to endanger yourself,

01:07:03.080 | but it's actually, you're not going to get things perfect.

01:07:05.960 | That's called learning.

01:07:06.780 | Learning is when you realize,

01:07:07.900 | ah, I viewed some this time and then I stayed up

01:07:10.020 | and it really messed me up.

01:07:11.160 | I'll never do that again.

01:07:12.420 | The other category of people seem to want

01:07:18.040 | the one size fits all kind of like,

01:07:20.160 | give me this pill or give me this protocol.

01:07:22.820 | And those things generally work,

01:07:25.000 | but they don't afford people flexibility.

01:07:27.560 | And if there's anything like that,

01:07:29.580 | it's this temperature minimum thing

01:07:31.820 | that I've been just hammering on again

01:07:33.720 | and again and again today,

01:07:34.700 | because it's something that you own

01:07:36.820 | and that you can really use as a key landmark

01:07:39.820 | for shifting your clock.

01:07:41.760 | I suppose there's a third category,

01:07:44.140 | which is people who accept that biological systems

01:07:48.040 | are actually much more forgiving

01:07:49.600 | than the way they're sometimes described.

01:07:51.960 | And I'm going to use this as an opportunity

01:07:53.780 | to editorialize a little bit.

01:07:56.120 | You know, there's so much made of sleep debt.

01:07:58.540 | Look, there isn't an IRS equivalent for sleep.

01:08:01.480 | They're not going to come around

01:08:02.560 | and try and collect all the sleep that you didn't get.

01:08:05.500 | No one really knows what the consequences

01:08:09.080 | are going to be for you and for me

01:08:10.840 | and for the next person for the sleep you didn't get.

01:08:13.020 | You can't really recover the sleep you missed out on,

01:08:16.900 | but you also don't want to get

01:08:18.400 | neurotically attached to a schedule

01:08:19.940 | because there's this thing called sleep anxiety

01:08:21.700 | and then people have trouble falling asleep

01:08:23.180 | and staying asleep.

01:08:24.080 | So I want to spend a moment on that

01:08:25.840 | and go back to a theme that I've said many times before,

01:08:29.200 | because these tools work.

01:08:30.960 | What I called NSDR, non-sleep-depress,

01:08:33.440 | so this would be hypnosis.

01:08:35.240 | I gave you the link, but I'll say it again,

01:08:37.360 | reveriehealth.com for clinically tested, research tested,

01:08:41.440 | free hypnosis for anxiety, but also for sleep.

01:08:46.440 | Those are very beneficial people.

01:08:48.140 | NSDR protocols, non-sleep-depress protocols

01:08:50.420 | for things like yoga nidra.

01:08:53.140 | I provide some links to those in the caption for episode two.

01:08:56.280 | These things really work.

01:08:57.240 | Last night I woke up, I went to bed about 1030.

01:09:00.200 | I woke up at three in the morning.

01:09:02.120 | I knew I wasn't feeling rested.

01:09:04.360 | I did a NSDR protocol.

01:09:07.200 | I fell back asleep.

01:09:08.280 | I woke up at 630, okay?

01:09:10.520 | You need to teach your brain and your nervous system

01:09:13.440 | how to turn off your thoughts and go to sleep.

01:09:15.700 | And ideally you do that without medication

01:09:17.340 | unless there's a real need.

01:09:18.740 | You do that through these behavioral protocols.

01:09:20.360 | They work because they involve using the body

01:09:23.720 | to shift the mind, not trying to just turn off your thoughts

01:09:26.000 | in the middle of the night.

01:09:27.420 | Now, there are periods of life where things are stressful

01:09:30.000 | and people are concerned and you will have some struggle

01:09:32.840 | getting and staying asleep.

01:09:35.240 | And that really has to do more with anxiety,

01:09:39.020 | which NSDR protocols also can help with.

01:09:42.520 | As I always say, do them in the middle of the night

01:09:43.960 | if you wake up and you want to go back to sleep,

01:09:45.420 | do them in the middle of the day

01:09:46.260 | to teach your nervous system how to calm down

01:09:47.520 | or do them first thing in the morning

01:09:48.560 | if you didn't feel you got enough sleep.

01:09:49.800 | In other words, do them whenever you have an opportunity

01:09:52.080 | to do them because they really can help you learn

01:09:55.960 | how to turn on the parasympathetic/calming arm

01:10:00.200 | of your autonomic nervous system.

01:10:01.800 | There's no other way that I'm aware of to teach your system

01:10:06.960 | to slow down and turn off your thoughts

01:10:08.680 | and go back to sleep.

01:10:09.520 | But these are powerful protocols

01:10:10.680 | and there's a lot of research now to support the fact

01:10:13.040 | that they can really help.

01:10:15.120 | Meditation would be another example.

01:10:17.060 | Meditation of certain kinds of meditation

01:10:20.880 | involve focus and alertness.

01:10:23.160 | Those are slightly different than meditations

01:10:25.140 | that involve lack of focus and attention

01:10:27.720 | to say internal states.

01:10:29.240 | I'm going to pause there.

01:10:31.620 | And then I want to talk about kids and the elderly.

01:10:34.040 | In other words, how do we control sleep

01:10:37.620 | and circadian rhythms and wakefulness in babies,

01:10:40.760 | adolescents, teens, and aged folks?

01:10:44.840 | All right, before we talk about sleep and kids,

01:10:49.040 | I want to tell a little story.

01:10:50.620 | It's not a joke.

01:10:52.040 | Many of you will be relieved that I'm not going to try

01:10:53.720 | and tell another joke this episode,

01:10:55.680 | which is the relationship between light,

01:10:59.300 | skin and pelage color,

01:11:02.680 | dopamine and reproduction, mating.

01:11:08.860 | So many seasonally breeding animals,

01:11:14.000 | Siberian hamsters, which I mentioned earlier,

01:11:16.040 | rabbits, fox, other animals change their color

01:11:20.440 | of their coat.

01:11:22.040 | In the winter, they tend to be a lighter color,

01:11:24.140 | sometimes pure white,

01:11:26.700 | sometimes with flecks of black or brown.

01:11:29.080 | And in the summer, their pelage changes

01:11:33.440 | to a color of brown or red,

01:11:36.480 | some other vastly different color.

01:11:38.420 | That shift is controlled by light and by melatonin.

01:11:43.580 | This has an interesting correlate in humans.

01:11:48.680 | So humans obviously have different skin tones

01:11:52.640 | just genetically because of the amount of melanin

01:11:56.160 | in one's skin, depending on genetic background.

01:11:59.180 | But of course, sunlight will increase the amount of melanin

01:12:03.600 | in the skin regardless, right?

01:12:05.640 | This is suntan, sunburn, et cetera, bronzing, whatever.

01:12:09.400 | The whole system is wired so that shifts in skin color

01:12:16.520 | and shifts in these cells within the eye and melatonin

01:12:20.920 | are actually very closely linked.

01:12:22.440 | So here's the story.

01:12:23.460 | Many years ago, meaning about 10 years ago, 15 years ago,

01:12:29.880 | let's see, it was 20 years ago, forgive me,

01:12:35.040 | a guy named Iggy Provencio,

01:12:37.240 | who was running his own lab at Uniformed Armed Services,

01:12:42.240 | this is a standard biological laboratory,

01:12:45.040 | discovered that there was an opsin in the eye,

01:12:50.040 | in the cells of the eye that connect

01:12:51.640 | to the rest of the brain called melanopsin.

01:12:54.320 | Melanopsin, as many of you now know, is the opsin,

01:12:57.120 | it's like a pigment, it absorbs light.

01:12:59.800 | It is the opsin that converts light into electrical signals

01:13:03.680 | that then set the circadian clock.

01:13:05.320 | Iggy discovered melanopsin because it was similar in form

01:13:14.040 | to what was in frog melanophores.

01:13:18.680 | It was actually in the skin of frogs

01:13:20.980 | that allowed those frogs to go from pale white

01:13:24.720 | when it was dark for most of the 24-hour cycle

01:13:28.280 | to pigmented, green or brown for a frog.

01:13:33.100 | So there's this relationship between the cells in our eye

01:13:37.820 | and the pigment cells of our skin.

01:13:40.540 | And we also know that in long days there's more breeding.

01:13:44.280 | How does that work?

01:13:45.120 | Well, that's actually from dopamine

01:13:47.500 | triggering increases in testosterone,

01:13:50.260 | mainly in males and estrogen mainly in females,

01:13:52.980 | although of course there's testosterone and estrogen

01:13:55.400 | in both sexes.

01:13:57.180 | So we have this kind of pathway where it's light,

01:14:01.420 | increases in melanin, dopamine and reproduction

01:14:04.780 | on the one hand and lack of light,

01:14:07.040 | melatonin decreases in the darkness of skin,

01:14:11.840 | less melanin in the skin or in the case of an animal

01:14:15.520 | with white fur and no reproduction on the other hand.

01:14:18.760 | And humans don't actually shift their breeding patterns

01:14:24.780 | tremendously from long days and short days,

01:14:28.400 | although there are some data that there's some shifts.

01:14:31.640 | We also don't radically change our skin color

01:14:34.560 | depending on how much sunlight exposure we have.

01:14:37.560 | But the simple way to put this is when days are long,

01:14:41.680 | there's a lot more dopamine and we feel really good

01:14:44.760 | and there's a lot more breeding and breeding like behavior.

01:14:47.960 | When days are short, there's a lot less dopamine

01:14:51.680 | and a lot less breeding behavior

01:14:53.420 | because these pathways are very highly conserved.

01:14:57.640 | Now what's interesting is that as we've moved

01:15:02.200 | into a modern society where much of our waking days,

01:15:06.240 | we are looking at screens, which is fine

01:15:08.040 | 'cause we're getting a lot of light that way,

01:15:09.400 | although not as much as sunlight.

01:15:11.140 | But also at night, we're getting a lot of light from screens.

01:15:15.500 | What's happened is all these pathways, melanin in the skin,

01:15:20.440 | turnover of skin cells, dopamine,

01:15:23.080 | all of this stuff has become completely disrupted.

01:15:26.640 | Now that's not to say that we should go back to a time

01:15:28.640 | in which we didn't use artificial lights.

01:15:30.600 | But I think the important thing to realize

01:15:32.400 | is that feeling good with getting a lot of light,

01:15:36.320 | the relationship to dopamine and melanin in the skin

01:15:42.560 | and the good feelings of getting light also on our skin

01:15:46.440 | provided you're not getting burned

01:15:48.000 | or you're not getting excessive UV exposure,

01:15:50.560 | those are not just coincidences.

01:15:53.160 | Those are hardwired biological mechanisms

01:15:55.400 | that exist in everybody regardless of how light or dark

01:15:58.620 | your skin is to begin with.

01:16:00.960 | There's another point which is important,

01:16:03.240 | which is that the dopamine system,

01:16:05.760 | which is this feel-good molecule is very closely related

01:16:09.900 | to the testosterone and estrogen and reproductive cycles.

01:16:12.700 | Remember, melatonin inhibits gonadotropin-releasing hormone,

01:16:16.640 | luteinizing hormone and the production of these hormones

01:16:19.460 | and melatonin is the effector.

01:16:21.520 | It is the hormone of darkness.

01:16:24.440 | So I just threw a lot of biology at you

01:16:27.920 | and I'm not saying you're like a Siberian hamster,

01:16:30.820 | at least not in ways that I'm aware of.

01:16:32.800 | I'm not saying that your pelage color is going to change.

01:16:36.120 | Actually, the reason people go gray

01:16:37.840 | is because when you're really stressed, did you know this?

01:16:40.760 | When you're really stressed,

01:16:42.440 | there's an increase in the nerve fibers

01:16:44.680 | that release adrenaline to the hair follicle

01:16:48.320 | and that activates peroxide groups in the hair follicle

01:16:52.860 | that cause the hair to actually go gray or white.

01:16:55.600 | So actually, stress does make your hair gray or white.

01:16:58.760 | Aging does it too.

01:16:59.840 | That was a brief aside,

01:17:03.140 | but for those of you that are interested

01:17:04.820 | in the relationship between light and skin tone

01:17:07.640 | and all that kind of stuff,

01:17:08.480 | I thought you might find it interesting

01:17:09.520 | that these cells in your eye are a lot like

01:17:11.960 | these skin cells in frogs or in animals

01:17:15.360 | that shift their entire color and sometimes metamorphosize.

01:17:20.360 | There are some species that literally change shape

01:17:22.500 | in the reproductive organs.

01:17:23.480 | In fact, if that wasn't weird enough,

01:17:25.940 | when I was in graduate school at Berkeley,

01:17:27.680 | there was another graduate student studying a species

01:17:30.880 | of hermaphroditic mole, those little things that dig,

01:17:35.320 | hermaphroditic mole that would change from having ovaries

01:17:39.760 | to testes and back again, depending on day life.

01:17:43.880 | Super cool, super different and wild biological mechanism.

01:17:48.880 | If you're wondering how those animals reproduce,

01:17:52.880 | they actually adjust the numbers of males and females,

01:17:55.020 | depending on the density of males and females.

01:17:56.760 | So if they're too many males,

01:17:59.280 | some of the males turn their testes into ovaries.

01:18:02.920 | And if they're too many females,

01:18:03.960 | they turn their ovaries into testes.

01:18:05.640 | They actually are true hermaphroditic animals

01:18:08.640 | as opposed to pseudo hermaphroditic animals.

01:18:10.840 | Okay, let's get back on track.

01:18:13.940 | Let's talk about the animal that most of you care about,

01:18:17.160 | which is the human animal, new parents and babies.

01:18:22.120 | All right, as I mentioned earlier,

01:18:23.600 | melatonin is not cyclic, it's not cycling in babies,

01:18:28.440 | it's more phasic, it's being released

01:18:30.720 | at a kind of a constant level.

01:18:32.700 | And babies tend to be smaller than adults, they are.

01:18:35.920 | And so those concentrations of melatonin are very high.

01:18:38.740 | As a baby grows, those concentrations per unit volume

01:18:41.680 | are going to go down.

01:18:42.740 | Babies are not born with a typical sleep-wake cycle.

01:18:47.320 | And now all the parents saying,

01:18:48.860 | "Tell me something I didn't know."

01:18:51.680 | They also have, and I really want to emphasize this,

01:18:55.440 | they also have much more sensitive optics of the eye.

01:18:59.780 | So a number of people have asked me,

01:19:02.180 | should I be exposing my baby to sunlight?

01:19:04.780 | You don't want to avoid sunlight,

01:19:06.240 | but their eyes are very sensitive,

01:19:08.240 | the optics of their eyes aren't quite developed,

01:19:10.560 | so much so that when you look at a newborn baby

01:19:14.520 | and they look a little glassy-eyed

01:19:16.720 | and they're kind of looking through you,

01:19:17.760 | or even a young child,

01:19:19.100 | a lot of people think that they're seeing you

01:19:21.600 | the way that you're seeing them.

01:19:23.080 | Hate to break it to you,

01:19:24.080 | but if you ever can just Google a visual image

01:19:29.080 | of like a one-month-old,

01:19:32.240 | the optics of their eyes are so poor

01:19:34.360 | that you're a cloudy image.

01:19:35.960 | They're not seeing your fine detail.

01:19:38.180 | As the optics get better,

01:19:39.840 | then they will see you with more and more clarity.

01:19:43.280 | But a lot of that is clearing of the lens

01:19:45.060 | and some of the other aqueous features of the newborn eye.

01:19:48.880 | They don't see very well.

01:19:51.320 | But they also don't have such great ways

01:19:54.260 | of adjusting to bright light.

01:19:55.700 | And so babies have a natural aversion to bright light,

01:19:58.320 | so you really want to avoid trying to use

01:20:01.080 | sunlight or really bright light

01:20:02.360 | in the same way that you would for an adult

01:20:04.240 | on a young baby or child.

01:20:06.920 | As children get older, however,

01:20:10.120 | melatonin does start to become slightly more cyclic,

01:20:13.160 | slightly more cycled,

01:20:14.400 | and their body temperature rhythms

01:20:15.920 | also start to fall into a more regular,

01:20:19.280 | not quite 24-hour rhythm.

01:20:20.920 | They're more of these ultradian rhythms.

01:20:22.480 | So in an episode,

01:20:24.000 | I think it was one or two of the podcast or maybe both,

01:20:27.360 | we talked about these 90-minute so-called ultradian rhythms

01:20:30.800 | where every 90 minutes,

01:20:33.200 | babies are going through a cycle of body temperature

01:20:37.640 | and some other hormonal features.

01:20:39.160 | I mean, so much is changing in their system.

01:20:42.060 | So what to do if a child isn't sleeping?

01:20:45.640 | You can use phases of darkness and phases of light,

01:20:49.440 | but they're going to have to be shortened

01:20:50.880 | in order to try and encourage sleep

01:20:52.440 | when you want the child to sleep.

01:20:53.600 | It's not that they're just not going to fall

01:20:55.680 | into an adult-like regime of a temperature minimum

01:20:58.740 | and a temperature maximum.

01:21:00.120 | Their temperature minimums and maximums

01:21:01.680 | are fluctuating much more quickly,

01:21:03.800 | and it varies tremendously.

01:21:05.380 | Actually, there's an interesting literature

01:21:08.680 | of whether or not they have siblings,

01:21:10.040 | whether or not they're twins,

01:21:11.000 | whether or not they're in a nursery environment,

01:21:13.120 | whether or not they're alone.

01:21:14.800 | Hopefully the baby's not alone, but you know what I mean,

01:21:16.380 | that they're sleeping alone in a room

01:21:17.600 | while you're in the other room.

01:21:19.640 | There are a couple of things that seem to help,

01:21:21.620 | which is getting the overall environment

01:21:23.460 | into a 24-hour schedule.

01:21:25.200 | So having the room slightly colder,

01:21:27.840 | obviously you want babies to be nice and cozy,

01:21:29.960 | slightly colder when you would like them to be asleep,

01:21:32.740 | slightly warmer for the times

01:21:34.120 | you would like them to be awake.

01:21:35.120 | Babies tend to run pretty hot anyway.

01:21:38.000 | And obviously you want to be very careful

01:21:43.000 | about avoiding all extremes of temperature, cold or hot.

01:21:48.000 | So if they're going through these 90-minute cycles,

01:21:50.980 | you're going to have to adjust

01:21:52.240 | to those 90-minute cycles as well.

01:21:53.800 | So then people say, well, that's not going to help me at all

01:21:55.800 | because how do I deal with the fact

01:21:57.280 | that I need to be up every 90 minutes at night?

01:21:59.440 | There are a couple tools that can be helpful.

01:22:02.160 | The first one is going to be

01:22:04.440 | to try and understand the relationship

01:22:07.100 | between calm and deep sleep.

01:22:09.640 | So the autonomic nervous system can put us into states

01:22:12.860 | of panic where that kind of seesaw of autonomic alertness

01:22:16.700 | goes all the way to panic,

01:22:18.040 | or it can be alertness or it can be alert and calm, right?

01:22:20.560 | So there's a range there.

01:22:22.040 | It's a continuum.

01:22:23.140 | It can also be that you're in deep sleep,

01:22:26.040 | so the other end of the seesaw is way up,

01:22:27.720 | or you're in light sleep, or you're kind of sleepy,

01:22:30.080 | or you're just feeling kind of relaxed.

01:22:32.140 | Perhaps the most important thing

01:22:36.280 | if you're having to map to a baby's schedule

01:22:39.520 | in order to make sure that they're getting changings

01:22:41.780 | in nursing, et cetera, at the appropriate times,

01:22:44.340 | is to try and maintain,

01:22:48.360 | if you can't sleep or you can't sleep continuously,

01:22:51.840 | to try and maintain your autonomic nervous system

01:22:56.040 | in a place where you're not going into heightened states

01:22:59.340 | of alertness when you would ideally be sleeping.

01:23:03.100 | Now, I realize that this could be translated

01:23:05.920 | to try and stay calm while you're sleep deprived,

01:23:07.880 | which is very hard for people to do,

01:23:10.000 | but this is where the non-sleep deep breath protocol

01:23:12.920 | surface again and can potentially be very beneficial

01:23:16.120 | for people to be able to recover, not necessarily sleep,

01:23:19.940 | but for them to maintain a certain amount

01:23:22.360 | of autonomic regulation.

01:23:23.980 | So what would this look like?

01:23:25.060 | This would look like a baby goes down,

01:23:27.200 | maybe it's only going to go down for 45 minutes.

01:23:29.560 | If you can capture sleep,

01:23:31.440 | capture sleep, there are some data showing

01:23:34.640 | what's called polyphasic sleep.

01:23:35.960 | If you can sleep in 45 minute increments or batches,

01:23:38.980 | even if it's spread throughout the day

01:23:40.620 | with periods of wakefulness in between,

01:23:42.120 | as miserable as that sound,

01:23:43.240 | there are actually some adults

01:23:44.140 | that have deliberately employed that

01:23:46.080 | who don't have children for sake of work productivity.

01:23:49.260 | And it does tend to reduce the total overall amount

01:23:51.880 | of sleep that you need.

01:23:53.540 | It is a very hard schedule for most people to maintain,

01:23:55.780 | but if you have a baby, the baby may be throwing you

01:23:57.540 | into that kind of schedule anyway.

01:23:58.840 | So if you can get 45 minutes sleep while they sleep, great.

01:24:02.040 | If you can get another 45 minutes after waking

01:24:03.960 | and then they go back down to sleep, great.

01:24:05.800 | So as many phases of sleep as you can get,

01:24:07.800 | but if you can't sleep,

01:24:09.600 | the data on non-sleep deep rest type protocols

01:24:12.480 | does show that at least from a neurochemical level,

01:24:15.460 | want to be clear what that means,

01:24:16.820 | reset of things like dopamine levels in the basal ganglia

01:24:20.440 | measured by things like positron emission tomography,

01:24:22.800 | et cetera, those things tend to reset themselves pretty well

01:24:26.640 | if you can access these deep rest states.

01:24:29.140 | So that means not being alert

01:24:32.280 | throughout the entire time that the baby is sleeping,

01:24:34.200 | trying to sort of mirror the baby's sleep cycle,

01:24:37.420 | which can be brutal for certain people.

01:24:39.040 | And especially if you're trying to prepare meals

01:24:40.820 | and do all these things.

01:24:41.660 | So I do recognize that there are a lot of constraints

01:24:43.380 | on parenting, not just mapping

01:24:44.560 | on your baby's sleep schedule.

01:24:46.360 | As children approach ages one, two, three, four,

01:24:50.960 | that's when certainly the optics of the eyes have improved,

01:24:54.440 | but you don't want to damage the eyes, of course,

01:24:56.440 | with very bright light.

01:24:57.960 | They are much more sensitive

01:24:59.600 | even until they're kind of 10, 11 years old.

01:25:02.940 | And we'll talk about vision in children in a moment,

01:25:06.440 | but trying to get longer and longer batches of sleep

01:25:10.980 | through, hopefully not through the use

01:25:13.240 | of administering melatonin to the kids,

01:25:15.420 | 'cause that's what I talked about before,

01:25:17.740 | why that could potentially be detrimental.

01:25:19.540 | Talk about that with your doctor.

01:25:21.100 | But more so trying to get longer blocks of sleep

01:25:25.840 | that map onto these ultradian cycles.

01:25:27.980 | So it would be better off to get a three hour,

01:25:30.580 | like two 90 minute cycles,

01:25:32.060 | than a four hour batch of sleep

01:25:34.240 | because waking up in the middle of those ultradian cycles

01:25:36.820 | can just be brutal for parent and kid.

01:25:39.440 | So if one can't get a full six or 10

01:25:42.800 | or some kids should even be sleeping 12 hours

01:25:44.620 | when they're growing quickly,

01:25:45.800 | trying to get batches of sleep,

01:25:47.900 | even if they're fractured throughout the 24 hour cycle,

01:25:51.020 | that are matched more to these 90 minute cycles,

01:25:53.980 | meaning maybe one ultradian cycle of 90 minutes

01:25:56.620 | or two back-to-back or three back-to-back-to-back,

01:26:01.060 | that's going to be better

01:26:02.020 | than waking up in the middle of an ultradian cycle.

01:26:04.240 | It's just going to set any number of other things

01:26:06.860 | in a better direction than were you to try to say,

01:26:10.740 | just enforce or force a full eight or 10 hours of sleep.

01:26:15.020 | That's at least what the literature shows.

01:26:17.380 | Some kids sleep great through the night,

01:26:19.160 | starting at a very young age, others don't.

01:26:20.920 | I typically hear from people

01:26:22.420 | who are struggling tremendously.

01:26:24.320 | They're losing their mind, understandably,

01:26:26.320 | because they're not sleeping, their kid's not sleeping,

01:26:29.480 | or their kid is sleeping for such brief periods.

01:26:31.280 | So in other words, try and access deep calm

01:26:33.660 | if you can't sleep.

01:26:34.500 | Try and access sleep if you can sleep,

01:26:35.900 | even if it's fractured.

01:26:37.220 | And then you say, well, what about all the sunlight viewing

01:26:39.440 | and the exercise stuff?

01:26:40.700 | When sleep is really, really dismantled,

01:26:45.940 | meaning it's happening in various times of day or night,

01:26:49.420 | that's especially, at those times,

01:26:52.600 | it's going to be especially important for the parent

01:26:54.960 | to get morning and evening sunlight

01:26:56.620 | because your circadian clock is going into a tailspin

01:26:59.680 | and it basically wants to anchor to something.

01:27:01.720 | So you want to give it two anchors,

01:27:02.900 | morning and evening light, okay?

01:27:05.320 | So this is rather different

01:27:07.560 | than what I described for shift work.

01:27:09.180 | This is when things are really chaotic

01:27:10.780 | and you're just not able to sleep.

01:27:12.060 | Similar circumstances can arise

01:27:13.600 | if you're taking care of a very sick loved one,

01:27:15.500 | you're up all night.

01:27:16.840 | Try and stay calm using NSDR protocols.

01:27:19.420 | I know it's harder to do than to say,

01:27:22.620 | but those protocols are there, they're free.

01:27:24.900 | There's research to support them.

01:27:26.620 | Try and get sleep whenever you can,

01:27:28.620 | but also try to get morning sunlight

01:27:31.900 | and evening sunlight in your eyes if you can.

01:27:34.180 | And if you can't get that, use artificial light, okay?

01:27:37.580 | What about later life?

01:27:39.940 | So kids now, adolescents, teens,

01:27:42.160 | it is true that teens have a tendency to wake up later

01:27:46.260 | and go to sleep later.

01:27:47.700 | In part, just because they're sleeping a lot more,

01:27:50.560 | they're churning out gonadotropin-releasing hormone

01:27:52.780 | and luteinizing hormone, their whole bodies are changing.

01:27:56.340 | I don't know whether or not people realize this,

01:27:58.420 | but the fastest rate of aging

01:28:00.460 | that any of us will ever undergo is puberty.

01:28:03.480 | That is the fastest rate of aging.

01:28:06.060 | And so there's a huge number of biological processes

01:28:08.620 | that are happening during puberty.

01:28:10.140 | Probably devote a whole episode to,

01:28:12.180 | puberty is a fascinating aspect to the life course,

01:28:16.660 | but it is an accelerated period of aging.

01:28:19.360 | And the circadian clock mechanisms

01:28:21.460 | sometimes are very intact

01:28:24.500 | and sometimes they're a little dismantled

01:28:25.920 | and going through some change,

01:28:27.700 | but prioritize the duration of sleep

01:28:31.260 | for adolescents and teens.

01:28:33.020 | Now, if that means they're sleeping until 2 p.m.

01:28:34.980 | and then waking up and then they're up all night,

01:28:36.680 | the up all night part can become a problem,

01:28:38.540 | especially with all the devices texting in their rooms

01:28:41.300 | or playing video games.

01:28:43.220 | Morning and evening sunlight would be ideal,

01:28:45.080 | but some kids are just going to sleep

01:28:46.480 | through the morning sunlight.

01:28:47.800 | However, if you were to measure their temperature,

01:28:49.640 | what you would find is that their temperature minimum

01:28:52.140 | would come later in the morning.

01:28:54.100 | It's not going to be 8 a.m.,

01:28:57.100 | it's going to be maybe even 10 a.m.

01:28:58.640 | if they're sleeping until 11 or 12,

01:29:01.200 | or it might be 8 a.m. if they're sleeping until 10.

01:29:03.860 | Remember, temperature minimum is two hours

01:29:05.500 | before your average waking time, typically.

01:29:08.300 | So in teens, it maximizes the total amount of sleep.

01:29:11.220 | Try and get regular sunlight

01:29:13.020 | either in the morning or in the evening or both,

01:29:15.540 | but if they're sleeping through the morning sunrise,

01:29:17.240 | that's probably not as much of an issue.

01:29:20.440 | Waking them up and depriving them of sleep is probably worse

01:29:23.360 | because their T-min, their temperature minimum,

01:29:25.740 | is actually falling later.

01:29:27.960 | So their circadian dead zone is later, et cetera.

01:29:30.760 | So I think with adolescents and teens,

01:29:32.740 | it makes sense to kind of give them a little bit more rope

01:29:35.940 | in terms of allowing them some leeway

01:29:39.060 | to adjust their own schedule.

01:29:40.160 | Some schools are even starting classes later

01:29:42.200 | on the basis of some very good biology

01:29:45.080 | to support this late shifted rhythm

01:29:46.860 | and this extended sleep phase.

01:29:48.500 | There are data from Dr. Jamie Zeitzer,

01:29:53.220 | Department of Psychiatry and Behavioral Sciences,

01:29:54.860 | and others at Stanford showing that turning on the lights

01:29:57.660 | in the room of a teen before they wake up

01:29:59.780 | helps them get more sleep the subsequent night.

01:30:03.660 | It also tricks them into going to sleep

01:30:05.300 | a little bit earlier,

01:30:06.120 | but it gives them about 45 minutes more of deep sleep,

01:30:09.260 | and that's been shown statistically.

01:30:10.980 | Total sleep time increases as well.

01:30:13.340 | If they're hiding under the covers, that's not going to work

01:30:15.140 | but their eyes don't have to be open.

01:30:17.040 | I know a few parents now that are coming in

01:30:18.880 | with a flashlight and flashing their kids over their eyelids

01:30:22.760 | before they wake up in hopes of getting this to work.

01:30:24.940 | Some have told me this is working.

01:30:27.320 | That's not part of a standard study,

01:30:29.680 | but it does seem to work because, now you should know why,

01:30:35.040 | because if light's getting through the eyelids

01:30:37.200 | and it's say 8 a.m. and the kid is still asleep

01:30:40.400 | and they're going to wake up at 10,

01:30:41.800 | you're giving them light just after

01:30:44.920 | or around their temperature minimum,

01:30:47.340 | which is going to make them want to go to sleep earlier.

01:30:50.120 | And in the case of teens, for some reason,

01:30:52.080 | we don't quite understand sleep longer,

01:30:54.620 | about 45 minutes longer, spend more time in deep sleep.

01:30:57.280 | Adults can do this too.

01:30:58.320 | If you can persuade someone or put your lights on timer

01:31:00.660 | for lights to go on before you wake up,

01:31:02.960 | that's really going to help you wake up earlier, okay?

01:31:06.200 | So if you're starting to hear some themes

01:31:08.920 | are really resounding over and over again,

01:31:11.160 | that should be reassuring to you, right?

01:31:13.360 | These are core mechanisms.

01:31:15.740 | Fortunately, there aren't a thousand different mechanisms.

01:31:18.700 | Now, in the elderly, there's a real tendency

01:31:23.260 | to want to go to sleep very early and wake up very early.

01:31:27.300 | And people should talk to their physician.

01:31:31.220 | There is some evidence that melatonin levels

01:31:33.820 | and patterns of melatonin secretion

01:31:36.180 | can become a little chaotic in elderly folks.

01:31:39.640 | What do I mean by elderly?

01:31:40.660 | Well, it's going to differ.

01:31:41.540 | Rates of aging differ, right?

01:31:42.980 | You see some 65-year-olds that are struggling

01:31:45.220 | to move and seem much older than some 65-year-olds

01:31:50.060 | that are still hustling around and have tons of energy.

01:31:53.540 | There's a lot of variation.

01:31:55.100 | Some of it's genetic, some of it's lifestyle factors.

01:31:57.900 | It really varies.

01:32:00.700 | Certainly lifestyle factors can play an important role

01:32:03.460 | in rates of aging.

01:32:04.660 | I think that the most prominent results

01:32:09.780 | from sleep and circadian rhythms in the elderly

01:32:12.860 | are they need to get as much natural light,

01:32:15.780 | even if it's through windows.

01:32:16.940 | I realized that some elderly folks

01:32:19.180 | can't get outside as easily.

01:32:20.740 | It's not safe for them to do it.

01:32:21.980 | They can't move around as easily.

01:32:23.960 | Exercise can come in various forms

01:32:26.940 | for people that can't get outside

01:32:29.380 | and get a ton of sunlight by jogging or cycling.

01:32:32.100 | They're not able to do that.

01:32:33.340 | Light through a window in that case, open window ideally,

01:32:35.820 | but for temperature reasons, et cetera,

01:32:37.700 | sometimes the window has to be closed.

01:32:39.500 | Getting people near that window

01:32:40.840 | and away from artificial light early in the day

01:32:43.580 | and away from artificial lights during the night phase

01:32:46.740 | can have a tremendous effect.

01:32:49.440 | And in the elderly, that's when melatonin

01:32:52.180 | might be a viable option.

01:32:55.180 | And this should be discussed with a physician, of course,

01:32:57.020 | but you're way past the puberty time point.

01:33:00.920 | In most cases, people who are in their 70s and 80s and 90s

01:33:05.000 | are not churning out a lot of GnRH

01:33:07.000 | and luteinizing hormone to begin with.

01:33:09.060 | And that's where struggles with falling asleep

01:33:11.540 | and staying asleep, all the same parameters

01:33:14.140 | and things we've described before still apply,

01:33:17.300 | light, exercise, temperature, et cetera,

01:33:19.560 | but that's where melatonin might be of greatest benefit.

01:33:22.960 | And again, I'm not pushing melatonin here,

01:33:24.680 | but I think for elderly folks who are having trouble

01:33:26.920 | falling and staying asleep, that might be worthwhile.

01:33:29.740 | I should just also mention that regular schedule

01:33:36.000 | for folks that are elderly and as much natural light

01:33:39.400 | is safely possible, those are going to be the really,

01:33:42.200 | the key levers for adjusting sleep in circadian schedules.

01:33:46.180 | I've mentioned before in previous podcasts,

01:33:49.440 | other supplements besides melatonin.

01:33:52.400 | And some of those supplements are quite good for sleep.

01:33:55.100 | I'm not a supplement pusher.

01:33:56.600 | I am somebody who takes supplements.

01:33:59.360 | I believe in them.

01:34:00.280 | Some have worked for me, some have not worked as well,

01:34:03.840 | but I certainly believe in getting the behaviors right,

01:34:07.800 | whether or not it's NSDR protocols, viewing natural light,

01:34:11.000 | exercise, it's hot baths or cold showers or what have you,

01:34:15.760 | behavioral protocols first.

01:34:18.120 | There are some supplements

01:34:19.160 | that I've mentioned in previous podcasts,

01:34:20.960 | but I've seemed to get a lot of questions about.

01:34:22.600 | So I just want to take a couple of minutes

01:34:23.680 | and just talk about some of the supplements

01:34:25.520 | that can be beneficial for helping turn it off thinking,

01:34:29.220 | accessing deeper sleep, and even being able

01:34:32.640 | to compact your sleep schedule

01:34:33.860 | into a shorter period of hours,

01:34:35.200 | meaning getting by well with less sleep.

01:34:37.600 | People take a lot of sleeping pills.

01:34:39.560 | I'm not going to tell people not to take sleeping pills.

01:34:42.280 | They can be very problematic, habit forming,

01:34:44.560 | high side effect incidents in many cases.

01:34:49.360 | Some people can handle them just fine.

01:34:52.000 | Again, I'm not a physician, I don't prescribe anything,

01:34:55.840 | a professor, so I profess a lot of things,

01:34:58.240 | some of which are my opinion.

01:34:59.780 | Although if you look at the scientific literature,

01:35:02.060 | there's some impressive data

01:35:03.580 | around some non-prescription drug type supplements

01:35:06.780 | that have fairly high safety margins that you might consider

01:35:10.140 | but you should talk to your doctor always

01:35:11.900 | before adding or taking anything

01:35:13.720 | out of your health regimes, right?

01:35:15.700 | Your health is not my responsibility,

01:35:17.440 | it's your responsibility, so be a stringent filter.

01:35:20.200 | Along those lines, one of the most powerful

01:35:22.240 | and useful tools that I've mentioned here on many times

01:35:24.440 | and I plan to mention many, many more times

01:35:26.560 | is the website examine.com,

01:35:29.600 | which I have no affiliation with,

01:35:31.800 | but is a wonderful site that links you

01:35:33.680 | to quality peer-reviewed studies

01:35:35.820 | related to just about any supplement,

01:35:38.360 | including some safety warnings.

01:35:40.440 | We'll also tell you what subjects,

01:35:41.940 | whether or not it was rats, cats, elderly folks, or kids,

01:35:45.440 | that a given study was done on,

01:35:47.100 | which is important, can be kind of hard to pull

01:35:49.080 | from sites where people are just advertising supplements,

01:35:52.480 | right, they usually don't tell you what the study was

01:35:54.660 | and who were these rats, who were these kids, et cetera.

01:35:59.120 | There are three supplements that, at least for me,

01:36:04.120 | have had a tremendously positive effect on my sleep

01:36:08.120 | that some of you might consider.

01:36:10.200 | I would say if you're doing everything properly,

01:36:14.840 | behaviorally, and you're still having issues,

01:36:17.200 | then supplements might be a good thing for you.

01:36:19.840 | Or if you are traveling and you want a little bit

01:36:22.380 | of extra help in buffering your sleep wakefulness protocols.

01:36:27.280 | Some people like to go just to the supplements.

01:36:29.120 | They're like, what should I take?

01:36:30.060 | I have people in my life that are like,

01:36:32.040 | just tell me what to take.

01:36:33.200 | I'm more of, here's what you might want to do or not do,

01:36:36.000 | but, and then think about what you might want to take

01:36:38.520 | or not take, but personal preference and it's free country,

01:36:42.700 | so you can do what you like.

01:36:45.080 | Magnesium.

01:36:48.780 | So magnesium has been shown to increase the depth of sleep

01:36:53.280 | and has been shown to decrease the amount of time

01:36:56.600 | that it takes to access sleep, to fall asleep.

01:36:59.900 | It comes in various forms.

01:37:01.640 | I've talked a bunch of times about magnesium threonate,

01:37:04.920 | T-H-R-E-O-N-A-T-E, threonate,

01:37:09.160 | which seems to be the more bioavailable form of magnesium.

01:37:13.160 | And magnesium threonate, it seems,

01:37:16.420 | is shuttled preferentially to the brain,

01:37:19.360 | which is where you want it.

01:37:21.880 | And there are certain transporters,

01:37:23.640 | it actually engages the GABA pathway,

01:37:26.060 | which tends to turn off certain areas of the forebrain,

01:37:28.300 | allows you to fall asleep.

01:37:30.140 | There is a study, if you would like to explore it,

01:37:34.060 | since people serious about supplementation

01:37:36.500 | might want to explore the study,

01:37:38.320 | which is Ates et al., A-T-E-S,

01:37:41.020 | dose-dependent absorption profile

01:37:42.560 | of different magnesium compounds.

01:37:44.960 | Looks to me like a quality peer-reviewed paper.

01:37:47.960 | I can put the link in the caption.

01:37:50.200 | And it explores all the different forms of magnesium.

01:37:53.960 | It does seem like magnesium glycinate

01:37:56.080 | can be similar to magnesium threonate

01:37:57.820 | in terms of which tissues it shuttled to.

01:37:59.540 | Magnesium malate, M-A-L-A-T-E,

01:38:02.320 | is preferentially shuttled to the muscle, it appears,

01:38:04.500 | as opposed to the brain.

01:38:05.340 | So it's going to be more of a muscle repair type thing

01:38:08.260 | or restoring magnesium stores in the periphery

01:38:10.800 | as opposed to the brain.

01:38:11.900 | Magnesium citrate has another name

01:38:14.620 | that I won't mention in jest

01:38:17.240 | because magnesium citrate's main effect,

01:38:20.140 | at least on me and the people I know,

01:38:21.900 | seems to be a laxative effect

01:38:24.100 | as opposed to a cognitive effect.

01:38:25.680 | There's also some evidence

01:38:27.160 | that magnesium threonate can be neuroprotective.

01:38:29.880 | Those data come from quality labs,

01:38:32.380 | mostly rodent studies, not human studies,

01:38:34.860 | but it's kind of interesting.

01:38:36.160 | And again, the safety margins for these things

01:38:37.880 | tend to be pretty high,

01:38:39.180 | but anytime you're going to take something new,

01:38:41.040 | you should approach it with caution,

01:38:42.440 | especially since magnesium could be involved

01:38:44.640 | in heart rhythm and things of that sort.

01:38:47.320 | The other supplement that has been very beneficial for me

01:38:50.480 | is theanine, so this is T-H-E-A-N-I-N-E, theanine.

01:38:55.480 | T-H-E-A-N-I-N-E.

01:38:59.580 | Theanine activates certain GABA pathways,

01:39:02.920 | which are involved in turning off,

01:39:04.580 | top-down processing and thinking,

01:39:06.180 | making it easier to fall asleep.

01:39:08.740 | And theanine, 100 milligrams to 300 milligrams,

01:39:13.400 | has a calming effect.

01:39:15.100 | Theanine is now showing up

01:39:16.300 | in a number of different energy drinks

01:39:19.320 | and even some coffees as a way to try and get people

01:39:21.940 | to ingest more of a given type of coffee,

01:39:23.800 | 'cause the idea is it would take away the jitters

01:39:26.660 | and the anxiety, allowing people to drink more coffee.

01:39:29.660 | I'm talking about taking magnesium and theanine

01:39:33.220 | 30 to 60 minutes before bedtime,

01:39:35.020 | not during the day to quell anxiety,

01:39:37.540 | but rather 30 to 60 minutes before bedtime,

01:39:40.100 | with or without food for me has made a difference.

01:39:43.360 | And the combination of those two things has really helped.

01:39:45.900 | Theanine for sleepwalkers can be a problem.

01:39:49.180 | It does increase the intensity of your dreams.

01:39:51.600 | It gives you very vivid dreams.

01:39:53.920 | So for sleepwalkers or people that get night terrors,

01:39:56.040 | stay away from theanine is my advice.

01:39:59.100 | Magnesium, theanine might be something to explore

01:40:01.320 | for those of you that don't have those issues,

01:40:03.580 | with the emphasis on might.

01:40:05.540 | And then I've talked about a compound,

01:40:07.380 | and last time I talked about the mechanisms of apigenin,

01:40:10.560 | which is a derivative of chamomile, API, Gen,

01:40:13.880 | which acts as a little bit of a hypnotic

01:40:16.600 | by activating chloride channels, hyperpolarized neurons,

01:40:19.240 | increases GABA in the brain,

01:40:20.860 | basically makes you feel a little sleepy.

01:40:23.720 | And chamomile, for those of you that read your,

01:40:26.560 | what was it, Peter Rabbit snuck into Mr. McGregor's garden,

01:40:31.200 | ate the chamomile, fell asleep, Mr. McGregor came back.

01:40:33.720 | Okay, anyone flashing back to elementary school?

01:40:35.920 | Okay, there's a story about chamomile

01:40:38.200 | having these kind of sedative-like effects.

01:40:40.000 | Apigenin is highly concentrated.

01:40:41.480 | Chamomile also has anti-estrogenic effects.

01:40:44.500 | So if you want to keep your estrogen up,

01:40:46.740 | you might want to be cautious about apigenin.

01:40:49.140 | That's where things like examine.com become really useful,

01:40:52.140 | because you can go to examine, you put in apigenin,

01:40:54.540 | and it'll tell you all the things that it does,

01:40:56.220 | and all the things that it does

01:40:57.540 | can sometimes include things that you had no idea,

01:40:59.500 | like reducing conversion of certain androgens to estrogens,

01:41:04.500 | which you might like, or you might want to avoid.

01:41:07.540 | That's up to you and where you want your estrogen levels,

01:41:09.660 | depending on who you are

01:41:10.640 | and what your life circumstances and goals are.

01:41:14.100 | A few other things that can help the transition to sleep

01:41:18.260 | are things like 5-HTP, L-tryptophan.

01:41:20.780 | I've talked about why I'm not a fan of those for me.

01:41:23.780 | They tend to throw me into deep sleep,

01:41:25.700 | and then I wake up and I can't fall back asleep.

01:41:27.580 | So I don't like to tinker with my serotonin system.

01:41:30.360 | I don't like to tinker with my dopamine system

01:41:32.660 | for entirely other reasons,

01:41:34.140 | but none of which are particularly concerning.

01:41:38.260 | It's just that I find that if I increase my dopamine

01:41:40.340 | by taking L-tyrosine in pill form,

01:41:43.000 | then I crash really hard the next day.

01:41:44.640 | Or if I take 5-HTP or L-tryptophan,

01:41:47.000 | I fall deeply asleep and then I wake up.

01:41:49.720 | But I did mention that there might be ways

01:41:51.880 | to make sleep more compact.

01:41:53.840 | And so this is actually a request to you.

01:41:56.160 | I had a really interesting experience when I was a postdoc.

01:42:00.000 | I went for the first time to an acupuncturist.

01:42:02.880 | I know there are varying thoughts and opinions out there

01:42:05.760 | about acupuncture.

01:42:06.880 | I can't say that I benefited so much from the acupuncture.

01:42:11.860 | There are now quality peer-reviewed studies

01:42:14.820 | published in Neuron, cell press journal, excellent journal,

01:42:17.400 | showing that acupuncture can stimulate

01:42:20.280 | some anti-inflammatory compounds

01:42:22.580 | depending on where the acupuncture is done.

01:42:24.080 | This is a really good study.

01:42:25.340 | It came out last year.

01:42:26.300 | I talked about this on Instagram.

01:42:27.460 | I may talk about it again.

01:42:28.700 | As well as certain acupuncture sites

01:42:30.900 | that increase inflammation.

01:42:32.580 | So you can get different types of effects.

01:42:36.480 | You can't just say acupuncture is great across the board.

01:42:39.460 | And I'm assuming that the acupuncturists know

01:42:41.880 | which sites are good for increasing inflammation,

01:42:43.760 | which ones are good for decreasing inflammation.

01:42:46.640 | However, this acupuncturist that I went to

01:42:50.400 | gave me these red pills.

01:42:52.040 | He said, "These are minerals for sleep."

01:42:53.800 | And it was remarkable.

01:42:54.660 | I took the red pills.

01:42:56.240 | Isn't that a thing now?

01:42:57.280 | Take the red pill.

01:42:58.100 | I don't know what that means because I'm not tuned in.

01:43:00.760 | But these red pills look like little M&Ms.

01:43:03.360 | I took a couple of them on his suggestion.

01:43:05.440 | And I fell deeply asleep and four hours later

01:43:07.960 | woke up feeling incredibly rested,

01:43:09.920 | more rested than I had ever felt in my entire life.

01:43:12.000 | And I never required more than four hours sleep.

01:43:13.940 | Unfortunately, acupuncturist moved away.

01:43:16.240 | I never figured out what was in those red pills.

01:43:18.560 | I didn't get a chance to do the mass spectroscopy.

01:43:20.880 | And I still wonder, he said they were minerals.

01:43:24.000 | So somebody out there knows what these red pills are

01:43:27.360 | and what this compound is.

01:43:28.600 | And it was incredible.

01:43:30.920 | And I would love to know what those are.

01:43:33.640 | So if you know, please don't go taking red pills at random

01:43:37.440 | to try and recreate this non-experiment experience of mine.

01:43:41.880 | But please do contact me if you find out

01:43:44.940 | or if you're an acupuncturist

01:43:46.040 | and you know what these mysterious red pills were

01:43:48.560 | because they were pretty awesome.

01:43:51.760 | Once again, I've thrown a tremendous amount

01:43:53.520 | of information at you.

01:43:55.640 | I hope you will figure out your temperature minimum

01:43:58.180 | and start working with that to access the sleep

01:44:02.200 | and wakeful cycles that you want to access.

01:44:04.820 | I hope that you'll explore NSDR.

01:44:07.420 | You might want to explore supplementation

01:44:10.580 | if that's your thing.

01:44:11.900 | You have now access to a lot of mechanism

01:44:14.920 | about sleep and wakefulness.

01:44:16.640 | But in keeping with the theme of this podcast

01:44:18.580 | where we stay on topic for an entire month

01:44:21.220 | or even slightly more,

01:44:22.520 | we are not done with sleep and wakefulness.

01:44:24.920 | I know this is very different

01:44:26.720 | than the typical podcast format

01:44:28.240 | where one week it's how to become superhuman

01:44:31.500 | and the next week it's how to, you know,

01:44:34.700 | develop growth mindset.

01:44:35.840 | It's kind of all over the place with episode to episode.

01:44:38.080 | We are staying on track because I really believe

01:44:40.900 | that as we drill deeper and deeper into these mechanisms

01:44:43.720 | and you start hearing some of the same themes

01:44:45.600 | again and again,

01:44:46.840 | you're going to start to develop an intuition

01:44:49.360 | and an understanding of how these systems work in you

01:44:51.700 | and your particular life circumstances.

01:44:53.760 | And my goal is really to eventually become obsolete.

01:44:56.800 | It's what my graduate advisor used to call

01:44:58.620 | the hit by a bus principle.

01:45:00.800 | She had a somewhat morbid sense of humor

01:45:03.620 | and it used to be, well, if I get hit by a bus tomorrow,

01:45:05.620 | what are you going to do without me blabbing at you here?

01:45:09.200 | So I don't want to get hit by a bus.

01:45:11.400 | I plan on living a very long time

01:45:13.000 | if I have anything to say about it,

01:45:14.840 | but were I to get hit by a bus tomorrow,

01:45:17.640 | what would you do for your sleep and wakefulness, right?

01:45:19.920 | You could put a comment on YouTube, which I hope you'll do,

01:45:22.440 | but if I were hit by a bus and killed,

01:45:24.080 | then I wouldn't be able to answer your question.

01:45:26.800 | So know your temperature minimum.

01:45:29.720 | Understand light in the early part of the day is valuable.

01:45:32.840 | Light when you want to be awake,

01:45:34.000 | provided it's not so bright, it's damaging.

01:45:35.640 | It's great for you whether or not it comes from screens

01:45:37.340 | or sunlight, but sunlight's better.

01:45:39.340 | Avoid light in the four to six hours

01:45:42.200 | before your temperature minimum

01:45:43.560 | or else you're going to delay your clock

01:45:45.000 | unless you're traveling and that's what you want to do, okay?

01:45:48.600 | Use temperature, increase temperature to shift your clock.

01:45:51.980 | Decrease temperature to delay your clock, okay?

01:45:56.160 | Map out your temperature and understand it.

01:45:58.120 | You don't have to know degree by degree across the day.

01:46:00.960 | Know your minimum, know your maximum temperature

01:46:03.040 | in your 24-hour cycle

01:46:04.200 | and you will feel great power through that

01:46:07.120 | because then you'll know also about these ultradian cycles,

01:46:10.600 | these 90-minute cycles within which you can do focused work.

01:46:13.360 | Don't expect the focus to come early.

01:46:15.000 | Expect the focus to come in the middle

01:46:16.120 | and then kind of taper off.

01:46:18.120 | Talked a little bit about kids,

01:46:19.240 | a little bit about elderly, about parenting.

01:46:21.100 | We are going to continue.

01:46:22.160 | There's going to be more, but now shift workers, travelers,

01:46:25.680 | people that are jet-lacking themselves at home,

01:46:27.760 | you now have levers in place.

01:46:30.580 | Information can be powerful,

01:46:31.980 | but you have to implement it in ways,

01:46:34.360 | obviously safe ways and reasonable ways,

01:46:36.460 | but implementing this knowledge

01:46:38.460 | in the ways that you trust are safe and reasonable for you

01:46:41.320 | is going to be the way that you can develop

01:46:43.420 | a bit of a laboratory about yourself.

01:46:45.560 | I loathe the term biohacking.

01:46:47.740 | Sorry, biohackers.

01:46:49.080 | I don't believe in hacking anything.

01:46:50.660 | I believe in understanding mechanism

01:46:52.240 | and applying the principles of mechanism

01:46:54.380 | for which there are large bodies of quality peer-reviewed data

01:46:58.320 | and even a whole center of mass around

01:47:00.800 | certain biological principles like the effects of light

01:47:03.320 | and temperature minimums that will allow you

01:47:06.040 | to shift your biology in the ways that you want it to go,

01:47:08.440 | that will allow you to shift your psychology

01:47:10.420 | in the ways you want it to go.

01:47:12.520 | Next podcast episode,

01:47:14.560 | we are going to talk more about a few things.

01:47:17.820 | First of all, we're going to answer more of your questions

01:47:20.120 | 'cause during office hours,

01:47:21.240 | I didn't get to all your questions

01:47:22.480 | from the previous episode.

01:47:24.600 | So I do read the comments and we're paying attention

01:47:27.720 | to figuring out the most common questions.

01:47:29.680 | We are going to get to some of the harder topics.

01:47:31.360 | Someone came at me.

01:47:32.380 | It's always fun when somebody does this and they say,

01:47:33.840 | "Well, these are just the kind of

01:47:35.680 | "basal low-level questions.

01:47:36.900 | "What about the big stuff?

01:47:37.940 | "What about dreaming and lucid dreaming and consciousness?"

01:47:40.560 | Look, I'll talk about that stuff.

01:47:42.420 | And I'm planning to do that,

01:47:44.160 | some of which in the next episode

01:47:45.360 | and the following episode, maybe even.

01:47:47.340 | But I want to give you data.

01:47:49.880 | I want to give you things that are supported by data.

01:47:52.320 | So I will try to speculate as little as possible

01:47:56.680 | because this is a podcast about science

01:47:59.040 | and science-based tools for everyday life.

01:48:01.160 | This is not about me speculating.

01:48:03.740 | Many people have speculated

01:48:04.840 | about the role of sleep, dreaming, and consciousness.

01:48:06.800 | Fascinating topics and a rather circular argument, frankly.

01:48:11.160 | It's been going on for centuries.

01:48:12.800 | Someday we'll get there.

01:48:14.080 | Right now, we're concentrating

01:48:15.300 | on these deep biological mechanisms

01:48:17.020 | that make you who you are

01:48:18.400 | and allow you to feel certain ways, good or bad,

01:48:21.460 | allow you to function physically in certain ways,

01:48:25.040 | good or bad, and give you more of a sense of control.

01:48:27.700 | That's my goal here.

01:48:29.200 | Many people have quite graciously asked

01:48:31.220 | how they can help support the podcast.

01:48:33.800 | First of all, thank you.

01:48:35.000 | We appreciate the question.

01:48:36.780 | You can support the podcast

01:48:38.360 | by subscribing to the podcast on YouTube,

01:48:41.620 | as well as subscribing on Apple or Spotify.

01:48:45.040 | And you can also leave us comments

01:48:47.280 | and feedback on YouTube and at Apple.

01:48:50.320 | That really helps.

01:48:51.480 | We would hope the feedback would be positive,

01:48:53.300 | but nonetheless, leave us feedback, ask questions.

01:48:56.140 | We will use those questions

01:48:57.480 | to create future content for the podcast.

01:49:00.280 | As well, if you can recommend the podcast

01:49:02.120 | to friends and family and other people

01:49:03.880 | that you think might find the information of use,

01:49:05.780 | that's terrific.

01:49:07.020 | And check out our sponsors

01:49:08.420 | that we mentioned at the beginning.

01:49:10.040 | That's a really great way to help support us

01:49:12.500 | and our ability to bring you this information.

01:49:15.020 | Along those lines, a lot of people have asked me

01:49:17.720 | about supplements and supplement companies.

01:49:21.480 | So up until now, I've been reluctant

01:49:25.380 | to recommend specific supplement brands.

01:49:27.760 | The supplement industry is kind of a Wild West

01:49:30.980 | of different brands, different levels of quality

01:49:33.600 | and stringency.

01:49:35.280 | It can be very complicated.

01:49:37.080 | And what's on the bottle is not always what you're getting.

01:49:40.040 | The quality of what you're getting

01:49:41.400 | varies from company to company

01:49:42.900 | and even from substance to substance, batch to batch.

01:49:45.980 | So I'm pleased to say that I'm partnering with Thorne.

01:49:49.980 | Thorne, spelled T-H-O-R-N-E,

01:49:53.140 | is a supplement company that works with the Mayo Clinic

01:49:56.820 | and with pretty much all the major sports team organizations

01:50:00.140 | and that I know to have the highest levels of stringency

01:50:03.660 | in terms of what's in the bottle,

01:50:05.920 | matches what's listed on the bottle,

01:50:08.680 | and in terms of the quality

01:50:10.020 | of what they put in those supplements.

01:50:12.180 | So while I mentioned earlier

01:50:14.460 | that supplements aren't for everybody,

01:50:16.180 | if you're interested in trying some of these supplements,

01:50:18.340 | you might want to check out Thorne.

01:50:20.140 | If you want to do that,

01:50:20.980 | you can go to thorne.com/u/huberman.

01:50:25.980 | So it's T-H-O-R-N-E.com,

01:50:31.740 | C-O-M/u/huberman.

01:50:36.020 | And if you do that, they'll give you 20% off

01:50:38.720 | any of the supplements

01:50:39.740 | that you happen to purchase from Thorne.

01:50:42.040 | Thanks so much for your time and attention.

01:50:43.660 | I really appreciate it.

01:50:45.020 | See you next time on the Huberman Lab Podcast.

01:50:47.820 | And as always, thanks for your interest in science.

01:50:50.600 | (upbeat music)

01:50:53.180 | (upbeat music)

How to Defeat Jetlag, Shift Work & Sleeplessness

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