Because I struggle so much with sleep, I am fascinated to learn more about it. Enter a 3-part interview (episodes 47, 48, 49) on Peter Attia’s podcast – The Drive – that came out on April 1, 2019.
Dr. Peter Attia operates a medical practice with offices in New York City and San Diego. He specializes in maximizing performance, lifespan, and healthspan (quality of life). He is a thought leader in physical and mental health. You can read more about his background here. I’ve been following him ever since viewing his dynamic warm-up exercise video that I utilized for coaching my high school Varsity field hockey team.
In this 3-part interview, Dr. Peter Attia interviews Dr. Matthew Walker, author of the international best-seller, Why We Sleep. Dr. Walker is a sleep scientist at Google, where he helps the scientific exploration of sleep in health and disease.
I have listened to each episode at least twice and feel compelled to share excerpts with others for a number of different reasons:
- It’s fascinating. It’s also long and dense, so for those people who don’t want to invest six hours listening time, I will give you my Cliff’s Notes.
- Both doctors are so smart and say words that I’ve never heard (thankfully I’m a decent speller, so I’m able to Google-guess and find the correct spelling and definitions). Sometimes, when they string enough science-y words together to form a sentence, it sounds like gibberish, so I’ve only taken the pieces that really resonate with me.
- The importance of sleep is often underestimated and so interesting. Let’s learn more about it!
- Even though I’ve done my best to curate these interviews, I encourage readers to listen for themselves. Besides the wealth of knowledge that Dr. Matthew Walker offers, he also has a wonderful English accent, so it’s a joy to listen to him speak.
The three parts (plus a short follow-up) are:
Part I: Dangers of Poor Sleep, Alzheimer’s Risk, Mental Health, Memory Consolidation, and More.
Part II: Heart Disease, Cancer, Sexual Function, and the Causes of Sleep Disruption (and Tips to Correct It).
Part III: The Penetrating Effects of Poor Sleep from Metabolism to Performance to Genetics, and the Impact of Caffeine, Alcohol, THC, and CBD on Sleep.
Episode #58 – Sneak peak of AMA (Ask Me Anything): Strategies for Sleeping More, Sleeping Better, and Avoiding Things That are Disrupting Sleep. (AMA’s, along with extensive show notes are available to subscribers only, so if you’re interested in subscribing, click here.
The following quotes are by Dr. Matthew Walker (unless otherwise noted) and have been paraphrased. I have included which specific interview the quote is pulled from, along with the time stamp.
WHY DO WE SLEEP?
(Part I, 10:14) “There is no better demonstration of a gigantic shift in conscious state that happens to almost every single living creature on this planet, every 24 hours.”
(Part I, 11:08) “Twenty years ago, if someone were to ask you, ‘Why do we sleep?’, the crass answer was, ‘We sleep to cure sleepiness.’ That’s the factious equivalent of saying, ‘We eat to cure hunger.’ That tells you nothing about the fundamental nutritional benefits of macro-nutrition, but that’s where we were at with sleep. So it was, for me, this perfect collision of fascination in an innate biological problem and universal behavior conserved across evolution, together with the fact that we did it for a third of our lives, plus the fact that science had not been able to crack this nut. It was one of the last great remaining scientific mysteries.”
(Part I, 17:50) Study at Rochester University in rats: “Your body has a sewage system that you’re all familiar with called the lymphatic system, but it turns out the brain has one. It’s called the glymphatic system, named after the cells in the brain that form this system called the glial cells. They used to think of it as the junk DNA. Of course, what we always learn is that Mother Nature is far too efficient to leave inefficiency on the table. It turns out, they form this sanitization system within the brain, so when you go into deep sleep at night, this sewage system kicks into high gear and those glial cells – which surround the brain cells themselves – shrink in size by up to 200 percent, and then all of a sudden it leaves a vast amount of room for cerebral spinal fluid to start perfusing the brain and washing out the metabolic detritus of wakefulness.
“It would be like New York City at night – all of the buildings shrunk down by 200 percent – they became miniaturized, and then there was this big affluent flush that just happened across Manhattan, to clear out all the debris. And it’s essentially good night, sleep clean, that you get this power cleanse at night.”
(Part I, 1:06:34) “If sleep doesn’t serve an absolutely vital set of functions, it’s the biggest mistake that the evolution process has ever made. We now realize from this constellation of evidence, that Mother Nature did not make a spectacular blunder in putting this thing called an 8-hour need of sleep in place. It is the greatest life support system that you could ever wish for, it is a remarkable health insurance policy, and what’s great is that it’s largely democratic – it’s mostly free – and in terms of a prescription from a doctor, it’s largely painless.”
TYPES OF SLEEP
- (Part I, 27:22) “Regularity: how consistent is your sleep schedule? Are you going to sleep at 1am, then 10pm, and all over the map?
- Continuity of your sleep: is it fragmented? Are you waking up many more times, or is just nice; one long shot.
- Quantity: how much sleep are you getting and how much of the different stages are you getting? And then independent of how regular your sleep is, how continuous your sleep is, and the amount.
- Quality: What is the electrical signature of your sleep? Just because you’re getting eight hours of sleep doesn’t mean that you’re getting eight hours of good, quality deep sleep.”
- (Part I, 41:15) “Non-Rapid Eye Movement sleep, which has been further subdivided into four separate stages, which are unimaginatively called stages 1-4.
- Stages 1 and 2 are the lighter stages of sleep.
- Stages 3 and 4 of non-REM sleep are the really deep, restorative stages of sleep.
- Rapid Eye Movement (REM) sleep, which is named because of these bizarre horizontal shuttling eye movements.”
“As you fall asleep, these stages will go into a battle for brain domination throughout the night. That cerebral wall between non-REM and REM is going to be won and lost every 90 minutes and then replayed every 90 minutes to create what we call a standard cycling architecture of sleep.”
- (Part I, 56:34) Non-REM sleep: “Different types of memory rely on different stages of sleep at different times of night, so you need sleep after learning to essentially hit the save button on your memories, so that you don’t forget. As long as you are getting say, the first five hours of the night, then it’s likely that you may have been able to protect those memories.
- Stage 2 Non-REM sleep happens most in the second half of the night. You not only need sleep after learning to save those memories, you also need sleep before learning to get your brain ready, in preparation to lay down new memories.”
Which type of sleep is more important?:
(Part I, 1:11:15) “Your brain has a different appetite for different types of sleep. Think of those different stages of sleep like a finger buffet, and at different times of the night, that buffet is going to be consumed more heavily in terms of the deep non-REM sleep phase. The window of preferential appetite for your brain when it comes to deep non-REM sleep is from 9pm until about 3am.
“From about 3am until about midday, then, the brain shifts in turns of its pattern if you let people just sleep it out. For people who like to go to bed very late and wake up very late, the buffet is going to get hit hard in terms of REM sleep devouring. I make that point that your brain has different taste sensitivities to non-REM and REM across the 24-hour clock face, because it means that if you’re short-changing your sleep by two hours, but you’re doing it by going to bed very early and waking up very early, then you’re going to be losing most of your REM sleep. Most of your REM sleep happens in the very late morning hours and if you’re already awake by 3 or 4am, you’re not getting the chance to get into those REM sleep-rich phases.”
REM Sleep vs. Deep Sleep:
(Part I, 1:18:00) “People will say, ‘How do I maximize my REM sleep?’ And I say, ‘Why do you want to maximize your REM sleep?’ And they’ll say, ‘That’s dream sleep, that’s the good stuff.’ Other people will say, ‘How do I get more deep sleep?’
“Answer: Mother Nature has found this equilibrium – don’t mess with it. It is the Davinci Code of sleep. Stick to it and you’re good to go.”
CONSEQUENCES OF POOR SLEEP
(Part I, 1:33:30) “Drowsy driving accounts for more accidents on our roads than either drugs or alcohol combined. When you are drunk, you typically react, but you react too late, so you do something but it’s not enough, and you crash. When you have a microsleep, you do nothing. That’s why drowsy driving is more fatal than drunk driving; because there’s no reaction. There is no application of brake, there’s no course correction of steering wheel angle, there is nothing. There is simply a car with no one in control and it’s a 2-ton missile on the freeway at 65mph, with no one in charge.”
(Part II, 29:01) “Social jet lag – where you essentially purge during the week and then binge on the weekend – is problematic, and not just because sleep doesn’t work like that and the studies show that that’s very deleterious to health. It’s because it also is terrible torture on your circadian biology. What happens is that you go to bed at one or midnight rather than 9, then wake up 10, 11 on a Saturday/Sunday. Come Sunday night, you’ve got to drag your body clock back by three hours to get into bed, and you repeat it the next weekend.”
Virility and Pregnancy:
(Part II, 20:11) “Men who are sleeping 5-6 hours a night:
- Have a level of testosterone which is that of someone ten years their senior. So insufficient sleep will age a man by a decade in terms of that critical aspect of wellness and virility.
- Have significantly smaller testicles than those men who are sleeping seven hours or more.
- Have fewer sperm and their sperm will have more deformities.
Women who are sleeping 5-6 hours a night:
- Have a 20% reduction in FSH (follicular stimulating hormone) which is a critical part of the reproductive pathway in terms of getting pregnant.
- Have a 30% higher rate of abnormal menstrual cycles.”
“If you put together a couple who is trying to conceive and that couple is on six hours of sleep, this is devastation.”
(Part I, 19:29) “One of the critical ingredients that they found that the glymphatic system washed away, was a sticky toxic protein called beta-amyloid. Beta-amyloid is probably one of the two core proteins that we know underly your risk for the development of Alzheimers. Ergo, if you’re not getting your sleep at night, you’re not getting that washing away of the toxic Alzheimers protein. Every night, then, you are building up more amyloid in the brain. If you keep doing that night after night, it’s like compounding interest on a loan. It’s just escalating your Alzheimer’s risk.”
(Part I, 38:25) “If you’re getting less than seven hours of sleep a night, you’re going against Alzheimer’s disease prevention and working well towards Alzheimer’s invitation. People will often say, ‘How much sleep do you get?’ I say I’ll give myself a non-negotiable eight hours sleep opportunity, and that’s not because I’m trying to practice what I preach. I don’t want to be some poster child for sleep. If you understood what I knew about sleep and all-cause mortality as well as most disease processes, you would realize that I am being nothing short of utterly selfish in my preservation of an eight hour sleep opportunity. I don’t want to die young, and I don’t want sickness and disease in my life.”
(Part I, 40:09) “Medicine has started to shift from a model of late-stage treatment to early-stage prevention. One of the best preventative actions that you can take on the basis of the science right now, is start to capitalize on your sleep at night.”
(Part I, 1:27:06) “A lot of people out there may be having this sleep machismo moment where they say, ‘I’m in my 50’s, I’m fit as a fiddle, my cognition is razor sharp, and I sleep five or six hours a night.’ We’ve got heads of state, for example, who are saying this, and it makes me sad because you can look at two other heads of state who were very vociferous about their proclamation of the uselessness of sleep: Margaret Thatcher and Ronald Reagan. Both of them were chest beaters when it came to insufficient sleep. They were very proud of saying that they only got four or five hours of sleep, that they were immune to the effects of insufficient sleep, that sleep was for the weak, and that you could sleep when you’re dead. I don’t think that it’s coincidental, now, looking back, that both of them went on to develop Alzheimer’s disease.”
(Part II, 44:00) A study by a colleague at the University of Chicago: “He looks at the relationship between sleep loss and cancer in mice. He took a group of mice, inoculated them with some cancer cells on their back, and then gave that cancer a one month period to grow. Half of those mice were allowed to sleep normally, the other half had their sleep restricted – not total deprivation – just limiting their sleep in the morning and the evening a little bit. At the end of that one month, for those under slept mice, the tumor was 200% larger. It was physically distorting the body. That cancer in those under slept mice had actually metastasized, which is just a fancy way of saying that it had breached the original origin and started to invade other organs, bones, and brain. When cancer becomes metastatic, that’s when we know things can get really dark and grim in terms of life expectancy.”
(Part III, 26:44) “One study looked at a group of individuals who were in mid- to later life and they had sleep apnea: snoring. (Sleep apnea is a devastating condition. If you snore or your partner tells you you snore, please go and see your doctor, get a sleep test, and get on sleep apnea treatment.) They gave them a CPAP treatment which is this sort of face mask to push the airway open so that you don’t snore and you don’t go without oxygen. About half of those individuals were compliant with the treatment, and half weren’t. Those individuals who complied to the treatment and started sleeping better ended up staving off the onslaught of Alzheimer’s disease by about ten years. This is a causal demonstration that if you course correct sleep, you can actually modify your dementia probability risk.”
(Part III, 33:55) “You typically see far higher rates of diabetes in people who have untreated sleep apnea, and when you treat them, you see their diabetic profile improve markedly. You also see that they start eating less, their choices of food are better, and they are far more likely to be physically active.”
FOOD AND DIET
(Part III, 35:00) “Two appetite hormones that regulate food intake:
- Leptin is the satiety signal – it tells your brain that you are full, you don’t need to eat anymore, you’re satisfied with your food.
- Ghrelin is the hunger signal. It essentially says, ‘No, you’re not satisfied with your food, you want to eat more.
“When you start short-sleeping people four, five, six hours a night for one week, these appetite hormones go in opposite directions in ways that you wish they didn’t. The leptin signal that’s saying, ‘you’re full’, gets turned down. Instead, ghrelin is actually ramped up, so you start to feel unsatisfied by your food, and you will eat more. You downgrade this red flag of satiety and you upgrade the signal of hunger, which then leads to an increase in your caloric intake. People who sleep six hours a night during the week will typically eat about 300 extra calories during the day (70,000 calories each year; 10 pounds of additional mass).”
(Part III, 40:00) “It’s not just that you overeat when you are under slept, which you do, and if you pull the all-nighter you’ll typically eat about 450 more calories than when you’re well rested. It’s also the profile of food that you eat. If you give people a food buffet and you say, ‘Eat whatever you want, it’s up to you.’ What you find is that, not only do you eat more, people will eat more from the heavy-hitting starchy carbohydrates together with simple sugars, like pizza, cookies, ice cream, and they stay away from things like macadamia nuts, avocado, and leafy greens.”
(Part II, 18:51) “A great study looked at the efficiency of dieting when you are under slept, and they found that your diet is all for nothing if you’re not sleeping well, because when you are under slept (six hours or less), 70% of the weight that you lose will come from lean muscle mass and not fat. In other words, your body will ruthlessly hold on to its fat when you are under slept and not give it away. So you’re losing the thing that you want to keep, which is beautiful muscle definition, and you’re holding onto the one thing that you’re trying to get rid of, which is the blubbery fat.”
Eating Before Bed:
(Episode #58 15:37) “The optimal time to stop eating before bed is about three hours.
- When you lie down, you’re more likely to get acid reflux; more likely to have digestive issues.
- You need to drop your core body temperature by about two or three degrees Fahrenheit to initiate sleep and then to stay asleep. If you’re fueling yourself with simple carbs right before bed, you will actually see a slight increase in core body temperature. So the advice is, don’t go to bed too full, don’t go to bed too hungry. If you do feel as though you ate earlier in the evening and you just need something to take the edge off, try to stay away from simple carbs (those will get translated into energy and ultimately a heat index) and lean more towards protein.”
Hours of Sleep Needed for Teenagers:
(Part II, 1:07:50) “89% of 18 year-olds in the U.S. are not getting sufficient sleep. Even when you’re 16, 17, 18, you’re still needing 9-10 hours of sleep because your brain doesn’t finish developing until it’s about 25.
“If you ask parents, ‘Do you think your teenager is getting sufficient sleep?’ 72% of them will say yes, yet only 11% are getting the necessary sleep, so there is a mismatch here between the parental and child sleep equation. What that also leads to, then, because parents believe that their kids are getting enough sleep, is a parent-to-child transmission of sleep neglect, ie the pulling the covers off on the weekend, when these kids are sleeping in.
“These kids are sleeping in for two reasons:
- Naturally, their biological circadian rhythm moves forward in time, so they want to go to bed later and wake up later. It’s not their choice; it’s biological. It’s hard-wired. For age 16, 17 you’re looking at a 10-hour period from somewhere between 10-midnight depending on their chronotype, to then sleeping in until between 8:30-10:30 the following morning. The reason that actually is still too early, is because that would be what would naturally happen if you were to let them sleep like that every single night of the seven days of the week, but we don’t.
- During the five days of the school week, we are getting them up way too early. You can even put them to bed at 9 or 10, and say, ‘Sleep,’ but they can’t, biologically. They won’t be sleeping as well during the week, so at the weekend they’re trying to sleep off a chronic debt that we’ve saddled them with during the week. No wonder they’ve got such a sleep pressure that is forcing them to try and sleep until 1 or 2 in the afternoon. Then we chastise them. We say, ‘You’re lazy, get out of bed, you’re wasting the day,’ but it’s not their fault.”
School Start Times:
(Part II, 1:05:06) “We will look back in 20 years with shame that we were having schools start at 7:30 in the morning. For these schools, buses will start leaving at 5:30am. That means some kids are having to wake up at 5:15, 5:00, or even earlier, which in my mind is lunacy. The shame will be present when we consider the impact, and we already know the impact from the studies when we delay school start times. What we see is that:
- Academic grades improve
- Truancy rates decrease
- Behavioral problems and psychiatric problems decrease
- Number of people who drop out of school and drop out of certain classes decrease
- Life expectancy of students increases
“Life expectancy increases because of car crashes. There’s a great study in Wyoming: they shifted their school start time from 7:35am to 8:55am. In that following year, they looked at this narrow age range of 16-18 years old, and there was a 70% drop in car crashes. So when sleep is abundant, minds will flourish, and if our goal as educators truly is to educate, and not risk lives in the process, then I fear that we are failing our children in a quite spectacular manner with this incessant model of early school start times.”
(Part II, 1:11:45) “Back in the 60’s, schools were starting around 9 o’clock. As we marched on in terms of ‘development in society in the US’, that time has gone back and back to earlier and earlier start times. It’s been squeezed by the vice grips of work schedules where parents are having to work longer hours and commute longer hours. They have to leave the house ever earlier, so they have to put the kids in school ever earlier. Many of these kids are just sitting there, un-absorbent, like a water-logged sponge. They’re not going to be taking up information. If you look at the data regarding delayed school start times, overall, GPA and SAT scores rocket up; they all improve.
“Which classes get the biggest benefit in terms of the grade improvement? It tends to be not the classes in the afternoon, where they are finally awake because of their circadian rhythm. It’s the classes in the morning, where before, those classes would be starting at 8:00. When you push them to 9:30, they’re doing much better in those classes, and it reaffirms the case that the hit that is going on in terms of the amnesiac impact that early school start times is having, is really in those morning hours, when the brain is not designed to be awake, and it’s certainly not designed to be receiving an education. It’s designed to be asleep, preparing itself for education.”
(Part II, 1:14:07) “You absolutely do learn more efficiently when you have had sufficient sleep, so it’s a forcing function. It’s like zipping a file. The amount of information that can be stored is much greater. But let’s say that to do this staggered system with the bus unions and to make it work out with parents and work schedules, it’s going to require more money to figure this out. It turns out that some of that can be cost savings on the back end because kids get released later.
“There is a time when kids get kicked out of school if they start early, which is this kind of criminal, bewitching hour where the kids are out of school but the parents are not home yet from work. That’s where you see a lot of juvenile crime happen, which is in that twilight hour between the 3-4pm period when they’re out of school to the 6-7pm period where the parents are finally there and they get home. If you look at the cost of that criminal impact of activity in those hours, and then you say, If we were to start schools later, kids get out later, we limit the window of criminal opportunity. The cost savings comes back around and pays for itself.”
(Part II, 1:17:50) Peter says, “Let’s assume you don’t have that luxury. School starts at 8:10 and gets out at 3:40. What can parents do right now to help the kids get as much sleep as possible?”
(Part II, 1:24:50) “Try and limit technology. I know that it’s hard because the genie feels like it’s out of the bottle and it’s not going back any time soon, but to try and maximize their sleep in the face of early school start times, taking the technology out of the bedroom is probably the single best thing that you can try and do.”
- Melatonin – We are a dark-deprived society in this modern era, and we need darkness at night to allow the release of a hormone called melatonin. As melatonin rises, it will help time the onset of your sleep. There are great studies being done where, say you use an iPad for an hour before bed. You get about a 50% drop in the melatonin that’s released, so you lose 50% of the signal of sleep timing.
- Television – It has another mental impact, especially if you’re watching it in bed. That’s not a good idea because then your brain associates your bedroom as the place of being awake and watching television, not the place of sleep, and when you start to form those maladaptive associations, it can be a trigger of insomnia and anxiety. You should only use the bed for sleep and intimacy – that’s it.
- (Part II, 1:21:15) Sleep Procrastination – “There was a survey done that demonstrated that well over 80% of teenagers admit to waking up during the night to check their phones and check social media. So you’ve got this dependency that is causing this alertness spike to wake you up, and that’s a habit that once it builds, it’s quite difficult to break.
- (Part II, 1:22:25) “Anticipatory Anxiety – Many people have had that experience where you have an early morning flight, and you’ve got to wake up at 5:30am and you know it. You set the alarm, and you wake up at 5:28 and you are awake like a bolt. That’s an extreme example. A weaker version happens with our phones because most people, the first thing that they do when they wake up in the morning, is swipe and unlock this world of anxiety that just comes flooding in through their phone – emails, texts, social media. You are essentially training your brain to anticipate that wave of anxiety every morning. When you embed that anticipatory expectation in the morning, the amount of deep sleep that you get at night is less. You end up sleeping in a shallow state, and you don’t get the same amount of deep sleep.”
(Part I, 58:54) “Sleep is emotional first-aid. Bottom line, period. In young teenagers, one of the strongest predictors of suicidal ideation (thoughts of taking their own life), strongest predictors of suicide attempts, and tragically, a very strong predictor of suicide completion, is insufficient sleep and sleep fragmentation. What we’ve been finding is that it’s REM sleep that seems to provide essentially a form of overnight therapy, and it’s REM sleep that resets or re-calibrates the emotional networks in the brain.”
(Part I, 1:01:57) “You often see a parent with a child and the child is crying and they say, ‘Well they just didn’t sleep well last night.’ As if there’s this universal parental knowledge that bad sleep the night before equals bad mood and emotional reactivity the next day. What’s striking, when you look at the data, somewhere between infancy and even now, childhood, not only do we abandon the notion that sleep is absolutely essential and non-negotiable, but we start to stigmatize it with this label of laziness – that you’re slothful, or that you’re child is slothful for getting sufficient sleep.”
(Part III, 44:28) “If you look at employees who are sleeping six hours or less:
- Those employees will select less challenging problems. You give them a range of problems and they typically will choose listening to voice messages or doing email, rather than digging in to hard project work.
- Of the problems that they do select, they end up producing fewer creative solutions to those problems, and that’s an issue because it’s supposed to be creativity and ingenuity that’s driving businesses forward.
- Social Loafing – Riding the coattails of other people’s hard work. When under slept employees are working in groups or teams, they slack off, and they just let other people work.
- The less and less sleep that an employee has had, the more and more deviant and unethical they became. For example, they start to falsify data in spread sheets, they start to claim the work of other people, even falsify reimbursement claims.
- The less sleep that that CEO had had from one night to the next, the less inspiring and charismatic that their employees rated that business leader from one day to the next. Even though they knew nothing about the sleep of that leader, it was evidential in their behavior.”
(Part II, 35:55) “Recently the World Health Organization decided to classify any form of nighttime shift work as a probable carcinogen. The proof of evidence that is required by the World Health Organization to make such a statement usually has to be astronomical.”
THE STRUGGLE WITH SLEEP
(Part III, 26:10) “Sleep is not like the bank. You cannot accumulate a debt and then hope to pay it off at a later point in time. That’s why that binging on the weekend doesn’t work. So once you’ve gone without sleep, whatever has happened during that time when you are under slept, doesn’t seem to be reversible. However, that doesn’t mean that from this point forward, it’s a waste of time to start sleeping better.”
Reading Before Bed:
(Part II, 1:27:15) “Patients will say, “I’m sitting on the couch watching television and I’m falling asleep, and then I get into bed and I’m wide awake and I don’t know why.” It’s because your brain has learned the connection between your bedroom being a trigger for wakefulness because wakefulness is what you do there. What you need to do is break that association and get up after 20 minutes, go to a different room in dim light and read a book elsewhere. And then, only where you’re sleepy – and there’s no time limit for this – should you return to bed. The analogy would be this: you would never sit at a dinner table waiting to get hungry, so why do you we lie in bed waiting to get sleepy?”
(Part II, 1:28:53) “Light, in general, is not great because it will stamp the brakes on melatonin and it will stop releasing it. Your brain is fooled into thinking it’s still daytime, even though it’s actually nighttime. If it’s an LED light, it’s usually enriched in the blue, sort of low frequency of the visible light spectrum and it’s the most harmful to melatonin.
“If there’s a better form of light, it’s the red and yellow – the warm colors. Even if it’s just going back to a classic light bulb which typically is warmer in color and low in wattage. That’s your best light for reading.”
(Part II, 1:30:44) “They used to leave these fluorescent light bulbs on in the NICU (Neonatal Intensive Care Unit) for premature babies all of the time. At that point, even though the circadian rhythm isn’t especially robust in infants, they still need that signal of light and dark. When they regularized light in the NICU – when they gave back darkness at night and gave strong light during the day – the infants started to sleep better and three things happened:
- You saw about a 50% improvement in oxygen saturation in those infants.
- They put more weight on within the time period, because they were sleeping more regularly.
- They left the NICU somewhere between 2- 2 1/2 weeks earlier.”
(Part II, 1:32:10) “The reverse experiment was done where they took a group of people who said they can’t get sleepy until about 11pm and were only getting 6-6.5 hours of sleep. They took that group of people to the Sierras – this beautiful mountain range with no electricity and no access to artificial light.
“Here’s what happened:
- These individuals started going to bed around 9 o’clock, and this wasn’t necessarily because they didn’t have anything to do.
- They rated themselves as feeling sleepier earlier. Why? Because they were getting the signal of darkness at the natural time.
- They went from being ardent about the fact that they were only 6.5 hour sleepers and that’s all they needed, to then sleeping a little bit more than nine hours.
“I think this point about going to bed at 9pm is a really important one. Have you ever thought about what the term midnight actually means? It means middle of the night. Now, with the perversity of the industrialized civilization, midnight means it’s the last time to send a few emails, whereas if you look at hunter-gatherer tribes, who’s way of life hasn’t changed for thousands of years, and you ask how do they sleep, they typically go to bed an hour and a half to two hours after sundown, so around 8:30, 9:00. They usually get about 7, 7.5 hours of sleep at night, and then they have a siesta-like nap in the afternoon to make it up to about a total of nine hours.”
(Part II, 1:53:20) “I’m not anti-pharmacology by any means. If we had a good sleeping pill, I would embrace it and I would recommend it, but right now, the sleeping pills don’t produce naturalistic sleep. They’ve been associated with a significantly higher risk of death, and also, significantly higher risk of cancer.”
(Part II, 1:55:40) Peter Attia says, “My friend says to me, ‘By the way, that Ambien crap that you take a couple times a month, you know that’s not sleep right? And I said, ‘What do you mean it’s not sleep? I’m out.’ He said, ‘You’re confusing lack of consciousness and sleep. If I took a baseball bat and hit you on the head, I could render you completely unconscious laying on the floor for eight hours. Do you think, in any way, that mimics the restorative process of sleep? Not even close, so think of Ambien as a chemical baseball bat to the head.'”