The Food Medic - S5 E10: How To Sleep (Better)

Episode Date: March 8, 2021

On the season finale, Dr Hazel discusses all things sleep with Dr Sophie Bostock - a Sleep Evangelist who is on a mission to help millions of people to improve their lives by unlocking the science of sleep. Sophie studied Medicine and Entrepreneurship before completing a PhD in Health Psychology at UCL. Following several years with award-winning digital medicine company, Sleepio, Sophie launched TheSleepScientist.com to provide education and coaching for clients in business, the military, healthcare and elite sport.Topics include* Why do we sleep? And why is it so important? * The 8 hour rule and can you sleep too much? * Can you make up for sleep debt on the weekend?* Tips on how to achieve a good nights sleep. * Sleep tracking devices - help or hinder sleep? * Listener Question: “If I’m a light sleeper - does that mean I’m not achieving deep sleep?”* Listener Question: “Is melatonin effective for sleep problems? Or just jet lag?”* Listener Question: “CBD is widely marketed as a sleep aid - what does the evidence say?”* Listener Question: “Relationship between food and sleep - foods we should avoid/include”* Listener Q “why do some people remember their dreams and others don’t? Is it down to sleep quality?”If you loved this episode make sure to give it a review, rating (hopefully 5 stars) and share it with your friends and family. @thefoodmedic/www.thefoodmedic.co.uk Hosted on Acast. See acast.com/privacy for more information. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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exclusions and terms apply. Instacart, groceries that over-deliver. Hello, and a very big welcome back to the Food Medic podcast. I'm your host, as always, Dr. Hazel Wallace, medical doctor, nutritionist, author and founder of The Food Medic. I am very excited for today's episode as it is on a topic that I am, and I'm sure you are too, completely fascinated by. We are going to be discussing all things sleep with Dr. Sophie Bostock. Sophie is a sleep evangelist who is on a mission to help millions of people to improve their lives by unlocking the science of sleep. Sophie studied medicine and entrepreneurship before completing a PhD in health psychology at UCL. Following

several years with award-winning digital medicine company Sleepio, Sophie launched the sleep scientist.com to provide education and coaching for clients in business, the military, healthcare and elite sport. Sophie also features as a media sleep expert for ITV This Morning and has delivered talks for TEDx and Talks at Google. This podcast episode is sponsored by Carex. More than ever, we need to be more conscious of our hand hygiene practices both inside the home and out. The new antibacterial hand and surface sanitizer spray from Carex protects against 99.99% of bacteria and viruses on the go. This sanitizer has dual purpose, safe for both hands and for use on surfaces, which allows you to feel safe when commuting to work, out doing the groceries or picking up your coffee to go. Pop it in your bag or keep it in the car,

the quick drying antibacterial spray formulation gives you peace of mind when you're out and about and don't have access to hand washing facilities. So first of all Sophie it's a pleasure to have you on the podcast. It's fantastic to meet you. Thank you. And so I listened to your podcast with Google and I was just fascinated about how much information you had to give out. And sleep is an area that I have a personal interest in, well, personally and also professionally because it affects all of my patients as well. And I think over recent years, everyone seems to be, you know, getting a bit more interested into sleep and the importance of sleep. And I think Matthew Walker's book also really brought sleep

to the forefront of our minds as one of the main pillars of our health. And so to open up the conversation, I'd first like to ask you, well, why do we sleep and why is it so important? Well, I think our understanding of sleep has changed quite a lot. We used to think about it just as something that was recovery. You know, the assumption was that we got worn out by the day and sleep brought us back up to that same level. So not needing as much sleep was sometimes seen as a sign of strength. But the science has really moved on and we now know that sleep is so much more than a rebound. It's actually nature's way of improving performance.

So the right amount helps us to become literally better versions of ourselves. For example, around learning and memory. We know that important memories are strengthened and unimportant ones are also pruned back, which frees up capacity to learn new things. And even just after one night without sleep, our ability to recall new information drops by about 40%. And we were chatting a moment ago about the immune system. Sleep actually strengthens our natural killer cells. And those are the cells that are the foot soldiers in our fight against foreign invaders, including against viruses. And overnight,

we strengthen and multiply those. And there's all sorts of other things going on. We produce growth hormone, which isn't just essential for growth, but also the repair of damaged cells. But I think probably the most important thing when we think about sleep is the link with our emotions. So our stress hormones return to a low level when we sleep. And we know that people with insomnia are at twice the risk of developing anxiety and depression in the future compared with good sleepers. But the really nice thing is that after just one night of good sleep, it really can change your perception of the world and help you feel more positive yeah and I think most of us can reflect on personal experience

of that the famous phrase that you know a good night's sleep halves most problems and I think that's so true absolutely I think we become much less overreactive to things when we've slept well we know that your self-control tends to go out of the window and you're less able to think rationally after a poor night's sleep yeah and it's not just kind of immediate problems that we see when we've lost some sleep throughout the week but it can have knock-on effects in the future in terms of our long-term health. Yes, absolutely. There've been hundreds of studies which have looked at the amount of people get and long-term health risks like weight gain and obesity, diabetes, heart disease, cognitive decline, and all of these have been linked to both the amount and quality of sleep that you get.

Yeah. And so, you know, we're often told that we should get eight hours sleep kind of as the magic number, seven to nine hours sleep. How scientifically informed is that? And is there risk of perhaps sleeping too much? I think it's pretty rigorous. I mean, every scientific study has a slightly different population, slightly different outcomes, and there are lots of different ways of measuring sleep. But the way that that recommendation was developed was by pulling together a panel of experts who reviewed hundreds of research studies, and they looked at both those acute impacts of sleep deprivation and also those longer term risks.

And their conclusion was that the vast majority of adults need seven to nine hours sleep for optimal health. But it is a bell shaped curve. So we've got most people fitting into the peak in the middle of seven to nine hours. But there's always a minority for whom a little bit less, maybe six hours, or even a little bit more might be appropriate. So there's always lots of individual variation for any characteristic like that. So try and be sensitive to how you feel during the day. I think that's probably the best way to know how much sleep you need. So if you're struggling to stay awake, or you're relying on caffeine or sugar to keep you going, or if you're struggling to stay awake or you're relying on caffeine or sugar to keep you going,

or if you're having to catch up on sleep at weekends, those are probably all signs that your week would probably get easier with a bit more sleep. But in terms of the can you sleep too much, that's a really interesting one. And it could be that sleeping too long could be a sign of an underlying illness, for example, depression or infection. So we're still not really sure whether the increased risks of things like early mortality or heart disease are because we're getting too much sleep or because of that underlying health problem. But certainly for older adults in particular, sleeping for more than nine hours seems to be associated with poorer health outcomes. Okay. And you mentioned kind of catching up on sleep on the weekend, and this is something I'm absolutely guilty of. But can you make up for the sleep debt in the week

over the weekend? I think it probably depends how severe that sleep debt is. So if we're running a little bit short of sleep, a lie-in for an hour or so at the weekend is a pretty good bet. But if you've only been surviving on four or five hours sleep all week and your natural sleep need is closer to seven or eight, then most people can't actually pay that back in one Sunday morning lie-in. And the problem that you hit when you move the timing of your sleep by over an hour within 24 hours is that your internal body clocks, which control your sleep-wake cycles, can get quite confused. And you get this phenomenon called social jet lag, which describes the voluntary shifts of this sleep-wake pattern, which can cause the same symptoms as jet lag. I think those symptoms are quite familiar to me on a Monday morning. Yeah it's like you're flying in from Tehran every

Monday morning if you've had a really long lie-in during the weekend so you know the ideal thing is if you can just carve out just that little bit more time for sleep during the week even if it's only 20 minutes that will add up over the course of the week and hopefully give you less to catch up on yeah absolutely and so one of the things I'm actually really good at it sounds like I'm making this more of a formal consultation for myself but um hopefully these points will apply for other people is I know how much sleep I should be getting and I'm very good at getting into bed but sometimes I struggle with actually falling asleep and also my sleep quality and so what tips do you have to achieve a good quality night's sleep? So a good night's sleep actually starts

first thing in the morning and one of the things that people have struggled with in that pandemic era is a lack of routine. So often as you can, try and wake up at the same time during the week and at weekends. And so this really helps to keep your internal timekeepers aligned with each other and actually gives you more energy during the day. It also means that your body will get better at anticipating sleep at night. So if you have a similar bedtime, around about an hour and a half or two hours before bed, your brain starts to produce melatonin, which is the hormone that signals that it's nighttime. And that helps kind of get the brain and body ready for a restful sleep. But I do recognize that there are a lot of shift workers out there who can't wake up the same time every day. So they have to rely on probably the second most powerful signal to the body clock, and that's light. So if

you want to feel more alert, get outside. Natural daylight has an intensity that's thousands of times greater for the kind of master clock in your brain than electric light. So if you're working from home, always work by a window. And at night, try and dim the lights, use side lights, or night shift mode on your tech, or ideally, keep technology out of the bedroom. Because it does two things. You've got the blue wavelength light, which suppresses the melatonin. But probably the more important aspect is that using your phone, which might be the device that you use at work, can be quite stressful. It's quite arousing. There's always more things to look at, particularly if you are a little bit anxious before bed, your brain is craving more information.

And the more tired you get, the harder it is to switch off. I think a lot of people have probably found that. So if you make your decision about when you're going to switch off earlier on in the day, set yourself an alarm like an hour before you actually want to fall asleep. And that's the time that you switch off your phone and leave it outside of the bedroom, out of temptation's way. And when it comes to kind of having devices in the bedroom, I know a lot of people read on their Kindle. Is that going to be detrimental from a kind of melatonin production point of view? Yeah, Kindles don't give out quite as much light intensity as certainly using your phone or a laptop. But there's still a difference between reading on an electronic device and a kind of good old fashioned paper book.

If you're on a machine that's got lots of links, there is this cognitive cost. Even when you don't click on a link, your brain is having to decide, OK, what am I going to do next? So almost reducing the number of options can be very helpful. you don't click on a link, your brain is having to decide, okay, what am I going to do next? So almost reducing the number of options can be very helpful. But I think a lot of people, if you're using a Kindle and you're not experiencing any difficulties with your sleep, I'm not saying that you need to change that. That probably works for you. And one of the most important things about preparing for bed is that it feels familiar. Our brains hate uncertainty. One of the reasons for the corona-somnia around the pandemic has just been this sense that we're in a situation which is uncontrollable and new, and that can spike our levels of stress hormones.

So before bed, the ideal thing is to have a familiar routine. In the same way that parents will try and have a wind down for their kids, adults can also benefit from having a couple of things that you do each night that help prepare you for sleep. I completely agree with that last one. And then when it comes to kind of tracking how much sleep that we're getting, I'm sure most people don't really take note of how many hours they're getting. But smartwatches and things like whoops that track not just kind of heart rate and everything else, but also your sleep and the quality of your sleep. How useful are they? And is this something that we should all be tapping into more of? I think it's a really interesting one. And there are definitely pros and cons. And I say this as someone who's worn a smartwatch for some time, and I use it to track exercise. I don't look at it too much for sleep, and it never really

worried me. But I like the fact that I can track the times that I'm getting up, the times that I'm falling asleep, so that if something is a little bit out of whack, I can look back at that data. But I've also experienced the downside. So I recently bought an Aura Ring, which is perhaps one of the newest, more accurate trackers for sleep. But it's not very well correlated with what I'm getting on the smartwatch. So we know that most trackers are probably only 40 to 70% accurate versus kind of lab studies when it comes to the different stages of sleep that you're in. But I think the second downside is anxiety. Because I know that I've got this slightly more accurate device, it's actually started to worry me. Oh, you know, what does the tracker say? And there is this condition known as

orthosomnia where your obsession with the perfect night's sleep actually gets in the way so if you start to experience that what I've decided to do is just not look at the data for a while I'm going to try and keep wearing the tracker because I'm really interested but just leave it for a few weeks and not look and then hopefully once I just take it for a few weeks and not look. And then hopefully, once I just take it for granted, it will become more useful. Yeah, I think that's the reason why I don't really track my sleep. I do wear smart watches for kind of fitness tracking and things like that. But I don't wear it to bed. And I think that's also because I think I've that tendency to become really obsessed with the data. And I don't want to tear apart a good routine

that I already have. I think that's really sensible and I often if I'm working with someone who's really trying to improve their sleep actually one of the most useful tools is a pen and paper diary and the reason that you don't have to have this objective data from a tracker is that actually the most important measure of your sleep quality is how you feel during the day. So if you feel that you've had a good night's sleep and you haven't been bothered overnight, then quite frankly, that's the most important outcome to track. So if you don't wear one, I'm definitely not saying that you need one. If you want to test out which things influence your sleep then a pen and paper diary and kind of keeping a note of new routines can also be

really helpful tool yeah and um so when you were coming on the podcast obviously I had my own list of questions but I also asked everyone on Instagram if they had any questions and there were so many so so many and I think like I said earlier we're all very interested in sleep because it's something that we all do and have to do and so there's a couple of questions that were sent in that I'm going to run through if you don't mind and the first one was if I'm a light sleeper does that mean I'm not achieving deep sleep and what does this mean? Okay so the answer would be not necessarily we all sleep in cycles of progressively deeper sleep and although

trackers might only talk about two or three stages sleep scientists would usually talk about some non-REM sleep so stages one two and three and REM sleep. And we cycle through five or six of these cycles during the night. Everyone will have brief periods of wakefulness every 90 to 120 minutes between these sleep cycles. Now, sometimes these brief periods of wakefulness are so short we don't really notice. We certainly don't remember them in the morning. But often when we start to become a little bit anxious about our sleep, simply waking up during the night feels like it's a cause for anxiety. Now most people have more deep sleep in the first part of the night and more REM sleep in the second part of the night.

So if you're waking up in the second part of the night. So if you're waking up in the second part of the night, doesn't necessarily mean that you haven't already had a great bout of deep sleep. But it's certainly in that second half of the night with a higher proportion of REM sleep, that you're going to be more vulnerable to waking up because of noise, because of changes in temperature or movement. So yeah, if you're waking up, don't worry. It doesn't necessarily mean that's messed up your entire night's sleep. It's perfectly natural part of sleep. I think a lot of people find that reassuring. And I know I'm a light sleeper, or I feel like I'm a light sleeper. And also, you're not going to remember when you're

having those moments of deep sleep because absolutely not and so the next question is is melatonin effective for sleep problems so we spoke about melatonin that producing it naturally in our bodies but you can get it in a supplement which people typically take for jet lag yes that's right so in this country you have to be prescribed jet lag for specific problems whereas Whereas in America and a lot of other countries, you can buy it over the counter like a vitamin. And it is a natural hormone and it has some pretty powerful effects as an antioxidant. And it's very important for regulating these circadian internal rhythms. But it actually, as a sedative, it's very weak. So on average, if you're suffering with a sleep problem,

it might make you fall asleep seven minutes faster, on average increasing sleep time by about 20 minutes. So it's not huge effects. So in this country, melatonin is usually prescribed for people who have difficulty sleeping at the right time rather than for insomnia. And the exceptions might be for the elderly who have a lower natural production of melatonin. But if you are worried about your sleep and you're consistently having problems getting to sleep or waking up too early in the morning, then the number one treatment is an approach called cognitive behavioral therapy for insomnia. And that involves tackling the negative thoughts about sleep and the unhelpful behaviors which can keep it going yeah and we

often use the word insomnia quite like slightly in that like oh yeah i'm you know suffering from insomnia at the moment but what actually is the definition for insomnia so that people know kind of in their head whether it warrants a discussion with their doctor? Yeah that's a really good point because I think if you look up the dictionary definition insomnia is usually just called sleep problems but in order to be sort of classified diagnosed with insomnia disorder the usual definition is a difficulty falling asleep waking up in the early hours of the morning or waking up feeling unrefreshed for at least three nights a week for three months or more, despite adequate opportunity for sleep. And this sleep problem has a negative impact on daytime function. So that's quite a long definition, but I think the important parts are, you know, if you're a parent of young children and you're struggling to sleep because of that,

it's probably not insomnia. You don't really have an adequate opportunity for sleep. Unfortunately, you just need to catch up where you can. But also it's about the impact that it has on you day to day. So if you actually are only sleeping for six hours a night but you're feeling pretty good then don't let that worry you that might well be your sleep need but at the point where you're having difficulty coping with with work with relationships if lack of sleep is getting on top of you that's the time to go and seek help okay that's good and so coming on to the next question um so following on from melatonin as a supplement to cbd which is widely available now on the high street for multiple kind of ailments including sleep and other kind of anxiety issues what does

the evidence say for CBD in sleep? Well, it's a tricky one. I mean, CBD does seem to be marketed as a bit of a panacea for lots of things. And there's no doubt that at least anecdotally, people will report that it can reduce anxiety and pain. And there's some supportive evidence for that. But given the worry about not sleeping is one of the major barriers interfering with sleep, simply handing someone a smarty or placebo can actually help them fall asleep 10 minutes faster and stay asleep half an hour longer. So in order to verify that CBD oil is effective against sleep, and this is the same case for any kind of over-the-counter remedy

what we really want is a big trial where we compare people who took the placebo with people who took the intervention that we're interested in and ideally we then also look in the lab to see whether there was really an improvement in objective sleep quality. And I know that there's at least one trial for CBD extract recruiting at the moment, but I haven't seen any results yet. So I think the jury is still out. Doesn't seem to have any harmful effects that I know of, but we don't know the long-term effects. So, you know, maybe a bit of trial and trial and error yeah i agree and also with um anything that's marketed as a food supplement which i'm pretty sure of cbd would come under unless they're making any medicinal claims there can be a lot of variation in terms of how it's regulated and

the formulation and things like that so for people thinking about it make sure you're getting it from a credible source yeah i think that's really important actually that's the same for melatonin because i know that although you're not supposed to be able to buy over the counter here a lot of people actually buy on the internet and there was a study that came out not that long ago that actually said that 70 of the over-the-counter melatonin was more than 10% out in terms of the actual concentration of melatonin that was in any individual pill. And with melatonin, you don't want to actually take too much. It seems to be more effective in the lower doses, around 0.3 to 3 milligrams. And any more than that, it could actually be that the receptors for melatonin get less effective. So

be very cautious about dosing of those kind of over-the-counter products very important and the next question is the relationship between food and sleep and whether there's any foods that they should avoid or include i was thinking about this so this is a bit of a jigsaw and we've probably only got some of the edge pieces of our jigsaw right now. There's a lot that we don't know about food and sleep, but some really interesting research coming out at the moment. So I'm sure we'll learn a lot more. In 2019, there was a large study that came out showing that those people who consume a more Mediterranean style diet, so you know, plenty

of fresh fruit and vegetables, oily fish, nuts and seeds, unprocessed foods, they in a large population tend to have better sleep. And then that was followed up with studies in the lab, which controlled the amount of protein and fiber that people got and found that meals high in protein and fiber were associated with better sleep than meals that were high in unsaturated fats and sugars. So at a macro level, it seems that the good news is it's the same advice that we would give for most health outcomes, that you want a nice diverse range of foods as natural as possible and i think because sleep and mood are so closely affected where we're starting to see that a good diet can help support the microbiome and can reduce inflammation and improve mood all of those things will also have

a positive impact on sleep. So I don't have all the answers. But I think the general pattern is that healthy diets are gonna be good for sleep. Yeah, and I would agree with that. But I guess, from a food avoidance point of view, the things that pop up in my head are just caffeine, and any stimulants. And I think a lot of people aren't aware that caffeine isn't just in coffee and tea but you can find it in lots of other things like chocolate or even hot chocolate in flu tablets yeah absolutely in weird and wonderful places yeah i think it's the cold and flu remedies that get people because if you don't have a sort of night formulation for

those then taking one before bed to try and reduce your symptoms can actually keep you awake at night and a lot of them actually if you're taking a liquid they sometimes have added sugar as well which can disturb you before sleep I used to be a massive fan of hot chocolate before bed but I regret to say that I did work out it did definitely interfere with my sleep if I had it within an hour of falling asleep so if you can enjoy your hot chocolate maybe just a little bit earlier in the evening yeah and so what would you typically advise for kind of a caffeine cut off time because there's lots of different recommendations based on the half-life of caffeine yeah so the half-life of caffeine varies a lot from person to person so average, it's probably about five or six hours. But there'll be some people who metabolize caffeine much faster.

We know there's a genetic basis for that. So you might feel that actually having a cup of coffee late in the evening doesn't affect your sleep. Now, you might be right, but caffeine could still be interfering with your sleep in a way that you don't recognize so when we talk about those sleep cycles what we know from lab studies is that caffeine tends to disrupt deeper sleep and it's associated with more kind of micro arousals more little waking periods during the night so i always recommend if people are consuming caffeine after say two o'clock in the afternoon, and they're doing that on a regular basis, maybe just experiment for a couple of weeks with cutting out the afternoon caffeine and see whether it has an impact on your

sleep. But if you are a heavy caffeine consumer, don't suddenly go cold turkey it is a drug we build up a tolerance and a dependence so if you suddenly stop then it can actually cause sleeplessness and also sort of irritability and headaches yeah totally with you on that one and the final question is actually something i'm really interested in is why do some people remember their dreams and others don't? Is it all down to sleep quality? Great question. Again, it might not be down to sleep quality, it might be down to timing. So when we talked earlier about those sleep stages, I said you get more REM or rapid eye movement sleep in the second part of the night. So we get more of that in the mornings. Now, during the pandemic, because a lot of people haven't had to set an alarm, they've been waking up more naturally

from sleep. And REM seems to be the stage where it's quite natural to wake from. It's a pretty light phase of sleep. And we're most likely to remember our dreams when we wake from REM sleep. And we typically remember dreams around about 70% of the time. But certainly if you've got more intensive dreams, and we know that stress can cause more vivid and intensive dreams, then they might well be more memorable. So it could be down to stress, which could affect sleep quality, but it's probably also down to timing okay wonderful well that was a really interesting conversation and I would love to keep and speak to you a little bit longer but I'm sure we can bring you back for well hopefully we can bring you back for a second episode in

future that'll be wonderful it's so nice to meet you and thank you very much for doing a bit of sleep evangelism and getting the message out there wonderful and if people want to learn more about what you're doing or any other things that you're talking about where's the best place to find my website is the sleep scientist.com or i'm on twitter and instagram at dr sophie bostock well i'm sure everyone will be interested in finding it more about what you're talking about um so thank you for joining the podcast and hopefully we'll speak to you soon. Okay everyone that was Sophie I hope that you learned just as much as I did listening to that

episode this episode is actually our season finale. Five seasons, hey? It's been a pleasure speaking to you every week and I'm absolutely already thinking about the next season, so don't worry. But I think I will take a little break because I'm still working quite a lot at the hospital, looking after COVID patients and I guess let's just say I need a day off. On that note, I hope you are all doing really well

and I look forward to the day when we can reconnect in real life. day off. On that note, I hope you are all doing really well and I look forward to the day when we can reconnect in real life. Until then, stay safe and see you soon.