BITESIZE | How to Sleep Better, Get More Energy & Improve Your Mental Wellbeing | Dr Kristen Holmes #655

0:01Welcome to Feel Better Live More Bite Size, your weekly dose of positivity and optimism to get you ready for the weekend. Before we get into the clip, I'm really excited to share that I'm bringing my Thrive Tour, Transform Your Health and Happiness to Canada and Europe this September and November. It's a live, interactive, uplifting evening that over 20 ,000 people came to last year across the UK and Australia. I'll be sharing powerful stories, life-changing insights and simple tools that will inspire you to feel better, think clearer and live with more intention and joy. Tickets are on sale now at drchatterjee.com forward slash live.

0:49I really hope that you can join me. Today's clip is from episode 479 of the podcast With Dr. Kristen Holmes Global Head of Human Performance And Principal Scientist at WHOOP In this clip, we discuss practical strategies For harmonizing our circadian rhythms In the context of modern life And Kristen explains how factors like late meals And irregular routines Can disrupt your body's natural rhythms And share some simple changes that can make a real difference. What you said about dopamine was really interesting. You mentioned that if we are regularly up looking at lights between 11pm and 4am, then our dopaminergic system doesn't work as well the following day.

1:39Now that has some quite profound implications. Your motivation, your ability, your drive, your willingness to do the things that are required of you are going to be affected by that. So you might think you have no focus. You can't resist temptation. You don't have passion. You may think that that's who you are. That's your personality. But maybe it ain't your personality. Maybe it's a consequence of the fact that you were viewing light at midnight. Yeah. The timing of light exposure on mood and brain circuits, right? It's a beautiful paper. It was published in 2017. And basically, you know, what it said is that when we're viewing light between 11 p.m.

2:22and 4 a.m., your dopamine system, motivation, reward just doesn't work as well as it would have if you didn't view light between 11 p.m. and 4 a.m. And of course, if you're doing that, you know, once every now and again, not a big deal. But if you're chronically viewing light between 11 p.m. and 4 a.m., which is probably 70 % of the world's population at this point, like a lot of folks are getting light to the eyes, which is, you know, confusing the control center of the brain saying we're supposed to be awake, which is then telling all of the clocks in the body that it's time to be awake at times when, again, they're not programmed to be awake.

2:59They're not programmed to be, you know, firing, right? So again, this puts enormous stress on the system. So I think studies like that tell us, okay, there's something that we need to protect this timeframe. This is a time when we are not supposed to be active and awake, right? And so we think about sleep, for example, right? Sleep doesn't have a circadian rhythm, but it's an output of the circadian clock, right? So it's our daytime behaviors that dictate our ability to fall asleep and stay asleep and get that beautiful restorative night's sleep, right? But we're not really coached on what are the behaviors that actually create this beautiful night's sleep, right?

3:46We might talk about our sleep hygiene, which is very important, right? But unless our circadian rhythms are aligned, sleep is gonna be very difficult. And I think that's one of the biggest problems in modernity. A lot of this is because we're living in a world where we have access to light 24-7, we have access to food 24-7. And as a result, we're creating just a lot of stress on our system. And this manifests, of course, in things like our alertness and our ability to attend to the things that matter to us during the day, but it really, really impacts our sleep at night. Yeah, it's really interesting there.

4:23You mentioned that we have this 24-7 access now to light and food. And there's quite a beautiful contrast there between, you know, constant access and the rhythmical nature of our bodies, right? We're not meant to have that constancy of access to these things, right? We're meant to eat at certain times. We're meant to see light at certain times. And until very recently, that is what we would have done. And it's this kind of mismatch, isn't there? And it's, you know, are you saying that everyone has an internal rhythm that has presumably been set in some way based upon their lifestyle and the way they're living.

5:09But ultimately, it is internal. And our job, therefore, is to have external behaviors in our life that match that internal rhythm as much as we possibly can. Yeah, that's exactly right. And so circadian rhythms, very simply are the physical, mental, and behavioral processes that are happening over a 24-hour cycle. And when we are viewing light at a phase of the natural light-dark cycle, that puts enormous stress on our body. So we know this as, you know, viewing light at night, for example, after the sun sets, right? Or not getting enough light in the morning as the sun is coming up. So this basically confuses our system in that our internal clocks are become disorganized or don't quite know what to do.

6:05And this creates misalignment. And I think where we go a little wrong is I think we believe that there is enormous variability talking about the general healthy population in terms of our internal preferences. And indeed, when you put folks like us on a mountain with no electricity, we're all going to fall asleep within a half an hour of each other. And modernity has created an opportunity for us to be awake at 2 a.m. But it doesn't mean just because our system has adapted to it does not mean it's good for us. Yeah. What you said about we're not as varied as we might think. I'm so happy to hear you say that.

6:53You know, night owl, morning lark, I know they talk about chronotypes. It just doesn't fit with what I've seen. I've had patients who swear to me that they're night owls, swear to me. I say, okay, look, this is the consequence at the moment of you being a night owl. You know, would you like to change that? A lot of them will say, okay, but is it possible? I said, okay, well, let's just try for a couple of weeks, you know, changing a few things, light exposure in the evening being a huge one. Let's cut that out as much as we can. Let's get your dinner a bit earlier. Let's get you up early and get you outside.

7:28Right. It is amazing how many night owls suddenly say, oh, I'm doing really well as a morning lark. Now, I can't say that that's for every single person. Right. And I recognize that many sleep experts are saying that there are these chronotypes. But as you say, those studies where you go out camping or they go out to the mountains. When that happens and we're removed from artificial light, it all starts to sync up a bit better, doesn't it? It really does. And when people are trying to incorporate a more stable sleep-wake time, the most important thing is to wake up at the same time every day and view light.

8:09Even if it means potentially having a bit of a shorter sleep, that same wake up time is absolutely critical for setting your circadian rhythm, right? And dropping that melatonin at the time that you need to, right, to fall asleep and stay asleep. That's like when we talk about the coaching piece of circadian alignment, that's where you start. You wake up if you know, all right, I want to wake up at seven. Literally, as soon as you wake up, get yourself out of bed and get out into the morning sunlight or the morning natural light. It doesn't have to be sunny out, but just you want to get out in a natural light.

8:42You want to look up at the sky for at least five to 10 minutes and then go about your day, right? That's going to help set your circadian rhythm. Now, there are other behaviors that help entrain our circadian rhythm. So the timing of our meals, okay? So when we're eating our food, when we are active and social, when we go to bed, when we wake up. we want to try to align these behaviors with the natural light dark cycle so when we're supposed to be active and eating and sleeping we want to try to do that in a way that's aligned with kind of these natural environmental cues and when our circadian rhythms are disrupted as they are for so many people these days just shed a light on some of those consequences so that everyone listening can really understand it's not just about feeling good in the moment.

9:36Of course, it will help you feel good and give you more energy and more focus. But there are some quite serious long-term consequences, aren't there, when we have misaligned circadian rhythms? There are. We know that there's an increased risk of metabolic disorders and metabolic dysfunction. We know that there is not a single mental health disorder that circadian rhythm disruption doesn't touch. So if we are chronically misaligned, our internal system becomes very confused. And this cellular miscommunication is really, I think, the basis of most disease and frankly aging. And so the behaviors that have transformed my life are democratically available and free.

10:28I've personally been able to shift my circadian rhythm to an optimal kind of zone. And I have seen in my own experience, you know, as a coach, I was, you know, very much a night owl, you know, like I was cutting film, like late into the night, I was sending emails, I was doing all sorts of stuff during the night. And, and I can see now that I had just literally adapted to a lower level of functioning. And I know this because like, I didn't even know what I was leaving on the table. Like it was just like, it's one of those moments where you're like, you know, I thought I was being so productive and I, and I was by all intents and purposes, very successful, you know, but when I look back on like my health, I was a mess.

11:13It has, it's completely transformed my life, aligning my circadian rhythms. That is really empowering for people who think that the way that they feel right now is the way they have to stay. And it is simply not true. You can change any time you want. Yes, for some people, it's harder than others. It can be challenging for people in different jobs and different points in their life. but if possible you're saying you know what can i do what choices can i make to harmonize my circadian rhythm in the context of my life as much as i can and with shift workers it can be more challenging i know you you did a series of beautiful instagram videos um which i would direct people to if they they want to know your views on this right and i think that's something we really need to look at as as societies what you know is there a way to change that what can we do to help them.

12:06So we'll come back to that. But actually, a lot of the time, it's not as hard as we think. We don't necessarily need a huge lifestyle overhaul. A few simple things done consistently really very quickly start to move the needle. So understanding that we're all different, you're pretty confident that you can make a recommendation about sleep wait time, about eating windows, about alcohol, like some universal recommendations for people. let's talk about alcohol what have you seen in the data did you say food was worse than alcohol for impacting our circadian rhythms second to alcohol yeah and I think like what's tough about alcohol is like it's not just impacting you the day after it has like a five day tail wow yeah so okay you're saying from the data you've seen and you're measuring people's heart rate variability and their load and their recovery.

13:05Their respiratory rate, their activity levels. So heart variability is an incredible proxy for just our mental and physical health resilience. Incredible proxy for that. Okay, so what are we talking here? Because let's say someone has two glasses of wine, and they feel that they were up a few times at night, they have a bit of a headache the next day, they're craving a bit more caffeine, they're extra hungry, but they decide to compensate. You know what? Today wasn't good. I'm going to go to bed early tonight, eat early, not have any alcohol and they then get a good night's sleep the following day.

13:42I think most people would feel that they're back to normal the next day. It sounds like you're saying from the data that that's simply not the case for most people. Right. They probably feel better but physiologically, they're not back to their baseline. Wow. So if they're reporting drinking two plus drinks, okay, so two or more drinks, it takes on average, five days to return to your baseline. Wow. I know. On average, of course, means that for some people, that may be six or seven days, and someone else, it could be three days, but that is still... Exactly. Just average across, you know, hundreds of thousands.

14:27I mean, at this point, millions, you know, of data sets, right over you know the course of the time folks have been on on the platform yeah it's the average two plus drinks average is five days to return to baseline and again yeah it could be two days for some seven days for others but this is where the problem lies right like you basically inside that window of five days you could be having more drinks right and and so you just keep pushing then that's basically what we see is, you know, folks who have, you know, history of, you know, pretty, you know, lots of alcohol consumption, they come onto the platform with very low heart variability.

15:08Wow. Yeah. We've all got a different tolerance level to alcohol. Okay. So from the data that you've seen, are there people out there who can maybe have a small glass of wine or half a beer in the evening and it not impact their sleep? Yeah. I mean, I think the key is to make it as far away from the time you attend to sleep as possible. That's where it just kind of seems to wash away and not impact your sleep. But I can say that, you know, from what I've seen in our data, you know, which is massive amounts of data at this point, it appears that no amount of alcohol is good for your resting physiology.

16:02Okay, thank you for sharing that. Okay, so I mean, that's pretty clear on your view on alcohol and what it's doing to us. It's so hard seeing the data. It's really striking. It's very hard for me to have any other point of view because I see it so black and white, clear as day. I think I saw that also when I was wearing a tracker. And I think I also from recollection saw that, wow, this is what a glass of wine is doing to your sleep. And once you've seen it, and I guess some people need to see it over and over again. But for me, I saw it to go, okay, I get it now. I can see what's happening. I can feel it subjectively and I can see it in the data objectively.

16:45So both of those things together are sending me a strong signal. Now, I believe that you think a close second to sleep wait time is a regular eating window. Is that still the case? And if so, what is your advice and what are your recommendations? Right. Okay. So there's a couple of things with the timing of your eating. So we see at population level, it is second only to alcohol in terms of its ability to disrupt our sleep and markers of recovery. So when I say markers of recovery, I'm referring to heart variability, I'm referring to resting heart rate, respiratory rate. These are kind of our markers of recovery.

17:23And then sleep, referring to our ability to get into these deeper stages of sleep. So REM and slowly sleep and minimizing our awake time. We're going to have light sleep. That's totally normal and desirable. It's important. There are things, really important things happening during light sleep, but we want to have about, you know, 40 % of the time that we're spending in bed, we want to be in these deeper stages to restore. So the only thing that moves around our sleep more than alcohol is a late meal. And there's just no question that it has a negative impact on recovery and sleep. So for someone who, let's say, can't afford WHOOP and is like, okay, I want to implement stuff from what you have learned from all that data, but I can't go on that platform myself.

18:08Are there any consistencies as to food timing in the evening and its impact on sleep? Some people are going to be more tolerable to a late meal than others, but can you make a generalized recommendation based upon what you've seen? 100%. So, you know, there's lots of other kind of external literature that supports this as well. So this isn't, you know, just our research. But what we've seen is that, and to become not a nutritionist, I can just talk about the timing of things as someone who studies circadian rhythms. But once you fall asleep, what's happening mechanistically is you have a competition, right, between digestion and sleep.

18:48They can't do both at the same time, right? You're still going to fall asleep, but you're not going to be, it's kind of like alcohol. You're asleep, but you're not in these deeper stages of sleep. So that, and that's what we see in the data. We see that these late meals are compromising deeper stages of sleep. People are spending more time in light sleep by the tune of 30 to 50 minutes. So this is like meaningful amount of time awake, okay? And an average decrease in sleep efficiency by up to 17 % when folks are reporting late meals. Well, it's like wild, right? So food within two-hour bedtime.

19:27So the recommendation is you want to try to back up your mealtime so you're giving at least a two-hour buffer from your last calorie to when you intend to sleep. So that's a really big piece to this whole puzzle of also being able to maintain sleep consistency, right? Different foods will potentially impair our ability to fall asleep. That said, I did a study with 700 collegiate athletes where we looked at pre-sleep feeding. And it looks like a bolus of protein that's bioavailable is not really going to impact your ability to fall asleep and stay asleep. I think it's if we're having that big Indian meal a couple hours before that, that that's the one that's going to like kind of hit us hard.

20:18I think if people are eating, you know, low glycemic kind of foods, it probably is less important, right? I think it's really if we're just eating really fatty, high carbohydrate kind of foods, you know, we're over fueling. I think that's when it becomes problematic eating later in the day. But I do think if we're eating really cleanly and, you know, we're keeping kind of our blood sugar at bay, you know, I don't think that that's going to have a huge impact on sleep and recovery. So I do agree that there's variability. Yeah, that's really interesting. So I agree. So on a personal level, a few years ago, I did buy an aura ring.

21:04I found that I learned within six weeks what it was going to teach me. And one of the key things I still remember was a late dinner massively impacted the quality of my sleep. And I could see it on the data there. So here's the problem, right? Here's the problem these days is that you may want to live in perfect circadian alignment, but society isn't really set up to support that, right? So for me, sitting down with my wife and children at the end of the day is quite an important family moment, right? So if you have a lighter meal, let's say you do eat with your family, this is what I do sometimes.

21:44I'll have a soup or a bone broth in the evening. So it's a lighter meal, even though I'm having it maybe closer to bedtime than I would want. So it's going to be easier to digest 100 you know are there's a phase relationship right and and dr samar hatar um one of mine you know uh i just love him he's done incredible research in the area of circadian um physiology circadian biology but um he always he says that there's a phase relationship you know between our activity our meals our sleep um you know when we view light and i think to ignore these relationships really comes at an enormous cost, you know, to our health and our functioning.

22:27So I think we have to respect this relationship. And, you know, I don't think there's a single reason why we shouldn't try to optimize for it, you know? And I think like kind of goes back to just reconfiguring your family a little bit, you know, and I have a couple of teenagers and And we just have kind of reorientated ourself to be able to be more aligned with this natural light dark cycle. And, you know, but I think we have oftentimes with our partner, a lot of these like kind of hidden commitments that really, I think, pull us a little bit further away from maybe our ability to kind of show up in the world as we want to.

23:08And maybe that's that glass of wine at nine o 'clock or 10 o 'clock or, you know, that we have regularly. And, you know, thinking about, okay, maybe I can, knowing I want to maybe make some of these changes, maybe we can go on a walk instead. Or, you know, how do you kind of replace some of these behaviors that are getting in the way? And I think, so I think when folks maybe hear this conversation or like, it's easy to get a little overwhelmed because they're thinking about all these commitments that they have with their partner and their family that kind of don't align with this way of living.

23:43but it's just a matter of, you know, just reconfiguring. Yeah, that's a great point. So zooming out, it's this theme throughout this conversation that we have a circadian rhythm. It's important as much as we can, and some people are going to struggle for sure, that we match those external behaviors to our internal circadian rhythms. We can use a variety of different things to do that light exposure food timing exercise hydration caffeine yeah actually if you can learn to master this you you kind of become a master of your physiology because you understand how to manipulate it right yeah i mean i think that this is really it gives us the foundation i think to live our values with you know joy and energy and I think that's kind of at a fundamental level what we're all after.

24:39Hope you enjoyed that bite-sized clip. Do spread the love by sharing this episode with your friends and family and if you want more, why not go back and listen to the original full conversation with my guest. If you enjoyed this episode, I think you will really enjoy my bite-sized Friday email. It's called the Friday Five and each week I share things that I do not share on social media. It contains five short doses of positivity, articles or books that I'm reading, quotes that I'm thinking about, exciting research I've come across and so much more. I really think you're going to love it. The goal is for it to be a small, yet powerful dose of feel good to get you ready for the weekend.

25:21You can sign up for it free of charge at drchatterjee.com forward slash Friday Five. I hope you have a wonderful weekend. Make sure you have pressed subscribe and I'll be back next week with my long form conversation on Wednesday and the latest episode of Bite Science next Friday.