How to Defeat Jet Lag, Shift Work & Sleeplessness

0:00 - Welcome to the Huberman Lab Podcast

0:02 where we discuss science,

0:03 and science-based tools for everyday life.

0:06 [bright music]

0:09 - I'm Andrew Huberman,

0:10 and I'm a professor of neurobiology and ophthalmology,

0:13 at Stanford School of Medicine.

0:16 This podcast is separate

0:17 from my teaching and research roles at Stanford.

0:19 It is however, part of my desire

0:21 to bring you zero cost to consumer information about science

0:24 and science-related tools to the general public.

0:27 Along those lines,

0:28 I want to thank today's sponsors of the podcast.

0:31 The first sponsor is Athletic Greens.

0:33 Athletic Greens is a product

0:34 that I've been using since 2012,

0:37 long before I launched this podcast.

0:38 So I'm delighted that they're sponsoring the podcast.

0:41 Athletic Greens is an all-in-one

0:43 vitamin, mineral probiotic supplement.

0:46 It's a greens drink that you mix with water,

0:49 I add lemon juice to mine because I like the way it tastes

0:52 and it gets you all the vitamins and minerals you need

0:55 as well as probiotics, and probiotics are important to me

0:59 because there are a lot of data now showing that gut health

1:02 is important for the gut brain access,

1:05 things like mood, immunity, etc.

1:08 If you want to try Athletic Greens,

1:10 you can go to athleticgreens.com/huberman

1:13 and if you do that, they'll send you a year supply

1:16 of liquid vitamin D3 and K2.

1:19 Vitamin D3, as many of you probably already know,

1:22 it has been shown to be important

1:24 for various aspects of immune system function,

1:26 as well as other biological pathways,

1:29 metabolic function, etc.

1:31 So once again, if you want to try Athletic Greens,

1:33 you go to athleticgreens.com/huberman

1:36 and they will send you a year supply of the D3 K2.

1:40 This podcast is also brought to us by Headspace.

1:43 Headspace is a meditation app that makes meditation easy.

1:47 I've been meditating on and off

1:49 since I was in my teens with more off than on,

1:53 mainly because meditation can be hard to stick to.

1:55 Some people are very good

1:56 at maintaining a meditation practice,

1:59 others not so much, I'm in the latter category.

2:01 However, I find that

2:02 when I have something to guide my meditation

2:05 such as Headspace, it makes it much easier

2:07 for me to be consistent about my meditation practice.

2:10 There is now tons of data out there

2:13 in quality peer review journals,

2:15 showing that meditative states can facilitate

2:18 cognition, recovery of mental function,

2:21 recovery of physical ability, etc.

2:24 So there are a lot of reasons

2:25 to take up a meditation practice.

2:26 Headspace and the Headspace app makes it easy

2:29 to learn and maintain a meditation practice.

2:32 If you want to try Headspace,

2:34 you can go to headspace.com/specialoffer.

2:38 And if you do that, they will let you try Headspace

2:41 for an entire month for free.

2:42 So zero risk there, that's headspace.com/specialoffer

2:46 to try Headspace, the meditation app,

2:48 for one month for free.

2:50 Today's podcast episode is about sleep and wakefulness.

2:54 We are going to discuss jet lag, shift work,

2:59 babies, kids and the elderly,

3:01 and we are going to discuss protocols

3:03 that are backed by science.

3:05 That means quality peer reviewed papers

3:07 published in excellent journals

3:10 that can support particular tools

3:12 that you can use to combat things like jet lag,

3:15 offset some of the negative effects of shift work

3:17 and make life easier for the new parent

3:21 as well as for the newborn child, the adolescent,

3:24 anyone that wants to sleep better,

3:27 feel better when they're awake, etc.

3:30 If you've listened to the previous

3:31 three episodes of the Huberman Lab Podcast,

3:34 we've been exploring these themes

3:36 of wakefulness and sleepiness,

3:38 how to fall asleep, how to stay asleep.

3:41 And we've been discussing parameters like light,

3:43 exercise, temperature, etc.

3:47 If you've had a chance to listen to those episodes, great.

3:50 Today's discussion will be even more digestible for you.

3:55 If you haven't, that's okay.

3:57 I will provide a little bit of background here or there

3:59 so that it's not necessary

4:01 that you have listened to those previous episodes.

4:03 But if you get a chance to listen to them,

4:06 please do it,

4:07 I think it will help you digest the information better.

4:10 Let's just take a step back for a moment

4:12 and remind everybody what we're talking about.

4:15 We're talking about an endogenous, meaning within us,

4:19 rhythm that we call the circadian rhythm.

4:21 The circadian rhythm is a 24 hour rhythm

4:25 in all sorts of functions.

4:28 The most prominent one is a rhythm

4:30 in our feelings of wakefulness and sleepiness.

4:34 So believe it or not,

4:35 the experiment has been done throughout history,

4:38 not often, but it's been done

4:39 where people would go down into a cave

4:42 and will exist in constant darkness for some period of time.

4:45 There are also cases

4:46 where people have been in constant light

4:47 for some period of time.

4:49 But because people can close their eyes,

4:51 it's actually easier to do the experiment

4:53 where you're in constant darkness

4:54 to address the question of what is the endogenous,

4:57 meaning, the internal rhythm that we all have.

4:59 And it turns out we all have this rhythm of about 24 hours,

5:03 although it's not exactly 24 hours.

5:05 Meaning, every 24 hours your body temperature

5:10 goes from low to high and back down to low again.

5:13 And it takes 24 hours for that to repeat.

5:15 Not 18, not six, 24 plus or minus a couple hours.

5:20 You also have a rhythm in sleepiness and wakefulness

5:23 that correlates with that.

5:24 We tend to be sleepy as our temperature is falling,

5:28 getting lower, and we tend to be more awake or waking

5:33 when our temperature is increasing.

5:35 This is a biological fact.

5:37 It is right down to our DNA.

5:39 We actually have genes in every single one of our cells

5:42 that ensure that every cell is on this 24 hour-ish rhythm,

5:46 close to 24 hours.

5:49 We have a clock over the roof of our mouth,

5:52 a group of neurons called the suprachiasmatic nucleus.

5:56 That clock generates a 24 hour rhythm.

5:59 And that clock is in-trained, meaning it is matched,

6:02 to the external light-dark cycle,

6:04 which is no surprise, 24 hours.

6:08 Spinning of the earth takes 24 hours.

6:10 So, our cells, our organs,

6:15 our wakefulness, our temperature,

6:17 but also our metabolism, our immune system, our mood,

6:21 all of that is tethered to the outside light-dark cycle.

6:25 And if we are living our life in a perfect way,

6:29 where we wake up in the morning,

6:31 and we view sunlight as it crosses the horizon,

6:34 and then by evening, we catch a little sunlight

6:38 and then at night we're in complete darkness,

6:41 we will be more or less perfectly matched

6:43 to the external or ambient light-dark cycle.

6:46 Very few of us do that

6:48 because of these things that we call artificial lights,

6:51 and this other thing that we call life demands.

6:55 So today we're going to talk about

6:57 when we get pulled away from that rhythm.

7:00 Now you may immediately be thinking,

7:03 well, I've heard there are night owls

7:05 and there are mornings larks, they're sometimes called

7:07 and their genetic polymorphisms,

7:09 that's just a fancy name for

7:11 genetic variations that make some people want to wake up early

7:13 and other people want to stay up late

7:14 and teens want to sleep in more.

7:16 Sure, that's all true.

7:18 That's all true regardless of what names we give those.

7:20 However, there's no escaping the fact

7:23 that human beings are a diurnal species.

7:26 We were designed, literally,

7:28 our cells and the circuits of our body

7:30 were constructed to be awake during the daytime

7:34 and asleep at night.

7:35 How do I know that?

7:36 Well, I wasn't consulted at the design phase,

7:39 but I'm certain of that because many studies have shown

7:43 that when we deviate too far from a diurnal schedule

7:47 and we try and become nocturnal, we can pull it off,

7:50 but serious health effects, both mental and physical,

7:53 start to arise.

7:55 I'm not going to spend much of today

7:57 talking about all the negative effects of jet lag

7:59 I'll talk a little bit about it,

8:00 or the negative effects of shift work,

8:02 or trying to scare you

8:04 by telling you about the quite valid data

8:06 around depression, amnesia,

8:11 dementia, all the terrible things that happen

8:13 when you're not sleeping well,

8:15 rather I'd like to focus on what you can do

8:16 and arm you with tools.

8:18 So let's talk about that perfect schedule for a moment.

8:21 And then let's talk about jet lag

8:23 and what jet lag really represents

8:26 and how to push back on jet lag, shift your clock faster,

8:30 and escape some of the severe bad things

8:33 that can happen with jet lag.

8:34 Including just feeling miserable

8:36 when you're traveling for work or vacation.

8:38 So what is the perfect day?

8:41 What does that look like from our circadian

8:43 sleep-wakefulness standpoint?

8:45 I'm about to summarize what I've said in

8:47 the three previous podcast episodes,

8:50 as well as now countless Instagram posts.

8:55 Here's the deal.

8:56 You basically want to get as much light, ideally sunlight,

9:02 but as much light into your eyes

9:05 during the period of each 24 hour cycle

9:07 when you want to be awake, when you want to be alert.

9:10 And you want to get as little light into your eyes

9:15 at the times of that 24 hour cycle

9:17 when you want to be asleep or drowsy and falling asleep.

9:22 How much is enough?

9:23 Well, you don't want to go so high

9:25 with the light exposure that you damage your eyes

9:27 because as many of you have heard me say before,

9:30 the eyes are actually two pieces of your brain,

9:32 your central nervous system

9:33 that were extruded out of your skull.

9:35 And as pieces of the central nervous system, aka your brain,

9:38 they will not regenerate.

9:40 At least right now, the technologies don't exist

9:42 to regenerate those neurons in humans

9:43 you do not want to damage them.

9:45 So what is too bright?

9:46 Well, when it's painful to look at.

9:49 When you have to blink or close your eyes

9:50 in order to bear it.

9:51 So please don't look at very bright lights,

9:54 so painful that they're likely going to damage your eyes.

9:59 However, if you get up in the morning,

10:02 and it's still dark out and you want to be awake,

10:06 you would be wise to turn on artificial lights,

10:09 in particular, overhead lights

10:10 for reasons I've discussed previously.

10:12 But those overhead lights will

10:13 optimally trigger the neurons,

10:14 these melanopsin cells in the retina

10:17 that will activate your circadian clock.

10:20 When the sun comes out, even if there's cloud cover,

10:23 the sun does come out every day

10:26 regardless of where you live, unless you live in a cave.

10:29 People have said to me,

10:30 well, I live in an area where I can't really see the sun.

10:32 Well, the sun is there,

10:35 it might be hiding behind clouds,

10:37 unless it's very very dark where you live

10:39 like Scandinavia in the depths of winter

10:41 in which case you might want some artificial light.

10:44 Get some sunlight in your eyes when you can.

10:47 Here's the deal with sunlight and artificial light

10:49 that I have not discussed previously.

10:53 A lot of photon energy,

10:56 a high amount of lux, L-U-X, comes through even cloud cover.

11:00 A good number to shoot for as a rule of thumb,

11:03 is to try and get exposure

11:04 to at least 100,000 lux before 9:00 AM.

11:11 10:00 AM maybe, but before 9:00 AM

11:14 assuming you're waking up sometime between five and 8:00 AM.

11:19 Okay, so get 100,000 lux.

11:21 Now you do not, I want to repeat,

11:23 you do not want to stare at a 200,000 lux

11:26 or a 100,000 lux light.

11:28 It's very, very bright.

11:30 The mechanism of circadian clock setting

11:34 and this is very important,

11:35 the mechanism of circadian clock setting

11:37 involves these neurons in your eye

11:40 that send electrical signals

11:41 to this clock above the roof of your mouth

11:44 and that system sums, meaning it adds photons,

11:47 it's a very slow system.

11:49 So let's say that I wake up

11:51 and I look at my computer screen briefly or my phone screen.

11:55 That's probably 500 to 1,000 lux.

11:57 If I were to look at that for a full minute,

12:00 I would get that photon energy

12:02 transferred into electrical energy of neurons

12:04 and it would be communicated to my circadian clock.

12:06 However, the signal that it's morning

12:08 will not have registered with the circadian clock

12:12 unless I looked at that for a hundred minutes or more,

12:17 so 100,000.

12:17 Now the problem is if you wake up at eight o'clock,

12:20 you're not going to get enough light from artificial light

12:23 before you reach what's called the circadian dead zone.

12:26 So you have this opportunity before 9:00 AM, maybe 10:00 AM

12:29 to capture enough photons,

12:32 and you have to do it with your eyes.

12:34 I've discussed why that's important

12:36 in previous episodes of the podcast,

12:38 we have to do it with your eyes.

12:39 There is no extra ocular photo reception.

12:41 This is not about vitamin D in your skin.

12:44 This is about setting your circadian clock

12:46 which is paramount for mental and physical health.

12:48 So here we're talking about trying to get that

12:50 at least 100,000 photons but not all at once,

12:52 but you got to get them before 9:00 AM-ish, maybe 10:00 AM.

12:56 So what do you do?

12:57 You go outside.

12:58 If you want to get nerdy about this quantitative,

13:01 you could download a free app like Light Meter

13:03 and take a look around your house with Light Meter

13:06 and you'll notice that even bright overhead lights

13:08 are only emitting about 4,000 or 5,000 lux.

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

13:15 with eyes open in order to set your circadian clock

13:17 and tell your brain and body that it's morning.

13:21 Going outside even on a cloudy day

13:24 could be 7,000, 10,000 lux.

13:26 It's really remarkable how bright it is,

13:29 meaning how much photon energy is coming through.

13:31 So try and get 100,000 lux before that 9:00 AM.

13:34 Now, if you can't do that

13:35 because you live in an area of the world

13:37 where it's just not bright enough.

13:40 Some people have sent me pictures from Northern England.

13:43 It's just not bright enough in winter.

13:45 Then sure, you can resort to using artificial lights

13:49 in order to get enough photons.

13:52 And I'm putting out this 100,000 lux number as a target

13:55 to get each day before 9:00 AM.

13:59 You can in theory, get it all from artificial lights,

14:01 but there are some special qualities about sunlight

14:03 that make sunlight the better stimulus.

14:05 First of all, it's free if it's available outside.

14:09 There is a number of different...

14:12 There are, excuse me, a number of different technologies

14:14 kind of like this one like a light pad

14:16 that this one says it's a 930 lux.

14:19 I'm covering this up 'cause I'm not trying to promote

14:20 any specific products.

14:21 I actually bought this just with my own money on Amazon,

14:24 they're not a sponsor.

14:26 And it lets you toggle the brightness,

14:27 I think by holding this on, holding down this button,

14:30 you can make it dimmer or brighter.

14:31 There's about 1,000 lux, it seems really bright,

14:33 but a cloudy day outside

14:35 will have five times more photon energy coming through.

14:39 So some people set these lights or ring lights

14:41 that they use for selfies and that kind of thing

14:43 near their coffee or workstation first thing in the morning

14:46 but you really want to get sunlight, okay?

14:48 So those things are kind of nice because they'll travel

14:50 and we're going to talk about jet lag.

14:52 But I can't emphasize this enough

14:55 that light has to be captured and summed

14:57 before you enter the circadian dead zone

14:59 which is the middle of the day.

15:01 This is again, trying to achieve kind of perfect schedule.

15:05 Then I've recommended, based on scientific literature,

15:09 that you look at sunlight sometime around

15:12 the time when the sun is setting

15:13 and the reason for that of course

15:15 is because it adjusts down the sensitivity of your eyes

15:19 because here's the diabolical thing.

15:21 While we need a lot of photon energy early in the day

15:24 to wake up our system and set our circadian clock,

15:27 and prepare us for a good night's sleep

15:28 14 to 16 hours later,

15:30 it takes very little photon energy

15:33 to reset and shift our clock after 8:00 PM.

15:37 And that's why you want to, as much as you safely can,

15:39 avoid bright light and even not so bright light

15:44 between the hours of 10 or 11:00 PM and 4:00 AM.

15:48 A number of people have asked me some questions about this.

15:51 And the last episode I went into red lights,

15:53 I went ahead and discussed blue blockers,

15:55 all that kind of stuff, so I'm not going to repeat all that.

15:57 But here's the thing, if you see afternoon light,

16:01 you're going to adjust down the sensitivity of your eyes

16:04 so that you have a little bit more wiggle room,

16:08 a little bit more leeway

16:09 to view lights from screens and overhead lights even

16:13 late at night without disrupting your circadian clock.

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

16:19 where you need a lot of light early in the day

16:23 and you need to avoid bright lights later in the day.

16:26 I've mentioned studies on here,

16:27 a number of you have asked about getting the references.

16:30 We are in the process of trying to get a webpage

16:32 going with full links.

16:33 There's some copyright issues that we have to deal with.

16:35 But wherever possible, I'll try and reference these studies

16:38 and when people ask I'll generally put them

16:40 in the response to their comments on YouTube or Instagram.

16:45 There have been two studies

16:47 done from University of Colorado,

16:48 both published in Current Biology.

16:50 You can easily find these online

16:52 by just googling the words, Current Biology,

16:55 camping and reset circadian clocks,

16:58 that have shown that two days of waking up with the sun

17:02 and avoiding light at night,

17:04 they actually took graduate students camping,

17:05 what a cool experiment to be a part of,

17:08 reset the melatonin and cortisol rhythms

17:10 for these people that had otherwise

17:12 drifted quite far from their natural rhythms.

17:16 There're other things that you can do to shift your clock

17:19 and to reinforce your clock.

17:20 Like exercising more or less the same time,

17:22 eating more or less the same time, etc.

17:24 That's not what today's episode is about.

17:25 So I just described perfect schedule.

17:27 Get at least 100,000 lux of light exposure to the eyes

17:30 not all at once, but summing across the morning.

17:33 Again you know when it's too much

17:35 because it's painful to look at,

17:37 so that's obviously something to avoid.

17:40 But then once the middle of the day,

17:42 let's say, you're waking up at 10 or 11

17:43 you go outside the sun's overhead, forget it,

17:45 you're not going to shift your clock, you're just not.

17:48 It doesn't work that way.

17:50 In the evening, you see the evening light

17:53 and you want to get that light

17:55 to adjust down your retinal sensitivity

17:57 to afford you a bit of a buffer so that late at night,

18:00 if you happen to look at screens

18:01 or go to the bathroom in the middle of the night,

18:03 it's not going to shift your clock

18:05 because it takes probably only about

18:07 1,000 to 1500 lux of light energy

18:11 to shift your clock in the middle of the night.

18:13 So let's talk about shifting clocks

18:14 because for the jet lagged person,

18:17 this ability to shift the clock

18:19 with light, temperature, exercise, and food

18:22 is vitally important

18:23 for getting onto the new local schedule.

18:27 And there's so much out there about jet lag today.

18:28 I'm going to dial it down to one very specific parameter

18:32 that all of you can figure out

18:34 without any technology or devices

18:37 and can apply for when you travel for work or pleasure,

18:42 or anytime you're jet lagged,

18:43 and I want to absolutely emphasize

18:46 that you don't have to travel to get jet lagged.

18:48 Many of you are jet lagged.

18:50 You're jet lagged because

18:51 you're looking at your phone in the middle of the night,

18:53 you're jet lagged 'cause you're waking up

18:54 at different times a day, you're jet lagged because

18:57 your exercise is on a kind of chaotic regime,

19:01 some days at this time, some days at that time.

19:03 And if that works for you, great.

19:05 I want to be really clear that

19:07 a number of people always say, well, I know so and so that

19:10 you know only needed four hours of sleep and,

19:12 or they're just fine,

19:14 they traveled to Europe and they're just fine.

19:16 There's a lot of individual variability.

19:17 And we're going to talk about

19:18 the origins of some of that variability.

19:20 I mean, I know people that can eat anything

19:23 and somehow seem to maintain great lipid profiles

19:26 and you know, body weight and fitness ability.

19:31 And I know some people that they eat one cracker

19:33 and they sort of dissolve into a puddle of

19:36 kind of tears, right, because they think that that's going to

19:39 throw them off and maybe it does, I don't know.

19:41 There's a tremendous amount of variability out there.

19:44 So, this is really about optimal and what's possible.

19:50 And you have to ask,

19:51 I can just say from personal experience,

19:53 I suffer terribly from jet lag,

19:56 traveling in certain directions but not others.

19:58 Some people don't have trouble with jet lag.

20:00 Many people will travel to a new location,

20:03 they feel great for the first day and night

20:05 and then they crash and they have trouble sleeping.

20:08 Or they travel back and they have a terrible time

20:10 getting back onto a normal schedule.

20:12 And some of this varies with age

20:14 and some of it varies with genetics

20:16 and there is no simple pill or anything that you can take

20:20 to just get rid of jet lag.

20:22 It doesn't work that way.

20:23 If it worked that way, I would tell you.

20:26 But there are some simple things that you can do.

20:28 I'm going to arm you with the knowledge

20:29 of what jet lag is and how it works.

20:32 And contrary to what many people out there say and believe,

20:36 I know that understanding mechanism

20:38 affords you more flexibility.

20:41 Why understand mechanism as just opposed

20:43 to me just writing up a PDF

20:44 and giving you a list of things to do?

20:45 Well, what happens when you can't do those things

20:48 in exactly the way they're written down.

20:50 When you understand mechanism,

20:52 you understand how to control the machine

20:55 that is your biological system, your nervous system.

20:58 So a little bit of understanding about mechanism

21:00 goes a really long way.

21:02 So that's where we're headed.

21:03 Let's talk about what jet lag is.

21:05 Okay well, I promised that I wouldn't get too dark

21:08 with all the terrible things that can happen with jet lag,

21:11 but I'm about to get dark.

21:14 There are quality peer reviewed papers

21:17 showing that jet lag will shorten your life.

21:20 It will kill you earlier.

21:23 I guess it means you'll die earlier.

21:25 It doesn't actually kill you necessarily.

21:27 Although there are many cases where tourists

21:30 end up stepping in front of buses,

21:32 especially in countries where the cars and buses

21:35 drive on the opposite side of the street

21:36 that they're used to,

21:38 who are jet lagged and lose their life that way.

21:40 Jet lag is a serious thing.

21:41 Sure we have a family story about this.

21:43 When I was growing up,

21:44 I had a family member travel overseas for work

21:47 and take a sleeping pill, I won't name the sleeping pill,

21:51 though at the end I'm going to talk about sleeping pills,

21:53 and had a case of total amnesia for a week.

21:57 That's not entirely uncommon.

21:59 If you've ever been really jet lagged and fallen asleep,

22:02 doesn't even have to be in the middle of the day, woken up,

22:04 you might not know where you are.

22:06 And that's because time and space

22:07 are really linked in the brain,

22:09 wasn't designed to be transported four, five six hours

22:12 into a new time zone, it just wasn't.

22:15 Our brain and the biological mechanisms

22:17 that govern circadian timing

22:19 were designed to be shifted by a couple hours,

22:22 not necessarily six or nine or 12 hours.

22:25 So you can really mess yourself up.

22:26 I've had that experience,

22:27 I usually experience it as fluctuations in mood.

22:30 I flew 12 hours out of phase,

22:33 to Abu Dhabi once, to give a talk at NYU Abu Dhabi,

22:36 and it was a mess.

22:37 I actually was getting vertigo.

22:41 I wasn't hallucinating but I was really out of it.

22:44 And my mood was just all over the place.

22:47 And it was very bizarre.

22:49 Jet lag, even if you don't experience it

22:51 as mood shifts or amnesia, it can shorten your life.

22:56 Now here's what's interesting.

22:58 Traveling westward on the globe

23:01 is always easier than traveling eastward, okay?

23:08 It's interesting because

23:10 the effects of jet lag on longevity,

23:14 have shown that traveling east

23:17 takes more years off your life than traveling west.

23:22 Now, of course, traveling 30 minutes into a new time zone

23:25 or just one time zone over, or two times zone over rather,

23:30 is far less detrimental to your biology and psychology

23:34 than a eight hour shift or a nine hour shift.

23:37 Now, here's what's interesting.

23:40 When we think about the effects of jet lag on longevity

23:44 or this idea that it can shorten our lives,

23:49 we have to ask ourselves why, why is that?

23:52 And it turns out there's a pretty simple

23:53 explanation for this.

23:55 We've talked before about the autonomic nervous system,

23:58 this set of neurons in our spinal cord and body and brain

24:01 that regulate our wakefulness and our sleepiness.

24:04 Turns out that human beings, and probably most species,

24:08 are better able to activate and stay alert

24:12 than they are to shut down their nervous system

24:15 and go to sleep on demand.

24:16 So if you really have to push,

24:18 and you really have to stay awake, you can do it,

24:20 you can stay up later.

24:22 But falling asleep earlier is harder.

24:24 And that's why traveling east

24:26 has a number of different features associated with it,

24:29 that because you're traveling east

24:31 you're trying to go to bed earlier, you know.

24:34 As a Californian, if I go to New York city,

24:37 I've got to get to bed three hours early

24:38 and wake up three hours early,

24:40 much harder than coming back to California

24:42 and just staying up a few more hours.

24:44 And this probably has roots in

24:48 evolutionary adaptation where

24:50 under conditions where we need to suddenly gather up and go

24:52 or forge for food, or fight,

24:55 or do any number of different things,

24:57 that we can push ourselves

24:58 through the release of adrenaline and epinephrin

25:00 to stay awake.

25:01 Whereas being able to slow down and deliberately fall asleep

25:04 is actually much harder to do.

25:06 So there's an asymmetry to our autonomic nervous system

25:08 that plays out in the asymmetry of jet lag.

25:13 So, if you want to read up on this,

25:15 because people have asked me about papers, you can look,

25:18 there's a paper published by Davidson and colleagues,

25:20 2006, in Current Biology that talks about

25:23 the differences in life span

25:25 for frequent eastward versus westward,

25:29 versus no travel and longevity and etc.

25:34 A number of different biological markers of longevity.

25:37 So going east is harder

25:39 because going to sleep earlier is harder,

25:41 if you're trying to do that on demand.

25:44 Many people have turned to melatonin

25:45 as a way to try and induce sleepiness.

25:48 I'm going to talk about melatonin at the end.

25:50 I've mentioned on previous podcasts,

25:52 a number of you have asked for the evidence

25:54 that melatonin is potentially detrimental

25:57 to some hormone systems, melatonin is a hormone.

26:00 And I'll discuss that at the end,

26:02 in particular, the role of melatonin

26:04 in suppressing a hormone pathway

26:06 that involves luteinizing hormone

26:08 testosterone in men and estrogen in females.

26:11 As well as a really interesting peptide called

26:13 kisspeptin, that's a cool name.

26:15 All right, well, let's think about travel and what happens.

26:19 Let's say you're not going eastward or westward

26:22 but you're going north or south.

26:24 So if you go from for instance,

26:26 Washington DC to Santiago Chile,

26:29 or you go from Tel Aviv, Israel, to Cape town, South Africa,

26:35 you're just north and south, right?

26:38 And not either direction.

26:40 You're not really moving into a different time zone,

26:42 you're not shifting.

26:43 So you will experience travel fatigue.

26:47 And turns out that jet lag has two elements,

26:48 travel fatigue and time zone jet lag.

26:52 Time zone jet lag is simply

26:56 the inability of local sunlight and local darkness

27:01 to match to your internal rhythm,

27:03 this endogenous rhythm that you have.

27:06 So before we get too complicated

27:09 and too down in the weeds about this,

27:11 I want to just throw out a couple important things.

27:14 First of all, I mentioned this earlier,

27:15 but some people suffer from jet lag a lot,

27:18 other people not so much.

27:20 Most people experience worse jet lag as they get older.

27:24 There are reasons for that because early in life,

27:26 patterns of melatonin release

27:29 are very stable and flat and very high actually in children.

27:33 It's one of the reasons why they don't undergo puberty.

27:36 Then it becomes cyclical during puberty,

27:37 meaning it comes on once every 24 hours

27:40 and turns off once every 24 hours, it cycles, cyclic.

27:44 And then as we get older, the cycles get more disrupted

27:47 and we become more vulnerable

27:49 to even small changes in schedule, etc, meal times, right?

27:53 So, jet lag gets worse as we age.

27:58 In addition, there are other things that happen with age

28:01 that people start doing less exercise,

28:04 their digestion can get worse, etc.

28:07 So some of the effects of age

28:09 might not be direct effects of getting older

28:11 but some of the things that are correlated with being older.

28:14 Like people who are willing

28:15 to have a regular exercise regime

28:17 can use that exercise regime to shift their circadian clock.

28:20 And I have a good friend, his father is in his 80s.

28:24 He's still pushing out 25, 30 push-ups each morning,

28:29 he's on the Peloton or whatever it is,

28:31 doing a lot of cycling.

28:32 So some 80-year olds are doing that, many are not,

28:35 many 30 year olds are not.

28:37 But if you have a regular exercise program,

28:40 that's going to make it easier

28:42 to shift your circadian clock for the sake of jet lag.

28:45 And it's actually a knob you can turn

28:47 and you can leverage for shifting your clock.

28:51 Before we go any further,

28:52 I want to make changing your internal rhythm really easy.

28:57 Or at least as easy

28:59 and as simple as one could possibly make it, I believe.

29:03 What I want to talk about

29:04 is perhaps one of the most important things to know

29:07 about your body and brain,

29:08 which is called your temperature minimum, okay?

29:10 Most of you know your approximate weight,

29:12 some of you might even know your blood pressure,

29:15 some of you might even know your body mass index,

29:18 some of you might know other things about your biology

29:20 that have fancy names,

29:22 but everyone should know their temperature minimum.

29:26 Your temperature minimum

29:27 doesn't require a thermometer to measure,

29:29 although you could measure it.

29:31 Your temperature minimum is the point in every 24 hour cycle

29:35 when your temperature is lowest.

29:38 Now, how do you measure that without a thermometer?

29:42 It tends to fall 90 minutes to two hours

29:44 before your average waking time.

29:47 So I want to repeat that, your temperature minimum

29:48 tends to fall 90 minutes to two hours before

29:52 your average waking time.

29:54 So let's say you're not traveling

29:56 and your typical wake up time is 5:30 AM.

29:59 Your temperature minimum is very likely 3:30 AM or 4:00 AM.

30:04 If you want, if any of you want to,

30:07 you can measure your temperature minimum.

30:09 You can get a thermometer

30:10 and you can measure your temperature every couple hours

30:11 for 24 hours, and you can find your temperature minimum.

30:14 What you're going to find is that

30:16 you have a low point, the temperature minimum,

30:18 and then your temperature will start to rise,

30:19 you'll wake up about two hours later.

30:22 Then your temperature will continue to rise

30:24 into the afternoon it will peak,

30:26 maybe a little trough, sometimes that happens,

30:28 and then it'll start declining slowly

30:33 as you approach nighttime.

30:35 There are things that will disrupt that temperature pattern.

30:38 Saunas, cold baths, intense exercise, etc.

30:42 Meals tend to have a thermogenic effect

30:44 that increases temperature slightly little blips,

30:47 but the overall cycle 24 hour cycle of temperature

30:50 has this pattern.

30:52 And last time I talked about the seminal work

30:54 of Joe Takahashi and others, who have shown that temperature

30:57 actually is the signal by which

30:59 this clock above the roof of your mouth

31:01 in-trains or collectively

31:04 pushes all the cells and tissues of our body

31:06 to be on the same schedule.

31:08 Temperature is the effector.

31:10 And once you hear that there should be an immediate,

31:13 oh, of course, because how else would you get

31:16 all these different diverse cell types

31:19 to follow one pattern, right?

31:21 A pancreatic cell does something very different

31:23 than a spleen cell or a neuron, right?

31:27 They're all doing different things at different rates.

31:30 So the temperature signal can go out

31:31 and then each one of those

31:32 can interpret the temperature signal

31:34 as one unified and consistent theme of their environment.

31:38 So temperatures vary from person to person.

31:42 Some people are 98.6, some people run a little colder, etc.

31:45 But you have a low point, and you have a high point.

31:47 Know your temperature minimum.

31:49 How are you going to figure out this temperature minimum?

31:51 The temperature minimum can be determined

31:54 by taking the last three to five wake up times.

31:58 So let's say you wake up 7:00 AM,

32:01 8:00 AM, 3:00 AM, all right it happens.

32:05 Take those, add them together, average them

32:08 by adding them up and dividing by the number of days,

32:11 that'll give you the average.

32:13 If you're one of these people that wakes up at 3:00 AM

32:15 and then goes back to sleep and sleep till 10,

32:16 your wake up time was 10:00 AM.

32:19 If you use an alarm clock,

32:20 your wake-up time is still when you get up, okay?

32:25 I know alarm clocks have been kind of demonized

32:27 but in my world

32:29 being late and missing appointments is also demonized,

32:31 so I use an alarm clock.

32:35 Many people will wake up at exactly the same time each day,

32:38 there tends to some variation for people.

32:40 Some people it's going to vary depending on life circumstances.

32:42 But average that for three to seven days or so.

32:46 Take that wake up time, you can then get an average

32:50 or sort of typical temperature minimum.

32:52 Okay, so now you know how to get your temperature minimum.

32:55 Your temperature minimum is your absolute reference point

33:01 for shifting your circadian clock.

33:03 Whether or not it's for jet lag, or shift work,

33:05 or some other purpose.

33:07 Here's the deal.

33:10 If you expose your eyes to bright light

33:14 in the four hours, maybe five or six,

33:17 but in the four hours after your temperature minimum,

33:21 your circadian clock

33:24 will shift so that you will tend to get up earlier

33:27 and go to sleep earlier in the subsequent days, okay?

33:31 So it's called a phase advance,

33:34 if you'd like to read up on this further.

33:35 You advance your clock, okay?

33:39 However, if you view bright light

33:42 in the four to six hours before your temperature minimum,

33:47 you will tend to phase delay your clock.

33:50 You will tend to wake up later and go to sleep later.

33:54 Okay, I'm going to repeat this

33:55 because there's so much confusion out there

33:56 and people talk about circadian time and all this.

33:58 Find your temperature minimum.

34:00 I tend to wake up at about 6:00 AM,

34:02 sometimes 6:30, sometimes seven.

34:04 It depends a lot on what I was doing the night before

34:06 as I'm guessing it does for you.

34:08 But that means that my temperature minimum

34:11 is probably somewhere right around 4:30 AM.

34:14 Which means that if I wake up at 4:30 AM

34:17 and I were to view bright light at 4:35 AM,

34:22 I'm going to advance my clock.

34:24 I'm going to want to go to bed earlier the subsequent night

34:28 and wake up earlier the subsequent morning.

34:31 And as I shift my wake-up time,

34:34 my temperature minimum shifts too, right?

34:37 Because each time we shift our wake-up time

34:39 our temperature minimum shifts,

34:40 assuming that wake up time

34:42 shifts more than 30 minutes or an hour, okay.

34:47 If I were to view bright light

34:48 in the four to six hours before 4:30 AM, guess what?

34:53 The next night I'm going to want to stay up later

34:55 and I'm going to want to wake up later the subsequent morning.

34:59 Your temperature minimum is a reference point

35:01 not a temperature reading.

35:03 Again, if you want to measure your temperature minimum

35:06 and figure out what it is,

35:07 98 point whatever or 96 point whatever, that's fine.

35:10 You can do that.

35:11 But that information won't help you.

35:12 What you need to know is what time

35:14 your body temperature is lowest

35:16 and understand that in the four hours or so

35:18 just after that time,

35:20 viewing light will advance your clock

35:22 to make you want to get up earlier.

35:26 And the four hours before your temperature minimum,

35:29 viewing light will make you want to stay up later.

35:33 Now, some people might be saying,

35:34 well, I wake up early and I want to stay up late

35:36 and I'm sleepy all day and I'm a mess or I feel fine.

35:39 Look, let's talk about feeling fine.

35:42 Turns out the definition of insomnia

35:45 is when you're experiencing

35:47 excessive sleepiness during the day.

35:49 Sleepiness and fatigue are different, okay?

35:52 So in the world of sleep medicine

35:54 fatigue is a physical exhaustion,

35:57 sleepiness is falling asleep.

35:59 Like falling asleep at your desk

36:01 or falling asleep during lectures,

36:03 or there seems to be something special about my lectures

36:05 that makes people want to fall asleep.

36:06 So if this cures your insomnia fantastic,

36:09 however, in all seriousness,

36:12 sleepiness during the day time

36:15 unless it's around your temperature peak

36:17 and only lasts about 90 minutes or so,

36:19 is a sign of insomnia.

36:22 It's a sign of lack of sleep.

36:26 I want to be very, very clear that

36:29 if you know your temperature minimum,

36:31 you can shift your clock using light.

36:34 You can also shift your clock by engaging in exercise

36:38 in the four hours after your temperature minimum

36:40 to wake up earlier on subsequent nights,

36:43 or exercise before then to delay your clock, okay?

36:46 So now you can start to see and understand

36:48 the logic of the system.

36:51 And we'll talk about why this works

36:53 and the underlying biology,

36:54 but understanding that temperature is the effector

36:58 and understanding that you have this low point

37:00 that reflects your most sleepy point,

37:03 essentially right before waking up,

37:05 and then temperature rises,

37:07 you can now start to shift that temperature

37:09 according to your travel needs.

37:12 Here's one way in which you might do that.

37:14 Let's say I am going to travel to Europe,

37:16 which is nine hours ahead typically, from California.

37:22 I would want to determine my temperature minimum

37:24 which for me is about 4:30 AM maybe 5:00 AM,

37:27 and I would want to start getting up

37:30 at about 5:30 AM and getting some bright light exposure,

37:36 presumably from artificial sources

37:37 because the sunlight isn't going to be out at that time.

37:41 Maybe even exercising as well,

37:42 maybe even eating a meal at that time

37:45 if that's in your practice.

37:48 You would want to start doing that

37:49 two or three days before travel.

37:53 Because, once you land in or I land in Europe,

37:59 chances are just viewing the sunrise or sunset in Europe

38:02 is not going to allow me to shift my circadian clock.

38:05 Some people say get sunlight in your eyes when you land

38:07 but that's not going to work

38:09 because one of two things is likely to happen.

38:13 With a nine hour shift like that

38:14 either I'm going to view sunlight

38:16 at a time that corresponds to the circadian dead zone,

38:19 the time in which my circadian clock can't be shifted,

38:22 or I'm going to end up viewing sunlight

38:24 at a time that corresponds to the four to six hour window

38:29 before my temperature minimum.

38:32 So it's going to shift me in exactly the opposite direction

38:35 that I want to go.

38:37 So it can be very, very challenging

38:39 for people to adjust to jet lag.

38:41 So you need to ask, am I traveling east

38:44 or am I traveling west?

38:45 Am I trying to advance my clock or delay my clock?

38:47 Remember viewing light, exercise and eating

38:51 in the four to six hours before your temperature minimum

38:54 will delay your clock.

38:55 Eating, viewing sunlight, and exercising,

38:58 you don't have to do all three

38:59 but some combination of those

39:01 in the four to six hours after your temperature minimum

39:03 will advance your clock.

39:05 And this is a powerful mechanism

39:06 by which you can shift your clock anywhere

39:08 from one to three hours per day, which is remarkable.

39:13 That means your temperature minimum is going to shift out

39:15 as much as three hours, which can make it such that you can

39:19 travel all the way to Europe

39:21 and in as long as you've prepared for a day or so

39:24 by doing what I described back home

39:27 and then doing it when you arrive,

39:30 you can potentially accomplish the entire shift within

39:33 anywhere from 24 to 36 hours.

39:36 And this is really important to emphasize

39:40 that once you arrive in your new location

39:42 and here I'm talking about traveling eastward,

39:44 California to Europe, once you arrive in your new location,

39:48 you have to keep track

39:50 of what your temperature minimum was back home

39:52 and how it's being shifted during your trip.

39:54 Now it's much easier to do than you think.

39:56 One of the unfortunate consequences

39:59 of the smartphone is that

40:02 you can't do something goofy like wearing two watches.

40:05 One watch that corresponds to the time back home

40:07 and another one that corresponds to the local time.

40:10 Typically it updates automatically based on wifi, etc.

40:15 But if you can keep track of the time back home

40:19 then you can easily shift your clock going forward.

40:22 I'm hoping this will makes sense.

40:24 I really want to emphasize

40:26 that you don't have to be precise down to the minute.

40:28 Some of you may be asking, well,

40:30 what about you've got this temperature minimum

40:32 and if I view light one minute before it

40:34 then I'm going to delay my clock and one minute after it

40:36 I'm going to advance my clock.

40:37 It doesn't quite work like that, okay.

40:40 But it's very important to understand

40:42 that light is the primary way

40:44 in which we can shift our clock.

40:46 And now you should also be able to understand

40:49 things like the circadian dead zone from about

40:51 9:30, 10:00 AM all the way until

40:56 six hours before your temperature minimum.

40:58 You're not going to shift your clock.

41:00 Nothing that you do in that time

41:01 in terms of light viewing behavior, feeding, etc,

41:04 is going to shift your clock.

41:06 And so a lot of people are landing in Europe

41:08 getting sunlight in their eyes

41:10 and throwing their clock out of whack

41:12 or not shifting their clock at all.

41:15 This brings me to the other thing that's highly recommended.

41:18 And I've mentioned this before,

41:19 but you want to eat on the local meal schedule.

41:21 If it's in your practice to fast, fast, that's fine.

41:26 But when you eat, you want to eat

41:28 within the local schedule for alertness.

41:31 Okay.

41:33 That means if you arrive and everyone's eating breakfast

41:35 and you can't stomach the idea of breakfast

41:38 in your new location 'cause your appetite isn't there.

41:40 That means the clock in your liver,

41:41 you have a clock in your liver, biological clock,

41:44 has not caught up to the new time zone.

41:48 You can force yourself to eat if you like,

41:51 or you can skip that meal.

41:53 But what you don't want to do

41:54 is stay on your home meal schedule,

41:57 waking up in the middle of the night and eating.

41:58 That is really going to throw things off

42:00 because a lot of the clocks in the periphery

42:02 like from the liver, the peripheral body,

42:04 will send information back to the brain

42:06 and then the brain is getting really conflicted signals.

42:09 So the temperature minimum is really your anchor point

42:12 for shifting your clock best.

42:14 I don't know why this information really hasn't made it

42:16 into the popular sphere, quite so much.

42:19 There's all sorts of stuff about

42:20 taking things like melatonin, using binaural beats,

42:23 a lot of kind of like more sophisticated, complicated,

42:28 and potentially problematic

42:30 ways of trying to shift the clock.

42:32 Let's talk about melatonin but first I just want to pause

42:35 and shift gears a little bit

42:38 because I talked about traveling eastward,

42:41 but we haven't talked about traveling westward.

42:44 So I want to do that now.

42:45 Let's say you're raveling from New York to California

42:47 or from Europe to California.

42:49 The challenge there tends to be,

42:52 how can you stay up late enough?

42:54 Now, some people are able to do this

42:56 because as I mentioned earlier,

42:57 the autonomic nervous system is asymmetrically wired

43:00 such that it's easier to stay up late

43:03 later than we would naturally want to

43:05 than it is to go to sleep earlier.

43:06 So let's say you land and it's 4:00 PM

43:09 and you're just dying, you're in California,

43:12 you came from Europe, it's 4:00 PM

43:13 and you really, really want to go to sleep.

43:16 That's where the use of things like caffeine, exercise,

43:19 and sunlight can shift you, right?

43:22 If it's after your temperature peak

43:24 then viewing sunlight around 6:00 PM or 8:00 PM

43:27 or artificial light, if there isn't sunlight,

43:31 will help shift you later, right?

43:33 It's going to delay your clock

43:35 and you're going to be able to stay up later.

43:38 The worst thing you can do is take a nap

43:40 that was intended to last 20 minutes or an hour.

43:43 I do this routinely and then wake up four hours later

43:46 or you wake up and it's midnight

43:48 and you can't fall back asleep.

43:49 You really want to avoid doing that.

43:52 So provided it's not excessive amounts,

43:55 stimulants like caffeine and coffee or tea

43:57 can really help you push past that afternoon barrier

44:00 and get you to sleep more like on the local schedule.

44:05 And eating on the local schedule as well.

44:09 A number of people have asked about

44:11 the use of melatonin to induce sleepiness.

44:13 All right, well let's think about what melatonin is.

44:16 Melatonin is this hormone

44:18 that's released from the pineal gland, which is this gland.

44:21 A couple of notes about the pineal,

44:23 'cause I've been getting a lot of questions about this.

44:25 I'm probably going to draw some fire for this

44:26 but I'd be happy to have a thoughtful, considerate debate,

44:31 with some peer reviewed papers in front of us.

44:34 The pineal does make this hallucinogenic molecule

44:37 they call DMT,

44:39 but in such a minuscule amounts that it is not responsible

44:42 for the hallucinations you see in sleep and dreaming.

44:45 Sorry, folks.

44:46 It's also not responsible

44:47 for the hallucinations you might see

44:48 through other approaches to DMT.

44:51 It's just not, that's not where the DMT comes from.

44:53 It's infinitesimally small amounts.

44:57 There are a lot of kind of wacky claims out there

44:59 about calcification of the pineal and fluoride

45:03 and this kind of thing.

45:05 Look, the pineal sits in an area of the brain

45:10 near the fourth ventricle,

45:12 where the skull is not terribly far away

45:16 although there's some overlap in neural tissue

45:18 and with age there's some aggregation

45:22 of some of the meninges and other things around there

45:25 that stick to the skull.

45:26 Young brains don't look like old brains

45:27 but there's no calcification of the pineal, all right?

45:30 So you can forget about calcification of the pineal

45:33 as a problem.

45:35 I don't know where that whole thing got started

45:36 but that's not an issue.

45:39 Your pineal will churn out melatonin your whole life.

45:43 Melatonin induces sleepiness.

45:45 Melatonin during development is also responsible

45:49 for timing the secretion of certain hormones

45:52 that are vitally important for puberty.

45:56 Does melatonin control the onset of puberty?

45:58 Not directly, but indirectly.

46:01 Melatonin inhibits something called

46:03 gonadotropin-releasing hormone,

46:05 which is a hormone that's released from your hypothalamus

46:07 also roughly above the roof of your mouth in your brain.

46:10 Gonadotropin-releasing hormone is really interesting

46:11 'cause it stimulates the release of another hormone

46:14 called luteinizing hormone, which in females causes

46:18 estrogen to be released within the ovaries,

46:22 it's involved in reproductive cycles,

46:24 and in males stimulates testosterone

46:27 from the sertoli cells of the testes.

46:31 Melatonin is inhibitory to GnRH,

46:34 gonadotropin-releasing hormone,

46:35 and therefore is inhibitory to LH, luteinizing hormone,

46:38 and therefore is inhibitory to testosterone and estrogen.

46:41 There's just no two ways about it.

46:45 There is immense amount of data on the fact that

46:50 high levels of melatonin in seasonally breeding animals,

46:54 takes the ovaries from nice and robust ovaries

46:57 that are capable of deploying eggs and this kind of thing

47:00 and literally shrinking them

47:02 and making these animals infertile.

47:04 These are very high levels of melatonin

47:05 in seasonal breeders in winter.

47:08 Melatonin in males of seasonal breeders

47:11 takes the testes and shrinks them.

47:13 Long ago when I was at UC, Berkeley as a master's student,

47:17 I was working on neuroendocrinology,

47:19 and we were working on

47:21 this hamster species of seasonal breeders.

47:23 And basically when days are long, which inhibits melatonin,

47:27 these little Siberian hamsters as they're called,

47:30 have testes about the size of, sort of typical table grapes,

47:34 although that's a weird way to put it.

47:37 When days get shorter and the melatonin signal gets longer

47:41 because light inhibits melatonin,

47:42 days get shorter, melatonin gets longer.

47:43 Those same hamsters would have testes

47:46 that would involute to the size of about a grain of rice.

47:49 Now this does not happen in humans in short days.

47:53 But nonetheless, the melatonin signal really does have

47:57 a ton of effects on the hormone system.

47:59 Now, does that mean that if you've been taking melatonin

48:02 you've really screwed up your hormones?

48:03 Not necessarily.

48:04 Does it mean if a kid has been taking melatonin

48:05 that's really screwing up their puberty?

48:07 Not necessarily and here's why.

48:11 Melatonin operates on a concentration level.

48:15 So in a child that's very, very small

48:19 that has high levels of melatonin,

48:21 it actually can inhibit GnRH, LH,

48:24 testosterone or estrogen depending on the sex of the child.

48:28 But as that child grows through other mechanisms,

48:30 like growth hormone release, etc,

48:32 that same amount of melatonin released from the pineal

48:34 is now diluted over a much larger body

48:36 so that the concentration actually goes way, way down, okay?

48:40 But here's the problem with supplementing melatonin.

48:43 As I mentioned in the previous episode,

48:45 concentrations of melatonin in many commercial supplements

48:48 have been shown to be anywhere from 85% to 400%

48:52 of what's listed on the bottle.

48:54 So when you take melatonin or a child takes melatonin

48:57 oftentimes they are taking super physiological

49:00 levels of melatonin,

49:01 which at least by my read, and the literature,

49:06 says that it could have dramatic effects

49:08 on timing and course of things like puberty.

49:12 So it's not so much that the journals have come out saying,

49:16 oh, taking that melatonin inhibits puberty,

49:19 it's that no single study has been done

49:21 with the super physiological levels of melatonin

49:23 that are present in a lot of these supplements

49:26 in developing children.

49:29 So melatonin is used widely for inducing sleepiness

49:33 when you want to fall asleep

49:34 in the new location that you've arrived, right?

49:37 You can't fall asleep, you take melatonin,

49:38 it helps you fall asleep.

49:40 It does not help you stay asleep.

49:42 In addition to that, melatonin has been kind of touted

49:46 as the best way to shift your circadian clock.

49:49 I'm happy to go on record saying,

49:51 look, if you need melatonin, you can work with a doctor

49:53 or somebody who really understands

49:54 circadian and sleep biology go for it, if that's your thing.

49:57 But I, as always on this podcast and elsewhere,

50:01 I have a bias toward behavioral things

50:05 that you can titrate and control

50:07 like exposure to light exercise, temperature, etc,

50:09 that have much bigger margins for safety

50:12 and certainly don't have these other endocrine effects

50:14 that we've been thinking about and talking about.

50:17 So if you want to take melatonin in the afternoon

50:20 in order to fall asleep or in the evening,

50:22 be my guest, that's up to you.

50:24 Again, you're responsible for your health, not me.

50:27 But for many people

50:29 melatonin is not going to be the best solution.

50:32 The best solution is going to be to use

50:34 light and temperature, and exercise

50:36 on either side of the temperature minimum

50:39 to shift your clock both before your trip

50:41 and when you land in your new location

50:42 and your clock starts to shift.

50:44 Okay, so now you know my opinions about melatonin,

50:47 feel free to filter them through

50:49 your own opinions and experiences with melatonin.

50:53 And now you also understand

50:55 what your temperature minimum is

50:56 and how it represents an important landmark

50:59 either side of which you can use

51:02 light, temperature, and exercise to shift your clock.

51:05 Just to remind you a little bit about temperature,

51:07 if you want to shift your clock,

51:09 typically you would do that by you can take a hot shower

51:13 and then that will have a cooling effect

51:15 after the hot shower.

51:17 And if you were to get into a cold shower

51:20 or an ice bath if you have access to one,

51:22 afterward there's going to be a thermogenic effect

51:24 of your body increasing temperature.

51:26 And if you just think about your natural rhythm back home

51:30 when everything's stable,

51:32 you have an idea a low point

51:34 in which is your temperature minimum,

51:36 and then you have a peak,

51:38 and you think about when you're doing this

51:39 hot or cold shower in that rhythm,

51:42 now you should be able to understand

51:44 how you're shifting your rhythm.

51:45 That temperature rhythm is the one that's going to move.

51:48 Give you an example.

51:49 If I were to wake up in the morning

51:51 and let's say I wake up at 6:00 AM.

51:54 My temperature I know is rising,

51:55 I've passed my temperature minimum.

51:57 If I were to get into a hot shower,

52:01 that would then lower my body temperature when I got out,

52:04 that is not normally what's happening

52:06 first thing in the morning, and therefore

52:09 my clock would very likely get phase delayed, right?

52:12 It's going to delay the increase in temperature.

52:15 Whereas if I got into a cold shower,

52:17 something I don't personally like to do,

52:18 but I've done from time to time or an ice bath

52:21 that's going to then

52:22 have a rebound increase in body temperature

52:24 and is going to phase advance my clock.

52:26 That peak in the afternoon is going to come

52:28 about an hour earlier.

52:30 I'm going to want to go to bed earlier, later that night.

52:33 So you can start to play these games

52:34 with timing and hot and cold,

52:36 with meals whether or not you eat, or you don't eat,

52:38 and with light exposure,

52:40 whether or not you view light or you don't view light.

52:42 So now you can start to see why understanding

52:44 the core mechanics of a system

52:46 can really give you the most flexibility because

52:50 I could spend the next 25 years of my life

52:53 answering every question about every

52:55 nuance pattern of travel.

52:56 Well, we're going to Sydney and then we're going there,

52:58 what should I do?

52:59 But that's on you.

53:00 You need to figure out

53:02 your temperature minimum and your temperature peak,

53:03 if you like, and then use these parameters to

53:06 it gives you flexibility.

53:07 And that really underscores the most important thing

53:09 is that when you understand mechanism it's not about

53:12 being neurotically attached to a specific protocol,

53:14 it's the opposite.

53:15 It gives you power to not be neurotically attached

53:18 to a specific protocol.

53:20 It can give you great confidence and flexibility

53:22 in being able to shift your body rhythms however you want.

53:24 And when things get out of whack

53:25 you can tuck them right back into place.

53:28 One thing that's common

53:30 is that people need to do a quick trip.

53:32 It's not always that you're going to go to,

53:34 you know on vacation for two weeks or,

53:36 you know, work someplace else for weeks on end.

53:41 If your trip is 48 hours or less,

53:44 stay on your home schedule.

53:46 This can be tough and it may require scheduling meetings

53:50 according to your home schedule,

53:52 but if you can somehow manage that

53:55 the best thing to do would be to stay on your home schedule.

53:58 Your clock is not going to shift more than a couple hours,

54:01 even if you do everything correctly

54:04 in one day, okay?

54:06 So if I were to travel, say to Europe,

54:09 I've actually done this,

54:10 I did a 24 hour trip to Basel, Switzerland,

54:12 gave a talk and came back, people thought I was crazy but,

54:15 I had a little bit of travel fatigue

54:16 'cause remember there's fatigue

54:17 from the actual travel experience.

54:19 The novelty of it, the air is never great on the planes,

54:23 this was even true before there were mask requirements

54:25 and things like that.

54:27 There's the travel fatigue

54:28 but you don't throw your clock off.

54:30 If you stay 48 hours,

54:33 then you start to shift a little bit.

54:36 72, that's when you start running into trouble.

54:38 The transit time is also important

54:41 but I would say if it's three days or less,

54:43 stay on your home schedule as much as you can.

54:46 And because sunlight isn't under your control

54:49 unless there's something about you I don't know,

54:52 that's when traveling with some sort of bright light

54:54 like the light pad that I have

54:56 down there that I showed earlier,

54:58 for those of you listening just on audio,

55:00 it sort of looks like an eight and a half by 11 inch pad.

55:03 It's actually not designed for wake up,

55:04 it's actually designed, it's a drawing pad,

55:07 and it emits about 1,000 lux of light.

55:12 And so if you want to travel with something like that,

55:15 you can use that in your hotel room

55:16 to wake up when you like.

55:19 Some people will use night shades,

55:22 you know, not the night shades that you eat

55:24 or that some people say you're not supposed to eat,

55:26 I don't know anything about that,

55:27 but the eye covers to keep light out.

55:32 Those can be very useful on planes and in hotels and so on.

55:36 So you can use light and dark

55:38 or you can travel with your light and dark devices

55:42 so that you can stay on your home schedule

55:44 and get most of your light

55:45 when it would be your normal wake up time back home.

55:48 And what's kind of nice is if you know

55:50 when your circadian dead zone is back home,

55:53 which is generally for most people around

55:56 10:00 AM to about 3:00 PM,

55:59 so basically the rising phase of your temperature,

56:02 then you can also feel free to be outside

56:06 without having to wear sunglasses

56:08 or you don't have to worry about light exposure.

56:09 But if you know that window before your temperature minimum,

56:14 that four to six hour window,

56:15 that's the time when if you're viewing a lot of light

56:17 in your new location,

56:19 you are going to shift your clock pretty considerably

56:21 and then you can come back home and have a terrible time.

56:24 At the end of graduate school, I went to Australia,

56:27 remarkable country, incredible people, incredible wildlife,

56:30 had amazing time, I came back

56:32 and it was the first time in my life

56:34 where I couldn't sleep on a regular schedule.

56:36 I was sleeping in like

56:37 hour long increments throughout the day, it was a nightmare.

56:40 And it took me weeks to get back on target.

56:44 And the way I was able to do that

56:46 was exercising consistently at the same time every 24 hours,

56:50 turning my home into essentially a cave at night,

56:54 even covering up the windows

56:56 and then getting as much bright light in my eyes

56:58 as I possibly could during the day, no sunglasses, etc.

57:01 So it can take some real work

57:03 if your clock gets thrown out of whack.

57:05 There's a phenomenon called ICU psychosis,

57:08 where people that are in

57:10 the intensive care unit in hospitals

57:11 actually lose their mind.

57:13 They become psychotic, hallucinations, etc.

57:18 And it's because of altered circadian cycles.

57:21 We know this 'cause they're exposed to these lights

57:23 and these sounds, people coming in and checking on them.

57:26 They leave the hospital or in some cases,

57:28 there have been experiments where people are placed

57:29 near a window where they get some natural light

57:31 and the psychotic symptoms disappear,

57:33 presuming there weren't psychotic symptoms beforehand,

57:37 before they entered the hospital.

57:38 So it's pretty dramatic what light can do

57:42 to the psyche and to the body.

57:44 So let's talk a little bit

57:47 about a different form of jet lag

57:49 that requires no planes, no trains, no automobiles,

57:52 and that's shift work.

57:55 Shift work is becoming increasingly common.

57:59 Many of us are shift working even though we don't have to.

58:02 We're doing work in the middle of the night,

58:03 we are, you know, working on our computers at odd hours,

58:08 sleeping during the day.

58:09 A lot of people who are under shelter and place type stuff,

58:13 are doing more of this.

58:15 Kids with the drifting school schedules.

58:18 Here's the deal with shift work.

58:19 If there's one rule of thumb for shift work,

58:22 it's that if at all possible,

58:25 you want to stay on the same schedule for at least 14 days,

58:29 including weekends.

58:31 Now that should immediately cue the non shift workers

58:34 to the importance of not getting too far off track

58:37 on the weekend, even if you're not a shift worker.

58:39 So sleeping in on Sunday is not a good idea.

58:44 The most important thing about shift work

58:46 is to stay consistent with your schedule.

58:49 Now, I had a conversation on an Instagram live

58:52 with Samer Hattar, who's a neuroscientist

58:56 at the National Institutes of Mental Health,

58:57 he's actually the head of the chronobiology unit there.

58:59 And he was really emphasizing this point because shift work

59:03 where people are doing the so-called swing shift,

59:05 where they're working four days on one shift

59:07 and four days on or another,

59:08 is extremely detrimental to a number of health parameters.

59:11 It gets the cortisol release from the adrenals

59:14 really out of whack.

59:16 And there're these cortisol spikes at

59:18 various hours of the day, it messes up learning,

59:21 it really disrupts the dopamine system and wellbeing.

59:24 It is a serious, serious problem.

59:26 So if you can negotiate with your employer

59:30 to stay on the same shift for two weeks at a time,

59:34 that's going to be immensely beneficial

59:35 and will help you offset

59:36 a lot of the negative effects of shift work.

59:39 Now, I don't presume that

59:41 all of you are going to be able to do that.

59:43 Some of you just don't have that level of control.

59:46 And of course, I want to acknowledge that

59:48 shift workers are essential, right?

59:51 Of course, first responders, firefighters,

59:53 police officers, paramedics, etc,

59:55 but also pilots, night nurses,

59:58 people working on the hospital wards,

1:00:02 people picking up trash.

1:00:04 These night shifts are critical

1:00:06 to our functioning as a society,

1:00:07 as I'm sure all of you can appreciate.

1:00:11 If you're going to work a shift where

1:00:13 let's say, you start at 4:00 PM and you end at 2:00 AM,

1:00:17 excuse me, then there's some important questions that arise.

1:00:21 For instance, should you see light during your shift?

1:00:26 Well, this is a matter of personal choice

1:00:29 but ideally you want to view as much light as possible

1:00:32 and as is safely possible when you need to be alert.

1:00:35 So that would mean from 4:00 PM to 2:00 AM

1:00:38 and then you would want to sleep.

1:00:42 So using light as a correlate of alertness

1:00:45 and using darkness as a correlate of sleepiness,

1:00:48 what this means is see as much light as you safely can

1:00:51 during the phase of your day when you want to be awake.

1:00:55 So it's the same thing I said

1:00:56 way back at the beginning of this podcast episode.

1:00:59 And see as little light as safely possible

1:01:02 and it allows you to function during the time

1:01:05 when you want to be asleep.

1:01:06 So if you're finishing out that 2:00 AM shift,

1:01:08 that's when you would want to avoid bright light exposure,

1:01:12 you'd want to go home,

1:01:13 you'd really want to avoid watching TV if possible.

1:01:16 If you need that in order to fall asleep,

1:01:18 that would be a case where

1:01:19 something like dimming the screen, plus blue blockers,

1:01:23 if that's in your practice

1:01:26 or you want to do that would be helpful

1:01:27 and then going to sleep and then you'll probably wake up

1:01:30 late in the afternoon or early afternoon.

1:01:33 Some of you might say, wait,

1:01:34 Huberman, I thought you don't like blue blockers.

1:01:36 I never said I don't like blue blockers.

1:01:37 I don't like people wearing blue blockers

1:01:38 at the time of day when they want to be alert.

1:01:40 And I don't like people asserting that blue blockers

1:01:43 can prevent circadian shifts

1:01:45 simply because people are wearing them.

1:01:46 The brightness of light is what's important

1:01:47 it's not about the blue.

1:01:49 So if you want to wear them, wear them,

1:01:53 or just dim the lights or turn the lights off.

1:01:56 So let's say you go to sleep at,

1:01:59 you get home after this 4:00 PM to 2:00 AM shift,

1:02:02 you maybe eat something, you go to sleep,

1:02:05 and you wake up and it's noon or 1:00 PM.

1:02:10 Should you get light in your eyes?

1:02:13 Well, your first assumption

1:02:14 based on what I've said previously might be

1:02:16 that you're in the circadian dead zone

1:02:17 that you can't because it's noon 1:00 PM.

1:02:20 But you're not in the circadian dead zone

1:02:21 because you're somebody who goes to sleep

1:02:25 early in the morning at 2:00 AM.

1:02:27 So it's not like the circadian dead zone

1:02:29 is a strict time of day, it's an internal biological clock.

1:02:34 So what do you need to know?

1:02:36 You guessed it, you need to know your temperature minimum.

1:02:39 You need to know whether not

1:02:40 your temperature is increasing or decreasing.

1:02:43 And now we can make this whole thing even simpler

1:02:45 and just say,

1:02:46 if your temperature is decreasing, avoid light.

1:02:51 If your temperature is increasing, get light.

1:02:55 It's that simple, okay?

1:02:58 If your temperature is decreasing, avoid light,

1:03:01 if your temperature is increasing, get light.

1:03:04 The shift worker who works from 4:00 PM until 2:00 AM

1:03:09 has a temperature rhythm that's very different than mine

1:03:12 where I wake up around 6:00 AM, 5:00 AM,

1:03:15 and I go to sleep around 11:00 PM, okay?

1:03:19 We both have a 24 hour-ish circadian cycle,

1:03:23 except mine is more aligned to the rise

1:03:26 and setting of the sun and there's is not, right?

1:03:29 So you have to know your internal temperature rhythm.

1:03:33 And no you don't have to

1:03:34 walk around with a thermometer wherever,

1:03:38 taking your temperature.

1:03:39 Although it'd be great

1:03:40 if some of the devices that are out there,

1:03:42 you know, people are counting their steps,

1:03:43 I think it'd be great if people had

1:03:45 a circadian body temperature measurement.

1:03:47 I'm not involved in any of this device development

1:03:48 but I think it's a real call to arms, pun intended,

1:03:52 to have a wristband that would measure temperature

1:03:55 and would tell you your temperature minimum

1:03:56 when you travel or whatnot.

1:03:57 I don't know, maybe some of these devices already do that.

1:04:00 But if they don't, they should.

1:04:02 It's absolutely absurd to me

1:04:03 why we wouldn't have the simple measurement,

1:04:05 very easy to get that kind of information.

1:04:07 You don't even need the exact temperature read

1:04:10 all you need to know is the high and low point.

1:04:13 So let's say you're a shift worker

1:04:14 who really is nocturnal, you're flipped.

1:04:18 Well, you want to stay on that nocturnal schedule.

1:04:20 Now that can be very hard on families

1:04:22 and social life of all kinds.

1:04:25 But the person who is working say from,

1:04:28 you know, 8:00 PM, like sundown to sunrise,

1:04:33 this raises a question.

1:04:34 Should they be looking at the sunrise

1:04:37 and should they be watching the sunset?

1:04:39 Waking up with a sunset, going asleep at the sunrise.

1:04:43 You think, well, is that light going to throw them off?

1:04:45 Ah, probably not.

1:04:47 It's just actually going to invert what sunrise and sunset are.

1:04:50 When they're waking up in the morning,

1:04:52 if they look at the, you know,

1:04:54 they get some sunlight in their eyes, they look at the sun

1:04:56 and get some bright light from devices

1:04:58 or overhead lights in their apartment or home,

1:05:01 well, that's going to tend to wake them up

1:05:04 if it's in the evening, right?

1:05:06 So it's, you know I don't know if I stated that clearly,

1:05:08 but if in the evening the sun is setting

1:05:10 and they're looking at that setting sun,

1:05:11 that is the morning sun for that person

1:05:15 and it will wake them up for their night shift.

1:05:18 So temperature rising.

1:05:20 Then toward morning, what's happening?

1:05:22 Okay, well, they're closing out their work shift.

1:05:24 You're going home, the sun is rising.

1:05:27 Do you look at the rising sun?

1:05:28 Well, based on what you now know

1:05:31 your eyes are very sensitive

1:05:32 to resetting of circadian clocks.

1:05:34 What will it do at that time?

1:05:35 If this were a classroom,

1:05:36 I would either cold call on somebody

1:05:38 or I'd wait for the oh, oh, oh, oh person

1:05:40 in the audience that inevitably exists.

1:05:43 So temperature is for that person,

1:05:46 they've been up for a while,

1:05:48 temperature is falling, not rising.

1:05:50 For me it will be rising.

1:05:52 But 'cause I'm diurnal, I'm awake during the day.

1:05:56 For that person the temperature's falling

1:05:58 and so they view light while temperature is falling.

1:06:01 What's it going to do?

1:06:02 It's going to phase delay them.

1:06:03 It's going to make it harder for them to get to sleep

1:06:06 the following night.

1:06:07 So you would say that person should watch the setting sun

1:06:10 to help them wake up

1:06:12 'cause they're going to work the night shift,

1:06:13 but should probably have sunglasses on

1:06:15 or avoid viewing bright light before they go to sleep.

1:06:19 So it's the same thing.

1:06:20 They're just on an inverted as a typical person

1:06:22 who's diurnal, but they're on an inverted schedule.

1:06:25 And so I'm really trying hard here

1:06:28 to make this all really clear.

1:06:31 There are kind of two patterns of requests in the world

1:06:35 I'm noticing as I've kind of ventured into the

1:06:38 this landscape of social media and podcasts.

1:06:40 There are people who want to know every detail

1:06:42 and want to quantify everything

1:06:43 'cause they want to get exactly right.

1:06:45 These are like the graduate students

1:06:47 and students that don't want to make a mistake.

1:06:49 And to quote my graduate advisor,

1:06:51 provided the mistakes are not dangerous,

1:06:54 certainly not lethal,

1:06:57 you kind of want to make a few little mistakes

1:06:59 so that you can adjust, right?

1:07:01 You don't want to endanger yourself.

1:07:03 But it's actually, you're not going to get things perfect,

1:07:05 that's called learning.

1:07:06 Learning is when you realize, ah, I viewed the sun this time

1:07:08 and then I stayed up and it really messed me up,

1:07:11 I'll never do that again.

1:07:14 The other category of people seem to want

1:07:18 the one size fits all kind of like

1:07:20 give me this pill or give me this protocol.

1:07:22 And those things generally work

1:07:25 but they don't afford people flexibility.

1:07:27 And if there's anything like that,

1:07:29 it's this temperature minimum thing that I've been just

1:07:32 hammering on again and again and again today

1:07:34 because it's something that you own

1:07:36 and that you can really use

1:07:38 as a key landmark for shifting your clock.

1:07:41 I suppose there's a third category,

1:07:44 which is, people accept that

1:07:47 biological systems are actually much more forgiving

1:07:49 than the way they're sometimes described.

1:07:52 And I'm going to use this as an opportunity

1:07:53 to editorialize a little bit.

1:07:56 You know, there's so much made of sleep debt.

1:07:58 Look there isn't an IRS equivalent for sleep.

1:08:01 They're not going to come around

1:08:02 and try and collect all the sleep that you didn't get.

1:08:05 No one really knows what the consequences are going to be

1:08:09 for you and for me and for the next person

1:08:12 for the sleep you didn't get.

1:08:13 You can't really recover the sleep you missed out on,

1:08:16 but you also don't want to get

1:08:18 neurotically attached to a schedule

1:08:19 because there's this thing called sleep anxiety

1:08:21 and then people have trouble

1:08:22 falling asleep and staying asleep.

1:08:24 So I want to spend a moment on that

1:08:25 and go back to a theme that I've said many times before,

1:08:29 because these tools work

1:08:31 what I called NSDR, non-sleep deep rest.

1:08:33 So this would be hypnosis, I gave you the link,

1:08:36 but I'll say it again, reveriehealth.com

1:08:39 for clinically tested, research tested free hypnosis

1:08:44 for anxiety but also for sleep.

1:08:46 Those are very beneficial people.

1:08:48 NSDR protocols, non-sleep deep rest protocols

1:08:50 for things like yoga nidra, I provided some links to those

1:08:54 in the caption for episode two.

1:08:56 These things really work.

1:08:57 Last night, I woke up, I went to bed about 10:30,

1:09:00 I woke up at three in the morning,

1:09:02 I knew I wasn't feeling rested.

1:09:04 I did a NSDR protocol, I fell back asleep,

1:09:08 I woke up at 6:30, okay.

1:09:10 You need to teach your brain and your nervous system

1:09:13 how to turn off your thoughts and go to sleep.

1:09:15 And ideally you do that without medication

1:09:17 unless there's a real need,

1:09:18 you do that through these behavioral protocols.

1:09:20 They work because they involve

1:09:22 using the body to shift the mind

1:09:24 not trying to just turn off your thoughts

1:09:26 in the middle of the night.

1:09:27 Now there are periods of life

1:09:28 where things are stressful and people are concerned

1:09:30 and you will have some struggle getting and staying asleep.

1:09:35 And there's, that really has to do more with anxiety

1:09:39 which NSDR protocols also can help with.

1:09:42 As I always say, do them in the middle of the night

1:09:43 if you wake up and you want to go back to sleep

1:09:45 during the middle of the day,

1:09:46 to teach your nervous system to calm down

1:09:47 and do them first thing in the morning

1:09:48 if you didn't feel you got enough sleep.

1:09:49 In other words, do them whenever

1:09:51 you have an opportunity to do them

1:09:53 because they really can help you learn how to turn on

1:09:57 the parasympathetic/calming arm

1:10:00 of your autonomic nervous system.

1:10:02 There's no other way that I'm aware of

1:10:05 to teach your system to slow down

1:10:07 and turn off your thoughts and go back to sleep.

1:10:09 But these are powerful protocols,

1:10:10 and there's a lot of research now

1:10:12 to support the fact that they can really help.

1:10:15 Meditation would be another example.

1:10:19 Certain kinds of meditation involve focus and alertness.

1:10:23 Those are slightly different than meditations that involve

1:10:25 lack of focus and attention to say internal states.

1:10:30 I'm going to pause there,

1:10:31 and then I want to talk about kids and the elderly.

1:10:34 In other words, how do we control

1:10:37 sleep and circadian rhythms and wakefulness

1:10:39 in babies, adolescents, teens, and aged folks.

1:10:44 All right, before we talk about sleep in kids,

1:10:49 I want to tell a little story.

1:10:50 It's not a joke, many of you will be relieved

1:10:53 that I'm not going to try and tell another joke this episode.

1:10:57 Which is the relationship between light,

1:11:00 skin and pelage color,

1:11:03 dopamine and reproduction, mating.

1:11:09 So many seasonally breeding animals,

1:11:14 Siberian hamsters which I mentioned earlier,

1:11:16 rabbits, fox, other animals,

1:11:18 change their color of their coat.

1:11:22 In the winter they tend to be a lighter color,

1:11:24 sometimes pure white,

1:11:26 sometimes with flecks of black or brown.

1:11:30 And in the summer their pelage changes to a color of

1:11:34 you know, brown or red, some other vastly different color.

1:11:39 That shift is controlled by light and by melatonin.

1:11:45 This has an interesting correlate in humans.

1:11:48 So humans obviously have different skin tones

1:11:52 just genetically because of the amount of melanin

1:11:56 in one skin, depending on genetic background.

1:12:00 But of course sunlight will increase the amount of melanin

1:12:03 in the skin regardless, right?

1:12:05 This is suntan, sunburn, etc, bronzing, whatever.

1:12:12 The whole system is wired so that shifts in skin color

1:12:16 and shifts in these cells within the eye and melatonin

1:12:20 are actually very closely linked.

1:12:22 So here's the story.

1:12:24 Many years ago, meaning about 10 years ago, 15 years ago,

1:12:30 let's see it was 20 years ago, forgive me.

1:12:35 A guy named Iggy Provencio

1:12:37 who was running his own lab at uniformed armed services,

1:12:42 this is a standard biological laboratory,

1:12:45 discovered that there was an opsin in the eye

1:12:50 in the cells of the eye

1:12:51 that connect to the rest of the brain called melanopsin.

1:12:54 Melanopsin, as many of you now know

1:12:56 is the opsin, it's like a pigment, it absorbs light.

1:13:00 It is the opsin that converts light into electrical signals

1:13:03 to then set the circadian clock.

1:13:07 Iggy discovered melanopsin

1:13:09 because it was similar in form

1:13:14 to what was in frog melanophores.

1:13:18 It was actually in the skin of frogs

1:13:21 that allowed those frogs to go from

1:13:23 pale white, when it was dark,

1:13:26 for most of the 24 hour cycle,

1:13:28 to pigmented green or brown for a frog.

1:13:34 So there's this relationship between the cells in our eye

1:13:37 and the pigment cells of our skin.

1:13:40 And we also know that in long days, there's more breeding.

1:13:44 How does that work?

1:13:45 Well that's actually from dopamine

1:13:47 triggering increases in testosterone, mainly in males,

1:13:51 and estrogen mainly in females although of course,

1:13:53 there's testosterone estrogen in both sexes.

1:13:57 So we have this kind of pathway where it's light,

1:14:01 increases in the melanin,

1:14:03 dopamine and reproduction on the one hand

1:14:05 and lack of light, melatonin,

1:14:09 decreases in the darkness of skin,

1:14:11 less melanin in the skin,

1:14:14 or in the case of an animal with fur,

1:14:16 white fur and no reproduction on the other hand.

1:14:19 And humans don't actually shift their breeding patterns

1:14:25 tremendously from long days and short days,

1:14:28 although there are some data that there's some shifts.

1:14:31 We also don't radically change our skin color

1:14:34 depending on how much sunlight exposure we have.

1:14:37 But the simple way to put this is,

1:14:39 when days are long,

1:14:41 there's a lot more dopamine

1:14:43 and we feel really good

1:14:44 and there's a lot more breeding and breeding-like behavior.

1:14:48 When days are short, there's a lot less dopamine

1:14:51 and a lot less breeding behavior

1:14:53 because these pathways are very highly conserved.

1:14:57 Now what's interesting is that,

1:15:00 as we've moved into a modern society

1:15:03 where much of our waking days

1:15:06 we are looking at screens, which is fine,

1:15:08 'cause we're getting a lot of light that way

1:15:09 although not as much as sunlight.

1:15:11 But also at night,

1:15:13 we're getting a lot of light from screens.

1:15:15 What's happened is all these path ways,

1:15:19 melanin in the skin, turnover of skin cells, dopamine,

1:15:23 all of this stuff has become completely disrupted.

1:15:26 Now that's not to say that we should go back

1:15:28 to a time in which we didn't use artificial lights.

1:15:30 But I think the important thing to realize

1:15:32 is that feeling good with getting a lot of light,

1:15:37 the relationship to dopamine and melanin in the skin,

1:15:42 and the good feelings of getting light also on our skin

1:15:46 provided you're not getting burned

1:15:48 or you're not getting excessive UV exposure,

1:15:50 those are not just coincidences.

1:15:53 Those are hard-wired biological mechanisms

1:15:55 that exist in everybody

1:15:56 regardless of how light or dark your skin is to begin with.

1:16:01 There's another point, which is important,

1:16:03 which is that the dopamine system

1:16:05 which is this feel-good molecule

1:16:07 is very closely related

1:16:09 to the testosterone and estrogen in reproductive cycles.

1:16:12 Remember melatonin inhibits gonadotropin-releasing hormone,

1:16:16 luteinizing hormone, and the production of these hormones,

1:16:19 and melatonin is the effector.

1:16:21 It is the hormone of darkness.

1:16:24 So, I just threw a lot of biology at you.

1:16:27 And I'm not saying you're like a Siberian hamster,

1:16:30 at least not in ways that I'm aware of.

1:16:32 I'm not saying that your pelage color is going to change.

1:16:36 Actually the reason people go gray

1:16:37 is because when you're really stressed, did you know this,

1:16:40 that when you're really stressed,

1:16:42 there's an increase in the nerve fibers

1:16:44 that release adrenaline to the hair follicle

1:16:48 and that activates peroxide groups in the hair follicle

1:16:52 that cause the hair to actually go gray or white.

1:16:55 So actually stress does make your hair gray or white.

1:16:58 Aging does it too.

1:17:02 That was a brief aside,

1:17:03 but for those of you that are interested in

1:17:05 the relationship between light and skin tone

1:17:07 and all that kind of stuff, I thought you might find it

1:17:09 interesting that the cells in your eye

1:17:10 are a lot like these skin cells in frogs or in animals

1:17:15 that shift their entire color and sometimes metamorphosize.

1:17:20 You know, there are some species that literally

1:17:21 change shape in their reproductive organs.

1:17:23 In fact, if that wasn't weird enough,

1:17:25 when I was in graduate school at Berkeley,

1:17:27 there was another graduate student studying a species

1:17:30 of hermaphroditic mole, right, those little things that dig,

1:17:35 hermaphrodite mole that would change

1:17:37 from having ovaries to testes and back again

1:17:41 depending on day life.

1:17:43 Super cool, super different,

1:17:47 and wild biological mechanism.

1:17:50 If you're wondering how those animals reproduce

1:17:52 they actually adjust the numbers of males and females

1:17:55 depending on the density of males and females.

1:17:56 So if there are too many males,

1:17:59 some of the males turn their testes into ovaries.

1:18:02 And if there're too many females,

1:18:04 they turn their ovaries into testes.

1:18:05 They actually are true hermaphroditic animals

1:18:08 as opposed to as pseudo hermaphrodite animals.

1:18:11 Okay, let's get back on track.

1:18:13 Let's talk about the animal that most of you care about

1:18:17 which is the human animal.

1:18:19 New parents and babies.

1:18:22 All right, as I mentioned earlier,

1:18:23 melatonin is not cyclic, it's not cycling in babies,

1:18:28 it's more phasic.

1:18:29 It's being released at a kind of a constant level.

1:18:32 And babies tend to be smaller than adults, they are.

1:18:35 And so those concentrations of melatonin are very high.

1:18:38 As the baby grows, those concentrations

1:18:40 per unit volume are going to go down.

1:18:44 Babies are not born with a typical sleep wake cycle.

1:18:47 And now all the parents are saying,

1:18:49 tell me something I didn't know.

1:18:51 They also have, and I really want to emphasize this,

1:18:55 they also have much more sensitive optics of the eye.

1:18:59 So a number of people have asked me, you know,

1:19:02 should I be exposing my baby to sunlight?

1:19:04 You don't want to avoid sunlight,

1:19:06 but their eyes are very sensitive,

1:19:08 the optics of their eyes aren't quite developed

1:19:10 so much so that you know when you look at a newborn baby

1:19:14 and they look a little glassy-eyed

1:19:16 and they're kind of looking through you

1:19:17 or even a young child.

1:19:19 A lot of people think that they're seeing you

1:19:21 the way that you're seeing them.

1:19:23 Hate to break it to you, but if you ever can just google

1:19:28 visual image of a like a one month old.

1:19:32 The optics of their eyes are so poor

1:19:34 that you're a cloudy image.

1:19:35 They're not seeing your fine detail.

1:19:38 As the optics get better,

1:19:40 then they will see you with more and more clarity.

1:19:43 But a lot of that is clearing of the lens

1:19:45 and some of the other aqueous features of the newborn eye,

1:19:48 they don't see very well.

1:19:51 But they also don't have such great ways

1:19:54 of adjusting to bright light.

1:19:55 And so babies have a natural aversion to bright lights.

1:19:58 So you really want to avoid

1:20:00 trying to use sunlight or really bright light

1:20:02 in the same way that you would for an adult

1:20:04 on a young baby or child.

1:20:06 As children get older however,

1:20:10 melatonin does start to become slightly more cyclic,

1:20:13 slightly more cycled,

1:20:14 and their body temperature rhythms also start to

1:20:17 fall into a more regular, not quite 24 hour rhythm,

1:20:20 they're more of these ultradian rhythms.

1:20:22 So in episode, I think it was one or two of the podcast,

1:20:26 or maybe both, we talked about these 90 minute

1:20:28 so-called ultradian rhythms, where every 90 minutes

1:20:33 babies are going through a cycle of body temperature

1:20:37 and some other hormonal features.

1:20:39 I mean, so much is changing in their system.

1:20:42 So what to do if a child isn't sleeping?

1:20:45 You can use phases of darkness and phases of light

1:20:49 but they're going to have to be shortened

1:20:50 in order to try and encourage sleep

1:20:52 when you want the child to sleep.

1:20:53 It's not that they're just not going to fall

1:20:55 into an adult-like regime

1:20:57 of a temperature minimum and a temperature maximum.

1:21:00 Their temperature minimums and maximums

1:21:01 are fluctuating much more quickly.

1:21:03 And it varies tremendously.

1:21:06 Actually there's an interesting literature

1:21:08 of whether or not they have siblings,

1:21:10 whether or not they're twins,

1:21:11 whether or not they're in a nursery environment,

1:21:13 whether or not they're alone,

1:21:14 hopefully the baby's not alone, but you know what I mean,

1:21:16 that they're sleeping alone in a room

1:21:17 while you're in the other room.

1:21:19 There are a couple of things that seem to help

1:21:21 which is getting the overall environment

1:21:23 into a 24 hour schedule.

1:21:25 So having the room slightly colder,

1:21:27 obviously you want babies to be nice and cozy,

1:21:30 slightly colder when you would like them to be asleep,

1:21:32 slightly warmer for the times

1:21:34 you would like them to be awake.

1:21:35 Babies tend to run pretty hot anyway.

1:21:39 And obviously you want to be very careful

1:21:43 about avoiding all extremes of temperature, cold or hot.

1:21:48 So if they're going through these 90 minute cycles,

1:21:51 you're going to have to adjust

1:21:52 to those 90 minute cycles as well.

1:21:53 So then people say, well, that's not going to help me at all

1:21:55 because how do I deal with the fact

1:21:57 that I need to be up every 90 minutes at night?

1:21:59 There are a couple tools that can be helpful.

1:22:02 The first one is going to be to try and understand

1:22:06 the relationship between calm and deep sleep.

1:22:09 So the autonomic nervous system

1:22:11 can put us into states of panic,

1:22:14 where that's kind of seesaw of autonomic alertness,

1:22:16 goes all the way to panic.

1:22:18 Or it can be alertness, or it can be alert and calm, right?

1:22:20 So there's a range there, it's a continuum.

1:22:23 It can also be that you're in deep sleep,

1:22:26 so the other end of the seesaw is way up

1:22:27 or you're your in light sleep or you're kind of sleepy,

1:22:30 or you're just feeling kind of relaxed.

1:22:33 Perhaps the most important thing

1:22:36 if you're having to map to a baby schedule

1:22:39 in order to make sure that they're getting

1:22:41 changings, and nursing, etc, at the appropriate times,

1:22:44 is to try and maintain,

1:22:48 if you can't sleep or you can't sleep continuously,

1:22:51 to try and maintain your autonomic nervous system

1:22:56 in a place where you're not

1:22:58 going into heightened states of alertness

1:23:00 when you would ideally be sleeping.

1:23:03 Now, I realize that this could be translated to

1:23:06 try and stay calm while you're sleep deprived,

1:23:07 which is very hard for people to do.

1:23:10 But this is where

1:23:11 the non-sleep deep rest protocols surface again

1:23:13 and can potentially be very beneficial

1:23:16 for people to be able to recover, not necessarily sleep,

1:23:19 but for them to maintain

1:23:21 a certain amount of autonomic regulation.

1:23:24 So what would this look like?

1:23:25 This would look like, the baby goes down,

1:23:27 maybe it's only going to go down for 45 minutes.

1:23:29 If you can capture sleep, capture sleep.

1:23:33 There are some data showing what's called polyphasic sleep.

1:23:35 If you can sleep in 45 minute increments or batches,

1:23:39 even if it's spread throughout the day

1:23:40 with periods of wakefulness in between,

1:23:42 as miserable as that sound,

1:23:43 there are actually some adults that have

1:23:44 deliberately employed that,

1:23:46 who don't have children for the sake of work productivity.

1:23:49 And it does tend to reduce

1:23:50 the total overall amount of sleep that you need.

1:23:53 It is a very hard schedule for most people to maintain

1:23:55 but if you have a baby, the baby may be throwing you

1:23:57 into that kind of schedule anyway.

1:23:58 So if you can get 45 minutes sleep while they sleep, great.

1:24:02 If you can get another 45 minutes after waking

1:24:03 and then they go back down to sleep, great.

1:24:05 So as many phases of sleep as you can get.

1:24:07 But if you can't sleep

1:24:09 the data on non-sleep deep rest type protocols

1:24:12 does show that at least from a neurochemical level,

1:24:15 I want to be clear what that means,

1:24:16 reset of things like dopamine levels in the basal ganglia

1:24:20 measured by things like positron emission tomography, etc.

1:24:23 Those things tend to reset themselves pretty well

1:24:26 if you can access these deep rest state.

1:24:29 So that means not being alert

1:24:32 throughout the entire time that the baby is sleeping.

1:24:34 Trying to sort of mirror the baby's sleep cycle

1:24:37 which can be brutal for certain people,

1:24:39 and especially if you're trying to prepare meals

1:24:40 and do all these things.

1:24:41 So I do recognize

1:24:42 that there are a lot of constraints on parenting

1:24:43 not just mapping on your baby's sleep schedule.

1:24:46 As children approach ages one, two, three, four,

1:24:51 that's when certainly the optics of the eyes have improved

1:24:54 but you don't want to damage the eyes of course,

1:24:56 with very bright light.

1:24:58 They are much more sensitive even until

1:25:00 they're kind of 10, 11 years old.

1:25:04 And we'll talk about vision in children in a moment.

1:25:06 But trying to get longer and longer batches of sleep

1:25:11 through, hopefully not through the use

1:25:13 of administering melatonin to the kids

1:25:15 'cause that's what I talked about before

1:25:17 why that could potentially be detrimental

1:25:19 talk about that with your doctor.

1:25:21 But more so trying to get longer blocks of sleep

1:25:25 that map onto these ultradian cycles.

1:25:28 So it would be better off to get a three hour,

1:25:30 like two-90 minute cycles, than a four hour batch of sleep

1:25:34 because waking up in the middle of those ultradian cycles

1:25:36 can just be brutal for parent and kid.

1:25:39 So if one can't get a full six or 10,

1:25:42 or some kids should even be sleeping 12 hours

1:25:44 when they're growing quickly,

1:25:45 trying to get batches of sleep

1:25:47 even if they're fractured throughout the 24 hour cycle

1:25:51 that are matched more to these 90 minute cycles,

1:25:54 meaning maybe one ultradian cycle of 90 minutes,

1:25:56 or two back to back, or three back to back to back.

1:26:01 That's going to be better than waking up

1:26:02 in the middle of an ultradian cycle.

1:26:04 It's just going to set any number of other things

1:26:06 in a better direction than were you to try to say,

1:26:10 just enforce or force a full eight or 10 hours of sleep.

1:26:15 That's at least what the literature shows.

1:26:17 Some kids sleep great through the night,

1:26:19 starting at a very young age, others don't.

1:26:20 I typically hear from people

1:26:22 who are struggling tremendously,

1:26:24 they're losing their mind understandably,

1:26:26 because they're not sleeping, their kid's not sleeping and,

1:26:29 or their kid is sleeping for such brief periods.

1:26:31 So in other words, try and access deep calm

1:26:33 if you can't sleep, try and access sleep, if you can sleep

1:26:35 even if it's fractured.

1:26:37 And then you say, well, what about all the sunlight viewing

1:26:39 and the exercise stuff?

1:26:41 When sleep is really, really dismantled,

1:26:46 meaning it's happening in various times of day or night,

1:26:49 that's especially, at those times

1:26:52 it's going to be especially important for the parent

1:26:54 to get morning and evening sunlight

1:26:56 because your circadian clock is going into a tailspin

1:26:59 and it basically wants to anchor to something.

1:27:01 So you want to give it two anchors, morning and evening light.

1:27:05 Okay, so this is rather different

1:27:07 than what I described for shift work,

1:27:09 this is when things are really chaotic

1:27:10 and you're just not able to sleep.

1:27:12 Similar circumstances can arise

1:27:13 if you're taking care of a very sick loved one,

1:27:15 you're up all night.

1:27:16 Try and stay calm using NSDR protocols,

1:27:19 I know it's harder to do than to say,

1:27:22 but those protocols are there, they're free,

1:27:24 there's research to support them.

1:27:26 Try and get sleep whenever you can

1:27:28 but also try to get morning sunlight

1:27:31 and evening sunlight in your eyes if you can

1:27:34 and if you can't get that, use artificial light, okay?

1:27:38 What about later life?

1:27:39 So kids now, adolescents, teens,

1:27:42 it is true that teens have a tendency to wake up later

1:27:46 and go to sleep later.

1:27:47 In part, just because they're sleeping a lot more.

1:27:50 They're churning out gonadotropin-releasing hormone

1:27:52 and luteinizing hormone.

1:27:53 Their whole bodies are changing.

1:27:56 I don't know whether or not people realize this,

1:27:58 but the fastest rate of aging

1:28:00 that any of us will ever undergo is puberty.

1:28:04 That is the fastest rate of aging.

1:28:06 And so there's a huge number of biological processes

1:28:08 that are happening during puberty,

1:28:10 probably devote a whole episode

1:28:11 to puberty as a fascinating aspect to the life course

1:28:16 but it is accelerated period of aging.

1:28:19 And the circadian clock mechanisms

1:28:21 sometimes are very intact,

1:28:24 and sometimes they're a little dismantled

1:28:25 and going through some change,

1:28:27 but prioritize the duration of sleep

1:28:31 for adolescents and teens.

1:28:33 Now, if that means they're sleeping until 2:00 PM,

1:28:35 and then waking up and then they're up all night,

1:28:36 the up all night part can become a problem

1:28:38 especially with all the devices,

1:28:39 texting in their rooms or playing video games.

1:28:43 Morning and evening sunlight would be ideal

1:28:45 but some kids are just going to sleep

1:28:46 through the morning sunlight.

1:28:47 However, if you were to measure their temperature,

1:28:49 what you would find is that their temperature minimum

1:28:52 would come later in the morning.

1:28:54 It's not going to be 8:00 AM.

1:28:57 It's going to be maybe even 10:00 AM,

1:28:58 if they're sleeping until 11 or 12.

1:29:01 Or it might be 8:00 AM if they're sleeping until 10.

1:29:03 Remember temperature minimum is two hours

1:29:05 before your average waking time, typically.

1:29:08 So in teens, it maximizes the total amount of sleep.

1:29:11 Try and get regular sunlight either in the morning

1:29:13 or in the evening or both.

1:29:15 But if they're sleeping through the morning sunrise,

1:29:17 that's probably not as much of an issue,

1:29:20 waking them up and depriving them of sleep

1:29:22 is probably worse because their T-min,

1:29:24 their temperature minimum, is actually falling later.

1:29:28 So their circadian dead zone is later, etc.

1:29:30 So I think with adolescents and teens

1:29:32 it makes sense to kind of give them a little bit more rope

1:29:35 in terms of allowing them some leeway

1:29:39 to adjust their own schedule.

1:29:40 Some schools are even starting classes later

1:29:42 on the basis of some very good biology

1:29:45 to support this late shifted rhythm

1:29:46 and this extended sleep phase.

1:29:49 There are data from Dr. Jamie Zeitzer,

1:29:53 Department of Psychiatry and Behavioral Sciences,

1:29:54 and others at Stanford, showing that turning on the lights

1:29:57 in the room of a teen before they wake up

1:30:00 helps them get more sleep the subsequent night,

1:30:03 it also tricks them

1:30:04 into going to sleep a little bit earlier.

1:30:06 But it gives them about 45 minutes more of deep sleep.

1:30:09 And that's been shown statistically,

1:30:11 total sleep time increases as well.

1:30:13 If they're hiding under the covers, that's not going to work,

1:30:15 but their eyes don't have to be open.

1:30:17 I know a few parents now

1:30:18 that are coming in with a flashlight

1:30:19 and flashing their kids over their eyelids

1:30:22 before they wake up in hopes of getting this to work,

1:30:24 some have told me this is working.

1:30:27 That's not part of a standard study.

1:30:30 But it does seem to work because, now you should know why,

1:30:35 because if light's getting through the eyelids,

1:30:37 and it's say 8:00 AM and the kid is still asleep

1:30:40 and they're going to wake up at 10,

1:30:41 you're giving them light

1:30:43 just after or around their temperature minimum,

1:30:47 which is going to make them want to go to sleep earlier.

1:30:50 And in the case of teens,

1:30:51 for some reason we don't quite understand,

1:30:53 sleep longer, about 45 minutes longer,

1:30:55 spend more time in deep sleep.

1:30:57 Adults can do this too, if you can persuade someone

1:30:59 or put your lights on timer

1:31:00 for lights to go on before you wake up,

1:31:03 that's really going to help you wake up earlier, okay.

1:31:06 So if you're starting to hear

1:31:07 some themes are really resounding over and over again,

1:31:11 that should be reassuring to you, right.

1:31:12 That these are core mechanisms.

1:31:15 Fortunately, there aren't 1,000 different mechanisms.

1:31:18 Now in the elderly,

1:31:22 there's a real tendency to want to go to sleep very early

1:31:25 and wake up very early.

1:31:27 And people should talk to their physician.

1:31:31 There is some evidence that melatonin levels

1:31:33 and patterns of melatonin secretion

1:31:36 can become a little chaotic in elderly folks.

1:31:39 What do I mean by elderly?

1:31:40 Well, it's going to differ.

1:31:41 Rates of aging differ, right?

1:31:43 You see some 65 year olds that are struggling to move

1:31:47 and seem much older than some 65 year olds that are,

1:31:50 you know, still hustling around and have tons of energy.

1:31:54 There's a lot of variation,

1:31:55 some of it's genetic, some of it's lifestyle factors,

1:31:58 you know, it really varies.

1:32:00 Certainly lifestyle factors can play an important role

1:32:03 in rates of aging.

1:32:06 I think that the most prominent results

1:32:09 from sleep and circadian rhythms in the elderly are

1:32:13 they need to get as much natural light,

1:32:15 even if it's through windows.

1:32:16 I realize that some elderly folks

1:32:19 can't get outside as easily.

1:32:20 It's not safe for them to do it,

1:32:22 they can't move around as easily.

1:32:25 Exercise can come in various forms

1:32:26 for people that can't get outside

1:32:29 and get a ton of sunlight by jogging or cycling.

1:32:32 If they're not able to do that,

1:32:33 light through window in that case, open window ideally,

1:32:35 but for temperature reasons, etc,

1:32:37 sometimes the window has to be closed.

1:32:39 Getting people near that window

1:32:40 and away from artificial light early in the day,

1:32:43 and away from artificial lights during the night phase

1:32:46 can have a tremendous effect.

1:32:49 And in the elderly that's when melatonin

1:32:52 might be a viable option.

1:32:55 And this should be discussed with a physician, of course,

1:32:57 but you know, you're way past the puberty time point.

1:33:00 In most cases, people who are in their 70s, and 80s,

1:33:04 and 90s, are not churning out

1:33:06 a lot of GnRH and luteinizing hormone to begin with.

1:33:08 And that's where struggles

1:33:10 with falling asleep and staying asleep,

1:33:12 all the same parameters

1:33:14 and things we've described before still apply,

1:33:17 light, exercise, temperature, etc,

1:33:19 but that's where melatonin might be of greatest benefit.

1:33:22 And again, I'm not pushing melatonin here

1:33:24 but I think for elderly folks

1:33:26 who are having trouble falling and staying asleep,

1:33:28 that might be worthwhile.

1:33:31 There are, and I should just also mention that

1:33:34 regular schedule for folks that are elderly

1:33:37 and as much natural light as safely possible,

1:33:40 those are going to be the key levers

1:33:43 for adjusting sleep in circadian schedules.

1:33:47 I've mentioned before in previous podcasts,

1:33:49 other supplements besides melatonin.

1:33:52 And some of those supplements are quite good for sleep.

1:33:54 You know, I'm not a supplement pusher,

1:33:56 I am somebody who takes supplements, I believe in them,

1:34:01 some have worked for me some have not worked as well,

1:34:03 but I certainly believe in getting the behaviors right.

1:34:07 Whether or not it's NSDR protocols, viewing natural light,

1:34:11 exercise, hot baths, or cold showers, or what have you,

1:34:15 behavioral protocols first.

1:34:18 There are some supplements that

1:34:19 I've mentioned in previous podcasts

1:34:21 but I've seemed to get a lot of questions about.

1:34:22 So I just want to take a couple minutes and just talk about

1:34:24 some of the supplements that can be beneficial

1:34:26 for helping turning off thinking, accessing deeper sleep,

1:34:30 and even being able to compact your sleep schedule

1:34:33 into a shorter period of hours,

1:34:35 meaning getting by well with less sleep.

1:34:37 People take a lot of sleeping pills.

1:34:39 I'm not going to tell people not to take sleeping pills.

1:34:42 They can be very problematic, habit-forming,

1:34:45 high side-effect incidents in many cases,

1:34:49 some people can handle them just fine.

1:34:51 Again, I'm no physician,

1:34:54 I'm not prescribing anything.

1:34:55 I'm a professor, so I profess a lot of things

1:34:58 some of which are my opinion.

1:34:59 Although, if you look at the scientific literature,

1:35:02 there are some impressive data around some

1:35:04 non-prescription drug type supplements

1:35:06 that have fairly high safety margins

1:35:09 that you might consider

1:35:10 but you should talk to your doctor always

1:35:11 before adding or taking anything

1:35:13 out of your health regimes, right?

1:35:15 Your health is not my responsibility,

1:35:17 it's your responsibility, so be a stringent filter.

1:35:20 Along those lines, one of the most powerful and useful tools

1:35:23 that I've mentioned here on many times

1:35:24 and I plan to mention many many more times,

1:35:26 is the website examine.com

1:35:29 which I have no affiliation with

1:35:31 but is a wonderful site that links you to

1:35:34 quality peer reviewed studies

1:35:36 relating to just about any supplement

1:35:38 including some safety warnings.

1:35:40 Will also tell you what subjects,

1:35:41 whether or not it was rats, cats, elderly folks or kids,

1:35:45 that a given study was done on,

1:35:47 which is important, can be kind of hard to pull from

1:35:50 sites where people are just advertising supplements, right?

1:35:52 They usually don't tell you what the study was

1:35:54 and who were these rats, who were these kids, etc.

1:36:02 There are three supplements that at least for me

1:36:04 have had a tremendously positive effect on my sleep

1:36:08 that some of you might consider.

1:36:11 I would say,

1:36:12 if you're doing everything properly behaviorally

1:36:15 and you're still having issues,

1:36:17 then supplements might be a good thing for you.

1:36:19 Or if you are traveling

1:36:21 and you want a little bit of extra help

1:36:23 in buffering your sleep wakefulness protocols.

1:36:27 Some people like to go just to the supplements.

1:36:29 They're like, what should I take?

1:36:30 I have people in my life that are like,

1:36:32 just tell me what to take, you know.

1:36:33 I'm more of, here's what you might want to do or not do

1:36:37 and then think about what you might want to take or not take.

1:36:39 But personal preference and it's a free country,

1:36:42 so you can do what you like.

1:36:47 Magnesium.

1:36:48 So magnesium has been shown to increase the depth of sleep

1:36:53 and has been shown to decrease the amount of time

1:36:56 that it takes to access sleep, to fall asleep.

1:36:59 It comes in various forms.

1:37:01 I've talked a bunch of times about magnesium threonate,

1:37:04 T-H-R-E-O-N-A-T-E, threonate.

1:37:09 which seems to be the more bioavailable form of magnesium.

1:37:13 And magnesium threonate it seems

1:37:16 is shadowed preferentially to the brain

1:37:19 which is where you want it.

1:37:21 And there's certain transporters,

1:37:23 it actually engages the GABA pathway

1:37:26 which tends to turn off certain areas of the forebrain

1:37:28 and allows you to kind of fall asleep.

1:37:31 There is a study, if you'd like to explore it

1:37:34 since people serious about supplementation

1:37:36 might want to explore the study,

1:37:38 which is Ates et al, A-T-E-S

1:37:41 Dose-Dependent Absorption Profile

1:37:42 of Different Magnesium Compounds.

1:37:45 Looks to me like a quality peer reviewed paper.

1:37:47 I can put the link in the caption,

1:37:50 and it explores all the different forms of magnesium.

1:37:54 It does seem like magnesium glycinate

1:37:56 can be similar to magnesium threonate

1:37:57 in terms of which tissues it is shadow to.

1:37:59 Magnesium malate, M-A-L-A-T-E,

1:38:02 is preferentially shadow to the muscle, it appears,

1:38:04 as opposed to the brain.

1:38:05 So it's going to be more of a muscle repair type thing

1:38:08 or restoring magnesium stores in the periphery

1:38:10 as opposed to the brain.

1:38:11 Magnesium citrate has another name that I won't mention

1:38:16 ingest, because magnesium citrate's main effect,

1:38:20 at least on me and the people I know,

1:38:21 seems to be a laxative effect

1:38:24 as opposed to a cognitive effect.

1:38:25 There's also some evidence that magnesium threonate

1:38:28 can be neuroprotective.

1:38:29 Those data come from quality labs,

1:38:32 mostly rodent studies, not human studies,

1:38:34 but it's kind of interesting.

1:38:36 And again, the safety margins for these things

1:38:37 tend to be pretty high,

1:38:39 but anytime you're going to take something new

1:38:41 you should approach it with caution,

1:38:42 especially since magnesium could be involved

1:38:44 in heart rhythm and things of that sort.

1:38:47 The other supplement that

1:38:49 has been very beneficial for me is theanine.

1:38:51 So this is T-H-E-A-N-I-N-E, theanine,

1:38:55 T-H-E-A-N-I-N-E.

1:38:59 Theanine activates certain GABA pathways

1:39:02 which are involved in turning off

1:39:04 top-down processing and thinking,

1:39:06 making it easier to fall asleep.

1:39:08 And theanine, 100 milligrams to 300 milligrams

1:39:13 has a calming effect.

1:39:15 Theanine is now showing up in a number of different

1:39:18 energy drinks and even some coffees

1:39:20 as a way to try and get people to ingest more

1:39:22 of a given type of coffee 'cause

1:39:24 the idea is it will take away the jitters and the anxiety,

1:39:27 allowing people to drink more coffee.

1:39:29 I'm talking about taking magnesium and theanine

1:39:33 30 to 60 minutes before bedtime

1:39:35 not during the day to quell anxiety,

1:39:37 but rather 30 to 60 minutes before bedtime

1:39:40 with or without food, for me hasn't made a difference.

1:39:43 And the combination of those two things has really helped.

1:39:45 Theanine for sleepwalkers can be a problem.

1:39:49 It does increase the intensity of your dreams,

1:39:51 it gives you very vivid dreams.

1:39:53 So for sleep walkers or people that get night terrors

1:39:56 stay away from theanine is my advice.

1:39:59 Magnesium theanine might be something to explore

1:40:01 for those of you that don't have those issues.

1:40:03 With the emphasis on might.

1:40:05 And then I've talked about a compound,

1:40:07 and last time I talked about the mechanisms of apigenin

1:40:10 which is a derivative of chamomile, A-P-I-G-E-N,

1:40:14 which acts as a little bit of a hypnotic

1:40:16 by activating chloride channels, hyperpolarized neurons,

1:40:19 increases GABA in the brain,

1:40:20 basically makes you feel a little sleepy.

1:40:23 And chamomile, for those of you that read your

1:40:27 what was it that Peter Rabbits

1:40:29 snuck into Mr. McGregor's garden,

1:40:31 ate the chamomile, fell asleep, Mr. Gregory came back.

1:40:33 Okay, anyone flashing back to elementary school?

1:40:35 Okay.

1:40:36 There's a story about chamomile

1:40:38 having these kind of sedative-like effects,

1:40:40 apigenin is highly concentrated chamomile

1:40:42 also has intra-estrogenic effects.

1:40:44 So if you want to keep your estrogen up

1:40:46 you might want to be cautious about apigenin.

1:40:49 That's where things like examine.com become really useful

1:40:52 because you can go to examine you put in apigenin,

1:40:54 and it'll tell you all the things that it does

1:40:56 and all the things that it does can sometimes include

1:40:58 things that you had no idea,

1:40:59 like reducing conversion of certain androgens to estrogens

1:41:05 which you might like or you might want to avoid.

1:41:07 That's up to you and where you want your estrogen levels

1:41:09 depending on who you are and what your life

1:41:11 circumstances and goals are.

1:41:14 A few other things that can help the transition to sleep,

1:41:18 are things like 5-HTP L-tryptophan.

1:41:20 I've talked about why I'm not a fan of those for me,

1:41:23 they tend to throw me into deep sleep

1:41:25 and then I wake up and I can't fall back asleep.

1:41:27 So I don't like to tinker with my serotonin system,

1:41:30 I don't like to tinker with my dopamine system,

1:41:32 for entirely other reasons but

1:41:35 none of which are particularly concerning

1:41:38 it's just that I find that if I increase my dopamine

1:41:40 by taking L-Tyrosine in pill form,

1:41:43 then I crash really hard the next day.

1:41:44 Or if I take 5-HTP L-tryptophan

1:41:47 I fall deeply asleep and then I wake up.

1:41:49 But I didn't mention that there might be ways

1:41:51 to make sleep more compact.

1:41:53 And so this is actually a request to you.

1:41:56 I had a really interesting experience when I was a postdoc.

1:42:00 I went for the first time to an acupuncturist.

1:42:02 I know there're varying

1:42:04 thoughts and opinions out there about acupuncture.

1:42:08 I can't say that I've benefit so much from the acupuncture.

1:42:11 There are now quality peer reviewed studies showing

1:42:14 publishing neuron, Cell Press journal, excellent journal,

1:42:17 showing that acupuncture can stimulate

1:42:20 some anti-inflammatory compounds

1:42:22 depending on where the acupuncture is done.

1:42:23 These are really good studies, came out last year.

1:42:26 I talked about this on Instagram, I may talk about it again.

1:42:28 As well as certain acupuncture sites

1:42:30 that increase inflammation.

1:42:32 So, you know, you can get different types of effects,

1:42:36 you can't just say acupuncture is great across the board.

1:42:39 And I'm assuming that the acupuncturist know

1:42:41 which sites are good for increasing inflammation,

1:42:43 which ones are good for decreasing inflammation.

1:42:46 However, this acupuncturist that I went to

1:42:50 gave me these red pills.

1:42:52 He said, these are minerals for sleep,

1:42:53 and it was remarkable.

1:42:54 I took the red pills.

1:42:56 Isn't that a thing now?

1:42:57 Take the red pill.

1:42:58 I don't know what that means, right,

1:42:59 'cause I'm not tuned in.

1:43:00 But these red pills looked like little M&Ms,

1:43:03 I took a couple of them on his suggestion

1:43:05 and I fell deeply asleep

1:43:06 and four hours later woke up feeling incredibly rested,

1:43:09 more rested than I had ever felt in my entire life

1:43:12 and I never required more than four hours sleep.

1:43:14 Unfortunately, acupuncturist moved away,

1:43:16 I never figured out what was in those red pills.

1:43:18 I didn't get a chance to do the mass spectroscopy,

1:43:20 and I still wonder, he said they were minerals.

1:43:24 So somebody out there knows what these red pills are

1:43:27 and what this compound is.

1:43:28 And it was incredible,

1:43:30 and I would love to know what those are.

1:43:33 So if you know,

1:43:35 please don't go taking red pills at random

1:43:37 to try and recreate this non-experiment experience of mine.

1:43:41 But please do contact me if you find out

1:43:44 or if you're an acupuncturist

1:43:45 and you know what these mysterious red pills were,

1:43:48 because they were pretty awesome.

1:43:51 Once again, I've thrown

1:43:52 a tremendous amount of information at you.

1:43:55 I hope you will figure out your temperature minimum

1:43:58 and start working with that

1:43:59 to access the sleep and wakeful cycles

1:44:03 that you want to access.

1:44:04 I hope that you will explore NSDR.

1:44:07 You might want to explore supplementation

1:44:10 if that's your thing.

1:44:11 You have now access to a lot of mechanism

1:44:14 about sleep and wakefulness.

1:44:16 But in keeping with the theme of this podcast,

1:44:18 where we stay on topic

1:44:20 for an entire month or even slightly more,

1:44:22 we are not done with sleep and wakefulness.

1:44:24 I know this is very different

1:44:26 than the typical podcast format,

1:44:28 where one week it's how to become superhuman

1:44:31 and the next week it's how to, you know,

1:44:34 develop growth mindset and it's kind of all over the place

1:44:37 with episode to episode.

1:44:38 We are staying on track because I really believe

1:44:40 that as we drill deeper and deeper into these mechanisms,

1:44:43 and you start hearing some of the same themes

1:44:45 again and again,

1:44:46 you're going to start to develop an intuition

1:44:49 and an understanding of how these systems work in you

1:44:51 and your particular life circumstances.

1:44:53 And my goal is really to eventually become obsolete.

1:44:56 It's what my graduate advisor used to call

1:44:58 the hit by a bus principle.

1:45:01 She had a somewhat morbid sense of humor and used to be,

1:45:04 well, if I get hit by a bus tomorrow,

1:45:05 what are you going to do without me blabbing at you here?

1:45:09 So I don't want to get hit by a bus,

1:45:11 I plan on living a very long time,

1:45:13 if I have anything to say about it.

1:45:14 But were I to get hit by a bus tomorrow,

1:45:17 what would you do for your sleep and wakefulness, right?

1:45:19 You could put a comment on YouTube,

1:45:21 which I hope you will do.

1:45:22 But if I were hit by a bus and killed

1:45:24 then I wouldn't be able to answer your question.

1:45:27 So know your temperature minimum,

1:45:29 understand light in the early part of the day is valuable.

1:45:32 Light when you want to be awake,

1:45:34 provided it's not so bright it's damaging.

1:45:35 It's great for you whether or not it comes from screens

1:45:37 or sunlight but sunlight's better.

1:45:39 Avoid light in the four to six hours

1:45:42 before your temperature minimum

1:45:43 or else you're going to delay your clock

1:45:45 unless you're traveling and that's what you want to do.

1:45:48 Okay?

1:45:48 Use temperature, increase temperature to shift your clock,

1:45:52 decrease temperature to delay your clock, okay?

1:45:56 Map out your temperature and understand it.

1:45:58 You don't have to know degree by degree across the day,

1:46:01 know your minimum, know your maximum temperature

1:46:03 in your 24 hour cycle

1:46:04 and you'll feel great power through that

1:46:07 because then you'll know also about these ultradian cycles,

1:46:10 these 90 minute cycles within which you can do focused work.

1:46:13 Don't expect the focus to come early,

1:46:15 expect focus to come in the middle

1:46:16 and then kind of taper off.

1:46:18 I talked a little bit about kids,

1:46:19 a little bit about elderly, about parenting,

1:46:21 we are going to continue, there's going to be more.

1:46:23 But now shift workers, travelers,

1:46:25 people that are jet lagging themselves at home,

1:46:27 you now have levers in place.

1:46:30 Information can be powerful but you have to implement it

1:46:33 in ways, obviously safe ways and reasonable ways.

1:46:36 But implementing this knowledge

1:46:38 in the ways that you trust are safe and reasonable for you

1:46:41 is going to be the way that you can

1:46:43 develop a bit of a laboratory about yourself.

1:46:45 I loath the term biohacking, sorry, biohackers.

1:46:49 I don't believe in hacking anything.

1:46:50 I believe in understanding mechanism

1:46:52 and applying the principles of mechanism

1:46:54 for which there are large bodies

1:46:56 of quality peer reviewed data,

1:46:58 and even a whole center of mass around

1:47:00 certain biological principles,

1:47:02 like the effects of light and temperature,

1:47:04 temperature minimums, that will allow you

1:47:06 to shift your biology in the ways that you want it to go.

1:47:08 That will allow you to shift your psychology

1:47:10 in the ways you want to go.

1:47:12 Next podcast episode,

1:47:14 we are going to talk more about a few things.

1:47:17 First of all, we're going to answer more of your questions

1:47:20 'cause during office hours,

1:47:21 I didn't get to all your questions from

1:47:23 the previous episode.

1:47:24 So I do read the comments and we're paying attention

1:47:27 and figuring out the most common questions.

1:47:29 We are going to get to some of the harder topics.

1:47:31 Someone came at me,

1:47:32 it's always fun when somebody does this, they said, well,

1:47:34 these are just the kind of basal low-level questions.

1:47:37 What about the big stuff?

1:47:38 What about dreaming and lucid dreaming and consciousness?

1:47:40 Look, I'll talk about that stuff.

1:47:42 And I'm planning to do that,

1:47:44 some of which in the next episode

1:47:45 and the following episode maybe even.

1:47:47 But I want to give you data.

1:47:49 I want to give you things that are supported by data.

1:47:52 So I will try to speculate as little as possible

1:47:56 because this is a podcast about science

1:47:59 and science-based tools for everyday life.

1:48:01 This is not about me speculating.

1:48:03 Many people have speculated about the role of sleep,

1:48:05 dreaming and consciousness.

1:48:06 Fascinating topics, and a rather circular argument frankly,

1:48:11 it's been going on for centuries.

1:48:12 Someday we'll get there, right now we're concentrating

1:48:15 on these deep biological mechanisms

1:48:17 that make you who you are

1:48:18 and allow you to feel certain ways, good or bad,

1:48:21 allow you to function physically in certain ways,

1:48:25 good or bad, and give you more of a sense of control.

1:48:27 That's my goal here.

1:48:29 Many people have quite graciously asked

1:48:31 how they can help support the podcast.

1:48:33 First of all, thank you, we appreciate the question.

1:48:36 You can support the podcast

1:48:38 by subscribing to the podcast on YouTube,

1:48:41 as well as subscribing on Apple or Spotify.

1:48:45 And you can also leave us comments

1:48:47 and feedback on YouTube and at Apple that really helps.

1:48:51 We would hope the feedback would be positive,

1:48:53 but nonetheless, leave us feedback, ask questions,

1:48:56 we will use those questions

1:48:57 to create future content for the podcast.

1:49:00 As well, if you can recommend the podcast

1:49:02 to friends and family and other people that you think

1:49:04 might find the information of use, that's terrific.

1:49:07 And check out our sponsors

1:49:08 that we mentioned at the beginning.

1:49:10 That's a really great way to help support us

1:49:12 and our ability to bring you this information.

1:49:15 Along those lines, a lot of people have asked me

1:49:17 about supplements and supplement companies.

1:49:21 So up until now I've been reluctant

1:49:25 to recommend specific supplement brands.

1:49:27 The supplement industry is kind of a wild west

1:49:31 of different brands,

1:49:32 different levels of quality and stringency.

1:49:35 It can be very complicated

1:49:37 and what's on the bottle is not always what you're getting.

1:49:40 The quality of what you're getting

1:49:41 varies from company to company,

1:49:42 and even from substance to substance, batch to batch.

1:49:46 So I'm pleased to say that I'm partnering with Thorne,

1:49:50 Thorne, spelled T-H-O-R-N-E,

1:49:53 is a supplement company that works with the Mayo Clinic,

1:49:56 and with pretty much all the major sports team organizations

1:50:00 and that I know to have the highest levels of stringency

1:50:03 in terms of what's in the bottle

1:50:05 matches what's listed on the bottle,

1:50:08 and in terms of the quality

1:50:10 of what they put in those supplements.

1:50:12 So, while I mentioned earlier,

1:50:14 that supplements aren't for everybody.

1:50:16 If you're interested in trying some of these supplements

1:50:18 you might want to check out Thorne.

1:50:20 If you want to do that you can go to

1:50:21 thorne.com/u/huberman.

1:50:27 So it's t-h-o-r-n-e.com,

1:50:31 c-o-m slash the letter u slash huberman,

1:50:36 and if you do that, they'll give you 20% off

1:50:38 any of the supplements

1:50:39 that you happen to purchase from Thorne.

1:50:42 Thanks so much for your time and attention.

1:50:43 I really appreciate it.

1:50:45 See you next time on the Huberman Lab Podcast.

1:50:47 And as always, thanks for your interest in science.

1:50:50 [bright music]