POOR SLEEP Is Killing You! - DO THIS To Optimize It TODAY! | Matthew Walker & Lewis Howes

Why is there such mortality risk caused by insufficient sleep? And what we know is that a lack of sleep and typically getting certainly less than six hours of sleep is associated with a high risk of cardiovascular disease, high risk of diabetes, high risk of stroke. And then downstairs in the body, we know that there is links between a lack of sleep and certain forms of cancer. If I were to take you and limit you to, let's say, four or five hours of sleep for one week, your blood sugar levels would be so disrupted that your doctor would classify you as being pre diabetic. So that's not a lifetime, that's just one week.

I think you gotta have a dream.

The school of greatness, really.

Yeah. Please welcome Lewis Howes. As a former athlete, as someone who's always wanted to perform at high levels in business and sports and just have a great life, I've been obsessed with the topic of sleep and I've been obsessed with creating sleep sanctuaries. You know, figuring out what plants you put in your room when you sleep, what temperature should it be, the blackout shades, like all this stuff. I've been obsessed with this. And I'd love to start with asking the question about if we sleep poorly, how does this impact our brain? If we just sleep poorly one night or over and over and over again, how does that impact the brain chemistry?

Yeah. So I think, firstly, in response to the general question, sleep is probably the single most effective thing that you can do to reset both your brain, but also your body health, of course, as well. And I don't say that flippantly against the notions of diet and exercise, of course, both of those are fundamentally critical. But if I were to take you, Louis, and I were to deprive you of sleep for 24 hours, deprive you of food for 24 hours, or deprive you of even water or exercise for 24 hours. And then I were to map the brain and body impairment that you would suffer after each one of those four hands down by a country mile, a lack of sleep will implode your brain and body far more significantly. The only one I would probably lose out on is oxygen. At that point, I'll give it up. You know, sleep will take the silver medal, oxygen definitely gets the gold. But thereafter, sleep seems to be paramount over sleep.

Food and water, sleep is the most important thing.

I would. Yeah. You know, I used to say that sleep was the third pillar of good health, alongside diet and exercise. But I think the evidence has suggested that I was utterly wrong, that sleep, in fact, is the foundation on which those two other things sit. And you can do wonderful things in those two main domains. But if you're not getting sufficient sleep, those things tend to be far more futile as a consequence.

And so what is sufficient sleep then?

So right now we Recommend Somewhere between 7 to 9 hours for the average adult. Once we know that you go below seven hours of sleep, we can start to measure objective impairments in your brain and your body. And in fact, the number of people who can survive on less than six hours of sleep without showing any impairment, rounded to a whole number and expressed as a percent of the population, is.

Zero without any impairment, what does that mean?

So if I can measure lots of different operations of your brain, let's say your cognition, your attention, your learning and memory, also your moods and your emotions and your anxiety, or downstairs in the body, I can measure aspects of your cardiovascular system or your blood pressure, or I could measure your immune system or your metabolic system, how it's regulating your blood sugar and your glucose. I can measure this sort of pinwheel, this kaleidoscope of health metrics on Lewis Howes. And then I can see, when I keep dialing you back with less and less sleep, at what point do I see at least one of those things demonstrating a breaking point? And it's very rare for us to be able to find any individual who can go below six hours of sleep and not show some kind of impairment. And a great, even frightening demonstration of this study took a group of perfectly healthy individuals and they limited them to six hours of sleep a night for one week. And then they measured the change in their gene activity profile relative to when those same individuals were getting a full eight hour night of sleep.

And what happened?

And there were two critical findings. The first was that a sizable and significant 711 genes were distorted in their activity, caused by that one week of short sleep. And that's, you know, in some ways, I think about this, Louis, because it's reality. We know that almost a third of the population is trying to survive on six hours of sleep or less. So it's not just total sleep deprivation, which doesn't happen very frequently. This is a common occurrence. What I found most interesting was that about half of those genes were actually increased in their activity. The other half were decreased. Now, those genes that were suppressed were genes associated with your immune system. So you became immune compromised or immune deficient. Those genes that were increased in their activity, or what we call overexpressed, were genes associated with the promotion of tumors, genes that were associated with cardiovascular disease and Stress and genes that were associated with long term chronic inflammation within the body. And I, I make that point just because, you know, many people, I think, have this concern about things such as genetically modified embryos or even genetically modified food, but when we don't get sufficient sleep, we are unwittingly performing a genetic manipulation on ourselves. You know, if we don't let our kids get the sleep that they need, then we're inflicting a similar genetic engineering experiment on them as well.

Wow, this is crazy. So what if you've been sleeping less than six hours a night for years? What is that saying to your genes? And is there a way to recover the gene damage and reverse and go back to a healthy genes, healthy body, healthy life?

So firstly, we know that short sleep duration, so using that sweet spot, and we can speak about oversleeping or excess sleep, because that, I think that's an interesting part that hasn't been spoken about too much. But using that recommended CDC amount of seven to nine hours of sleep, there is a simple fact, firstly, across the lifespan, which is the shorter your sleep, the shorter your life, that short sleep predicts all cause mortality. But then we can dig a little bit deeper and start to sort of ask exactly what is going on? Why is there such mortality risk caused by insufficient sleep? And what we know is that a lack of sleep and typically getting certainly less than six hours of sleep is associated with a high risk of cardiovascular disease, high risk of diabetes, high risk of stroke, high risk of dementia. And I would love to double click on that and go into the Alzheimer's disease risk because that now evidence is very, very strong. And then downstairs in the body we know that there is links between a lack of sleep and certain forms of cancer after. If I were to take you and limit you to, let's say four or five hours of sleep for one week, your blood sugar levels would be so disrupted that your doctor would classify you as being pre diabetic.

Oh my goodness.

So that's not a lifetime, that's just one week. And there's an even more interesting experiment that I, I think speaks to the subtlety of this because there is the largest sleep study that's ever been conducted and it happens actually to around 1.6 billion people across 70 countries twice a year. And it's called daylight savings time now in the spring when we lose just one hour of sleep opportunity. Firstly, what we've seen is that there seems to be a 24% increase in relative heart attack risk the next day, which stuns me and what's fascinating, in the fall, in the autumn, when we gain an hour of sleep, there's a 21% reduction in heart attacks. So it's bidirectional. And that's just one hour of sleep. And you see there was some great recent data, you see a very similar profile regarding that daylight saving shift for road traffic accidents on our streets.

I've heard about this.

Tragically, suicide rates as well. And then even more recently, what we discovered is that during that springtime shift when you lose an hour of sleep, the sentencing of, of federal judges is significantly harsher because their mood and their emotion is that much worse because of that one hour of lost sleep that they dole out harsher sentences. So, you know, we can walk, you know, you can ask the question, what about a lifetime? We don't even have to ask about a lifetime of short sleep. We can ask about these really, you know, one week of short sleep or even one night of one hour of lost sleep. And I think that's how fragile our brains and our bodies are to this thing called a lack of sleep. And you could then ask, well, you know, why are we so sensitive? Because I can go without food for 24 hours and I can go without water for 24 hours. You know, I'm still not too bad, I'm in fairly decent shape. Why is sleep the exception to that rule? And the answer seems to be this. Human beings are the only species that will deliberately deprive themselves of sleep for no apparent good reason.

Why is that?

And it was such a unique thing. And what that means is that Mother Nature through the course of evolution, because no other species does this without real need for survival. And I can speak about some of the exceptions, but here human beings are strange like this. In other words, Mother Nature hasn't have to face the challenge of coming up with a solution called sleep deprivation, because she's never faced it in the course of evolution. And so there is no safety net in place here. And that's why we think human beings implode so quickly and thoroughly, mentally, cognitively and physically caused by insufficient sleep.

And why do you think, why is the, why are the majority of people bad at getting good sleep? Is it what is it we're distracted? Is it we think we need to be doing more? Is we're stressed and worried about the past and the future? Is it you know what, we just want to work harder? What is the main cause of why we get poor sleep?

It's such a fundamental question. And in some ways it's all of the above. Plus. So I think the first, and I've thought about this a great deal, why are we suffering this global sleep loss epidemic that we're under right now? I think the first thing is that unfortunately sleep has an image problem that, you know, the PR agent for sleep should be fired because we, we associate sufficient sleep with this concept of being lazy, of being slothful. And that's a terrible disservice to this thing called sleep. And it is very different to things like diet and exercise. You know, I think a lot of people like to virtue signal with, you know, what they eat. And they certainly are very proud to tell you, you know, I work out five times a week. I'm in the gym at this time of morning. And, you know, all of which I think are great and to be applauded and supported. But we have the very opposite. We have this almost, you know, well, we, we don't some, some niches of society have this sleep machismo attitude. You know, this kind of you can sleep when you're dead mentality, which by the way, based on the evidence, is mortally unwise. Yeah. It will lead to both a shorter life and a life that is significantly less healthy. So I think the first thing is we need to change our cultural appreciation of sleep from something that is a waste of time to something that in fact is an incredible investment. It is probably the very best and the most freely available democratic and painless and health insurance policy that I could ever imagine. I think the next thing is the way that we work in society. We are working for longer hours. And before the pandemic, people were commuting increasingly longer amounts of time. What that meant was that people were leaving the house earlier, they were arriving home later, and no one wants to shortchange time with family or Netflix or whatever. It is your poison. And so the one thing that has become squeezed like vice grips in the middle of the night is this thing called a sufficient bout of slumber. But then there are plenty of people who give themselves the opportunity to get enough sleep, but they can't obtain it. And that is where things such as insomnia or sleep disorders, things like snoring come into play and you touch up. And I know that you've spoken and I'm so grateful for what you've done. Regarding discussions of mental health, we know that one of the principal roadblocks to getting this thing called a good night of sleep is anxiety.

Stress, worry, anxiety, regret, all those things.

Yep.

Resentment, holding on to all that stuff.

It is that is toxic to sleep. You're absolutely right. And in fact, anxiety and physiological stress is our principal model for the explanation of insomnia. Right now. It's not the only cause, but it seems to be one of the principal causes. And in modern society, it's become so easy. And I'm not finger wagging, I suffer. You know, I'm just as guilty. We are constantly on reception, but rarely do we do reflection. And unfortunately, the time when most of us do reflection is when we turn off the light and our head hits the pillow. And that's the last time. Oh, you know, because I don't know about you, Louis, but, you know, at night in the dark, thoughts are not the same thing. You know, concerns become twice as big or you 10x the size of concerns. I start to worry, I ruminate, I. I catastrophize. Yet in the light of day, those things seem very different. And so we can speak about sleep tips perhaps later on, but certainly getting right with your emotions and your anxiety is key to good sleep. And that's one of the things that prevents sleep. I also think that there is an issue at the public health level. You know, we've had in many first world nations wonderful government mandates regarding health, regarding drink driving, regarding, you know, safe sex, regarding drugs and alcohol and even food, and even inactivity and sitting. And when was the last time you heard of a first world nation provide a public health message and memorandum regarding sleep?

Never.

And I don't remember one either. So from every level at, you know, at a public health, global, you know, government level, down to a workplace level, you know, we lord the airport warrior who's flown through four different time zones in the past three days. They were on email at 2, and then they're back in the office at 6. You know, we. So we need to.

We celebrated those people.

We did. You know, and the funny thing, by the way, is that after about 20 hours of being awake straight, you are as cognitively impaired as you would be if you were legally drunk. Now, I would never, you know, as a CEO, say, I have got this fantastic team of people. They're drunk all of the time. But we do say, I've got this fantastic group of people. They just are at it all hours. They are dedicated, they're always working. You know, they spend minimal time sleeping. They're just all out. They love this project, but we've got this strange mentality. And then I think it comes down to, you know, even within schools, we've got this incessant model of early School start times.

And super early, isn't it?

It's, it's got to be there, what.

6:30 or 7 or something, right?

37, 7:30. And that data is actually very powerful. What we found is that when we delay school start times, first academic grades increase.

Wow.

Truancy rates decrease, psychological and psychiatric issues decrease. But then what we also discovered is that the life expectancy of students increased. And you may be thinking, well hang on a sec, you know, how do you, how do you measure that? And the leading cause of death in teenagers 16 to 18 is actually not suicide. That's second, it's road traffic accidents.

Really.

And here sleep matters enormously. And I'll give you one example. It was in Teton county in Wyoming. They delayed their school start times from 7:30 in the morning to 8:55. By the way, what are we doing trying to educate our children at 7:30 in the morning?

I can't think. Yeah, I mean I remember being in school and being every day was hard for me. Every day I was tired every day I was hard to focus or I'd be irritable or wanted to like you know, jittery or something. But it was like so hard to focus. And then you're at lunchtime and then I eat and I'm tired again afterwards and you want me to focus and pay attention at a desk. It's like it doesn't work like that for me especially. I have no sleep or very well.

For any, any you know, sort of developing brain. It doesn't work like that. And for some people to make a 7:30am start time, school buses will begin leaving at 6:00 or 5:30 in the morning. That means that some kids are having to wake up at 5, 5:15. This is lunacy. And what we've understood from the academic grades and I'll come back to the car accidents in a second. When sleep is abundant, minds flourish. And when it's not, they don't. And what we've discovered with the road traffic accident in Teton county, when they made that shift, the only thing more remarkable than the extra one hour of sleep that those kids reported getting was the reduction in car crashes. The following year there was a 70% drop in vehicle accidents.

Wow.

And to put that in context, you know, the advent of ABS technology, anti lock brake systems that dropped accident rates by 20 to 25% and it was deemed a revolution. Here is the simple fact of getting enough sleep that will drop accident rates by 70%. So you know, I need to get off my Soapbox. But what I would say is this. I think if our goal as educators is to educate and not risk lives in the process, then we are failing our children in the most spectacular manner with this incessant model of early school start times.

Is anyone listening to this that you've been speaking about this too? And they're actually adopting this new model, whether it be work time or school time, or just, you know, integrating this. Do you know systems that are integrating this?

There have been some. And I think I. I've tried to do this in the education domain. I've tried to do this within medicine because the way that we train residents is. Is almost inhumane. Actually. It's. It's not almost. It absolutely is inhumane. And the statistics there are stunning as well. And then I've tried to do it in the workplace too, because I do a lot of speaking events at sort of Fortune 500 companies. And at first I think I took the wrong approach where I was really speaking a little bit more about sort of the compassionate approach. You know, why it's good and kind for people to gift them more sleep. Because I see sleep as a biological necessity. And if it's a biological necessity, then I think it's a civil necessity. And if it's a civil necessity, sleep is a civil right. But what I would say is that that wasn't particularly well received. You know, I'd go into business companies and say, your employees, you know, they're desperate for more sleep, they will be happier and healthier. Or I would speak about medicine and I would speak about, you know, what it was doing to the patients and the harm, and it would fall on deaf ears. What I then realized is that if you're going to change large organizations, you have to speak in their currency, which is money. Money.

Yeah, you need to.

And then I would describe the medical malpractice lawsuits that would commonly cost savings within medicine firstly. And then administration started to change the tune because before that, you know, there was almost this old boys network in medicine where we went through residency and it's almost a hazing. And despite armed with incredible data to the contrary, I think the mentality 10 years ago when I started trying to do that was my mind's made up. Don't confuse me with the evidence.

Crazy. Why? It's because they went through that themselves. And so they want to pay it back or something.

I think so. I think there's some of that.

I went through hell, so everyone else has to go through hell.

Yeah, right. It's a rite of passage. You know, if you are tough enough, you'll make it through through. It's kind of like boot camp, which I don't think we need to do anymore. And then within business, you could describe, you know, the Rand Corporation did an independent survey a couple of years ago and what they found was that insufficient sleep will cost most nations about 2% of their GDP of their gross domestic product. So here in the US that number was $411 billion of lost productivity due to insufficient sleep. In Japan, it was $130 billion. My home country, the UK was over $50 billion. So if I could solve the sleep loss crisis within the workplace, I could almost double the budget for education in the US Or I could halve the healthcare deficit. So when you speak about money, then people start to listen. So that's how I've tried to communicate. And I don't think I'm a particularly good communicator. And I've been sometimes bull in a china shop as I probably have been for the first however long we've been talking. But it's just because I'm so, you know, I'm just desperately passionate about this thing called sleep. And some years ago, before I started trying to, I wrote a book and then I've been doing podcasts. Sleep was the neglected stepsister in the health conversation of today. It was a second citizen. And I was so sad to see the disease, the sickness, the harm, the lack of productivity, the impact on education that a lack of sleep was having. And I think I just came out probably a little too strong, you know, sort of sleep or else dot, dot, dot.

Yeah, I'm curious. Oh, go ahead.

Yeah, no, no, sorry, please.

I'm curious. What is the. Has there been research or studies done on if someone who has a horrible diet, they eat horrible, they smoke, they drink occasionally, but they get eight hours of sleep versus someone who gets five hours of sleep but works out hard every day. Eats perfect, clean, vegan, whatever the perfect clean diet is for them. Don't smoke, don't drink. I wonder who has more susceptibility to diseases and cancers and poor health and what which problems are each case more prone to have perfect eating but not, not proper, half the amount of sleep four or five hours a night, but you're taking care of physically, you're taking care of spiritually and nutrition versus you sleep perfect. Maybe you won't be able to sleep perfect if you're eating that bad, but you sleep eight hours a night, nine hours a night, but you're eating horrible who has it worse off?

So firstly, I think you should be a sleep scientist because it's a fantastic question, it's a great study, and it's an incredibly complex but important study to do. The first answer is that no one has actually done that type of experiment. We've done a diluted version, a kind of, you know, diet, light L I T E version of it, which is we look at sleep and we ask what is it in terms of the mortality risk and the health consequence risk when you're not getting sufficient sleep? And then we take all of those other factors that you've described, smoking history, diet history, mental health history, et cetera, et cetera, and we add those as additional factors into the analysis and we absorb them and control for them so that we can say, independent of those things or in spite or in the face of those things, sleep still carries a significant vote in determining your mortality, your rate, your date of expiration, as it were. So that's the only evidence that we have right now where you can at least control for those. But we haven't done what you're describing, which is the much more elegant, smart thing to do, which is, you know, can we put them sort of almost in a Coke, Pepsi, Dr. Challenge, kind of Dr. Pepper challenge phase and see which one wins out? You know, diet, exercise or sleep, when those two other things are held constant, but you manipulate one of those, then hold the other two constant and manipulate one of lovely experiment, love to do it. It's not been done.

So we don't know. What would your hypothesis be?

My suspicion is that sleep will still probably carry a larger influence than those two other factors. Now, there's a lot of assumptions I'm making there, but I, I'll give you another quick example, a study done back in the 1980s which will probably never be repeated because of the moral and ethical issues. They took a group of rats and what they found after sleep depriving the rats was that rats will die as quickly from sleep deprivation as they will from food deprivation. So sleep is that essential. Those rats were dying usually within 20 days. So sleep seems to have a deathly consequence to it. What was also fascinating, however, is that they then, and maybe I'll back up a little bit, human beings and most mammalian species will have two main types of sleep, what we call non rapid eye movement sleep or non REM sleep, and rapid eye movement sleep or dream sleep. And what they found was that total sleep deprivation will absolutely kill a rat if you just selectively deprive the rat of either deep non REM sleep or REM sleep or dream sleep. They found that the rats would still die of either one of those two. So both of those types of sleep are essential. But rats were dying almost as quickly from dream sleep deprivation as they would from total deprivation. Well, they died within about 40 days, whilst the rats who were deprived of deep non REM sleep, they died after about 60 days. So, you know, we can almost then, not that I would wish to pit the different types of sleep head to head and ask which is more important. Now, I should say all stages of sleep are critical. That's probably the one of the biggest messages that we've learned. Different types of sleep do different things for your brain and your body at different times of night. All of them are important. But it seems as though if you want to ask the question of death risk, dream sleep may be more important than deep sleep on the consequence basis of how quickly you die. But you need all of them. Bad things happen when you don't get any one of them.

Gotcha. Can you talk about dreams and the importance of dreams?

Yeah, we've done quite a lot of work in this area and the belief maybe 20 or 30 years ago was that dreams were just an epiphenomenon, they were just a byproduct. And so the analogy would be, you know, think of the light bulbs that I think I can see behind you in that lovely background, you know, when you, when you create this apparatus called a light bulb to produce this thing called light, in the same way that the brain has been created to produce this thing called dream sleep, called REM sleep, when you create light in that way with the light bulb, you also produce this thing called heat. It was never the purpose of the light bulb, it's just what happens when you create light in that way. And the belief was the same thing for dreaming, that when you create this thing called REM sleep, which serves lots of different functions, one of the conscious spinoffs, one of the byproducts is this thing called dreaming. And that never made sense to me for the simple reason which is this, when we are dreaming, it is more consciously, energetically demanding than not dreaming, is my assumption from a brain based perspective. And any time Mother Nature burns the most valuable unit in your body, when which is called an ATP molecule, an energy molecule, then it usually has some evolutionary advantage to it. In other words, if dreaming is metabolically more active and you could have REM sleep without dreaming, but she still added dreaming atop of REM sleep, then it must serve some benefit and we've now discovered that it serves at least two vital functions, really. The first is that dream sleep provides a form of almost overnight therapy, that dream sleep is emotional first aid.

Interesting.

And it's during dream sleep at night that your brain takes those difficult emotionally charged experiences, sometimes even traumatic memories. And it acts like a nocturnal soothing balm. And it just takes the sharp edges off those painful, difficult experiences so that you come back the next day and you feel better about those experiences. And in that way, it's not time that heals all wounds, it's time during dream sleep that provides emotional convalescence, as it were. And it's not just dream sleep, it's also even what you dream about, not just that you dream. In other words, I'm talking about your dream content being important because there was a study done several years ago and they looked at people going through a really tough time, a traumatic experience, which is a really painful and bitter divorce. And at the time when that was happening, they were recording their dreams. And then they tracked those individuals for a year and one year later, about half of them had clinical resolution to their depression and the other half did not. And then they went back and they separated the dreams of those two different groups. And what they found is that those people who were dreaming, but not dreaming about the emotional events themselves, they didn't get clinical resolution one year later. Those people who were dreaming but dreaming of the event, they got the clinical resolution. So in other words, dreaming is necessary, but it's not sufficient. You need to be dreaming of what those events are to process those.

How do we influence dream? How do we influence dreaming what we want to dream and not nightmares?

That's right. Yeah. Well, this moves us into the territory of what we call lucid dreaming.

Yes.

And for most people, lucid dreaming from within my field, within the scientific field, is actually a more simple definition. It's simply the moment that you become aware that you're dreaming, that you're dream whilst you're dreaming. Correct.

Does that exert more energy when having the dream creates. Exerts more energy. If you're conscious and aware while dreaming, is that another level of energy that you're exerting?

Like you need to be a sleep scientist? This is absolutely.

That's why I've got you on here.

You don't need me, actually. So the answer is in part yes. But what we've. So for most people though, lucid dreaming really means not only I'm aware that I'm dreaming, but now I can control what I'M dreaming about.

Do you often have lucid dreaming?

Do we often, as a group, you individually? No, I personally I've only experienced lucid dreaming probably, you know, six or seven times. And it's great when it happens. But right now we know based on the population statistics, about 80% of the population does not lucid dream. 20% of the population does lucid dream. Which then brings us on or back to your astute question, which is, can we control our dreams and is that a good thing to gain lucidity and to gain control and to give over the driving seat to me, the individual, rather than to Mother Nature's blueprint that she's worked out. And I can play both sides of the, the theory equation here. On one side, I would say if lucid dreaming was so beneficial to you as a human being, as an organism, then many more people would be natural lucid dreamers than there are now. That would just, there's. That statistic would be reversed if anything.

Well, I mean, if sleeping an extra couple hours a night is more beneficial, which it is, then more people would also be sleeping more.

Well, that's, that's the hard part is that with lucid dreaming, it's very difficult to control. But to choose not to sleep, that's unfortunately very easy to control.

A lot of, a lot of people think it's difficult.

Well, we'll come back to it. I mean, there's really two separate things with insufficient sleep. There is you either not giving yourself the opportunity to sleep or society not giving you the opportunity to sleep despite you being able to sleep very well.

Right, right.

Versus you giving yourself plenty of opportunity to sleep. But just because you have a sleep disorder or you have sleep issues, you cannot generate the sleep. So the difference is opportunity is present, but you can't create the sleep versus you can create the sleep, but you don't have the opportunity to do so. And those two things are quite different. But from the lucid dreaming perspective, I could come back and argue the other side, which is to say my assumption there, the belief that Mother Nature would have had us all doing it if it was good, makes the wrong conclusion that we've stopped evolving. In other words, what if that 20% of the hominid population who are lucid dreaming is the next wave of evolution? They are the superhumans who will come next and succeed. People like me who aren't natural lucid dreamers. So I can play both sides of it.

Interesting. Is there a way to train your mind and body in order to lucid dream? More.

There have been some attempts. So there's a scientist called Stephen LaBerge who actually has an institute of lucidity, and he's got different courses and classes. How effective they are, it's a little bit unclear. And there are some simple techniques where you can, firstly, before you go to bed at night and it sounds hokey and strange, is just repeat like a mantra to yourself, I am going to try and become conscious in my dream. I'm going to try and become conscious and then you can do virtual reality testing in the dream and you can do this when you're awake. So right now, you know, I am looking at my laptop and, you know, if it's a physical entity and I'm in the real world and I'm awake, if I were to tap my screen, I can feel it physically. And you can go around and keep reminding yourself, you know, I can go over to the light switch and turn it on, turn it off. Do I have voluntary control of what's going on in my environment? Because often you don't have in your dreams. And then by doing that in your waking day, you can try to train yourself to do that during your sleeping, dreaming life. And at that point when you flick light switch and it doesn't change anything, or you tap the screen of your laptop and your hand goes completely through it, then you think, oh, hang on a second, this isn't waking. You know, this is clearly a dream. So there's different ways that you can test the reality of waking life versus dreaming life and adopt that mindset. The other thing is just to simply start trying to remember your dreams some more. So in the morning when you wake up, that's the first step towards a path of lucidity. Don't jump out of bed and sort of just close your eyes and try and remember your dream. Instead. Wake up and then keep your eyes closed. And don't try to write the dream down, don't try to dictate it, just rehearse the dream. Because dreams have this funny nature to them where as soon as we wake up, they almost evaporate so quickly from our brain.

And yeah, yeah, if you don't feel it right, then in moments or minutes, it's going to be gone.

It's going to be gone. So just wait there and try to crystallize it. Try to set the dream in amber by sort of, you know, going over it and rehearsing it, rehearsing it in your mind. Build that picture, build the memory, ingrain the memory and then pick up your pad of paper and your pencil next to you on the bedside and write it down. And gradually, as you start to remember more of your dreams, there is some evidence that that can also increase the probability of lucidity. But in truth, I'm not really, and I don't know anyone who is truly an expert in being able to, you know, increase the frequency with which you can lucid dream. From a scientific perspective. There's lots of people out there who claim, you know, I've got this course that you can do and. But the science doesn't support it that well. But the science now has proven without a shadow of a doubt, by the way, that there is a thing called lucid dreaming. We used to think it was a charlatan science, that it wasn't real. And we can go into the details as how you prove it, but it has been proven lots of different ways.

Yeah, and what is the. Do we have any research on what lucid dreaming does for healing the body or hurting the body or the brain?

We haven't found evidence that it either hurts or helps. Right now all we have is evidence. Understanding what happens when you become lucid as a dreamer. And this comes back to what you were asking about, which is, is there an additional metabolic consequence of going into lucid dreaming? One of the fascinating things when we go into dream sleep. Well, there are many, but I'll give you just two. The first is that when you go into dream sleep, your brain paralyzes your body. You are utterly incarcerated in physical lockdown. And the reason is very simple. Your brain paralyzes your body so the mind can dream safely, so that you don't act out your dreams, so you.

Don'T go move your body and.

Yeah, correct. And so what we know is that the mechanisms that control REM sleep and non REM sleep start deep down within the brain, in fact, in the brain stem. So if you were to take a purr, a fruit like a purr, and you were to turn it upside down, it's that sort of, you know, thin end and the stem of the purr, that's your brain stem. It's there where the principal battle for non REM and REM sleep plays out across the night to create the 90 minute cycle of non REM to REM sleep in humans. But as it's expressed upstairs into your brain during REM sleep, which activates lots of brain areas but also deactivates them, there's a separate signal sent south of your neck right down into your spinal cord, which paralyzes what we call the alpha motor neurons, which is all of your voluntary skeletal muscles. Now that fortunately means that your involuntary muscles, things like your heart and your inspiration, keep going. Don't worry, they keep going. Otherwise we would have been popped out the gene pool together very quickly. But your voluntary muscles, those are paralyzed. The second interesting feature coming back to lucid dreaming though, is that many parts of your brain, when you dream, light up. The visual areas at the back of the brain, the motor strip, areas across the top of the brain, the emotional centers and the memory centers, all of these things light up. And some of them in fact are up to 30% more active when you're in dream sleep than when you're awake, which in some ways is fascinating. But the one part of your brain that goes in the opposite direction is something called your prefrontal cortex. And this is sort of, you know, it's like the, like the CEO of the brain. It's very good at making high level, top down executive control decisions and communication. That part of the brain, as we go into dream sleep, is actively inhibited. So your rational, logical brain is shut down and all of these emotional and memory centers light up. No wonder dreams are bizarre, illogical, hyper associative, filled with memories, filled with visual aspects, often have kinesthetic aspects to them. But what we've realized is that the difference between dreaming and lucid dreaming is that that prefrontal cortex part of the brain actually comes back online as we become lucid. In other words, as we gain volitional control over what we dream, the prefrontal cortex seems to be coming back online, gifting you that volition to do what you wish in your dreams.

I've had, I don't know, maybe a handful of times where I've had this dream where I wake up, my eyes are still asleep, but I'm awake. And then I open my eyes, but I feel paralyzed and I feel like I'm screaming, yet nothing's coming out. And I can't move my arms and I'm like, am I paralyzed? And then eventually like something comes out of my mouth and I can move, but it always feels very weird. It's like paralysis. I don't know if that's.

And what it's called is sleep paralysis. It's a very well known thing. And normally what happens to all of us as were so REM sleep and non REM sleep, as I said, will go in this 90 minute cycle. But what's interesting is that in the first half of the night, that's when you get most of your deep non REM sleep and you don't get very much REM sleep in the second half of the night. That's when the seesaw balance shifts. And now you get much more of your dream sleep in those last few hours especially. And normally, as we're waking up out of sleep and therefore typically REM sleep and therefore typically dreaming, the brain has this beautiful synchrony, this lockstep of increasing consciousness into wakefulness and increasing release of that brain body paralysis. So that as you are regaining waking mental life, your body is released from its physical lockdown, from physical incarceration. However, there are times when, when one leads too far in front of the other and it's called sleep paralysis. And you've experienced it. I've experienced it too. Can often happen when we're under levels of high stress or we're typically sleep deprived. And at that point you become a pseudo aware. You're sort of in this mixed state of consciousness in your. Between the worlds of wake and sleep, as it were, but your body is still in the paralysis. So you are. You can't lift your eyelids. Why voluntary skeletal muscles. You can't shout out. Why voluntary skeletal muscles? And it's often paired with a sense, understandably so, of dread and fear and a presence of someone else being there. And it turns out that this phenomenon called sleep paralysis accurately explains most, if not all of so called alien abductions. Because when you, you know, when was the last time you heard on the news an alien abduction story that happened in the middle of the day? And you know, people were outside at lunchtime with friends at work. You know, they're all eating their sandwiches and then all of a sudden they heard this sound whoosh. And it's like, my goodness, you know, did you see that Tommy was just abducted by alien. You know, it never happens like that. It's usually at night. You're usually by yourself. You describe a presence or a sense in the room. You say that they injected you with some kind of paralyzing agent. You tried to fight back, but you couldn't. It's sleep paralysis.

Paralysis, yeah.

Right now, by the way, it's a, it's not necessarily something to be worried about. If you have it, it seems to be somewhat normal. About 25% of the population will experience it. In other words, it's as common as hiccups. But just be aware that there's nothing wrong with you and it's not that you're being visited by anything strange or there have been some kind of worries in religious sort of domains that you require some kind of, you know, exorcism or there's sort of a long history of that in the past. We understand the biology. It's a basic science fact and it's largely normal. So.

So when someone experiences it, what should they do? Just try to maintain calm and just wait for the body to wake up naturally.

And that's exactly right. You will come out of it and try to, if you can, having heard this, understand what's going on. Sometimes you even. I don't recognize what's going on when it's going on, despite knowing what I know. But gradually I get to the place where I realize what's happening and then I just relax and I say, I'm just going to give it time and I may fall back asleep or I may continue with my, you know, Runway jet propulsion and I hit escape velocity of both consciousness and physical paralysis. And it will be just fine. But it's very disconcerting. It really is a very strange.

Scary, right?

It's very scary. Very scary.

Very scary. What about. What are your. What's the science talk about with promontory dreams? And is there any research on this of people able to kind of predict the future and have these dreams that then come true later in life or things like that? Is there science and research on this?

There's some very interesting data where people have, you know, called, let's say, you know, emergency services or FBI or police to say, look, I had this dream that there was a plane that was going to, you know, undergo some kind of malicious, you know, attack, and it was this particular, you know, airline. And. And then the next day something actually happens on that specific airline and you think, okay, this, surely this is real. Not so. So let's just play the statistics game. So you probably go through three or four or usually about four to five cycles of dream sleep a night. And let's just assume that you only have one dream. For each one of those cycles, you usually have more. But let's just assume that. So you're going to have five dreams per night and then that's, you know, six, five, six, whatever. The recent count is seven billion people across the planet having seven billion times five dreams per night. The statistical law of predictable averages would absolutely confirm that someone somewhere is going to have a dream that mimics something that happens the next day. It's just chance. It's just statistics working the way that they do. And of course, when we hear it, as I first described it, you think that has to Be real. But when you apply scientific rationale to the problem, you realize in fact there should be many more of those things that are reported based on statistical chance alone.

Interesting. So there's no, there's no science that backs that people can have dreams and they can predict events or things that happen.

There's no future forecasting that comes by way of dreams? No.

Really Interesting. Okay, what is the.

Well, not that we have of yet. You know, as a scientist you, you always have to take that mentality. I, I think it's very important that scientists should never forget the following truth. Absence of evidence is not evidence of absence.

So it's potentially possible we just have, don't have evidence scientifically that backs it.

Yeah, right now all I can do is operate in the realm of rational fact. And I, on that basis I can tell you we have no supportive evidence.

Have you studied any like quantum physics or done any research with quantum physics and dreams and how like any of that plays in, you know, just kind of thinking a positive thought and then, and then in the dream creating it and then manifesting your life as any of that kind of weirdness come to you or that you've seen.

So we've, we've done a little bit of this that touches on the topic and what we've tried to do is for example, manipulate people's emotions before sleep. So firstly what we know is that your emotional and mental health are very intimately related to your sleep health and it's bi directional. And so, oh, I forgot to speak about the second benefit of dreaming. But we'll come back to that which is creativity and memory and sort of problem solving and insight solving. But with emotions it works both ways. So if you manipulate people's mood during the day or particularly during the last hour before bed, mood and emotions will have an impact on your sleep. And then conversely, how well you've slept will change how emotionally reactive and pendulum like and emotionally irrational you are the following day. So to come to your point, we have which is sort of manifesting positive mindset or mood. If we do a negative mood induction before sleep and we get people to say, focus on something that was, you know, really difficult in your life, think about it, you know, increase that sadness, it has a deleterious impact on sleep. Whereas cultivating a positive mood before bedtime actually improves the quality of their sleep, what we call their sleep efficiency. And so that's about as far as we've got in terms of, you know, augmenting or changing your waking state before sleep to see if it can have either a beneficial enhancement or a blast radius consequence on your subsequent sleep at night. And then we've done the opposite. We've manipulated your sleep at night and then looked at how you become emotionally unhinged the next day. Right, as it were. And, you know, that should be no surprise for, you know, a parent. I don't have children, but, you know, it's often that idea of a parent holding a child. The child is crying and they look at you and they say they just didn't sleep well last night. As if there's some universal parental knowledge that bad sleep the night before equals moodiness, mood and emotional reactivity the next day. The same is true for healthy adults.

Yeah, exactly. Have you ever heard about people that can have a dream and then connect with someone else in their dream and actually have like a conversation or share dream experiences? Is that a possibility? I'm throwing out some weirdness here. I'm just curious if this is any, any studies of this or any research done where it's like, okay, me and you, we're going to try to find each other in a dream and experience the dream together. Is that even possible?

We've got no good evidence for that. Again. But the thing is, I don't know of anyone who's actually tried to study that. We're only now just trying to study cooperative brain activity in waking people. Normally, the way that we do experiments in brain science is that we will put people inside of a brain scanner and we'll do lots of different things with them and we'll try to understand how their brain is accomplishing those things. Only recently because of expense in part and practicality, if you get two brain scanners in one room, you know, next to the other, and then you put two people in those brain scanners and you have them cooperate and perform at the same time. Let's say they're doing some kind of cooperative gameplay or they're going through the same emotional experience. Can you see similar coordinated brain activity that's going on? Does that mean that they are psychically or physically, you know, bonded through some connection that we can't see? Probably not. It just means that when two brains are doing the same thing at the same time, they express the same pattern of signature activity. But we've. It's much more difficult to try to do that experiment with dreaming because most people can't coordinate, you know, it's hard for us to control what one person is dreaming about, let alone coordinate the co experience of two people at the same time. And be measuring their brain activity. So it's just a very difficult question, and I suspect probably not. I suspect most organisms, including humans, will retreat to a solo location. And sleep is typically as a dream conscious experience, a unique individual experience. It's where we, if anything, stop processing external worlds and external events and people. And we start to focus internally on the information that we've gathered during that day and start to ask, based on everything that I've learned today, how does it fit into all of my back catalog of autobiographical experience? And this is where we come to the second benefit of dream sleep, which is that dreaming is a form of almost. It's informational alchemy. Dreaming is a little bit like group therapy for memories that sleep gathers in all of this information. And in this wonderful, bizarre theater that we call dreaming at night, it starts to collide different pieces of information together and starts to test whether they should be connected. But it's not an obvious logical connection. It's not. When you're awake, you do a Google search, gone right, which is your brain calculates the associations and it puts you on page one. When we're dreaming, it does the opposite. It takes you straight to page 20, which is some hyper associative crazy link. But I think that that's important because it's two different modes of processing. Logical, convergent, rational versus illogical, divergent, irrational. And when you do that type of hyper associative processing, you start to see patterns that you can't see while you're awake. And what we've discovered is that the second benefit of dreaming is creativity, that you go to sleep with the pieces of the jigsaw, but you wake up with the puzzle complete. And it's the reason that no one has ever told you to stay awake on a problem.

Yeah, they say sleep on it.

Correct.

Sleep on it before you make a decision. Sleep on it.

That's right, yeah. Both from the emotional standpoint, that it creates resolution, so you're a more rational, balanced, emotional individual making the right choices. And also from an ingenuity perspective as well, from a creativity perspective, you know, we, we end up seeing solutions to previously impenetrable problems. Lots of anecdotal evidence for that in the sciences, in the arts, and in music. And then now in the laboratory, we've been able to replicate that same effect.

I want to ask you about the impact of love and sleep. When someone feels an overwhelming feeling of love, connection, intimacy with a partner, does that support their sleep and improve the quality of their sleep? Does it hurt the Quality of their sleep and is there a difference if they're actually hugging and feeling love and connection to their partner, feeling that, you know, that heartbeat or that, that warmth or whatever it might be that they're feeling, Is there a difference if they're just feeling it but they're not next to them in the same bed? What's your thoughts on this topic?

I think the best answer is it's complicated. But let me pick it apart. Firstly, what we know is that couples who have a strong loving relationship typically have overall significantly better sleep, both quantity as well as quality. When that relationship deteriorates and there is conflict, typically sleep is worse. We also know that there's just a very strong relationship between sleep and sex for the following reasons. Firstly, we know that your sex hormones are powerfully affected by sleep. So if I take a healthy young man and I put them on four hours of sleep for one week, they will have a level of testosterone which is that of someone 10 years their senior. So a lack of sleep will age a man by a decade. In terms of that critical aspect of wellness and virility, you see exactly the same profile in women. We see that insufficient sleep is linked to a reduction in estrogen, in luteinizing hormone and also in follicle stimulating hormone. All of which are critical for female sexual health and reproductive health as well. What we've also found is that when, for example, a woman gets an extra hour of sleep, her desire to be physically intimate with her partner increases by 14%.

Guys need to listen to this.

So you know, and certainly when it comes to testosterone as well. Right, right. And what we've then found at the psychological relationship level is also interesting. When couples aren't sleeping well, firstly they have more conflict. Secondly, not only do they have more conflict, they don't resolve that conflict as well. And part of the reason that they don't is because they lose empathy. Right. They just moody empathize. Right. They become more self centered and less compassionate towards the other.

Yeah.

So for all of those reasons, you can see this, this bidirectional relationship regarding sleeping together in the sense of physical sleeping in the same bed. The data is very interesting. What we know is that about 30% depends on what survey you look at, but about 30% of people surveyed anonymously, and it usually has to be done this way, will report not sleeping in the same bed. Of those who do sleep in the same bed, a significant proportion of them, up to 40% of them will report waking up in a different location for whatever reason. And, and this is what we've then. Because the stigma at first is that if you're, if you're not sleeping together, then you're not sleeping together. But the opposite seems to be true for those specific couples for whom it works when they start to sleep apart. Firstly because their sex hormones improve and the desire for each other increases. Typically the physical intimate relationship is improved by way of what we call that sleep divorce. So a sleep divorce can actually help you prevent a real one in that sense. But it's not a one size fits all. It's. I'm not suggesting that by any means for some people sleeping together works very well that overall what we know is that when people sleep together objectively the quantity and the quality of their sleep is worse. On average it's worse.

However, sleep in the same bed objectively the quality and the quantity and the.

Quantity of their sleep is worse. However, if you ask them what they felt their sleep was like in terms of their satisfaction with sleep, on average, they will say that they felt more satisfied by their sleep when they were sleeping together. Now that could just be because of this sort of stigma and this bias towards how we think we should sleep as couples. But I want to give people the permission to undergo at least this exploration with your partner because there are many reasons sleep disorders such as sleep apnea, sleep snoring, tossing and turning. We know that when one partner starts to toss and turn, it has a knock on effect like a domino causes the other to have a bad night of sleep. So there are several ways that you can think about this. Firstly, have a conversation and you don't have to admit it to the outside world if you don't want. I've admitted to this before having a sleep divorce. I would say that it's fine to tell people I love you, I care for you, I don't sleep well when we're together often and I think I would be a better partner if I could try to sleep in a separate location. However, the funny thing is most of us for the majority of that nighttime period we're non conscious. So we're actually not aware of the other partner. What we miss I think is the bookends of sleep going to get into bed saying good night, having a cuddle and waking and then it's waking up and saying so you can, you can kind of hack the system. So whoever goes to bed first, depending on chronotype, morning type, evening type, somewhere in between, and we can speak about that too, whoever goes to bed first, that it's the job of the Other person to come through. And as they, they can send them a text and say, look, I'm about to turn the light off, can you come through? And you go through and you give them kissing, a cuddle and you have your little sort of bedtime moments of front end, lovely. And then on the back end, whoever wakes up first, they, you know, get to the kitchen and they start making their tea or coffee, whatever it is. And then the other person, as they're waking up, they text them and say, I'm just waking up, come through and you can go through to the bedroom and you can have your back end bedtime sort of unit union when they wake up. It sounds like a lot of work, but the, the cost benefit that you get in terms of healthy sleep and how good you will feel and how much better the statistics tell us relationships are when couples are, well, slept, I think is worthwhile at least exploring that. So it's a. Not once, it's not a one size fits all. I'm not suggesting that different people find different. Some people find it very safe to sleep with another partner because there is a degree of threat for whatever, you know, historical psychological reasons, or they just feel better about having someone else there from a threat perspective, which I totally understand too. So just explore it with your partner.

What does the data say about animals? Pets in the bed with you? You're going to, you're going to get a. Ruin every animal. Dog lover, cat lover.

You know, I often say I'm not a particularly popular person just by my personality and maybe nationality, but this makes me even more unpopular, which is sadly, pets are not a good outcome. They're not a good impact on your sleep. Human beings will typically sleep worse when pets are in the bed. So the advice is, you know, again, but what if there's so much love.

You have this love in your heart, you feel this connection and it allows you to peacefully, restfully go to sleep.

Sleep as a pet person as well. Dogs and cats and, and other species.

Is that, Is that animals in bed? Is that animals in the room next to your bed?

Is it animals in the room? As long as they are trained not to wake you up for whatever reason, I'll bark.

They don't poke you. They don't.

Yeah, right, exactly. Not so bad. But if they're in the bed, not so good. But I, all I can tell you is the data. And you know, if we speak about alcohol, caffeine, drugs, it is not my responsibility as a sleep scientist to tell anyone how to live their life. Right And I'm not going to tell anyone that they should or should not, you know, sleep in the same bed with their partner or have their animal, their pet in the bed. You know, you should live life on your own terms. And all I'm here to do is try to empower you with the science and the knowledge of sleep so then you can make an informed choice as to how you want to live your life. I have no business telling anyone how to live their life, let alone try to fix my own.

What does the science say about the people that live the longest? The people that live in the blue zones? How are they sleeping? What is the quality of sleep they get? Is there research around that?

It is interesting that when you look at some of the blue zone areas in some of those communities, what we typically see is that they will have two bouts of sleep. They will have a long bout of sleep at night, and then they have a siesta, like nap in the afternoon. And there is some evidence physiologically that maybe we were designed as a species to be napping during the day. And we can speak about that in detail, too. But to your question, there's a great island. I don't know if it falls into one of the blue zones, but it certainly should. It's a Greek island called Ikaria. And there the people have a wonderfully healthy lifestyle, but they also take naps during the day. And I think males there are almost. I could be getting this statistic wrong, but they're almost twice as likely to reach the age of 80 as any male American in America. And in fact, the island has often been described as the place where people forget to die. Isn't that lovely?

Wow. Well, now. Now also, I mean, there's probably other factors. They're probably outside in the sun more. They're eating a certain lifestyle of food.

Food. They're probably more physically.

Social connections.

Social connections. And so all of those factors is sleep. A missing piece is the explanatory puzzle of the blue zone equation. It's actually never been studied. I should speak to Dan Buettner and sort of see if we can get some statistics on that. My guess is that it's. If you add up all of the factors that they have right now. Let's.

Which is nutrition. Social connection.

Yep.

Physical activity.

Moving. Physical activity.

Where that. I think. Yeah. Isn't it part of like the amount of sun. Sunlight. Or how close it is.

Light exposure and. Yep. Sort of those. Those things and having purpose in life and. Yeah. That sort of community. If you were to add up all of those factors and then say of when you combine them all, how much of the variance in lifespan do you explain? Maybe you can explain 80%. So you can predict with 80% accuracy, you know, the lifespan of an individual when you know all of these five things, the blue zone things, let's call them, that means that there's 20% left on the table. Now, is sleep going to accommodate and absorb some of that additional variance that we can't yet explain? My guess is probably yes.

Yeah. And I'm guessing they're not sleeping three hours a night. You know, they're probably sleeping. No, seven, eight, usually sleeping, Right?

Right, yep. Six to seven hours of sleep at night and then they will have that siesta like activity in the afternoon, making up exactly what we typically predict, which is somewhere between seven to nine hours of sleep.

Now, is five hours of sleep plus a two or three hour nap acceptable? Is it six hours of sleep plus a one hour nap acceptable? Does it still transfer over or do you really need that seven hours minimum of kind of deeper sleep at night? And then if you get an extra 30 to 60 to 90 minutes in the afternoon, that's a bonus. How does that work?

It's certainly probably not as large as the first example you gave. Sort of, you know, five hours at night, then a three hour nap during the day. That doesn't seem to be biologically, physiologically how we were designed to sleep. But if you look at some of the cultures that have been untouched by sort of modernity, they, especially during the warm summer months, they can have a period where they'll have, you know, six and a half to seven hours of sleep at night and then a short siesta like nap in the afternoon. So certainly it seems to be for the full 24 hour period, a minimum of 7 hours is required, usually in one large amount of sleep at night and then perhaps one short sort of soups on little sampling of sleep in the afternoon in that nap like behavior. I would say with naps though, they can be a double edged sword and you have to be a little careful. We and others have shown time and again that naps can have very powerful benefits for the brain and for the body. They can improve your mood, your emotions, enhance your learning and memory. They can lower blood pressure, they can boost the immune system.

Right.

But naps are potentially dangerous because during the day, from the moment that you and I both woke up this morning, a chemical has been building up in our brain and that chemical is called adenosine. And the more of that chemical that builds up the sleepier you will feel. And after about 16 hours of being awake, you should feel heavy enough with that sleep pressure to fall asleep and stay asleep. And then when we sleep, what's beautiful is that sleep gives the brain the chance to evacuate all of that sleepiness, all of that adenosine out of the brain. So after about eight hours, you have jettisoned 16 hours of sleepiness chemical of adenosine, and you wake up naturally. Why is this related to naps? It's related to naps because if you take a nap that's too long or a nap that's too late into the day, it's a little bit like a valve on a steam cooker that you remove some of that healthy sleepiness, that sleep pressure, so that when it comes time to fall asleep at night or try to stay asleep, it's not as easy anymore because you've removed some of that burden. So I think, you know, napping late in the day or napping for too long, it's a little bit like snacking before your main meal. It just takes the edge off your sleep, appetite and hunger, if that makes any sense.

What's the latest we should be napping, and what's the longest we should be napping?

I would usually say cut naps off after about 2pm and assuming a standard prototypical bedtime, of which, you know, it varies. And then I would say try to limit your naps to probably no more than 20 to 25 minutes at max. And the reason is because if you go longer than that, you can start to go into the deeper phases of sleep. And if you wake up after an hour, your brain is in the deep stages. And then when you come out of that nap, you can typically feel worse. You almost have what we call a sleep hangover, right? This technical term is sleep sleep inertia, where it takes you then about another hour and a half to kind of wake back up because you went too deep, as it were. So the best advice is the following. If you are struggling with sleep at night, do not nap during the day. Build up all of that healthy sleepiness. Give yourself the best chance to get to sleep and stay asleep. But if you can nap regularly and you're not struggling with sleep, naps can be just fine. Maybe cut them off, you know, depending on your bedtime, 2 to 3pm and try to keep them to around 20 minutes.

I'm curious about diet and nutrition and food choices and how it impacts sleep. And also alcohol. I would put caffeine, smoking, Cigarettes as another category and maybe there's three categories. But if someone is drinking a cup of coffee a day or multiple cups, or they're having a few cigarettes or drinking alcohol, any of those categories, how does that affect the quality and the depth of the sleep that you have?

So this is where I become even more unpopular. There is. So let's start with caffeine first of which I've changed my tune actually over the years. I will tell you, drink coffee, which sounds strange coming from, you know, a sleep scientist.

Just only drink it before a certain time, I'm assuming. Right.

So the dose and the timing make the poison. If there is a tagline for coffee, that would be it with regards to sleep. And it's the reason is, is this firstly, coffee has been associated with some wonderful health benefits. And in fact, people have often reached out to me and I'll soon release one of my podcast episodes on this explaining this in more detail. But they would say, look, coffee is associated with lots of health benefits, in fact, many of the same health benefits that sleep is associated with. And we know that caffeine is not great for sleep. How do you reconcile that paradox? It seems to be counterintuitive and there's a very simple one word answer. Antioxidants.

Right.

Because the it turns out that the humble coffee bean has now had to carry the weight of infusing most people who eat a poor diet with their major source of antioxidants each day. And in fact, if you look at the American population, and the same is true in many European countries, because we don't eat in a holistic way in whole foods and get all of our nutrients and antioxidants. The coffee bean is the principal source of most of our antioxidants. So it's not the caffeine that causes the association between coffee being good for you, it's the antioxidants. And a good demonstration of this is decaffeinated coffee, which still contains the antioxidants and is still associated with many of the same health benefits.

Interesting.

So certainly most of us, you know, many people will like to wake up, they will enjoy, you know, coffee or two in the morning. And that's great, definitely do that, no problem. Be mindful of whether you're sensitive or not. And it depends on your genes. And a certain type of liver gene that dictates an enzyme, they're called cytochrome P450 enzymes that degrade certain compounds. And there is a gene that if you have one variant of it, the gene is called CYP1A2, if I'm getting my nerd genes correct. If you have one version of that, you metabolize caffeine very quickly. If you have a different version of it, you metabolize caffeine very slowly. Unfortunately, I am one of those individuals who is a slow caffeine metabolizer and I, you know, I can have one cup of, I drink decaf, but if I have one cup of coffee in the morning, for the most part, it won't impact my sleep at night. But let me come back to the dose and the poison part. One of the problems with caffeine is that it has a half life in the average adult of five to six hours, which means that it has a quarter life of about 10 to 12 hours. So in other words, if you have a cup of coffee at midday, then a quarter of that caffeine is still circulating in your brain at midnight.

No way.

So it would be the equivalent of a cup of coffee at midday, would be the equivalent of getting into bed. I sometimes sort of note, and before you turn the light out, you swig a quarter of a cup of Starbucks and you hope for a good night of sleep. And, and it's probably not going to happen. So the first issue is the duration of its action. The second concern with caffeine, though, is some people will say, look, I can have an espresso with dinner and I fall asleep fine and I stay asleep. So it's no, no problem. Even if that's true, what we've discovered is that caffeine can decrease the amount of deep sleep that you get. And so that you wake up the next morning and you don't remember having a hard time falling asleep, and you don't remember waking up and finding it hard to fall back asleep, but you don't feel refreshed by your sleep. And so you're now reaching for two cups of coffee rather than one in the morning. And just to give you a context, drop your deep sleep by 20%, which is what caffeine can do at night. I would have to age you by about 15 years or you can do it every night with a cup of coffee.

So if you have coffee, drink it before, what, 10:00am Well, I would say.

You know, see how your sensitivity is. Certainly I would wish for most people assuming a typical bedtime again, of cutting it off before midday, try to limit yourself to maximum 3 cups, 2 cups if you can. What we do find, by the way, those health associations with cups of coffee once you get past sort of Three or four cups, it starts to go in the opposite direction. Actually has, you know, it doesn't have those health benefits.

And if you're going to do a cappuccino at night, just do decaf.

Just do decaf. It's actually doesn't taste too bad in the end. And it will save your sleep. Yeah.

Oh, yeah.

And then I can come on to alcohol if you want. And yes, really, please put the nail in my.

Well, I've never actually. I. Most people know in my. My. My life and also on my show that I've never been drunk. I've never. I've had sips of alcohol in my life. I didn't have a sip in four years of college because I just made a commitment to be a better athlete and have better performance. When all my teammates were drinking on the weekends and I could see that they were sluggish the next day in practice, I was like, this is my way. And I just kind of was like, why start after college? I maybe have like a Bailey's on Ice once or twice a year. Just like, sip on.

And that's you rebel, Louis. Listen to you.

I know, I know, right? And it's just like a little sweet milk or something. I. I've always felt like, man, people just don't seem to make good decisions or they don't wake up better after they have alcohol. So it just, you know, I knew I needed advantages in my life somewhere when my vice is sugar, so. Which is probably gonna be the next thing you talk about, but how does alcohol affect sleep? And does it matter the. The portion and the potion of when.

So I should admit right up front, too, I'm like you, I'm not a big drinker, which means I probably should have had my British passport taken away from me long ago. I think it's a birthright of many. But what we know is that alcohol will hurt your sleep in at least four different ways. Or it has four consequences, I should say. The first is that when people say, look, I have a couple of drinks in the evening and it helps me fall asleep. The problem is that alcohol is in a class of drugs that we call the sedatives. And sedation is not sleep, but when you've had a couple of drinks in the evening, you mistake the former for the latter. And sedation is where the brain, simply, the brain cells are switched off and they essentially, you're knocking out your cortex. But when you go into deep sleep, it's very different. Deep sleep is a time when hundreds of thousands of brain cells, all of a sudden they coordinate in their firing and it's unlike any other time. We see during the 24 hour period, all of these brain cells fire together and then they all fall silent and then they all fire together and then they all fall silent. It is this spectacular physiological ballet. And that type of sleep is very different to sedation. So that's the first issue. The second issue is that alcohol will fragment your sleep so that you will wake up many more times throughout the night. It will litter your sleep with many awakenings. And lots of people sort of, you know, I wear the oura ring and I'm, I'm related to the company too. But a lot of people will say with their aura data, you know, after I've had a night of some drinking, I just see my sleep is decimated. I'm very punctuated with all of these awakenings. And that's what we call sleep fragmentation. That's poor quality of sleep. And sleep quality is just as important as sleep quantity. The third problem with alcohol is that it's very good at suppressing your REM sleep or your dream sleep, which is what we've, we've spoken about, has many benefits, by the way, including other benefits down in the body. We know that it's during dream sleep when the body releases in both men and women, highest amounts of testosterone. So if you're blocking your dream sleep and you're drinking, particularly in athletic context, you need that testosterone for recovery and restitution of muscle mass and muscle growth. So, and then the final thing coming back to muscle growth is that if you lace people with alcohol at night and the sleep disruption as a consequence at certain phases of sleep, it can cause a 50% impairment in the amount of growth hormone that's released 5, 0 at night. So again, I want to back up though here, and I really think this is important. I don't want to be puritanical and I don't want to wag my finger. You know, life is to be lived to a certain degree, of course. Live your life and don't let anyone tell you how you want to sort of live your life. As long as you're not hurting anyone doing anything wrong. Live your life as you, as you wish.

But I understand the consequences that the data speaks to that People who do certain things tend to not live as long or tend to have worse quality sleep or age faster based on the data. Maybe some people can get away with certain things or live a little longer and have a glass of wine every night, but they have everything else in their life going for them in, you know, or something, you know, and maybe.

The choices that you say, you know, I would prefer to live a shorter life with less sleep. Right. And, you know, that's. That's.

You live it on my terms.

Right. I wouldn't wish you to do. Right, exactly. Is do it that way, unwittingly or unknowingly? Once you're imbued with that knowledge and you still want to make that choice, then I. If that's the flag that you're hoisting, I'll. I'll salute it every single day. But I just want you to at least have the evidence so that you can then do whatever you want with it. That's all my job is. I'm not here to tell you what is the.

You know, based on the data, what would you say would be a suitable amount of alcohol? Someone could drink on a weekly basis where it wouldn't affect too badly their sleep, but it wouldn't be the best thing. But it'd be like, okay, this is doable. Is that a couple glasses a week? Is that a glass a night? Is that one glass a week, like five shots at a time? You know, what is this?

We've even seen that one glass of wine at night will have an impact.

One glass of wine every night will have an impact. What if it's one glass?

We haven't actually done the studies where we repeat across multiple nights. Just one glass, just one glass will change the composition of your sleep that night.

And if you do it every night, one glass that's probably going to have.

Compounds, may have deleterious consequences, is the suspicion, you know, and I think the politically incorrect advice that I never give on podcasts would be the following, that you should go to the pub in the morning, and that way the alcohol is out your system before the evening. But I would never suggest that, you know, it's just you and me here, no one else.

Exactly. So if someone. If someone did want to have a glass of wine over lunch, let's say between 12 and 3pm and they went to bed at, you know, 10 or midnight, how would that affect their sleep?

It's possible, depending on how successful your liver and your kidneys are and what the strength of that alcohol is, that it may be. It may have been metabolized and cleared from the system sufficiently that it wouldn't have an impact on. On sleep. But I don't know anyone who's tried to really do the dose response curves of that question, which is you know, let's start with this proof of alcohol, you know, 10% or spirits, whatever it is, 40% beer, what, seven, whatever it is. And then let's do that and see the impact. And then let's bring, let's march that dose from the afternoon closer and closer and closer to sleep and see if the detriment to sleep is a linear relationship, that the closer you get, the worse the consequence of your sleep. Or is it more of a, an exponential, a sort of a ramping up curve where it doesn't have too much effect in the afternoon, but then it's really in the last two hours, especially in the last hour, the last three hours when it climbs. That's when you have a monumental impact on sleep. And then it, you know, I don't know if that makes sense, but I don't know. That would be the study that I would want to do. It's just immensely costly and probably no one wants to fund that study.

And what about the impact of cigarettes, cigars or mushrooms or other type of drugs that are now becoming more popularized? The mushroom kind of community? The, yeah, the, not ayahuasca, but whatever's in between mushrooms and ayahuasca, kind of like those types of drugs. How do those impact or even marijuana, how does that impact sleep quality?

So we, there is emerging evidence on CBD and thc. I think the best evidence we have so far is on thc, which is tetrahydrocannabinol, which is the psychoactive component of marijuana. That's the stuff, that's the part that gets you high. We know that that unfortunately is not good for sleep for at least two reasons. Firstly, people will say it does help me fall asleep quicker and it does seem to hasten the onset of sleep. The problem is that you develop a tolerance, you develop a dependency very quickly, and then when you stop using, you have very horrific rebound insomnia and therefore you have to go right back to it. So you develop a dependency on the drug. So that's the first reason that we don't advise it. The second is that it seems to. THC seems to be very good, like alcohol, but through a different mechanistic pathway. It seems to be very good at blocking your dream sleep, your REM sleep. So unfortunately, THC is probably not advised from a scientific perspective. Cbd, however, is interesting. I, you know, I'm not a medical doctor and I'm, I, you know, none of the, what I say here or anywhere else is, you know, prescriptive advice or medical advice, but the Scientific data on CBD is starting to become quite interesting. Many people have suggested that they use it and it helps their sleep. If you look in some of the animal studies, at higher doses, CBD does seem to improve some aspects of deep sleep, deep quality sleep. The dose also is interesting though, and this has not been spoken about widely in the community and I think it's disservice. At low doses, CBD may actually be wake promoting, it may keep you awake, whereas at higher doses it may be more soporific, it may be more what we call somnogenic and increase sleep. The question then to me is that if that data is real, I'll start to believe it more if I can come up with a plausible physiological mechanism that underlies it. And after doing a lot of research on this in this area and reading, I think there are at least two non mutually exclusive possibilities as to why CBD may be. And I don't think there's anywhere near enough data suggest that it. It does, but it may have an effect. The first is that it seems to be a very powerful, what we call anxiolytic. In other words, it decreases your anxiety. And there's some great science around CBD and anxiety right now, even within the brain. You know, we spoke before about how you become very emotionally irrational without sufficient sleep. And in part it's because a deep emotional center called the amygdala erupts and becomes at least 60% more reactive when you're not getting sufficient sleep. That same emotional epicenter, the amygdala, is actually quietened down by cbd. Some great studies there. And we know, and we spoke about earlier on, that anxiety is one of the, the routes to which you get to insomnia. So I think it has an indirect potential benefit, which is that it quiets the nervous system down, it reduces anxiety. And when you remove the roadblock of anxiety, you enter into the richer world of sleep. The second is a more direct mechanism. And this comes on to something called temperature, because your brain and your body need to drop their core temperature by about 1 degree Celsius, or around 2 to 3 degrees degrees Fahrenheit, for you to fall asleep and stay asleep soundly across the night. And that's the reason that you will always find it easier to fall asleep in a room that's too cold than too hot.

What's the, what's the ideal temperature of the room?

It's different for different people. You know, men typically run hotter than women. But on average, what we found is that a bedroom Temperature of somewhere between, sort of somewhere between 62 to 65 degrees Fahrenheit, which is actually quite cold, a little over 18 degrees Celsius. So now if you're worried about that, no problem, you can take a hot water bottle to bed, you can put it at the end of the bed, warm your feet, wear thick socks. But for the ambient temperature, that seems to be ideal for the average adult 62 to 65. Yeah. So one of the interesting things coming back to cbd, however, is that it seems to have what we call a hypothetical thermic profile to it. In other words, it drops your core body temperature. And by the way, this is the reason that people will think, look, if I have a hot bath or a shower before bed at night, I fall asleep faster and I seem to get a better night of sleep. And part of the reason you think that is because you get out of the bath, you're all warm and toasty, you get under the covers and you fall asleep. It's the exact opposite reason. In fact, what happens is that when you're in the bath or the shower, all of the blood comes to the surface of your skin. Rosy cheeks, kind of red hands, red face. And that means that you've charmed all of the blood out of the core of your body to the surface. And when you get out of the bath, that skin surface radiates the heat out of the core of your body. So after a warm bath, your core body temperature plummets. That's the reason why you sleep better. And in fact, it's so reliable that we call it the warm bath effect. In sleep science.

Is it better to take a warm bath or a cold shower before bed?

Cold showers typically not, because what that will do is usually the opposite. Firstly, cold showers will activate you and sort of, you know, create usually a brain response, including a neurochemical called norepinephrine, which is an alerting, activating chemical. The second is that when you have a cold shower, typically your skin will get whiter as a consequence. And what will happen is that the. The brain is doing what we call vasoconstrance, sorry, the body is doing vasoconstriction. It's, you know, locking down all of the blood vessels because it's trying to hold on to its heat. So you withdraw the heat into the core of the body and you trap the heat. So the usually go for a warm bath or a shower. You know, when you are trying to get to bed at night, that's usually the best prescription.

And what about Nicotine, the effects of nicotine, whether it be vaping or cigarettes, how does that affect sleep?

So nicotine is a very activating chemical. It's a stimulant, it's what we call a psychoactive stimulant. And coffee is a psychoactive stimulant too. But they work through very different mechanisms. So nicotine will bind onto specific receptors in the brain that can activate the brain called nicotine receptors. And what we typically find is that smoking, and smoking before bedtime will usually create sleep disruption and activate the brain. So it will make it harder to fall asleep. But the hard part is when you're going through abstinence. We also know the same with many drugs, when you're trying to quit, sleep usually is disrupted as a consequence as you go through withdrawal. And in fact what we found is that in for example, we've done some studies with cocaine addicts, we found that the severity of their sleep disruption during withdrawal predicts their relapse.

Because I need to just feel like I can sleep, relax and sleep again. Yeah.

Or it's just that when they're not sleeping well, they are predisposed to a making bad choices, they become more impulsive. And we've seen this in healthy individuals. You sleep on depends, deprive them the dopamine circuits in the brain that are reward seeking, impulsive, risk taking. Those circuits of the brain become hyperactive and hypersensitive. So when you're going through abstinence and your sleep is disrupted, what's unfortunate is that you become more reward sensitive and more impulsive. You lack self control. So no wonder it predicts relapse. But the good thing that tells us is if that's the case, can we use sleep treatment, sleep therapy, as a way to intervene during abstinence to see if we can shore up and bootstrap the system so it doesn't fall prey to relapse because of the abstinence induced sleep disruption. Does that make any sense?

Yeah, of course. Yeah, it does. So is there if someone was vaping or smoking cigarettes, would there be a cutoff time, they should stop during the day if they wanted to get better sleep? Or is it just if you're having nicotine at all, at any time during the day, it's going to affect you at night.

The nicotine typically has a shorter half life in terms of its activity. So unlike caffeine, which has quite a long sort of half life, and alcohol too, nicotine has a shorter half life. So the sort of proximity to sleep that you may have to cut yourself off, may be shorter as a consequence. But just keep an eye out, you know, it usually is going to be an activating thing and we see it all of the time. It can be a potent sleep disruptor.

And what about sugar and the standard American diet, the SAD diet, how does this impact our sleep?

Unfortunately, it's not great. So what we found, and there's a, there's a, you know, I seem to be like just the bear gloom. Yeah, I know, I feel like Eeyore in Winnie the Pooh. Everything's terrible. But there is a very strong link between your sleep and what you're eating. And there is an equally strong link between what you're eating and how you sleep. And we can maybe take both of those. There's less evidence actually. Regarding your first question, which is how does what you eat impact your sleep? What we do know for certain is that diets that are high in sugar and low in fiber will typically result in worse sleep. And part of, especially if you're having sugar intake in the last couple of hours of sleep. And part of the reason I believe this is true, although we don't yet have the evidence, is, is that sugar is a very good way to release energy and increase your core body temperature. And what we've just spoken about is that when you go to sleep you need to drop your core body temperature. And that can be one of the many, I think consequences.

So try to have sugar, try to wait, do it two or three hours before at the latest when you sleep.

Would be advise it. Yeah.

And don't have it at midnight and then wait three hours to sleep.

No, that would be ill advised as well from my scientific knowledge.

And what about food in general? Is there a time where you should stop eating before you sleep?

Great question. And in fact that's kind of a bit of a myth when you look at the data that you could bust. You know, people will say you should really cut yourself off, you know, three or four hours before bed. And that's the optimal, if you look at the studies, you can go as close as to one hour before bed eating. And it doesn't seem to have an impact. Once you get closer than one hour, it does seem to have a negative consequence. Also just be mindful of, of acid reflux. That's the other thing. If you have a large meal and then you lie down, a lot of people will get that reflux. That will wake them up throughout the night. And that's another reason a cost of eating too big too late.

Interesting Yeah, I had a couple nights ago I had, I hadn't had pizza in a long time and I'm a big pizza guy and I had a, a pizza. It came like two hours late. It was supposed to come at like eight and then I had the delivery, got messed up. Anyways, it came like 11:30. I was like, ah, do I eat this now or do I just, you know, eat it tomorrow or something? And I kept, I was like, maybe I have one piece. And then I ate like almost the whole thing. And the next morning I woke up and I felt like this acidy type of feeling and I was like, huh, it didn't wake me up in the middle of the night, but I felt it.

At least you don't remember. That's the, one of the downsides too is that you don't remember waking up. But if we looked at your, you know, if we had a sleep tracking ring on you, it's probably likely that, you know, we would have seen some of that restless sleep.

Yes, true. And, but I also felt it the next morning for a couple hours, which was just uncomfortable, you know, feeling that kind of acidy feeling. So that's interesting. Yeah.

So timing, you can, we can sort of bust that myth a little bit. Also time restricted eating, which has been a big thing of late, the studies there are great and you know.

Intermittent fasting you mean or.

Yeah, so I would say it's time restricted eating rather than intermittent fasting because to really call it fasting you have to, you know, not eat probably 36 hours past to say that you're in a fast. But I think time restricted eating, there's some great work. My good colleague Satchin Pandaret down in San Diego at the Salk has done some amazing work in animal models. David Sinclair has got some great data.

Jason Fong.

Yeah, yeah, exactly. These people are great. But what's interesting is that I don't doubt the health benefits. Those health benefits are very clear on multiple metrics of body health and some brain health. But when you look at the sleep data, from what I can tell there are really only three studies so far that carefully controlled studies. Two out of the three were in obese populations. One out of the three was in healthy weight individuals. And what they found was that time restricted eating offered no benefits to sleep. Now it's not that time restricted eating gave any or caused any detriment to sleep. It just didn't offer any benefit. That doesn't mean that I'm advising against time restricted eating. In fact, I do time restricted Eating, but in terms of sleep, unfortunately it doesn't seem to.

It's funny, you hear people who intermittent fast or time restrictive do time restrictive eating say, you know, I sleep like amazing, you know, when I, you know, I sleep so great when I do it. So maybe it's just a placebo effect or something.

Or it's, I mean, I think there's individual variability of course too. And for some people, I have no doubt that it probably creates objectively good sleep. But you should also make the point as you did, the placebo effect is the most reliable effect in all of pharmacology.

Right, exactly. Or also it's maybe you're not, you're also not eating later at night because you're not eating in general. And maybe your body just isn't like metabolizing something when you're right about to go to bed and you're, I don't know, maybe it's not working as hard the body and so you're able to get cooler temperature. I don't know. But that's interesting.

Time restricted eating. Yeah, it's. But we can turn the tables then. That's sort of the impact of food on your sleep. The impact of sleep on how you eat is incredibly well resolved.

So if you get a lack of sleep, does that mean you tend to go after the things that want to give you more energy, the sugary carby type things, and then it's never enough and you keep eating more of it, that type of stuff?

I say you should be a sleep scientist. So you've nailed it. So firstly, what we find is that your appetite regulating hormones go in opposite and bad directions when you're not sleeping well. So firstly, so there are two key appetite regulating hormones, leptin and ghrelin, that I know, I think you've had discussed on the show before. Leptin is the satiety hormone and it signals to your brain that your fat full and that you're satiated and therefore you typically don't want to eat more, you're satisfied with what you've eaten. Ghrelin, on the other hand, is the hunger hormone that will say, no, I'm not satisfied with my food, I want to eat more. And when you are insufficiently slept, the levels of leptin, which is the satiety signal the I'm full, I'm comfortable with my food, that drops away. And if that weren't bad enough, levels of ghrelin actually increase. So you lose the signal of feeling full and you increase the, the signal of hunger and no wonder then as a consequence, insufficiently slept individuals will typically be eating somewhere between 2 to 300 extra calories each day. And you can add that up, you know, day after day, week after week, month after month. And depending on your, you know, how you calculate it, it could be, you know, 40, 000 extra calories every year, which could be somewhere in the region of, you know, four to seven pounds of obese mass that you add on each year because of insufficient sleep. The second thing that we found is that it's not only that you eat more, but what you want to eat changes, just as you described. So your food preferences not only shift to just eating more, but you eat more of the things that are what we call more obesogenic.

Right.

So when you are under slept, you start to reach out for simple sugars and the stodgy, heavy hitting carbohydrates rather than the sort of the protein rich.

Food, vegetables and nuts and.

Exactly. So now you're reaching for this sort of ice cream and the cookies rather than the leafy greens and the handful of nuts. So that's second problem with insufficiency. The third problem that we've discovered is dieting. It's really fascinating. If I take an individual who is not sleeping enough and they're dieting, they're trying to lose weight and manage what they eat. Unfortunately, 70% of the weight that they lose will come from lean muscle mass and not fat. So in other words, when you are.

Without sleeping properly, without sleeping properly.

So when you are short sleeping a set of individuals, this is what we see. In other words, when you're not getting sufficient sleep, but you're dieting, you hold on to what you want to lose, which is the fat, and you lose what you want to keep.

Oh man.

Which is the muscle. Does that make sense?

It makes sense. It makes me sad.

I know, I'm bloody depressing, aren't I? This is why I tell you, I'm just so unpopular, I'm a nightmare.

We need this information. Yeah, exactly. We need this information to help us improve the quality of our life. And that's my mission, to serve people with the right information, with the right data, with the right science that can help them if they could do one thing better to improve, you know, even just a little bit, that'll help them overall. Maybe they're not gonna be able to apply all these strategies, but it's like, what would you say if there were three things someone could do to improve their sleep tonight? Only three things. What would those Three things be for.

You, I think beyond what we've spoken about, which is sort of the alcohol and the caffeine and being mindful of that, I would say firstly, regularity. If there's one thing that you take from this, this podcast regarding sleep, it's regularity. Go to bed at the same time and wake up at the same time. No matter whether it's the weekday or the weekend, really, regularity is king. And I don't like giving rules. People don't respond to rules. People respond to reasons, not rules. And so I'll try and explain the rule, as it were. The, the reason is because your brain has a master 24 hour clock inside of it, sits right in the middle of your brain. It's called the suprachiasmatic nucleus. And it expects regularity and thrives best under conditions of regularity, including regularity of your wake sleep schedule. And if you give it regularity, regularity is king. And it will anchor your sleep and improve the quantity and the quality of your sleep. I think the second piece of advice I would have is have a wind down routine. You know, many of us think of sleep almost like a light switch that we are racing around during the day. We're desperately busy, we jump into bed, we switch the light out and we think that sleep should be like that same light switch. Sleep is much more like landing a plane. It takes time for your brain to descend down onto the terra firma that we call good sleep at night. And we do this with kids, of course, you know, we have to go through the routine, you know. Yeah, we sort of give them a bath and then we sort of get them out and they put them into bed. Then we read to them and then gradually. And if you deviate from that routine, from that wind down routine, bad things are gonna usually transpire. How long, why don't we do that for humans?

Yeah. How long should that routine be? Is that, can that be 10 minutes? Can be an hour. I mean, what's. Does it matter?

I would say find what works for you. I would say usually try to think about some kind of a 30 to 20 minute routine, whether that's taking a bath. I found meditation to be incredibly powerful. I really enjoy the, the app headspace. And I know you've had Andy on the show before too. Fantastic, wonderful individual doing great things. So meditation before bed, you know, stretching, some kind of a wind down routine. The other thing you can do is have a worry journal, just sit down and usually two hours before bed, don't do it right before bed, with a pattern of paper and a pencil, write down everything that's on your mind and it's catharsis and it's just like vomiting out all of your anxiety onto the page.

Right.

And that's to. Yeah, so you don't sleep with it. So you can have that as part of your wind down routine. Find something that works for you. But a wind down routine is critical.

Yeah.

The last piece of advice I would give the third piece is that after a bad night of sleep or if you're struggling with a bout of insomnia, the very best advice that I can give you is do nothing. And what I mean by that is don't wake up any later, don't go to bed any earlier, don't nap during the day and don't drink more coffee. And I'll explain each of them. Yeah. So if you wake up later in the day because you think, well, I had such a bad night of sleep, I need to sleep in a little bit to compensate because you're waking up later when it comes time to your normal bedtime later that evening because you've only been awake for less, you've been awake for less time than you would do normally. You're not as tired. So what happens, you get into bed because you think, I had a bad night of sleep and I want to sort of make this one a good one. And now you're tossing and turning and you have another bad night because you woke up too late in the morning. The same is true for going to bed too early. You think, well, my bedtime is normally, you know, let's say it's 11 o' clock in the evening, I'm going to get to bed at 10 o' clock tonight because I had such a bad night of sleep. Resist, don't do that. Because your circadian rhythm, your natural 24 hour rhythm will not typically want you to go to bed until 11, but you get into bed at 10 and then you're wide awake and now you have another bad night of sleep. Napping we've already spoken about just takes that edge off your sleep desire. And then don't obviously try to compensate with caffeine because you'll just have more caffeine in the system, which means that following night you're going to be more alert and more awake. So it sounds strange to say, but after a bad night of sleep, stay the course, just do what you normally do. And by the way, the other tip as a strange one, many of us have a wake up alarm. Why don't we have a Tibet alarm?

You mean like an alarm that tells us time to go to bed?

Yeah, just, you know, set it for, you know, 30 minutes before bed and it's just.

And that's your wind down time.

Yeah, and that's your wind down routine. And even if it just means that two out of the seven nights a week you end up just being nudged to go to bed a little bit earlier or on time, I should say, then that is a great hack. The other thing too is I would say remove all clock faces in your bedroom. Because if you wake up and you're having a bad night of sleep, knowing what time of night is, it is, is not going to help at all. It's not going to change anything, you know, and so removal clock faces have a to bed alarm. The other thing you can do, by the way, is get ready for bed. You know, most people finish up their Netflix and then they start brushing their teeth, they'll, you know, take their makeup off, get changed instead before you sit down for television, brush your teeth, floss, get changed, get ready for bed. And then what's great is that when you feel sleepy on the couch and you turn the television off, you go straight to bed and you've already hacked back 10 or 15 minutes of extra sleep. Add that up night after night, month after month, it's like compounding interest on a loan. So even just small sort of nibbles of extra sleep can have a compounding benefit long term. Do you see? Does that make some sense?

Makes a lot of sense. And I'm assuming also, you know, what about light? Is it if there's any light in the room, making sure you have blackout shades, how does that impact you?

Great question. Yeah. Another tip that I would usually give is darkness. We are a dark deprived society in this modern era and we need darkness at night to trigger the release of a hormone called melatonin.

Yes.

So in the last hour before bed, dim down half of the lights in your house and you will be surprised at how sleepy that actually makes you feel. And you can go even further. You can dim, you know, three quarters of those lights and try and stay away from screens. The data on screens has actually taken a twist of late if you look at it. At first we thought, you know, the blue light from those LEDs was bad. And it is bad. It's the worst form of light in terms of blocking melatonin, you know, the yellows and the red wavelength of light that isn't as harsh on blocking melatonin. The cool Blue light. That's the lower sort of wavelength spectrum of light that's especially harmful to melatonin. But what we've started to realize, some great studies coming out of Australia have found that perhaps it's not so much the light, it's that these devices are activating. Those devices are designed for attention capture, correct gamification. Gamification, you know, get me on the. Activate my brain. So you are perfectly sleepy and you would be fine to get into bed and fall asleep, but because you're using the device, the device asks, sorry, acts as a masking agent and it stimulates you awake despite you underlying having a strong desire to sleep. And that's one of the reasons why those devices can have such a deleterious impact. But again, unlike some sleep folks, you know, that genie of technology is out the bottle and it's not going back in anytime soon.

It's not. Yeah.

So there's no point in me saying, you know, has sleep become an enemy of, you know, has the invasion of sleep into the. Of, sorry, technology into the bedroom, hurt our sleep? I think it has. However, I actually think that technology can become a salvation to bring us back in line with our sleep. And, you know, there's a whole separate episode we could do on sleep and technology. But so to come back to your point though, darkness at night is key. And then keeping it dark at night, try to block out any of those small little lights in your bedroom. Blackout curtains are great. If you can't accomplish that, wear an eye mask. Earplugs are great to help dissipate sound and noise interruption from a noisy environment. All of those things are great.

Okay. I love this. This is powerful. I've got a couple final questions for you. I could continue for a long time on this because I think this is fascinating, but when you're in LA next, we'll have to do another one in person.

I would love to. I'd love to sit down.

For those that want more, you've got a new podcast, the Matt Walker Podcast. And you've got an amazing book, why We Sleep Unlocking the Power of Sleep and Dreams. And I highly recommend people subscribe to your show and follow you over on social media and get the book for yourself for your friends. You're also sleep diplomat.com and Dr. Matt Walker.

You can find me, right? Yeah. At Sleep Diplomat and on Instagram, which is usually the best place to connect with me. It's Dr. Matt Walker. D R M A T T W A L K E R. Perfect.

Yes. A couple final Questions for you before we wrap things up. This is called the three truths question. Hypothetical scenario. I'd love for you to imagine it's your last day on earth, many years away from now. You've slept your way to 200 years young and done all the right things and you have accomplished all your greatest dreams in life. You've seen everything come true that you want to have come true, Matt. And for whatever reason, all of the content you've created and put out into the world, yeah, it has to go with you or it goes to another place. But no one has access to the information anymore. It's hypothetical scenario, but you have a piece of paper and a pen and you get to write down three things you know to be true. The big lessons you learned in your life that you would leave behind. And this is all we would have as information that you would leave behind. What would you say would be those three truths for you?

I would say acceptance over denial. I would say questions over advice. And I would say self compassion over self brutalization.

Those are powerful ones, very powerful.

I've probably been guilty of all of those.

I think we probably all have been individual. Yeah, probably all been guilty. And I think that's why it's so important to see the other side of the coin and how important it is to let go of those things and be more aware.

So those are still not perfect in any way, shape or form on those. But those would be it.

But you're aware, you're practicing it, so that's beautiful. I want to acknowledge you, Matt, for showing up and being obsessed with this science and this data and making this a mission of yours to learn how we can heal, learn how we can live better, longer, healthier lives and giving us the data, giving us the science, and making this your part of your life's mission to help people live better. I think it's, you know, you're the one who's saying sleep, except for oxygen, sleep is the key factor towards productivity, towards health, towards mood, towards happiness, towards longevity. So I appreciate you constantly in the, the research, constantly looking for more ways that we can optimize, especially as technology advances and more challenges and complications and distractions and poor food, nutrition and drugs come into play. Giving us the research and the science to help us hopefully make better choices with our lives. So I really acknowledge you for everything you're up to.

And I stand on the shoulders of some wonderful past, all of my colleagues and sleep scientists, and I'm just trying to do a tiny little bit to hopefully reunite humanity with the sleep that it's so desperately bereft of.

Absolutely. Absolutely. Again I want to make sure people subscribe, get the book, check you out on social media. Make sure to let Dr. Walker know what your thoughts are about this. Leave comment below over on YouTube or message him over on Instagram and Twitter if you're listening to the audio. And my final question for you is what's your definition of greatness?

Astonishing service to others.

There you have it. Dr. Matthew Walker, thank you so much for being here. I appreciate it.

Thank you so much for having me. It's just privilege and a delight to speak with you. Louis. Thank you. Learning to control your heart rate and thereby your mind using your breathing so it goes breathing, heart rate, mind in that sequence. So if your mind isn't where you want to it to be don't start with the mind start with your breathing then which will control your heart rate which will then allow.