Pod Insights Feel Better, Live More with Dr Rangan Chatterjee BITESIZE | Do This Every Morning to Boost Your Energy, Improve Your Sleep and Optimise Your Health | Dr Kristen Holmes #538 About this episode In our hyper-connected modern world, where we have access to artificial light around the clock, we’ve drifted far from our body’s natural rhythms. But what if reconnecting with these internal clocks could be the key to unlocking better health, more energy, and even a longer life?
Feel Better Live More Bitesize is my weekly podcast for your mind, body, and heart. Each week I’ll be featuring inspirational stories and practical tips from some of my former guests.
Today's clip is from episode 479 of the podcast with scientist and researcher Dr Kristen Holmes.
Kristen is Global Head of Human Performance and Principal Scientist at WHOOP and a Science Advisor to Levels Health and Arena Labs.
In this clip, we explore the world of circadian biology and she shares how reconnecting with our body’s natural rhythms could help us reclaim our energy and optimise our health.
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Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
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1:20 Rangan Chatterjee? See all details at drinkag1.com/livemore. Welcome to Feel Better, Live More Bite Size, your weekly dose of positivity and optimism to get you ready for the weekend. Today's clip is from episode 479 of the podcast with scientist and researcher Dr. Kristin Holmes. In our modern world, where we have access to artificial light around the clock, we've drifted far away from our bodies' natural rhythms. And in this clip, we explore the world of circadian biology.
2:01 Rangan Chatterjee? And Kristin shares how reconnecting with these natural rhythms could help us reclaim our energy and optimise our health.
2:12 Speaker 01 Circadian rhythms and circadian alignments is the foundation of your house. And when that is not firing on all cylinders, anything we attempt to layer on top of that is really just layering inefficiency on top of inefficiency. So, you know, any nutrition protocols that we're trying to deploy or any, you know, exercise, like in order to really capitalize on these other things that we're doing, the timing of when we're viewing light, when we're restricting light, when we are eating, when we are sleeping, when we're waking up and when we're active, help and train our circadian rhythm. So the timing of those things is absolutely central to our overall health and longevity.
2:56 Rangan Chatterjee? Yeah, no, I love the way you put that. I've been a medical doctor now for 23 years and I'm always focusing on, for me, what I call these four pillars of health, food, movement, sleep and relaxation. You know, one thing I've realized over the past, I would say at least a decade, is that if you haven't got the basic foundational pillars of health dialed in as well as you can, you simply don't know how many of your symptoms are just a consequence of that. Right? So as doctors, we often will treat your symptoms and say you have this condition and you may
3:36 Rangan Chatterjee? do, but sometimes that's just a natural consequence of the fact that you are living in some sort of circadian misalignment. So of course your mood is low, of course your brain function isn't where you want it to be, of course you're putting on weight, et cetera, et cetera.
3:53 Speaker 01 Yeah.
3:54 Rangan Chatterjee? Like if I can dial that in with my patients, you often find that a lot of the downstream symptoms just kind of go away as a consequence.
4:02 Speaker 01 Yeah, I think that's beautifully said, of course. And it's not that we don't go wrong, but I think people, we think about sleep, for example, right? Sleep is, doesn't have a circadian rhythm, but it's an output of the circadian clock, right? So it's our daytime behaviors that dictate, you know, our ability to fall asleep and stay asleep and get that beautiful restorative night's sleep, right? We might talk about our sleep hygiene, which is very important, right? But, but unless our circadian rhythms are aligned, sleep is going to 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. And as
4:45 Speaker 01 a result, we're creating, you know, 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.
5:00 Rangan Chatterjee? I'd love you to explain what is a circadian rhythm? 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. Of 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?
5:26 Speaker 01 Yeah, so circadian rhythms, very simply, are the physical, mental, and behavioral processes that are happening over a 24-hour cycle. And there's lots and lots of evidence in the literature that the consequences of desynchronized circadian rhythms, that is basically bypassing our natural internal preferences, right? Which we want to try to match our natural internal preferences with the light-dark cycle. That's like the most prominent cue to entrain our circadian rhythms and to create this circadian alignment. So, for example, when we are viewing light at a phase of the natural light-dark cycle,
6:11 Speaker 01 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
6:30 Speaker 01 Are become disorganized or don't quite know what to do. And this creates misalignment, right? And that creates stress on our system. So, and that stress, of course, manifests in very real ways, right? In terms of suppressing our immune system. And 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
7:15 Speaker 01 and our autonomic nervous system, our sympathetic branch of our nervous system is chronically activated. This, this leads to disease and aging. Now, there are other behaviors that help and train our circadian rhythm. So 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.
7:50 Rangan Chatterjee? Are you saying that everyone has an internal rhythm that that has presumably been set in some way based upon their lifestyle and the way they're living? But 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.
8:14 Speaker 01 Yeah.
8:15 Rangan Chatterjee? With shift work, as it can be more challenging and we'll talk about that for sure.
8:19 Speaker 01 Yeah, that's exactly right. And, you know, in all of the research that I've done over the course of the last four years for my, my thesis, the one behavior that bubbles up and is predictive of physiological and psychological functioning is sleep-wake timing. The more stable it is, the better levels of, the higher levels of psychological functioning, okay, the more positive psychological functioning folks have, and the stronger the physiological markers. So we see relationships between when we do these circadian behaviors, they impact our sleep-wake time. And I think, I think where we go a little wrong is I think we believe that there is enormous variability, talking about the general healthy population
9:04 Speaker 01 in terms of our internal preferences. And we know this from, you know, a lot of the literature and a lot of the research that's done on hunter-gatherers, they're all gonna wake a little bit up after sunrise and they're gonna fall asleep a little bit after sunset, right? And indeed, when you put, you know, folks like us on a mountain with no electricity, we're all gonna fall asleep within a half an hour of each other. You know, there's other evidence too, when we look at 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 11:00 PM and 4:00 AM, your dopamine system,
9:45 Speaker 01 motivation, reward, just doesn't work as well as it would have if you didn't view light between 11:00 PM and 4:00 AM. 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 11:00 PM and 4:00 AM, 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 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's time to be awake at times when, again, they're not programmed to be awake. They'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
10:29 Speaker 01 something that we need to protect this timeframe.
10:33 Rangan Chatterjee? Yeah.
10:34 Speaker 01 This is a time when we are not supposed to be active and awake.
10:38 Rangan Chatterjee? Yeah, what you said about we're not as varied as we might think. I'm so happy to hear you say that. You 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, right?
11:22 Rangan Chatterjee? 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?
11:50 Speaker 01 It really does. And the evidence is just so darn clear to me. You know, um, this notion that we have these really, you know, varied chronotypes that span five hours. When I interpret the literature, that's just not, that's not what I see, right? I see preferences, you know? And I think we've, we've created this notion of chronotype out of convenience, you know, really. Because it's just, let's focus off the hook, you know? It's, you know, I'm the night owl. I'm going to stay up, but I'm going to watch Netflix until 1 a.m. You know, we're really making choices, right? And, and we just have to own that choice. But we have to recognize that it is having a deleterious effect on our health, well being and our longevity, right?
12:34 Speaker 01 Mental, physical, emotional.
12:36 Rangan Chatterjee? What you said about dopamine was really interesting. You mentioned that if we are regularly up, looking at lights between 11 p.m. and 4 a.m.
12:46 Rangan Chatterjee? Then our dopaminergic system doesn't work as well the following day. Now, 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. We know that our circadian rhythm is not exactly 24 hours, right? It's slightly beyond that. And then we are setting it every day based on light and dark.
13:31 Speaker 01 That's right.
13:32 Rangan Chatterjee? So the fact that we can change and respond to jet lag and time zones means that we can change it and our environmental inputs ultimately are what dictate it, right? So that, I think it's empowering because it goes, okay, what choices can I make to harmonize my circadian rhythm in the context of my life as much as I can?
13:55 Speaker 01 Yeah, I've seen in my own experience, you know, as a coach, I was, you know, very much a night owl, like, 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 I've personally have been able to shift my circadian rhythm to an optimal kind of zone. And I have seen, I can see now that I had just literally adapted to a lower level of functioning. Like, I didn't even know what I was leaving on the table. You know, I thought I was being so productive and I was, by all intensive purposes, very successful. When I look back on like my health, I was a mess.
14:38 Speaker 01 It has, it's completely transformed my life, aligning my circadian rhythms.
14:42 Rangan Chatterjee? 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's simply not true.
14:51 Speaker 01 You can change.
14:52 Rangan Chatterjee? You can change any time you want. Yes, for some people, it's harder than others. 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. But I imagine also, there's been a feed forward cycle whereby it was, it was hard initially, but then you start to feel the benefits.
15:17 Speaker 01 It's just a way of life now.
15:18 Rangan Chatterjee? Yeah. And then you want to continue that way. That's how I feel.
15:21 Speaker 01 Oh, yeah.
15:21 Rangan Chatterjee? I love living in good circadian harmony. I just feel great. You have concluded, along with the research, that a regular sleep-wake time is one of the top line behaviors we should all be striving for.
15:36 Speaker 01 I will go on a limb and say that I, I think it is the most important behavior, if we're talking about wanting to really optimize our health and longevity. And I try to keep my variability, you know, around 30 minutes. I think when we, when we have a stable sleep-wake time and we're getting, sufficient sleep matters, right? We need to spend enough time in bed, right? There's no question. And I think, you know, that sweet spot for folks is somewhere, you know, between seven and eight hours for like adults. And, and I will say that when folks start to stabilize their sleep-wake time, they end up with less light sleep, less awake sleep, right? Because their sleep becomes more efficient.
16:18 Speaker 01 And when people are trying to, to kind of incorporate a more stable sleep-wake time, the most important thing is to wake up at the same time every day and view light, even if it means potentially having a bit of a shorter sleep. That that same wake up time is absolutely critical for setting your circadian rhythm, right? And dropping melatonin at the time that you need to, right, to fall asleep and stay asleep. When we talk about the the coaching piece of circadian alignment, that's where you start. You wake up if I 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.
17:00 Speaker 01 You want to look up at the sky for at least five, you know, to 10 minutes and then go about your day. Right? That's going to help set your circadian rhythm. People spend 97% of their adult lives indoors.
17:14 Rangan Chatterjee? Yeah. So we're missing the the the number one input, which is lights.
17:19 Speaker 01 Yeah, natural light.
17:20 Rangan Chatterjee? Okay, so this is super fascinating. Okay, so it can be challenging for people in different jobs and different points in their life. But if possible, you're saying try and have the same bedtime and the same wake time. If you're slightly off on your bedtime, try and keep the wake time consistent. If you do need to shift it a little bit day to day, try not to more than 30 minutes or so. Is that kind of the essence of the sleep wake recommendations?
17:51 Speaker 01 And then we know that the bare minimum that folks should be spending outdoor is 67 minutes. If we are interested in mental health. So just the natural light in general has such an impact on on our skin health, on vitamin D, our our mental health, our mood, our alertness. So important, right? That's what we know in the that's kind of the what's been defined in the literature as being like the minimum effective dose for humans.
18:18 Rangan Chatterjee? Yeah, I mean, that's that's fascinating. And I think that makes complete sense. I mean, we've we've evolved outdoors. We've never spent this long inside. 67 minutes, though, to some people will be like, wow.
18:29 Speaker 01 It's an eternity. I did not spend 67 minutes outside yesterday, but I'm acutely aware. And I know today, fortunately, it's a it's a holiday and I'm gonna I'll be outside all the rest of the day. You know, I'm gonna kind of make up for it. And I think that that, you know, it doesn't. It's not a perfect science, but that's kind of in my head how I think about it. And I just try to, on average, across a month, schedule my time so I can hit these minimum thresholds.
18:55 Rangan Chatterjee? Yeah.
18:56 Speaker 01 And that's really how I'm operating. Yeah.
19:00 Rangan Chatterjee? Now, I must deal with night shift workers.
19:02 Speaker 01 I know.
19:03 Rangan Chatterjee? And I really don't want people leaving this feeling
19:05 Speaker 01 Yeah.
19:06 Rangan Chatterjee? worried and scared, right?
19:07 Speaker 01 I know, I know.
19:08 Rangan Chatterjee? So, okay, you did a series of beautiful Instagram videos, which I would direct people to if they want to know your views on this, right?
19:15 Speaker 01 Yes.
19:15 Rangan Chatterjee? One was if you're on a series of night shifts. So, I don't know, when I was a junior doctor, we would do seven nights in a row, for example.
19:23 Speaker 01 Right, right.
19:24 Rangan Chatterjee? You had some advice on how to stay on a night pattern. It's all there in those Instagram posts. I wonder if you could share some of your top line recommendations there, please?
19:34 Speaker 01 Yes, and again, this is the caveat is you need to be able to do this, all of these things I'm talking about as safely as possible, right? I think sleeping as close to the end of your shift is, from what I've seen, what I've heard, and in the data that we have on frontline healthcare clinicians, that seems to be the best protocol to get in the most hours of sleep during the night and have the most restorative sleep. People who delay their sleep end up with much shorter sleep and more fragmented sleep. Try to minimize light in the lead up to bed, so sunglasses, hats. Again, as safely as you can, because that light to the eye, again, is really going to wake up the system. And then you want to try to sleep, you know, for seven hours minimum.
20:18 Speaker 01 So, you know, like a consolidated sleep. And then when you wake up, work out, have a meal, be active, you know, catch up with the family before you go on to your shift.
20:29 Rangan Chatterjee? Yeah.
20:30 Speaker 01 Right, yeah.
20:31 Rangan Chatterjee? 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. 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?
20:55 Speaker 01 Yeah, there's lots of subjective questions, you know, that we, we should be asking ourselves. What are my energy levels? Do I feel alert when I want to feel alert? Do I feel sleepy when I want to feel sleepy? Am I attending to things that I care about? Am I able to control and direct my thoughts, right? Like, these are questions that all humans should be asking of themselves, right? The answer to those questions is a direct comment on likely how we're managing our physiology. It gives us the foundation, I think, to live our values with, you know?
21:26 Speaker 01 Joy and energy.
21:28 Rangan Chatterjee? Okay.
21:29 Speaker 01 And I think that's kind of at a fundamental level, what we're all after.
21:32 Rangan Chatterjee? Hope you enjoyed that bite sized clip. Hope you have a wonderful weekend and I'll be back next week with my long form conversation on Wednesday and the latest episode of Bite Science next Friday.
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