[music] I'm Alexander Heffner, your host on The Open Mind.

I'm delighted to welcome our guest today, Lynne Peeples.

She's author of the great new book, The Inner Clock Living in Sync with our Circadian Rhythms.

Welcome, Lynne.

Thank you so much for having me.

Of course.

Lynne, let me ask you, what inspired you to write about our circadian rhythms to begin with?

Yeah.

That story goes back to growing up in Seattle.

Sunny right now, but a good portion in the year, it's pretty gloomy, and the days get pretty short.

So I didn't really make any connections back in the day, but growing up, I felt my mood change with the seasons.

So seasonal affective disorder was certainly part of my life.

And I remember, like in high school, going to school in the dark and leaving after, you know, sports practice, basketball practice in the dark.

So those short days, that gloomy weather, I just I was always kind of dragging, you know, I never quite felt fully awake and fully primed to be in class, especially when classes started at 7:30 in the morning, which is totally biologically backwards for teenagers.

So, you know, that's kind of the backstory.

It wasn't until, several years ago when I moved back to Seattle after some time in the Midwest and East Coast, where I had an opportunity to tour the locker room of my hometown baseball team, the Seattle Mariners.

I've been a lifelong fan, and so I took advantage of this opportunity.

A lighting company had just installed LED lights for the field, but also for the locker room.

And as part of the tour, they took us into the locker room and they were showing off these lights that you could adjust in the intensity and the color and they talked about how this was supposed to help stabilize the player's rhythms, energize them before the games, and then calm them with different hues and a dimmer light after the game so they could sleep.

And I was intrigued.

I'm like, obviously I'm paying attention because this is like my, you know, my my childhood team and my heroes.

But like, what is going on here, did these circadian rhythms have any bearing or any explanation for what I've been feeling my whole life?

And then, you know, could these tools be helpful for me?

That's what sort of led me down the path and down many rabbit holes.

And I will note for our viewers who don't possess your book yet, the top review on Amazon, its not always a reliable metric, but it says, this is a must read if you like to find hacks.

Then they put in parentheses new techniques to improve your life.

So expound on that without giving away the whole story.

Right there.

Yeah.

There are many throughout the book, but it really comes down to three key things, that we can all do as individuals to try to help our circadian rhythms and all the benefits that come with that, which include increased productive, improved health, improved sleep.

But the first is contrast.

So that's just getting brighter light during the day and darkness at night, trying to create that contrast that the inner clocks in our bodies evolved to look for, to try to keep ticking on time.

So light in the morning, maybe you've heard is really crucial to help reset your clocks.

Light throughout the day is super helpful.

Then at night, turning off the lights, creating that contrast.

It's dark.

It's time for bed.

The second thing is, constrict, constricting your meal times.

So this was a hack that was relatively new to me is, you know, just trying to not eat at all hours of the day, which a lot of us do.

And I did, but particularly cutting off incoming calories, you know, two, three hours before bed.

Really important.

And then finally, consistency, trying to go to bed and wake up and eat at the same hours every day of the week, which is really hard to do, but kind of within those, you know, there's little hacks you can do playing with the lights to get that contrast.

Other tools, like blue light blocking glasses that people may have heard of, timing, when to take melatonin.

I talk about that in the book and what I'm really excited about it comes in later in the book, and that is circadian medicine, where we can hack when we take drugs to improve their efficacy and potentially reduce their side effects.

So it's really kind of an emerging area of this science that I think really has potential to make a lot of difference for us.

So those are your top hacks.

In practice, though, when we hear about circadian rhythms vis-à-vis sleep, what is the scientific overview that you would give a viewer watching this about sort of the birth of this science and the evolution of thinking about circadian rhythms.

Yeah.

So, I mean sleep is obviously kind of been ahead of circadian rhythms in the popular discourse.

The science of circadian rhythms goes back centuries, but it's been a trickle.

There were, you know, scientists who observed that plants appear to follow the sun.

But they would, you know, do experiments like putting a plant in a cupboard where it couldn't see the sun and it was still moving, across day and night.

So I was like, ah ha, maybe there's something going on within this plant that's keeping time.

And then it wasn't for, you know, many decades or a century later that scientists started following up on that and looking at other animals and doing some, experiments on themselves, kind of thinking about like, could humans have this too?

But it was really controversial.

And it wasn't until about 20 years ago that scientists really kind of found the smoking gun.

They discovered that we have a third photoreceptor in our eyes, does nothing to do with vision.

That takes the information from the light.

So the wavelengths and the intensity of that light, and it sends this information to, a master clock in the brain, which, decodes that message and it tells the time of day.

So this is happening again, separate from our visual system.

And it was when they found that those third photoreceptors, that it really all came together.

And scientists finally agreed, okay, there is this, inherent circadian clock network in the body that is that is keeping time.

And that's really launched between the technology, that basic understanding of the science and as that builds, that's filled in a lot of holes and also pointed to a lot of potential translation of this science to help our health and well-being.

Is that connected to REM?

R-E-M sleep?

Sleep is a huge part, is driven by our circadian rhythms.

But there's another system, the sleep homeostat, which I discuss in the book.

And these two systems work independently but in coordination with each other.

So we throughout the day, after we wake up, we build up this sleep pressure.

At the same time, our circadian rhythms are under way that dictates basically every aspect of our physiology, including our sleep.

So we've got this rhythm going on, and we also have this build up of sleep pressure, which is why, like in the afternoon, you might feel like this dip in energy and feel like you want to take a nap, but then you get kind of a boost of energy later and then, you know, closer to bedtime, you get sleepy again as melatonin starts to rise.

So our rhythms are driving all these like hormonal fluctuations and such.

But it's really, when those kind of both combine at the right time.

Ideally, if our rhythms are in sync, then it's easier to fall asleep at night and REM sleep.

I don't go into a lot of detail on that, but, we're going to maximize our REM generally speaking, if our circadian rhythms are in sync and we go to bed at the right time for our inner clocks, then things will be lined up in time to get quality sleep.

So I want to tell you something about my own sleep patterns.

Uh huh.

And maybe you relate to it in the book.

Or maybe family members have relayed this to you after writing the book, but I feel as though.

I spent so much of my youth going on 18, basically going to bed at ungodly hours.

That might have been 12, one, two, three.

Probably the mean of which is probably two, maybe, -maybe 1:30, that -Okay.

I've worked my adulthood.

The next 18 years essentially just in a baffled state.

That is probably not heeding the circadian cycles, that would, best benefit me.

Now, tell me if this is just armchair, analysis, or is if I'm onto something.

So it sounds like you're suggesting you're a night owl.

-So, you're saying... -I had been, right.

Okay, so you had been, but now you're forcing yourself up earlier.

Right, I feel as though I'm not in sync with my cycle that I, screwed up, in that my default is still going to bed at 2 or 3, and I say this, I can sleep through the night sometimes, and I know I go to bed early now, but I get up multiple times, and I attribute that to, essentially never, graduating from that routine or in sort of the permanence with which that routine has informed my later days.

Okay, a couple of things.

So, first off, our rhythms change throughout our lives.

So as a teenager, you are pretty typical that you are a night owl.

You know, I think the science is suggesting, as you hit adolescence, your circadian rhythms drift later by it could be more than two hours.

Two three hours is not abnormal.

So again, teenagers sending them to school for like a 7:30 first bell is not in their best interest.

And then as we get older, usually our rhythms shift back a little bit.

So we're more closer to being early birds.

But not all of us.

We all tick differently.

So there's a whole spectrum.

I mean, I guess, you know, most of us know that there's early birds, night owls, there's everything in between.

-However, modern society, -Yeah.

as our schedules dictate, as we, spend, you know, 90% plus of our time indoors, often away from that contrast of light and dark that we get outdoors, eating at all hours of the day.

These things exacerbate that effect.

So before modern society and our indoor lifestyle, kind of spectrum of different so-called chronotypes, which is how your clocks are ticking, was a lot narrower.

We weren't all as different as we are now.

So I guess I'll have to say your night owl-ness or whatever, you're feeling like youre going against your clocks.

That could very much be genetically true, your biology could be dictating you to want to stay up later and sleep in later.

But you could also be exacerbating that.

Based on, I don't know what your circadian hygiene is like.

If you're getting a lot of light during the day, you know what your eating schedule is, but you can kind of tighten, you know, a little bit of that.

There's wiggle room.

What's the way to assess in your mind?

Do sort of a self-evaluation.

The most effective way to do that.

I tell people, go on vacation.

You know, it's really hard in our day to day lives to get a full sense of what our clocks want us to do, because we're waking up to alarm clocks to get to work on time or to get kids up to get to school on time.

We are, you know, I mean, everything is pretty much dictated to us time wise until maybe we were in retirement.

But if you take some days off, if you have an actual vacation, that you can just let your body do what it wants, you know, don't set an alarm, go to bed when you're actually sleepy, get up when you naturally wake up.

And then on top of that, like, pay attention throughout the day.

When does your energy peak?

When do you feel most alert?

When do you have, like a spring in your step and feel like exercising?

Those things all follow rhythms throughout the day.

So it's, you know, it's helpful to get a sense of that for maybe when your body is most ready to sleep, and try to incorporate that in your day to day life, but also thinking about, okay, I, you know, for myself, I figured out that my productivity tends to peak in the late morning.

And now I try to do most of my, you know, rigorous work or writing during those hours.

So trying to maximize, the rhythms throughout the day.

Yeah.

There's that memorable scene from Seinfeld of Kramer setting his mental clock, right?

-Have you seen that episode?

-Oh, I dont know this, no.

I'm surprised it hasn't come up in the publicity for your book.

Jerry is trying to set an alarm clock for a guest.

And anyway, Kramer says he doesn't need an alarm clock.

-He's got one right up here.

-Ah, oh yeah!

Which is to say, what is your perspective on the aura rings and all of these, technologies that have developed now to try to assess our various cycles.

Do any, accurately do so?

You know, you say go on vacation, but I really meant, like, if you wanted to be able to do an MRI, if you will, of your circadian rhythms to understand what's going on and what you want to do to maybe, improve or enhance your cycles.

Am I right that some of that technology might exist?

And if so, how do you suggest deploying it?

Yeah.

There are a lot of tools, and there's continuously more of them.

I think all, they can all be helpful.

I think, you know, none of them are perfectly accurate.

For example, on, like, tracking sleep and such.

I'm still wearing, you know, one tracker right now.

And I have, you know, over the last two plus years now, I've been kind of paying attention and collecting that data and, like, paying attention, okay, you know, tonight I went ahead and had a girls night and, you know, yeah, I snack late and had some wine, you know, how did that affect my sleep?

And sure enough, it's usually bad.

But just kind of having that data and paying attention to little tweaks I make in my day to day life, and seeing the impact of that has been pretty profound.

So I find that useful.

I mean, again, it's kind of sample size varied and looking at trends because none of these tools are probably perfectly accurate.

You know, in the REM, the minutes of REM sleep that they give me, I'm sure is not exactly precise, but to see the changes with the changes I make has been helpful.

I don't know as much about, I know that there's new abilities with these apps to do things like, yeah, look at your actual circadian rhythm.

And that has sort of evolved since I finished the book.

So I'm hoping to look more into that and see exactly what they're trying to do.

But I think, yeah, the tools all have potential to help.

And, I think kind of putting together what makes sense for any individual, could provide them some help.

Towards the end of the book, you talk about, medicinal approaches to circadian patterns.

When we choose to do things like get a vaccine, or, you know, you've hinted at it already have certain meals.

What would you say, you know, beyond the hacks that you already elucidated here, were any of the more formative questions about when to do certain events in one's life that maybe we can look at from our perch now and say, okay, when I do that a year from now, I'm going to do it this time, or I'm going to change my cycle and do something in the late afternoon that I do in the morning now.

Yeah, I think that's.

Yeah.

As I kind of hinted, like, for myself, I figured out.

Okay, I'm gonna kind of shift up when I do a lot of my intense work, including my writing until, like, maybe early or late morning hours.

So I've kind of figured that piece out, I think, there's also, so it goes back to like, as individuals, our clocks all tick slightly differently.

But then if we kind of step back and look at averages, which, you know, a fair number of us kind of fall in the middle of the curve and that science suggests that on average, for example, we're at our peak in athletic performance in the late afternoon and early evening, which I found quite interesting.

And then, like you can think about the implications there for, I don't know, sports teams traveling across time zones.

I thought back about my, you know, local Seattle teams and playing East Coast teams that may fly in for, say, a 1 p.m. kickoff.

Their clocks are ticking at 4 p.m., Theyre at a circadian advantage.

That's not fair!

You know they're playing through that.

So I think yeah, we can think about it kind of personally.

And again, paying attention to when our, when our bodies are more primed to do certain things at certain times of day.

I think the science, you know, again, back to the food piece.

It's like not only constricting the hours that we eat and then focusing on cutting it off at the end of the day, but also putting more of our meals earlier in the day, because now we know that our, you know, insulin levels, our metabolism is most primed to handle those incoming calories like late morning or early afternoon, for example.

So that's hugely, I think, helpful to know, just trying to, you know, be kind to your body and and throw those insults at it when it can handle them.

And you hinted at more of the medicinal piece.

And I think there's so much potential going forward for further cool hacks that we can do to not only adjust our clocks.

There's like pills in the works that we could take potentially in the future, where our clocks could be shifted by multiple hours.

With just taking a pill, I mean, think about the implications there for jet lag or for a patient coming into the hospital where if we know that where your circadian rhythms are impact how a procedure or surgery or medications is going affect you, we could shift your clocks to match up so we could optimize that medical treatment.

And then also again yeah like timing of timing of these procedures and medicines in hospitals.

So let's close where you started, about the Mariners.

I can't say that I was a Mariners fan, but I was always impressed with Ken Griffey Jr. And found the Mariners to be an exciting team.

And, you know, Safeco, when it opened, was glorious.

And I haven't seen the latest, but, you know, it's -whether it was, glorious.

-Its still glorious.

I don't think it's name Safeco anymore, but whatever.

-Maybe it is, but -T-Mobile, yeah.

what was any of the learnings you had from the professional athletes?

Because, you know, we think that we're managing when we take one red eye, you know, in the course of a month or a year or maybe every five years, but they're at this level of athleticism.

And maybe it's just that they have the physical capacity to withstand the shifts in their circadian rhythm.

But, tell us anything more about, the experience talking to these athletes.

Yeah.

I think, sports are just really waking up to the implications of circadian rhythms.

I spoke with some quote unquote chrono coaches, which is a thing now.

So teams or individual athletes will hire these circadian experts to help them navigate.

Yeah, dealing with this jet lag as well as trying to sync up the time, their inner clock time, with the time of a competition.

So I spoke with Olympic athletes who were using so not only blue light blockers at night to cut down those blue wavelengths that could affect their sleep and their rhythms.

But also there's glasses now, speaking of hacks that will shine specifically blue light into your eyes to really enhance and wake up your circadian rhythm and shift again your inner clocks with that light.

So there, yeah, were Olympic athletes the last couple of games wearing these glasses to both like energize them before a race and also to shift their schedule or shift their inner clocks so they could be, they could overcome jet lag faster.

So I think there's yeah, these hacks, these tools are being put to use by athletes because they realize, you know, the tiniest advantage can go a long way, I mean the difference between, you know, being on a podium and not in Olympic Games, for example, can be fractions of a second.

So any little thing helps.

And circadian rhythm hacking, so to speak, could be that thing that pushes them over the end.

You write here, "More research is needed to objectively measure things like productivity, accidents, sick days, and health outcomes.

But that data, too, is beginning to come in."

How were you thinking about this from a public policy perspective of, how we can manage our lives more efficiently and fruitfully?

Understanding the science and having employers, and colleagues and family members all respect this science in how we relate to each other.

Yeah.

There's a lot of possibilities here.

So again, there's those things we can do as individuals.

But for a lot of change to happen, we really need the public policy, social change to happen.

So from a workplace perspective, I think if employees can understand that to get the most out of their workers, they can respect their workers inner clocks.

So that means, you know, A: letting them get sleep.

And if they happen to be if their clocks are maybe shifted later, perhaps not forcing them into the office at a very, very early hour, because they're not going to have, good rest.

And then also considering again, when during the day their employers are peaking in their productivity.

So I spoke with some scientists, in Europe who are implementing some of those for a lot of workplaces.

And they're doing things like, you know, flexing the work schedule so some people could come in earlier or later according to their own chronotypes, scheduling meetings, adjust in the middle of the day.

So everybody's overlapping at that time and can make that meeting.

And then maybe during that individual's productivity peak, they have like little signals they'll put up on their office or out their window so that nobody will bug them.

So nobody will stop into the office and disrupt their, focused time.

So, you know, little things like that, that could be a win win for both the employer and the employee.

And then, you know, you think about like schools again, delaying school start times, how that too could be a huge boon for students performance and health and mental health, helping them sleep and then also be more productive.

I mean, I could keep going, there's a lot of public policy implications that I talk about in the book.

Yeah.

No, please.

Anything that you think like the new Congress -ought to consider.

-Yeah.

Is this because, you know, school opening times is often going to be a locally drawn decision.

If you can point to data that shows that starting at, 9:12 rather than 7:12 for sixth, seventh and eighth graders is going to be better, then you're going to be more effective in persuading.

Right, yeah, and there's some researchers who were really focused in on this, including one at Brown University, Mary Carskadon has been.

Yeah, she can show a lot of data that I mean, when you force a student to get up early with an alarm, you're cutting off, in particular, their REM sleep, -because that happens at the end -Yeah.

of the night.

And that REM sleep is critical to like, you know, put that learning into the brain and save it for future use.

And it's important for helping their mental health and their, I don't know, everything from like car accident risks to suicide risk.

These things will go down with more REM sleep.

So yeah, I think the data is stacking up there and there is some momentum.

There is definitely and it is, like you said, local.

But that's starting to spread and some optimism that will continue.

I think another piece that I feel, pretty passionate about, that I think it's been overlooked is the idea of equity here.

I mean, we talk about food deserts in urban areas, but there's small but growing, group of advocates that are trying to raise awareness for daylight deserts as well as darkness deserts.

And so there's certain populations, often the same, that are, you know, withstanding a whole lot of challenges in their day to day lives.

But there's people who are living in spaces like basement apartments, you know, first floor apartments that are not getting a lot of daylight into their home.

And these are the same people that are most likely to be working in spaces that also don't have a lot of daylight.

So I think, you know, warehouses, back of house spaces, perhaps even working the night shift, you know, really messing with their rhythms, and then they come home at night and, you know, especially in urban centers, they're like facing an onslaught of street lights and headlights.

And I walk through social housing complexes in New York and London, where, I mean, there's these just massively bright, bright lights that are supposed to lessen crime, right, that are just blasting into residents windows.

-So the contrast in their day is -Well, you have some excellent prescriptions from the individual to the community.

Lynne, I want to thank you for writing this and for your insight today.

Oh, well, thank you so much.

It's been a pleasure.

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