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The Dose Transcript for September 28, 2023

Host: Brian Goldman

[Music: Theme]

BRIAN GOLDMAN: Hi, I'm Dr. Brian Goldman. Welcome to The Dose. I watched the Toronto Blue Jays of MLB's American League. You may have heard that Jays pitcher, Yusei Kikuchi, took himself out of a game against the New York Yankees because he got a cramp involving a muscle that is critical to the left-handed pitcher’s delivery.

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[baseball commentary]

FIRST MALE SPEAKER: Now, Kikuchi just grabbed the back of his shoulder right there. I'm surprised nobody has picked up on it.

SECOND MALE SPEAKER: He's going to throw a pitch. They're trying to call timeout and nobody…

BRIAN GOLDMAN: Now, later, Kikuchi explained that the muscle cramp was caused by a lack of sleep. But get this, he said he only got 11 hours of sleep the night before, instead of his usual 13 to 14 hours. That's per night. So this week, we're asking, how much sleep do I really need? Hi, Michael. Welcome to The Dose.

MICHAEL MACK: Hi, Brian. Thanks for having me.

BRIAN GOLDMAN: So what did you make of this story about Kikuchi?

MICHAEL MACK: Yeah, Mr. Kikuchi does sleep a lot, but it doesn't surprise me. The elite professional athletes tend to require more sleep on average compared to other folks. For the reason they're really exerting themselves and for body recovery to occur adequately for them, a lot of them do sleep greater than the usual average need for sleep of the general population.

BRIAN GOLDMAN: But okay, so let's have some confessions here. When was the last time you slept 13 hours in one night?

MICHAEL MACK: This past weekend. I love to sleep. It's my business, but I'm also the biggest proponent and user of sleep. And, you know, also, you know, I need to catch up on sleep during the weekend for my missed time in the weekdays.

BRIAN GOLDMAN: Well, all I can say, Michael, is good for you, because I don't think I've gotten 13 hours of sleep in three nights, let alone one night. But you are clearly the expert. I'm a chronic insomniac, so I want to hear what you have to say. But before we begin, can you please give us a hi, my name is? Tell us what you do and where you do it. Just adlib.

MICHAEL MACK: Hi, my name is Michael Mack. I'm a psychiatrist and sleep medicine specialist at the Centre for Addiction and Mental Health. I'm an assistant professor of psychiatry at the University of Toronto, and I'm the current vice president of clinical at the Canadian Sleep Society.

BRIAN GOLDMAN: Okay. We'll get to elite athletes. For those of us adults who aren't pitching for the Toronto Blue Jays, how much sleep do we need?

MICHAEL MACK: Yeah. For the average adults, the recommendation is to sleep seven to eight hours a night. And obviously, that type of sleep need changes depending on your age. As an example, newborns probably need anywhere between 14 to 17 hours of sleep. And, you know, for those of us who are parents, you'll know this quite intimately. And as a person ages from being a newborn to being an infant, sleep time generally decreases.

BRIAN GOLDMAN: So we're going to be focusing mainly on adults, I guess, ages 18 to 60. Not everyone needs the strict seven to eight hours. There's a bell curve there, isn't there? There's a spread.

MICHAEL MACK: Yeah, that's right. You know, the average would be, let's say, seven to eight, seven to nine hours for the average individual. But you're going to have people to the left of the bell curve and people to the right of the bell curve. So some people genetically need more, some people need genetically less. And, you know, we hear people brag about how little sleep they need and still function during the daytime, one of which is Winston Churchill, as is true in terms of historical figures.

BRIAN GOLDMAN: He, of course, was a napper. And certainly, I became a napper over the years. Does napping affect the seven to eight hours of sleep? Or are we talking about an aggregate, including naps?

MICHAEL MACK: And here's the thing about napping. As a general rule, it's probably best to avoid napping if you're an adult, for the reason the naps that you take during the daytime, that amount of time is taken away from your Nighttime sleep. So if you nap regularly during the daytime, that might cause insomnia symptoms at night. So maybe a problem falling asleep or staying asleep. So for most folks, we advocate for them to just sleep at Nighttime. Go to bed when you're feeling sleepy, wake up every day around the same time and avoid taking the daytime naps. But let's say by circumstance, you know, or your responsibilities, you have to have, you know, a lesser amount of sleep, how do I add to that? How do I get to the normal amount of sleep? That might mean that you would take a nap. And if you have to take a nap, we advise you to take a nap That's less than 30 minutes in length, for the reason naps that are longer than 30 minutes can cause you to wake up feeling groggy. So the shorter ones are better.

BRIAN GOLDMAN: Okay. Beyond age, what affects the amount of sleep that we need?

MICHAEL MACK: Your exertion during the daytime, whether it's mental or physical. So if a person is, you know, participating in strenuous exercise, that person will probably need a longer period of sleep at night. We know that muscles and bone are, you know, being broken down when you exercise. And that repair takes place in sleep, specifically deep sleep or slow wave sleep where your body releases the bulk of its growth hormone. And same thing with cognitive or mental exertion. You know, if you've been doing something that's mentally strenuous, you might need more sleep that night.

BRIAN GOLDMAN: So in general, if you look at the tables for the amount of sleep per age, we seem to need less sleep as we get older. But there's also a mismatch between what we're supposed to get and what we do get. Am I right about that?

MICHAEL MACK: Yeah, that's right. Maybe the latest study is looking at that topic. Up to a third of folks in North America actually don't get that seven to eight or seven to nine hours of sleep a night.

BRIAN GOLDMAN: And why is that?

MICHAEL MACK: Social factors, you know, figures into this. You know, like society's really changed in the last 50 years. Most of us have daytime responsibilities, whether it's going to work or going to school and then afterwards spending time with their family. You know, it seems that as society has progressed, our allotment of time for sleep has decreased. And some of that might factor in, you know, with technology. We know that the proliferation of LCD technologies such as, you know, the ones that we see on our laptops and our cell phone screens, that also affects sleep sometimes in a negative way. As an example, if you're using your cell phone at night, your smartphone, or using a laptop close to your bedtime, the light from your LCD screens can mimic the wavelength of light that we get from the sun. And of course, that fools your brain, tricks your brain to thinking it's daytime and then suppresses your natural melatonin secretion and thus curtailing your total sleep time.

BRIAN GOLDMAN: So I think a lot of those characteristics would apply to younger people who get less than the seven to eight hours of sleep per night that they're supposed to get. As we get older, though, we start to have other medical problems like pain. You know, I have… I've had bouts of sciatica, which have certainly affected my ability to get into a comfortable position for sleep. I guess people have osteoarthritis. What other factors might interfere with your ability to sleep as you get older?

MICHAEL MACK: Yeah. Like, you know, by virtue of ageing itself, we know that older adults progressively have a lesser ability to stay asleep and fall asleep. We know that deep… the proportion of deep sleep that people get as they age decreases. And towards age 70 and above, we actually see a reduction in REM sleep or dream sleep. And, you know, we don't totally understand the reason why. We know some of this has to do with ageing and the reduced capacity for recovery. And of course, like what you mentioned, Brian, which is, you know, an increase in the incidence of medical conditions as you age. So pain being one big culprit as to why people can’t fall asleep and stay asleep and other factors too. You know, one that affects men would be benign prostatic hypertrophy. You know, as you age, you might have to use the bathroom more in the middle of the night. And that's another reason why a person might have to, you know, wake up or, you know, have less total sleep time.

BRIAN GOLDMAN: You touched on something that I want to follow up on, and that is the quality of sleep, the type of sleep that you're getting. It's not just a strict number of hours, it's also the quality of the sleep that you're getting. Can you amplify on that?

MICHAEL MACK: Yeah. Like when we think about sleep and study it, we break it down into different sleep stages, and we determine that by reading your brainwaves. So we differentiate the stages of sleep into two umbrellas, non-REM sleep and REM sleep. REM sleep is associated with rapid eye movements. It's associated with vivid dreaming. And then specific to the quality of sleep, we like to think that a portion of non-REM sleep, what we call deep sleep or slow wave sleep or N3 sleep, that is the most restorative type of sleep that a person gets. It's a form of non-REM sleep in terms of most folks, we think that they can get up to 20% of it in terms of your total sleep time. That's the time when your brainwaves are at their slowest, the amplitude of the brainwaves are the highest, and that's the time when the body releases the bulk of its growth hormone. So when we think about muscle and bone repair, that's the stage which that occurs. And it's also responsible for memory consolidation, especially declarative memory. So, you know, memorizing what the percentage is that each stage of sleep occur, you know, memorizing facts. We like to think that that's associated with that type of deep sleep.

BRIAN GOLDMAN: When we regularly don't get enough sleep, either quantity or quality or both, what impact does that have on us?

MICHAEL MACK: Yeah, it's sort of like a two-pronged situation. You know, we know that curtailment of sleep, sleep disturbance itself is associated with increase instance of mood disorders like depression. If a person has a history of bipolar disorder, a reduction in sleep can actually flip that person to mania. We know that as cognitive impacts, people that routinely sleep fewer than six hours a night do worse on cognitive testing, looking at things like reaction time and memory. And then there's also physical effects. We know that curtailed sleep again is associated with cardiovascular illness, with an increased incidence of high blood pressure, diabetes, and even the risk of stroke and heart attack.

BRIAN GOLDMAN: So a lot of potential problems. And we're talking about too little sleep. Is there such a thing as having too much sleep?

MICHAEL MACK: It transpires that too much sleep is also… can also be unhealthy, specific to prolonged sleep. So sleeping more than nine hours a night, that's also been associated with the same cardiovascular risks as too little sleep.

BRIAN GOLDMAN: That's interesting. Do we know why?

MICHAEL MACK: There might be a connection between too much sleep and too little physical movement and exercise. It might be associated with sedentary lifestyle. That might be one reason why.

BRIAN GOLDMAN: You know, we started this conversation talking about one of the Blue Jays pitchers, Yusei Kikuchi. He's not Kevin Gorman, who's the ace of the staff, but he would still be considered an elite athlete. So what does research tell us about the amount of sleep that elite athletes need?

MICHAEL MACK: Yeah. There's been a burgeoning field of study, which is sleep and its relationship to performance in athletes. And what we see, it appears, is that there's a relationship between sleep extension and better athletic performance. And the studies look at both aerobic and anaerobic performance. Aerobic performance, one example being, let's say, a long distance run, things that require significant lung capacity, things like, you know, distance swimming. And anaerobic exercise are explosive. So they might involve things like, you know, what Kikuchi does, which is, you know, throwing a baseball with extreme speed. It appears that sleep extension improves the performance of both types of activities. And conversely, a disturbance of sleep or curtailment of sleep duration leads to worsened performance.

BRIAN GOLDMAN: You mentioned sleep extension, which sounds like something that I would pay a lot of money to obtain if I could. Can you say more about sleep extension?

MICHAEL MACK: Yeah. Like so has looked into, you know, how much sleep elite athletes think they need, it transpires that the average amount would be around, at the very least, 8.3 hours a night. You know, are they getting that? The answer is about 70% of athletes are not getting that 8.3 hours of sleep that they think that they should get. The sleep extension usually occurs one of two ways. Athletes can extend their sleep by going to sleep earlier than their usual habitual earliest of bedtime. And then for some others, they’ve added in short naps during the day. So a nap of less than 30 minutes in length. Once again, avoiding that sleep inertia, you know, the possibility of waking up feeling groggy, which is associated with longer naps.

BRIAN GOLDMAN: It sounds like elite athletes are gifted one way or another. They're outliers. You know, if they can nap and add the nap to the amount of sleep that they're supposed to be getting, then they're better off than a lot of average people like me.

MICHAEL MACK: I think for the average person, you know, the focus doesn't need to be about whether, you know, you need to extend your sleep or not. The best question that the average person can ask themselves is when I wake up, do I feel refreshed? And if that amount of sleep is seven to eight hours, then that's great. And if it's less than that but you wake up feeling refreshed, then that's fine too. So I think, you know, for the average person, just ask yourself, when I wake up, how do I feel?

BRIAN GOLDMAN: What are some of the other symptoms of chronic sleep deprivation that people will identify with?

MICHAEL MACK: Yeah. Like with chronic sleep deprivation, you're going to see a decreased cognitive capacity. Your ability to remember things is going to be impaired. Your reaction time will be longer. You might have longer and greater periods of fatigue and sleepiness during the daytime and it can affect your mood. If a person has chronic sleep deprivation, they can start feeling depressed. And we know that insomnia actually is a risk factor for suicide.

BRIAN GOLDMAN: So let's just say I'm coming to you for some advice. What is your advice for us average folks to get better sleep?

MICHAEL MACK: Yeah. The best advice is summarized as follows. I would tell the average person to wake up every day at the same time, being that having a consistent wake time stabilizes your internal body clock at Nighttime, which means better sleep and better mood. On the other hand, the time that you would choose to go to bed can differ from night to night. It really depends on what you did during the daytime. You know, as we've discussed, if you've had strenuous day cognitively or physically, you might feel sleepy earlier compared to the average day. So your bedtime doesn't have to be the same from day to day, but your wake time should be always the same. I would avoid daytime naps. And if it's absolutely imperative, then, you know, keep your naps nice and short, less than 30 minutes in length.

BRIAN GOLDMAN: What else would you recommend? You know, certainly, over the years, you know, I've accumulated a lot of tips. I wear eyeshades. I wear earplugs. I have tried white noise. I've tried green noise. What about that sort of stuff?

MICHAEL MACK: Oh, yeah. Like other tips would include things like avoiding bright lights, especially two to three hours before your bedtime. The bright light can take the form of fluorescent lighting indoors, but also from your smartphones and your laptops. And I think regular exercise definitely has been proven to improve sleep quality and mood also. So you should do that on a regular basis, maybe half an hour a day at the very least. But, you know, do avoid rigorous exercise within two hours of your bedtime, because if you exercise too close to your bedtime, that actually might prevent you from sleeping well, for the reason when you're exercising, your heart rate and blood pressure is going up. Those are the opposite factors that you need to have a good sleep. And there's other things that are out there, like maybe emerging avenues of improving sleep. One group has demonstrated that the use of weighted blankets has been shown to decrease insomnia symptoms, reduce your, you know, the time it takes for you to fall asleep and reduces the time that you're up in the middle of the night if you sleep with weighted blankets.

BRIAN GOLDMAN: What's the theory behind that?

MICHAEL MACK: Well, the idea is that for those of us who are parents, you know that swaddling babies can calm them. There's the idea that having the feeling of a weighted blanket actually increases parasympathetic activation, right? You know, that's the nervous system side that's associated with being relaxed.

BRIAN GOLDMAN: Any other emerging technologies that you want to talk about?

MICHAEL MACK: Some folks have studied sunglasses that block blue wavelength light. And as a consequence, they look like yellow sunglasses, for the reason it's the blue wavelength light that actually triggers our brain into thinking that it's daytime, which also then suppresses melatonin secretion, which is sort of the signifier as to when we should start to feel sleepy at nighttime. So for some shift workers, wearing these yellow sunglasses can facilitate better nighttime sleep.

BRIAN GOLDMAN: So that's interesting. A lot of people are using apps these days to monitor their sleep. Is that in any way helpful or relevant to what we're talking about right now?

MICHAEL MACK: Yeah. Like I think, you know, having feedback from either apps or wearable technologies can be helpful to track your sleep health. So they do a pretty good job of measuring when you fall asleep and, you know, when you wake up for the final time and how many awakenings you have in the middle of the night. What they're not good at is sleep staging. So when I see patients and they show me that, you know, according to my activity tracker, I'm having 90% light sleep, I tell them not to worry because sleep staging can't be done through the sleep trackers. They can only be done by reading your brainwaves. So they're sort of using movements and a relative absence of movement to delineate the wakefulness and sleep respectively. Having that might give you an idea of your improvements to sleep. Let's say if you're somebody that used to habitually nap during the daytime, if you take away your daytime naps, you might see an increase of your nighttime sleep if you choose to track your sleep through these technologies.

BRIAN GOLDMAN: Last question I want to ask you is a personal one. I don't have so much trouble falling asleep, but I do have trouble staying asleep. I wake up, maybe I have to go to the bathroom and then I can't get back to sleep. Any special recommendations for people like that?

MICHAEL MACK: Yeah, that's a great question. So if you're somebody that wakes up regularly in the middle of the night, one way to reduce this is actually, you know, if you find yourself up in the middle of the night and it feels like it's been a long time, don't stay in bed, for the reason if you're going to stay in bed while you're wide awake, that creates a psychological conditioning associating your bedtime with wakefulness. So what I would tell you is get up out of bed, go to a different room that's dimly lit and do something boring like a word search. In about every 15 minutes, you're going to feel that natural wave of sleepiness, that head nodding feeling that we all get if we attend a meeting after 45 minutes. And that's your cue to go back to bed. And that allows you to break that association between your bed and being awake and facilitates more continuity of sleep.

BRIAN GOLDMAN: If you are somebody who, you know, once you wake up, after a few moments, you start to have racing thoughts, is there anything that can be done to kind of quell those racing thoughts that kind of take on a life of their own and keep you awake?

MICHAEL MACK: Oh, yeah. Like we see that quite often, you know, folks that have trouble falling asleep because of racing thoughts, you know, thinking about things that worry them just before bed. Maybe there's two ways to deal with this. One is to take time during the daytime, set aside maybe 15, 20 minutes to write down all the things that worry you and then putting that sheet of paper away. So you're sort of having a predetermined worry time, after which, you're just going to not think about this subject anymore. That seems to help with minimizing ruminating about worries before bedtime. The other way to deal with this is to mentally visualize mundane things like the shape of a tree or your favourite fruit. By diverting your attention to something that's mundane and boring, you end up blocking out those racing thoughts.

BRIAN GOLDMAN: Hmm. Never heard that before. I'm going to give that a try. Dr. Michael Mack, you are a fountain of useful information. Thank you so much for coming on to The Dose and talking about how many hours of sleep we need.

MICHAEL MACK: Hey, thank you so much. I'm delighted.

BRIAN GOLDMAN: Dr. Michael Mack is a staff psychiatrist and sleep medicine specialists at the Centre for Addiction and Mental Health in Toronto and an assistant professor of psychiatry at the University of Toronto. Here's your dose of smart advice. On average, adults need seven or more hours of sleep per night. Infants, children and teens need a lot more than that, and there are specific guidelines for different age groups. Keep in mind that some adults need more than seven hours and some need less. Sleep experts aren't sure what's behind those variations. The quality of your sleep is as important as the quantity. Normal sleep is divided into four stages. The key is to progress through the four stages of the sleep cycle several times each night. Deep sleep, which begins 20 to 30 minutes after you first doze off, is the most restorative sleep. Deep sleep strengthens bones and muscles, helps prevent injuries, and helps keep the immune system functioning. It's also important in helping regulate glucose metabolism. There is some research evidence that elite athletes need and can get more sleep than the rest of us, which helps them maintain a high level of performance and recover more quickly. If you don't feel refreshed and alert when you wake up, you may not be getting enough hours or enough quality sleep. Other symptoms of poor sleep include reduced alertness, mental fogginess, irritability, slow reaction time, trouble forming new memories and nodding off. Ways to get more sleep include reducing stress, establishing sleep routines and rituals, cutting back on caffeine in the afternoon and evening, using eye masks and earplugs, getting regular exercise, eliminating screen time for an hour before bed, sleeping in a cool room, practicing sleep meditation and listening to white noise. Other tools that may help include weighted blankets and glasses that filter out blue light. Napping during the day is discouraged since it makes it harder to get enough sleep at night. If you must nap, keep it to less than 30 minutes per day. If you have topics you'd like discussed or questions answered, our email address is thedose@cbc.ca. If you like this episode, please give us a rating and review wherever you listen. This edition of The Dose was produced by Isabelle Gallant. Our senior producer is Colleen Ross. The Dose wants you to be better informed about your health. If you're looking for medical advice, see your health care provider. I'm Dr. Brian Goldman. Until your next dose.

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How much sleep do I really need? - Transcript

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