19 minute read
THE BIG SLEEP
The secrets to a restful, restorative nightime slumber
MARK ZITTER: Tonight we’re going to talk about sleep, which is something we all know a lot about. Dr. Aric Prather is a professor of psychiatry and behavioral sciences at UCSF here in San Francisco. He runs the sleep lab there, which has both clinical work—seeing patients—and research work. So we’ll benefit from both of those streams of your expertise.
So let’s get started. I’m going to go out on a limb here and say that everyone listening right now has had experience with sleep in the last 24 hours and probably just about every night of their lives as well. So we all think we know a lot about sleep, and I think we all know that we feel better if we get a good night’s sleep.
Feeling better is a great reason to get a good night’s sleep. But what are other benefits of getting enough sleep? Why should we care?
ARIC PRATHER: First I want to say thank you for having me. I’m a proud listener of The Commonwealth Club.
Sleep is such a critical part of our humanness, it’s a biological imperative. It’s as necessary as food and water and oxygen.
In fact, we can live longer without food and water than we can without sleep, in part because it provides so many critical benefits to our cognition, to our cardiovascular system, to our immune system. It makes us better people when we get sleep; we’re better partners, we’re better parents, we’re more empathetic, and we’re kind of a better version of ourselves. We’ve learned a lot in the sleep science over the last several decades, but we’re still kind of chipping away at what it is that makes sleep so special, like why we sleep. But it’s clear that if we don’t, we just can’t survive.
ZITTER: We know that from research. So what about the flip side? What are some of the downsides, besides not feeling so good, if we don’t get enough sleep?
PRATHER: If we don’t get enough sleep, we don’t feel as good. We’re more sensitive to stressors when they happen in the world. I always tell my patients that when we don’t get sleep, little things feel like big
Sleep Is Essential To
our physical and mental wellbeing and just as important as food, water and oxygen. So why do so many of us struggle to get a good night’s rest? Dr. Aric Prather shares effective techniques that he uses to help his own patients achieve healing and restorative sleep. From the November 7, 2022, program “Aric Prather: How to Get a Good Night’s Sleep.”
ARIC A. PRATHER, Professor of Psychiatry and Behavioral Sciences, University of California, San Francisco; Author, The Sleep
Prescription: Seven Days to Unlocking Your Best Rest
MARK ZITTER, Founder, Zetema Project; Member, Commonwealth Club of California Board of Governors—Moderator things to us. But also biologically, sleep is so critical. If we don’t get sufficient amounts of sleep—and this is something that’s just evolving in the science, sleep seems to be critical for helping to clear our brain of metabolites that build up throughout the day. So we’ve begun to recognize the lymphatic system is such a key piece of “clearance” within the brain. And when we don’t get sufficient amounts of sleep, that doesn’t happen as well.
I do a lot of work on the immune system, and we know that when people don’t get sufficient amounts of sleep, our immune system doesn’t seem to do as well. We’re perhaps more susceptible to infectious illnesses. We don’t respond as well to vaccines, which obviously became much more timely over the last couple of years. So sleep just plays a strong role in making our systems work better.
ZITTER: I’m assuming everyone listening to this is interested in sleep and sleeping better. Some people have big problems with sleep. But how big a problem is it? How many Americans have substantial sleep problems?
PRATHER: It’s shockingly high. The data suggest that 30 percent of Americans report insomnia symptoms regularly. If you scale that up, that’s almost 100 million Americans. So that’s a really big problem beyond just sleep disturbances. A large proportion of the population also gets what’s called insufficient amounts of sleep, getting short sleep duration.
The American Academy of Sleep Medicine recommends for adults to get at least 7 hours of sleep per night. And a lot of people aren’t getting that. What we know from the epidemiologic data, the population-level viewpoint, is that when people are in that short-sleep duration group, they’re more likely to develop cardiovascular disease, more likely to develop type 2 diabetes.
As I mentioned, we’re learning more about risk toward neurodegenerative diseases—and not to be outdone, short sleep duration is also a predictor of premature mortality.
ZITTER: Wow. So there’s a lot of Americans who aren’t getting enough sleep or are having sleep problems of some sort. Does that vary by gender, by race, by age?
PRATHER: Yeah. There are growing understandings about differences in populations. We certainly know that if we look at men and women, women tend to report worse sleep quality. Some of this might be linked to changes across the life course and perimenopause and menopause. But men tend to get less sleep in general.
And then there is something that I’m really passionate about. There’s a growing appreciation for sleep inequities within populations. So Black Americans routinely are shown to get less quality sleep compared to white counterparts, individuals that are on the lowest rung when it comes to socioeconomic status tend to get less sleep and less quality sleep.
ZITTER: Do we know why?
PRATHER: We’re learning more about it. We think there are certainly environmental factors that drive differences in sleep. So if we take racial differences, sleep is socially patterned. Where you live, work and play matters for how you sleep. So if you live in an area that has light pollution or noise pollution or more crime or less sanitation, or you to live in a more crowded area like more people per room, all of those things contribute to our ability to sleep well, our opportunity to sleep well. I’ve really approached this like a social justice issue, that everyone deserves the right to have adequate rest. Currently, it’s just not distributed evenly.
ZITTER: I think most of us have assumptions about sleep issues. I will admit that when I read your book, I thought I knew a lot about sleep, and some of the things that I believed turned out to be true, according to your book, some partially true, and some were dead wrong. So I’d like to try something. I’m going to make a couple of statements about sleep and . . . then we’ll get your expert opinion.
The first one: It’s easier to fall asleep if the room is dark than when it’s light. Is that true?
PRATHER: True, true. That is one of the key pieces of sleep hygiene. Darkness makes it easier to sleep.
ZITTER: All right, so I knew that. I knew that I got that one right.
The best temperature for sleeping is room temperature. I hope that’s true, because I don’t want to adjust my thermostat every night when I go to bed. Is it true? Is the best temperature for sleeping room temperature?
PRATHER: That’s a tricky one, because it depends on what temperature the room is. It turns out that our core body temperature has to drop as part of sleeping. And it turns out that we sleep better as a species if we’re in this range of between 60 to 68, 67 degrees Fahrenheit.
We don’t want it too hot, and for some people, that’s a little cool. So that’s where it’s important to have layers, make sure that you’re able to get within that range. The data suggests that that’s the best. So if you think room temperature is 68 degrees, maybe a little bit less than that.
ZITTER: Okay. You’re more likely to fall asleep if your room is free of clutter and distractions. Does that matter?
PRATHER: Yes. A cluttered room can be challenging, in part because you want your bed to be like a shrine to sleep. You want to set it up so that when your body gets into it, it knows what it’s supposed to do. But a lot of people—and this is certainly true of the pandemic, when, before remote working was figured out, people were using their bed as their workstation, as their TV watching place, as where they throw things. And it just makes it less special for sleep. So the more that it just serves a function of facilitating sleep, the better off people are.
ZITTER: So it’s not really a physical thing, because why should my body care if my computer is four feet away from me or not with my eyes closed, if I’m in bed? But psychologically, I may think it’s not quite a sleep environment.
PRATHER: That’s a great point. It turns out that there are a lot of environmental things that are triggers to tell us what our body is supposed to do. I always use the example of when I used to come home from the clinic, I would touch the doorknob of my apartment and I would immediately get hungry. That was because I would eat something every time I would get home. So then my body knew what was supposed to happen, even if I had just eaten it. It would be like, “I need to start making insulin.” The same is true for the bedroom and the bed. The bed is this environmental trigger that tells your body what to do.
If you’re using the bed for other things, it gets confused. It becomes less of a powerful thing that allows us to let go. Sleep is about letting go, and we need things in our environment to help us know when to do that.
ZITTER: Interesting. Here’s another one. Some people are night owls and simply need to go to sleep and get up later than others. True or not true?
PRATHER: There is circadian variation, meaning that our biological rhythms are often genetically driven, and some people are night owls, meaning that their body prefers to go to bed later and sleep in later. There are also morning larks, where people want to go to bed earlier and get up earlier. Most of us are kind of in the middle. We have a preference. But on the extreme end it can be really challenging, as you might imagine, because the world isn’t set up that way.
ZITTER: Yeah. So if you’re a night owl married to a morning lark, you really have some challenges. You have some of those, right?
PRATHER: I was just talking to someone today about their sleep problems. They were remarking [about how] there’s often the case that someone that has really severe insomnia is married to someone who sleeps like a rock. So they are constantly seeing that in their face.
I always say that, luckily, we typically choose a mate based on other characteristics than just their sleep preference. And it changes over time. So that’s just something [that is] part of the aging process.
ZITTER: Here’s one I think we’ll all find interesting. You can’t skimp on sleep all week and then catch up over the weekend. A lot of people do that. Does that work?
PRATHER: It’s definitely something that people do a lot of. I think subjectively it can often feel like people can make up some of that sleep. The tendency for someone to have this sleep and then try to shift it and make it up is often called social jetlag. We often change our rhythms, and we try to make up this time. We’re learning more about the cost of those things; that tendency to do that seems to actually put people at risk for a lot of these age-related conditions that I mentioned around short sleep duration.
Some of it’s about short sleep duration, right? You go most of the week getting less than you need and your body can’t make up all that. We deprive someone of sleep in the laboratory, say, for 24 hours, they lose 8 hours of sleep when we let them sleep. It’s not like they sleep 16 hours.
Your body can compensate, which is really important. We’re built for this as humans. Ask any parent. You can do this thing if you have little kids, but it’s not a 1-to-1 thing. I mean, there are things in place within our body to help compensate for that lost sleep.
But the data is supporting this idea that it seems to wear away at some of the biology. ZITTER: So you can partially compensate, but not not that much.
PRATHER: At least not chronically.
ZITTER: Okay. Here’s one about you and your practice. People come to your clinic because they’re having trouble sleeping. So the most frequent recommendation you make to people who come to your sleep clinic is to go to bed at the same time each night. Is it [true or] false?
PRATHER: That is not my most common recommendation. The most common thing if anybody needs to work on their sleep— again, people come to me because they’re having sleep problems—is to actually maintain a stable wake time every day. This has a lot to do with insomnia and how insomnia lives within the brain. We don’t get to choose when we fall asleep. But we do have control over what time we wake up. I always try to make the case that sleep isn’t something that we make happen. Sleep is something that comes to us, like washes over us.
We use the same amount of energy throughout the day, typically. So then you’ll tend to get sleepy around the same time each night. But if we set a known time that you need to be asleep, that actually can be distressing, right? Like you’re on the clock. Tick, tick, tick. “Oh, my gosh, why am I not asleep? I need to be asleep in 5 minutes. The doctor told me that I need to be asleep at this time.” That actually just feeds that anxiety, and that anxiety is what gets in the way of restful restorative sleep, that letting go that I mentioned before.
ZITTER: I was surprised to read in your book [where] you mentioned that probably the most common thing you see with people who have trouble sleeping is anxiety about sleeping, which is sort of a vicious cycle.
PRATHER: Yeah. Everybody has bad nights of sleep, but when you start to doubt whether you’re able to sleep—think of it as people with insomnia, they’re all often on defense. It’s like always trying to figure out what to do because sleep has become so unpredictable. So you’re really trying to put yourself in the right place at the right time just because maybe sleep will happen. I don’t want to miss it. That shift in thinking around “I’m not going to be able to sleep tonight, and if I don’t sleep, X, Y and Z is going to happen” really drives their daytime experience.
They spend a lot of effort thinking about that next night and what they should do. I have met lots of people that will cancel social engagements, because they don’t want to be away from their bedroom just in case they feel that sleepiness cue and they want to be in bed. That’s no way to live. That’s really hard.
In our treatment in our clinic, we really try to give people more confidence in their sleep by these behavioral things, as a way of really shifting their cognitions around sleep so that it’s something they don’t think about anymore, that it’s something that just happens; for people who don’t have sleep problems, they often aren’t thinking about sleep. It’s just happens.
ZITTER: Okay, next statement: If you feel drowsy in the afternoon, you should stick your head in the freezer.
PRATHER: Well, this one takes a little bit explaining. In the book I use it as an example of an exposure that we know from the science can perk people up. There’s a term called hermetic stress, which is kind of like a good stress that builds resilience within the body. Think about a polar plunge. People do that all the time and it invigorates them. Kind of something as an alternative to another cup of coffee. We’ll probably talk about caffeine a little bit.
But sticking your head in a freezer as a cold exposure might be a novel thing to do to try to get through those midday doldrums. However, you can also go outside and exercise, get a brisk [walk], get your heart pumping. What we’re really trying to do is amp up that sympathetic nervous system so that we have the alerting signals on board to get through the remainder of the day until it’s time to wind down at night.
ZITTER: Let’s talk about caffeine. Having caffeine after lunchtime can affect our sleep. What do we think?
PRATHER: I would say maybe it depends on what time we’re talking about. It turns out that caffeine has a half life—meaning how long it takes for half of it to be gone from your system—of about 6 hours. That means that if you have a double espresso at 4 p.m., at 10 p.m., you still have a single espresso in your system.
So no surprise, for many people that can be disruptive to their sleep. It’s really about ensuring that you’re not adding too many things to your system that will be alerting to impact your sleep. Caffeine is probably the biggest culprit, though. There are, of course, other substances that can muck around with our sleep. So we say not after lunch in general, just to keep people safe from doing that. But of course, if you don’t go to bed til three in the morning, maybe a little bit after lunch is fine.
ZITTER: Speaking of substances, let’s talk about alcohol. Regardless of its other health impacts, drinking alcohol can help us sleep better. What about alcohol and sleep?
PRATHER: Alcohol is a tried and true soporific. You know, people have a nightcap, and it absolutely helps people fall asleep.
ZITTER: So it is good to sleep well.
PRATHER: Well, it’s complicated, because it actually really affects the brain. It can change your sleep architecture. It suppresses what’s called rapid eye movement sleep. As a consequence, you get a big dose of deep sleep. And then a couple of hours later, you have this rapid eye movement rebound and that leads to more fragmented sleep across the night.
So it changes the quality of our sleep. In addition to that, alcohol hits on our GABA [neurotransmitter gamma-aminobutyric acid] receptors in our brain, which help facilitate relaxation. That helps give us the effect of alcohol. But alcohol doesn’t stay in your system forever. As you go throughout the night, it wanes. Your brain notices it doesn’t have this chemical creating this relaxation anymore. As a consequence, you have more fragmented sleep, less restoration.
ZITTER: So—easier to get to sleep, but harder to stay asleep.
PRATHER: Absolutely. Yeah.
ZITTER: By the way, I found that more as I age.
PRATHER: Yeah. We definitely hear that more as people age. It turns out, as we age, a lot of things get more challenging. We can’t do all the things that we used to, and we become more sensitive to certain things. I think alcohol turns out to be one of those.
ZITTER: You mentioned earlier that you’re supposed to get at least 7 hours sleep a night. We have a question from the audience that is the reverse: Is it bad to get more than 8 or 9 hours of sleep a night?
PRATHER: That’s a great question. It’s a little bit complicated. We don’t have a great understanding of sleep need at this point. We have population-level information, usually based on one question that was asked to thousands and thousands of people. Then we weighed it to make it representative of the population.
But as this viewer asks, it turns out that long sleep duration is also associated with increased risk for a lot of these negative health outcomes that I mentioned with respect to short sleep duration. Usually it’s around 10 or more hours of sleep. It depends on the study. The question is why would long sleep duration be associated with all these bad things?
There’s a couple different potential explanations which are still being figured out. One could be that what long sleep duration is really an indicator for is some early sign of disease. So if you ever get a cold or an infection, oftentimes people sleep a lot more, right? Their sleep doesn’t feel great, oftentimes, but they sleep more than they usually do. So maybe what we’re really seeing is the long sleep duration is just a proxy for something that’s going on in the body.
The other one that [scientists] have been interested in is that hypersomnia is also seen in a subtype of depression. Depression is associated with a whole bunch of negative health outcomes. So maybe what is going on is that some of these individuals are experiencing this depression. It’s really just on the pathway for the link between depression and illness.
ZITTER: Drinking warm milk before bedtime can help us fall asleep. Maybe with some cookies, too. What about more milk or some other food just before bedtime?
PRATHER: This is one that I hear a lot. We don’t have great data on this topic, but lots of people swear by it. I hear warm milk, I hear cheese, I hear bread. There may be some data to support that link. I also think that oftentimes sleep is really governed by a lot of rituals, and those rituals themselves actually cue the body to be able to sleep. I wish we had the randomized controlled trials to know about warm milk versus some warm water, perhaps. But certainly for many people, it seemed bundled in with their experience of sleep and thus somehow facilitates that experience.
ZITTER: Whatever ritual you have that makes you think sleep. That’s good. And it sounds like a lot of people’s sleep problems [are because they] don’t have rituals that perhaps [prepare them for] sleeping.
PRATHER: That’s absolutely right. Oftentimes when people have insomnia, it’s due to changes in their behavior that in the moment seem like they make a lot of sense, and they do. But they actually, in the long term, undermine how sleep works. So a good example would be when people have a bad night of sleep, they’ll try to sleep in and make up all that time.
But that can really throw in motion challenges for the following night. So if someone already has insomnia, they sleep in extra long or maybe they nap later because they don’t feel good, and then they find that they can’t fall asleep. They start worrying about the fact that they’ve lost control of their sleep and it just can feed forward. Those routines can really throw sleep off track.
ZITTER: One more more statement for us to think about: Having even a moderately stressful day can cause sleep problems. The stress leads to sleep problems.
PRATHER: That’s another great question. I will say that stress plays a critical role in most individual’s insomnia, like something happens in their life. But then it’s these changes in behavior that often perpetuate the insomnia. We do a lot of this work in our laboratory, because we’re really interested in the links between stress and sleep. They’re bi-directionally linked. We have this opportunity for interventions on both sides of the equation, right?
We know how to help with people who are stressed [with] stress management skills and meditation. We do a lot of mindfulness trials at UCSF, and so we might get an improvement in sleep as a a spillover.
But in the same way, we also know how to treat sleep, and we might give people the resources to better deal with their stress. In doing this work, we’ve been interested in the push and pull of these things. We know that stress contributes to insomnia, but does it really impact sleep in people that don’t have insomnia? What we found is that when people have bad nights of sleep, they are more sensitive to stressors during the day. So, as I mentioned earlier, little things feel like big things to them. That certainly is a true statement that we’ve seen in multiple data sets and different research groups have found.
What we’ve also found is that when people have stress, it often doesn’t really affect their sleep so much unless it’s really close to bedtime. I think part of that has to do with the fact that sleep is regulated by lots of things, like our environment, our sleep drive that builds up across the day, our circadian rhythm. So maybe these little stressors, these daily hassles that we have don’t play as big a role. Now, if you have a really big thing happen to you, then you’ll probably be thinking about it in overdrive. Difficulties with sleep. Or say you get into an argument right before bedtime, that’ll probably impact your sleep.
But I think of it as good news, because we can’t get rid of all the stress in our day and the data suggests from our group and others around the country that the relationship is much stronger from the sleep distress side than it is from the stress—the sleep side in general—in regular day-to-day people.
ZITTER: Interesting. Poor sleep causes more stress for us to be more responsive to stress.
PRATHER: Yes, yes, yes. We’re absolutely more sensitive to it.
ZITTER: So forgetting about the milk and cookies, how does diet affect sleep, or does sleep affect diet, or both?
PRATHER: We have less of an understanding about how diet affects sleep. We’re starting to learn more about whether it’s complex carbs or simple carbs that seem to improve sleep, and those trials are being done. We certainly have a really good understanding about what sleep loss does to our choicees around nutrition. All of us have probably been in a situation where we had a bad night of sleep and we had to choose between the salad and the pizza. We almost always choose the pizza. Part of it has to do with the impact of sleep loss, what it has on our reward system in our brain.
When we experience sleep loss, our reward system—our drive toward some of these things—increases and our ability to regulate decreases. So we’re like the gas is on and the break isn’t working. That ultimately leads to challenges and food preferences and actual behavior, too.
It’s certainly a really interesting area of neuroscience to think about how sleep really helps govern some of these things that are so critical to health and well-being. As the sleep field has progressed over time, it’s clear that sleep is now being considered as a pillar alongside exercise and nutrition. And that wasn’t the case even a decade ago.
ZITTER: But seeing the links is interesting. I recal something in your book about a study with supermarkets where people who had less sleep often bought food that wasn’t as good for them.
PRATHER: Yeah. Oh, man. It’s definitely one of my favorite studies ever. It was a study where they deprived people of sleep or they didn’t. Then the research group had built a grocery store and given them like X-amount of money and they could walk around. The caloric density of the food that was bought by the people that were sleep deprived was so much higher. We had seen these data around preferences and “I would do this or that.” But to actually see the behavior was really interesting and really compelling.