September 24, 2025 • 28 mins
Science journalist Lynne Peeples did something extraordinary: She spent 10 days in a nuclear bunker exposed only to dim red light but no blue or other visible wavelength of light. She also rid the space of all clocks or other time-indicating devices and even avoided having any human contact. What she learned opened up numerous questions on how to best manage our day-to-day light exposure, wavelengths, and the implications they have on the quality of sleep, our moods, even various aspects of health and performance. After these sorts of unique experiences, along with discussions on circadian rhythms with numerous scientists working on this topic, Lynne comes to some unique conclusions.
Lynne is the author of the book “The Inner Clock: Living in Sync with Our Circadian Rhythms” in which she explores the role of purposeful management of your circadian rhythm, your inner clock, for management of energy, focus, and mood. Here, Lynne and I talk about her novel insights, along with practical advice on how to better manage your light exposure and circadian rhythm.
Lynne's book, The Inner Clock on Amazon:https://www.amazon.com/Inner-Clock-Living-Circadian-Rhythms/dp/0593538900/ref=tmm_hrd_swatch_0
Lynne's YouTube channel: https://www.youtube.com/hashtag/lynnepeeples?app=desktop
YouTube channel: https://www.youtube.com/@WilliamDavisMD
Blog: WilliamDavisMD.com
Membership website for two-way Zoom group meetings: InnerCircle.DrDavisInfiniteHealth.com
Books:
Super Gut: The 4-Week Plan to Reprogram Your Microbiome, Restore Health, and Lose Weight
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Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
William Davis, MD (00:07):
Science journalist Lynne Peoples did
something extraordinary.
She spent 10 days in a nuclearbunker, exposed only to dim red
light, but no blue or othervisible wavelength of light.
She also rid the space of allclocks or other time indicating
devices and even avoided havingany human contact.
(00:29):
What she learned opened upnumerous questions on how to
best manage our day-to-day lightexposure wavelengths and the
implications they have on thequality of sleep, our moods,
even various aspects of healthand performance.
After these sorts of uniqueexperiences, along with
discussions on circadian rhythmswith numerous scientists
(00:52):
working on this topic, lynncomes to some unique conclusions
.
Lynne is author of the book theInner Clock Living in Sync with
Our Circadian Rhythms, where sheexplores the role of purposeful
management of your circadianrhythm, your inner clock, for
management of energy, focus andmood.
(01:13):
Here, Lynne and I talk abouther novel insights, along with
practical advice on how tobetter manage your light
exposure and circadian rhythm.
Welcome, Lynne, thanks forjoining me.
I know you came.
I heard about you throughMartha Carlin and she has some
terrific ideas about yourspecial insights into circadian
(01:36):
rhythm and related type topics.
How'd you get involved in thisin the first place?
Lynne Peeples (01:41):
Well, I, you know , I think the roots of it really
go back to growing up inSeattle.
So I grew up in this placewhere the winters were very long
and very dark.
I, like a lot of us, was at ahigh school that started at 7.30
in the morning, which for weeksof the year meant going to
(02:01):
school in the dark, and I kindof yeah, I always had this sense
that, well, I didn't sleepsuper well, and then I had this
like ebb and flow throughout theyear in my mood and in my
energy and just felt kind of outof whack.
And then it wasn't until Imoved away from Seattle and went
to college in Minnesota, whereit was in the wintertime, it was
(02:23):
very cold but also very bright,and I just remember starting to
feel better.
And then it was moving back toSeattle, which was about 12
years ago now.
I had an opportunity to tour theMariners ballpark Then it was
called Safeco Field, marinersbig ballpark, then it was called
(02:47):
Safeco Field, but they had justinstalled circadian lighting in
the locker room and I had noidea what that was about.
But it was also an opportunityto go to my favorite ballpark,
where my home team played, andtour around.
So I went in there, learnedabout this lighting that they
had installed, that they wouldbrighten and enhance in the blue
wavelengths before the baseballgames and then dim and warm the
(03:09):
hues of the lights after thegames.
So it was supposed to energizethe players before the games,
calm them down after, help themsleep.
Know what was this circadianthing about, and could just the
idea behind this help explainsome of my, you know, lifelong
struggles with energy and sleep?
(03:30):
And then, I mean, thingsexploded.
I just started connecting a lotof dots, talking to hundreds of
scientists about how we havedisconnected ourselves from the
natural cycles and everythingthat is doing to our bodies.
William Davis, MD (03:48):
So you subscribe to this notion that
early morning blue is essentialfor alertness, concentration et
cetera.
Lynne Peeples (03:55):
Yeah, and for just setting our clocks to the
natural cycles, so right, it'slike the kind of direct impact
of that light on our energylevels and everything, and then
plus setting us up for successthroughout that day and the next
.
William Davis, MD (04:10):
Absolutely, it's just one part of the
equation though how are youmanaging blue later in the day?
Lynne Peeples (04:17):
Yeah, so my day I really do, yeah, as you said,
ascribe to trying to get thatfirst light of the day, whether
that's trying to get outside,which is the best, or being
close to a window as you can see, at least right now I have a
big picture window right by mydesk, so I'm super fortunate
there and then also kind offilling in where daylight can't
(04:40):
reach with some of the modernlights that do have some ability
to enhance and have more bluecolor.
And then at the end of the day Ido the opposite I cut the
lights in my apartment and ifI'm over at a friend's house or
out and about, sometimes I'mobnoxious and I do wear some
blue light blocking glasses.
(05:01):
But it's really about, yeah,brightening the day and
darkening the night.
And it's amazing, I haven'tthought about it, but we don't.
We evolved with these fancyrods in our eyes that really can
adapt to darkness, and so I Ican get by with just these
electric candles that I havearound my apartment, which just
(05:24):
give off this warm glow, right,and that's, you know, it's
enough to see.
So, yeah, there's many toolsout there.
William Davis, MD (05:32):
Have you had a chance to incorporate red
infrared into your schedule?
Lynne Peeples (05:37):
You know.
So that's sort of outside thescope of my book.
But I do have some interest inthat and have been sort of
researching it on the side anddo play around with red light.
I don't know where the date,I'm sure you know more than I
but it seems like there's somegrowing data that it can help
heal and do various things forour bodies.
So I've been using it on somejoints that have been less than
(06:00):
healthy to see if that helps.
But generally speaking, I meanthe red that I used in the scope
of circadian rhythms in my bookis just for the point that it
doesn't affect our circadianrhythms like blue light does.
So when I did an experimentwhere I stayed 10 nights in a
nuclear bunker, for example, Ihad the whole bunker set to just
(06:25):
a dim red light because I wasexperimenting on what would
happen to my body.
So I wanted to eliminate anysense of daylight.
So I use red light.
William Davis, MD (06:34):
Tell us more about that.
Why is that?
Lynne Peeples (06:36):
Yeah.
So I was seeking out a spacewhere I could kind of go to the
extreme and cut myself off fromany cues that my body could use
to tell day from night.
Because that's our modern worldand that is really the problem.
That's how we're disconnectingourselves in these rhythms that
(06:57):
our bodies evolved to do theright things at the right time,
without access to the cues,primarily light and dark, while
the planet spins.
So without that, yeah, we'redisrupting our circadian rhythms
.
So I was trying to cut myselfoff from daylight as well, as
you know, obviously, any clocksthat are going to tell me the
(07:19):
time, or any other human beingsor creatures that also have
rhythm that could give me anyclues.
And the best thing I found wasvia Airbnb.
This man in Arkansas had boughta former Cold War era nuclear
missile silo from the government, had gutted it and refurbished
(07:43):
it into a fancy Airbnb, and so Igot in touch with him and
stayed in this.
It was the command controlcenter for this nuclear missile.
I stayed down there for 10 daysand he helped me.
Just, you know, cover everyclock that was visible and, you
(08:03):
know, set these LED lights to bered and dim, just enough to see
, but not enough to mess up myinner clocks.
What happened?
And oh, and I also bigimportant point I decked my
whole body out with variousdevices that were measuring my
rhythms.
So I had little buttons tapedto me that were measuring my
(08:25):
temperature.
I was wearing a glucose monitor.
I obviously was, as you mightguess, wearing garments and
various devices measuring sleepand heart rate.
And then, at the end of theexperiment, so I was uploading
all this data and then I workedwith scientists to look at these
rhythms, to see what actuallyhappened over those 10 days.
(08:48):
And yeah, sure enough, my bodyfell out of sync with the sun,
it drifted, and, what's more,that these rhythms in my body
fell out of sync with each other, and so it's much like jet lag.
So we've all probably most ofus at least, have experienced
that to some extent in our lives.
But this was essentially anextreme form of it.
(09:09):
I, you know, drifted later,which a lot of us naturally do,
because, on average, our innerclocks run a little longer than
24 hours, which is why we needto keep sync to the sun, because
it kind of keeps pulling usback to be closer to that 24
hour day.
But my heart rate rhythm and mytemperature rhythm.
These, you know, fell out ofsync with each other and that
(09:32):
translated into I didn't feel sowell, you know, my, my thinking
was slower, my coordination wasdown.
I was actually practicingjuggling in the bunker.
I tried to teach myself tojuggle all kinds of interesting
things to fill the time, but Iwas taking notes on a voice
recorder and various things andI could really see from the data
(09:55):
afterwards at about the pointthat I was feeling pretty
miserable was when the datashowed that I really fell out of
sync and it was also kind ofthe extent or the amplitude of
the rhythms in my body flattened.
So I just I really I lostrhythm.
William Davis, MD (10:15):
What became of mood?
Lynne Peeples (10:17):
Yeah, the mood followed that too.
So it's really a body and brainphenomenon.
So I a body and brainphenomenon, so I, yeah, I felt
more depressed, I felt moreanxious.
I also I struggled to sleep,like it was sort of you know.
I felt like I just kind ofwanted to nap all the time.
I really lacked, lacked thatrhythm.
(10:37):
You know that awake during theday, sleepy at night, and then
you know the the positive energywas essentially drained from me
.
William Davis, MD (10:46):
Did any of your devices give you any kind
of feedback on sleep cycles?
Lynne Peeples (10:50):
Yeah, so I was tracking my sleep cycles
Definitely lost.
I mean, if we're talking aboutthe detail, you know I could see
that I had less REM sleep, forsure, and uh, heart rate, you
know, didn't drop as much atnight as it did before the
experiment no, it's reallyinteresting it was kind of the
same like the amplitude of myrhythms, so that included, um,
(11:13):
yeah, heart rate, temperatureand sleep.
It was just, yeah, everythingkind of flat lined would you
learn um.
William Davis, MD (11:20):
Would you learn with blood sugar?
Lynne Peeples (11:22):
blood sugar.
It wasn't as like obvious, butI definitely it did fall out of
sync too with the other rhythms.
And you know it's a complicatedone because it's like you know
there's so many factors goinginto what you're putting into
your body.
But but yeah, the blood sugarspikes did get kind of a little
more extreme because, as we know, if you're not eating when your
(11:45):
body is primed to handle thoseincoming calories, it's not
going to, you know, serve you aswell.
Your insulin and everything isnot going to be ready to tackle
that.
So you know it's hard to infertoo much, but you could see some
greater spikes and again, youknow the overall rhythm was a
bit out of sync.
William Davis, MD (12:04):
And you managed to maintain a healthy
diet during the entireexperiment.
Lynne Peeples (12:08):
I did.
You know, I went down therewith a bunch of bags of Whole
Foods groceries and I mean theone kind of fun little anecdote
that came from that.
And this was, I swear, notplanned, but it was two days
before the end of the experiment, I believe.
I was running low on food.
(12:28):
It was dinner time, so I didn'tplan this perfectly Right.
But uh, I you know I used toalways like breakfast for dinner
.
So I was like, okay, I'm out oflike my main dinner foods, but
I have, I still have somepancake mix and some blueberries
.
So I made myself a blueberrypancake for dinner that night
(12:52):
and later, when I went back tothe data, it was clear that I
was actually eating thatblueberry pancake in the morning
when everybody above ground wasalso having breakfast.
So I thought that was amusing.
William Davis, MD (13:00):
Anything interesting with regards to
dream content?
Lynne Peeples (13:04):
Ooh, that's a good question.
You know, I do not rememberanything really standing out
except and I did make a note ofthis but didn't really do
anything with it I did havemoments where I'd see light,
like I'd close my eyes andthere'd be kind of these flashes
of light.
(13:25):
It was almost like my brain wasjust craving daylight.
So I would see these, yeah,almost, I mean just really vivid
, kind of bright.
William Davis, MD (13:33):
Why did you choose to use a low-level red
light the entire time?
Lynne Peeples (13:49):
Because the science shows that red light is
going to be least impactful toour circadian rhythms.
Because we have these thirdphotoreceptors that were only
recently discovered in our eyesright and those.
They act separately from ourvisual system, but they're there
.
They're constantly trying topick up cues from from light and
dark.
So they're looking for theintensity of light and they're
really keying in on bluewavelengths, because that is the
(14:10):
main kind of wavelengths thatthe sun's pumping out.
In the middle of the day it's afull spectrum, of course, but
the peak is really in the bluewavelengths.
So when you get out to the reds, that's going to be more kind
of.
You know, end of the day you'regoing to get a little more of
the red coming through, but it'sjust less likely to tell your
(14:32):
body it's daytime.
So that's what the scientistsreally kind of urge.
You know, at the end of the dayyou want those warmer hues and
then red light is least likelyto confuse your brain.
William Davis, MD (14:44):
So you do this crazy 10 day experiment?
What happened when you finished, when you left?
Lynne Peeples (14:50):
Yeah, well, first it was just, it was really wild
to step up from that bunker andsee the sun.
I was, oh my gosh, I wasblinded, so my eyes had not seen
that for a while, so I was likeI had sunglasses on and it was
cloudy, but I was still kind ofblinded by the light, literally.
And then it took some days formy body to get back in sync.
(15:15):
And again, you can compare thisto maybe traveling
internationally, because, alsoit's part of my book, I did go
to Europe for a while to do somereporting and I came back and
it was a similar, similar thingof trying to readjust right
after, you know, crossingseveral time zones.
(15:37):
So, yeah, it was probably abouta week before I really got got
my rhythms back and connectedagain.
But yeah, but it was, it was areally.
It was really fun, yeah, andit's interesting experience kind
of going, going, going throughthose rhythms with the
scientists, you know, drawingthese diagrams and graphs,
looking at how these thingsmatched up or or didn't over the
course of the time down theredid you manage or manipulate
your vitamin d at all?
(15:58):
oh, I did not.
No, I mean obviously.
Yeah, that's one component,right?
If I'm not getting any sun, I'mnot getting any natural vitamin
D.
So, yeah, maybe that was partof it.
Inherently, I was craving that,so I did spend a lot of time
outdoors when I got out.
I live by a park here inSeattle and I do like to walk
(16:19):
around green light here and Iwas doing that a little extra.
Plus, I could see color for thefirst time in weeks, cause when
you live in dim red light, youdon't see much color.
So I was really happy to bereunited with color.
William Davis, MD (16:36):
I'm glad you made that point about getting
sunlight is the best solution,Cause I do see a lot of well, I
think red light has a role, asyou know, a different kind of
role than blue, but I see peoplesaying things like I live in
Honolulu or Phoenix or Miami andI get lots of red light.
No, no, go outside, Go outside.
(16:57):
You can't do any better thansun.
Lynne Peeples (16:59):
Oh no, we evolved for this.
Yeah, we evolved for thenatural sun.
We evolved for this.
Yeah, we evolved for thenatural.
William Davis, MD (17:05):
Natural said.
So what have you learned, Lynn,that you've applied in your own
life?
Now understanding what you knowabout the circadian rhythm.
Lynne Peeples (17:22):
Yeah, so I've realized that you know, like a
lot of us, without knowing it,you know I've cut myself off
from a lot of these importantcues.
So I was talking earlier about,you know, brightening the day
and darkening the night.
So that's definitely one.
Got my blue blockers.
Oh, nice, well, actually a keyto that.
So it's and I'm sure you'reprobably aware of this, but they
do like lens makers are reallykind of pumping out these blue
light blocking coatings on a lotof prescription lenses that you
(17:44):
can buy.
But if you're wearing thoseduring the day, that's not
really necessarily helping outyour inner clocks, because we
want to really get as much bluelight as we possibly can during
the day.
At night, yes, blocking thatblue light could benefit you,
but we kind of need to maybe bewatching out for that.
It's not filtering a ton.
(18:05):
So if you're really out enoughduring the day, even if you're
wearing prescription lenses withsome blue light filter on them,
not a big deal, but just wantsomething to be aware of.
Yeah, so I'm really I'm tryingto just get outside more
Morning's critical, but reallythroughout the day, just the
most light daylight we canaccumulate, the better, and
(18:27):
there's some more and moreresearch coming out, even just
in the last few months, abouthow it really is across the
course of the day, just the morelight we can get, and then
contrast that with as dark as wecan get our nights.
Now research is finding that onaverage, we live longer.
I mean that goes hand in handwith being healthier, but really
interesting.
And then the other components,though beyond just the light and
(18:49):
dark, is thinking about really,what else are we doing or
telling our bodies?
What other signals can we giveour bodies that it's day versus
night?
And if you think about how weevolved, you know our ancestors
were not eating 24 seven.
You know they tended to eatduring the daylight hours.
You know maybe there'd be ahunt, bring back the animal or
(19:09):
they're out.
You know harvesting berriesright, they were eating during
the daylight hours.
They weren't going out in thedark.
It was risky and unsafe.
And so that's our.
Our bodies evolved to really beable to handle incoming calories
during the day and we peak inour ability to do so late
(19:31):
morning, early afternoon.
So it's sort of the opposite, orclose to the opposite, of a lot
of the Western diets out there,where we really concentrate our
calories at the end of the daywe have this big dinner and
sometimes that bleeds into likethe later evening hours and the
science suggests that stoppingany incoming calories at least
(19:51):
three hours before bed reallyserves us well and that allows
us it'll be easier to fallasleep, it helps our inner
clocks stay in sync and itimproves our metabolism less
likely to develop metabolicdisorders, if we can really
consolidate the hours that weeat, keep it earlier in the day
and then try not to have thatmidnight snack or a sip of wine
(20:15):
or anything else that's going toconfuse our inner clocks.
So I think it's yeah, it's thekind of the three C's is what
I've talked about.
So it's that contrast of lightand dark.
It's constricting I've talkedabout.
So it's that contrast of lightand dark.
It's constricting yourmealtimes.
And then the third C I like totalk about is consistency, and
this is becoming more and moreimportant.
The science is reallyunderscoring that going to bed,
(20:38):
getting up, eating, exercising,doing these things at the same
time every day helps our bodiespredict and prepare for those
activities and that's reallygoing to help our health and
happiness and productivity andperformance all those things.
William Davis, MD (20:54):
How have these insights led to any change
in sleep habits?
Lynne Peeples (21:00):
Yeah, I really am patting myself on the back.
I feel like I've become muchbetter about being consistent.
You know, like I on the back, Ifeel like I've become much
better about being consistent.
I break the rules.
Hopefully we enjoy social livesand doing things that might
mean compromising here and there.
I now try to go to bed between10.30 and 11 every night and
(21:26):
tend to wake up and get uparound 7, 7.30 every day and
that shifts a little bitdepending on the time of year.
You know, here in Seattle thereis a huge swing in when the sun
rises across the course of theyear, so it's easier to get up
early in the summer.
But generally speaking I feellike I am, you know, a lot more
(21:47):
consistent with that and Ireally have tried to embrace
this the meal timing bit.
So if I'm at least not out withfriends, that I'm really trying
to embrace this, the mealtiming bit If I'm at least not
out with friends, then I'mreally trying to cut off.
I stop eating anything afterabout seven.
No snacks.
Try not to have that glass ofwine later in the evening that I
used to have, I found because Iwas wearing Fitbits or other
(22:10):
trackers.
While they may not be superaccurate bits or other trackers.
While they may not be superaccurate, they do help.
You see trends and I could tellthat my sleep was way higher
quality if I would be consistentand if I didn't confuse my
clocks by eating too late.
William Davis, MD (22:27):
And it helps, doesn't it, to remind everybody
, this is not a phenomenonunique to humans.
Lynne Peeples (22:32):
No, right, no, all life, just about all life
that we've found, evolved withinner clocks and for similar
reasons, right Again, if having.
I don't know if I've mentionedthis yet, but I mean we have
trillions of clocks in ourbodies, like every cell in your
body has a clock, and we evolvedwith these so that they would,
(22:53):
you know, coordinate with theenvironment and coordinate with
each other to prime our bodiesto do the right things at the
right time, so we can, you knowagain, handle those incoming
calories or defend ourselvesfrom any pathogens that are
trying to break through, rightLike, if we have our defenses up
all the time, we're going torun out of energy.
So we have these ebbs and flowsin all our body systems, and
(23:16):
that's the same for plants, it'sthe same for animals, you know,
down to microorganisms.
We're finding that inner clocksreally kind of pave the way for
survival.
William Davis, MD (23:27):
Speaking of inner clock, could you tell us
about your book?
Lynne Peeples (23:30):
Yeah, so yeah, my book.
It came out the end ofSeptember of 2024.
It's called the Inner Clock andit really does.
It tells the story.
You know, as we've hinted atI've put myself in the story a
bit with some personalexperiments the basic biology of
(23:51):
the circadian system that wenow are really grow, have grown
to appreciate all the more forhow it impacts our overall,
overall health, how it impactsour productivity, our
performance, whether you knowyou're thinking about your
workplace and you know when youmight be primed to do the best
work or have a more productiveconversation with a colleague.
(24:15):
So if you're an athlete, youknow how can you optimize your
performance.
All these things really do leanon the health of our circadian
system and timing our days.
So I talk about, yeah, theunderlying science there.
What modern life has you know,unfortunately, done to keep us
(24:35):
from being optimal in thoseregards?
And then what we can do.
And there's just really, asI've hinted, some simple things
that we can do and there are afew more, maybe more surprising
tools that we can enlist toimprove our health and then even
kind of hack our rhythms to goeven further.
Some really cool researchcoming out of NASA and DARPA and
(24:58):
elsewhere, from independentscientific labs that are looking
at.
Now that we understand thisscience better and now that we
have this technology emerging,how can we really leverage this
to further help human health,and then also think of it
society-wide?
What can we do about daylightsaving time and school start
(25:20):
times and these other factorsthat are affecting us that we
may not have been thinking abouttoo closely before?
So what's?
William Davis, MD (25:27):
your opinion On the whole, the wholesale
conversion from incandescent toblue LED, blue dominant LED, all
times of day.
Has that been a benefit,Putting aside the energy saving
issue, the human issue, has itbeen a beneficial thing or a
harmful thing?
Lynne Peeples (25:49):
So I think the science coming in on the whole
suggests that could be a moreharmful thing.
So incandescence we weregetting some wavelengths that we
are no longer getting.
Some interesting researchcoming out now about violet
light, for example, that is justcompletely absent from indoor
environments, both because ourwindow coatings are filtering a
(26:10):
lot of it out, plus our lightsare not providing that, and
we're finding some healthrepercussions of blocking violet
light, for example.
But yeah, and at night, if wehad incandescent lights on,
there was less of that bluelight confusing our inner clocks
During the day.
You know, maybe LEDs have aslight edge over incandescent,
(26:32):
but again, maybe because thelack of violet light, you know
it's.
There's a lot of variables atplay here.
But the interesting thing andthe unfortunate thing is that
LEDs you know it's good thatthey're energy efficient, right,
there's a reason that we'vemade this transition and that is
great for for the climate, forour environmental future.
But because they last so long ifpeople have invested in this
(26:53):
the climate for ourenvironmental future but because
they last so long, if peoplehave invested in the cheap,
standard LEDs, it's probablygoing to be a long time until
they consider swapping those outand we know now that their
technology is advanced and wecan get LEDs that can be way
healthier.
We can have LEDs now that aretunable, where we can brighten
(27:15):
them, dim them, change thewavelengths to get the
appropriate wavelength for theappropriate time of the day.
So you can buy one light bulb,have it bright and blue during
the day and then dim it to awarmer hue at night.
But most companies they'regoing to buy the cheap one,
right, and then that's going tobe installed for the next 20
(27:36):
years because ideally, I guessenergy-wise, it doesn't go out.
So we've kind of got ourselvesin this predicament now and you
think about that indoor lightingas well as outdoor lighting.
There's a lot of pushback nowabout streetlights.
They're a little glaring, youmight say, and that's strong in
the blues.
William Davis, MD (27:56):
It's an evolving conversation, isn't it?
Lynne Peeples (27:58):
It is Same thing with headlights too.
I know I personally struggledriving now with the bright LED
headlights that seem to be veryubiquitous out there.
William Davis, MD (28:10):
Now, if some listeners want to engage in the
Lynn Peoples conversation, wherewould they do that?
Lynne Peeples (28:16):
Yeah, you can find me at lynnpeoplescom
L-Y-N-N-E-P-E-E-P-L-E-S.
And then my book the InnerClock is available anywhere you
buy your books.
William Davis, MD (28:27):
Great Lynn.
Thank you very much for takingthe time and sharing your
insights.
Lynne Peeples (28:30):
Yeah, thanks so much for having me.
Science journalist Lynne Peoples did
something extraordinary.
She spent 10 days in a nuclearbunker, exposed only to dim red
light, but no blue or othervisible wavelength of light.
She also rid the space of allclocks or other time indicating
devices and even avoided havingany human contact.
(00:29):
What she learned opened upnumerous questions on how to
best manage our day-to-day lightexposure wavelengths and the
implications they have on thequality of sleep, our moods,
even various aspects of healthand performance.
After these sorts of uniqueexperiences, along with
discussions on circadian rhythmswith numerous scientists
(00:52):
working on this topic, lynncomes to some unique conclusions
.
Lynne is author of the book theInner Clock Living in Sync with
Our Circadian Rhythms, where sheexplores the role of purposeful
management of your circadianrhythm, your inner clock, for
management of energy, focus andmood.
(01:13):
Here, Lynne and I talk abouther novel insights, along with
practical advice on how tobetter manage your light
exposure and circadian rhythm.
Welcome, Lynne, thanks forjoining me.
I know you came.
I heard about you throughMartha Carlin and she has some
terrific ideas about yourspecial insights into circadian
(01:36):
rhythm and related type topics.
How'd you get involved in thisin the first place?
Lynne Peeples (01:41):
Well, I, you know , I think the roots of it really
go back to growing up inSeattle.
So I grew up in this placewhere the winters were very long
and very dark.
I, like a lot of us, was at ahigh school that started at 7.30
in the morning, which for weeksof the year meant going to
(02:01):
school in the dark, and I kindof yeah, I always had this sense
that, well, I didn't sleepsuper well, and then I had this
like ebb and flow throughout theyear in my mood and in my
energy and just felt kind of outof whack.
And then it wasn't until Imoved away from Seattle and went
to college in Minnesota, whereit was in the wintertime, it was
(02:23):
very cold but also very bright,and I just remember starting to
feel better.
And then it was moving back toSeattle, which was about 12
years ago now.
I had an opportunity to tour theMariners ballpark Then it was
called Safeco Field, marinersbig ballpark, then it was called
(02:47):
Safeco Field, but they had justinstalled circadian lighting in
the locker room and I had noidea what that was about.
But it was also an opportunityto go to my favorite ballpark,
where my home team played, andtour around.
So I went in there, learnedabout this lighting that they
had installed, that they wouldbrighten and enhance in the blue
wavelengths before the baseballgames and then dim and warm the
(03:09):
hues of the lights after thegames.
So it was supposed to energizethe players before the games,
calm them down after, help themsleep.
Know what was this circadianthing about, and could just the
idea behind this help explainsome of my, you know, lifelong
struggles with energy and sleep?
(03:30):
And then, I mean, thingsexploded.
I just started connecting a lotof dots, talking to hundreds of
scientists about how we havedisconnected ourselves from the
natural cycles and everythingthat is doing to our bodies.
William Davis, MD (03:48):
So you subscribe to this notion that
early morning blue is essentialfor alertness, concentration et
cetera.
Lynne Peeples (03:55):
Yeah, and for just setting our clocks to the
natural cycles, so right, it'slike the kind of direct impact
of that light on our energylevels and everything, and then
plus setting us up for successthroughout that day and the next
.
William Davis, MD (04:10):
Absolutely, it's just one part of the
equation though how are youmanaging blue later in the day?
Lynne Peeples (04:17):
Yeah, so my day I really do, yeah, as you said,
ascribe to trying to get thatfirst light of the day, whether
that's trying to get outside,which is the best, or being
close to a window as you can see, at least right now I have a
big picture window right by mydesk, so I'm super fortunate
there and then also kind offilling in where daylight can't
(04:40):
reach with some of the modernlights that do have some ability
to enhance and have more bluecolor.
And then at the end of the day Ido the opposite I cut the
lights in my apartment and ifI'm over at a friend's house or
out and about, sometimes I'mobnoxious and I do wear some
blue light blocking glasses.
(05:01):
But it's really about, yeah,brightening the day and
darkening the night.
And it's amazing, I haven'tthought about it, but we don't.
We evolved with these fancyrods in our eyes that really can
adapt to darkness, and so I Ican get by with just these
electric candles that I havearound my apartment, which just
(05:24):
give off this warm glow, right,and that's, you know, it's
enough to see.
So, yeah, there's many toolsout there.
William Davis, MD (05:32):
Have you had a chance to incorporate red
infrared into your schedule?
Lynne Peeples (05:37):
You know.
So that's sort of outside thescope of my book.
But I do have some interest inthat and have been sort of
researching it on the side anddo play around with red light.
I don't know where the date,I'm sure you know more than I
but it seems like there's somegrowing data that it can help
heal and do various things forour bodies.
So I've been using it on somejoints that have been less than
(06:00):
healthy to see if that helps.
But generally speaking, I meanthe red that I used in the scope
of circadian rhythms in my bookis just for the point that it
doesn't affect our circadianrhythms like blue light does.
So when I did an experimentwhere I stayed 10 nights in a
nuclear bunker, for example, Ihad the whole bunker set to just
(06:25):
a dim red light because I wasexperimenting on what would
happen to my body.
So I wanted to eliminate anysense of daylight.
So I use red light.
William Davis, MD (06:34):
Tell us more about that.
Why is that?
Lynne Peeples (06:36):
Yeah.
So I was seeking out a spacewhere I could kind of go to the
extreme and cut myself off fromany cues that my body could use
to tell day from night.
Because that's our modern worldand that is really the problem.
That's how we're disconnectingourselves in these rhythms that
(06:57):
our bodies evolved to do theright things at the right time,
without access to the cues,primarily light and dark, while
the planet spins.
So without that, yeah, we'redisrupting our circadian rhythms
.
So I was trying to cut myselfoff from daylight as well, as
you know, obviously, any clocksthat are going to tell me the
(07:19):
time, or any other human beingsor creatures that also have
rhythm that could give me anyclues.
And the best thing I found wasvia Airbnb.
This man in Arkansas had boughta former Cold War era nuclear
missile silo from the government, had gutted it and refurbished
(07:43):
it into a fancy Airbnb, and so Igot in touch with him and
stayed in this.
It was the command controlcenter for this nuclear missile.
I stayed down there for 10 daysand he helped me.
Just, you know, cover everyclock that was visible and, you
(08:03):
know, set these LED lights to bered and dim, just enough to see
, but not enough to mess up myinner clocks.
What happened?
And oh, and I also bigimportant point I decked my
whole body out with variousdevices that were measuring my
rhythms.
So I had little buttons tapedto me that were measuring my
(08:25):
temperature.
I was wearing a glucose monitor.
I obviously was, as you mightguess, wearing garments and
various devices measuring sleepand heart rate.
And then, at the end of theexperiment, so I was uploading
all this data and then I workedwith scientists to look at these
rhythms, to see what actuallyhappened over those 10 days.
(08:48):
And yeah, sure enough, my bodyfell out of sync with the sun,
it drifted, and, what's more,that these rhythms in my body
fell out of sync with each other, and so it's much like jet lag.
So we've all probably most ofus at least, have experienced
that to some extent in our lives.
But this was essentially anextreme form of it.
(09:09):
I, you know, drifted later,which a lot of us naturally do,
because, on average, our innerclocks run a little longer than
24 hours, which is why we needto keep sync to the sun, because
it kind of keeps pulling usback to be closer to that 24
hour day.
But my heart rate rhythm and mytemperature rhythm.
These, you know, fell out ofsync with each other and that
(09:32):
translated into I didn't feel sowell, you know, my, my thinking
was slower, my coordination wasdown.
I was actually practicingjuggling in the bunker.
I tried to teach myself tojuggle all kinds of interesting
things to fill the time, but Iwas taking notes on a voice
recorder and various things andI could really see from the data
(09:55):
afterwards at about the pointthat I was feeling pretty
miserable was when the datashowed that I really fell out of
sync and it was also kind ofthe extent or the amplitude of
the rhythms in my body flattened.
So I just I really I lostrhythm.
William Davis, MD (10:15):
What became of mood?
Lynne Peeples (10:17):
Yeah, the mood followed that too.
So it's really a body and brainphenomenon.
So I a body and brainphenomenon, so I, yeah, I felt
more depressed, I felt moreanxious.
I also I struggled to sleep,like it was sort of you know.
I felt like I just kind ofwanted to nap all the time.
I really lacked, lacked thatrhythm.
(10:37):
You know that awake during theday, sleepy at night, and then
you know the the positive energywas essentially drained from me
.
William Davis, MD (10:46):
Did any of your devices give you any kind
of feedback on sleep cycles?
Lynne Peeples (10:50):
Yeah, so I was tracking my sleep cycles
Definitely lost.
I mean, if we're talking aboutthe detail, you know I could see
that I had less REM sleep, forsure, and uh, heart rate, you
know, didn't drop as much atnight as it did before the
experiment no, it's reallyinteresting it was kind of the
same like the amplitude of myrhythms, so that included, um,
(11:13):
yeah, heart rate, temperatureand sleep.
It was just, yeah, everythingkind of flat lined would you
learn um.
William Davis, MD (11:20):
Would you learn with blood sugar?
Lynne Peeples (11:22):
blood sugar.
It wasn't as like obvious, butI definitely it did fall out of
sync too with the other rhythms.
And you know it's a complicatedone because it's like you know
there's so many factors goinginto what you're putting into
your body.
But but yeah, the blood sugarspikes did get kind of a little
more extreme because, as we know, if you're not eating when your
(11:45):
body is primed to handle thoseincoming calories, it's not
going to, you know, serve you aswell.
Your insulin and everything isnot going to be ready to tackle
that.
So you know it's hard to infertoo much, but you could see some
greater spikes and again, youknow the overall rhythm was a
bit out of sync.
William Davis, MD (12:04):
And you managed to maintain a healthy
diet during the entireexperiment.
Lynne Peeples (12:08):
I did.
You know, I went down therewith a bunch of bags of Whole
Foods groceries and I mean theone kind of fun little anecdote
that came from that.
And this was, I swear, notplanned, but it was two days
before the end of the experiment, I believe.
I was running low on food.
(12:28):
It was dinner time, so I didn'tplan this perfectly Right.
But uh, I you know I used toalways like breakfast for dinner
.
So I was like, okay, I'm out oflike my main dinner foods, but
I have, I still have somepancake mix and some blueberries
.
So I made myself a blueberrypancake for dinner that night
(12:52):
and later, when I went back tothe data, it was clear that I
was actually eating thatblueberry pancake in the morning
when everybody above ground wasalso having breakfast.
So I thought that was amusing.
William Davis, MD (13:00):
Anything interesting with regards to
dream content?
Lynne Peeples (13:04):
Ooh, that's a good question.
You know, I do not rememberanything really standing out
except and I did make a note ofthis but didn't really do
anything with it I did havemoments where I'd see light,
like I'd close my eyes andthere'd be kind of these flashes
of light.
(13:25):
It was almost like my brain wasjust craving daylight.
So I would see these, yeah,almost, I mean just really vivid
, kind of bright.
William Davis, MD (13:33):
Why did you choose to use a low-level red
light the entire time?
Lynne Peeples (13:49):
Because the science shows that red light is
going to be least impactful toour circadian rhythms.
Because we have these thirdphotoreceptors that were only
recently discovered in our eyesright and those.
They act separately from ourvisual system, but they're there
.
They're constantly trying topick up cues from from light and
dark.
So they're looking for theintensity of light and they're
really keying in on bluewavelengths, because that is the
(14:10):
main kind of wavelengths thatthe sun's pumping out.
In the middle of the day it's afull spectrum, of course, but
the peak is really in the bluewavelengths.
So when you get out to the reds, that's going to be more kind
of.
You know, end of the day you'regoing to get a little more of
the red coming through, but it'sjust less likely to tell your
(14:32):
body it's daytime.
So that's what the scientistsreally kind of urge.
You know, at the end of the dayyou want those warmer hues and
then red light is least likelyto confuse your brain.
William Davis, MD (14:44):
So you do this crazy 10 day experiment?
What happened when you finished, when you left?
Lynne Peeples (14:50):
Yeah, well, first it was just, it was really wild
to step up from that bunker andsee the sun.
I was, oh my gosh, I wasblinded, so my eyes had not seen
that for a while, so I was likeI had sunglasses on and it was
cloudy, but I was still kind ofblinded by the light, literally.
And then it took some days formy body to get back in sync.
(15:15):
And again, you can compare thisto maybe traveling
internationally, because, alsoit's part of my book, I did go
to Europe for a while to do somereporting and I came back and
it was a similar, similar thingof trying to readjust right
after, you know, crossingseveral time zones.
(15:37):
So, yeah, it was probably abouta week before I really got got
my rhythms back and connectedagain.
But yeah, but it was, it was areally.
It was really fun, yeah, andit's interesting experience kind
of going, going, going throughthose rhythms with the
scientists, you know, drawingthese diagrams and graphs,
looking at how these thingsmatched up or or didn't over the
course of the time down theredid you manage or manipulate
your vitamin d at all?
(15:58):
oh, I did not.
No, I mean obviously.
Yeah, that's one component,right?
If I'm not getting any sun, I'mnot getting any natural vitamin
D.
So, yeah, maybe that was partof it.
Inherently, I was craving that,so I did spend a lot of time
outdoors when I got out.
I live by a park here inSeattle and I do like to walk
(16:19):
around green light here and Iwas doing that a little extra.
Plus, I could see color for thefirst time in weeks, cause when
you live in dim red light, youdon't see much color.
So I was really happy to bereunited with color.
William Davis, MD (16:36):
I'm glad you made that point about getting
sunlight is the best solution,Cause I do see a lot of well, I
think red light has a role, asyou know, a different kind of
role than blue, but I see peoplesaying things like I live in
Honolulu or Phoenix or Miami andI get lots of red light.
No, no, go outside, Go outside.
(16:57):
You can't do any better thansun.
Lynne Peeples (16:59):
Oh no, we evolved for this.
Yeah, we evolved for thenatural sun.
We evolved for this.
Yeah, we evolved for thenatural.
William Davis, MD (17:05):
Natural said.
So what have you learned, Lynn,that you've applied in your own
life?
Now understanding what you knowabout the circadian rhythm.
Lynne Peeples (17:22):
Yeah, so I've realized that you know, like a
lot of us, without knowing it,you know I've cut myself off
from a lot of these importantcues.
So I was talking earlier about,you know, brightening the day
and darkening the night.
So that's definitely one.
Got my blue blockers.
Oh, nice, well, actually a keyto that.
So it's and I'm sure you'reprobably aware of this, but they
do like lens makers are reallykind of pumping out these blue
light blocking coatings on a lotof prescription lenses that you
(17:44):
can buy.
But if you're wearing thoseduring the day, that's not
really necessarily helping outyour inner clocks, because we
want to really get as much bluelight as we possibly can during
the day.
At night, yes, blocking thatblue light could benefit you,
but we kind of need to maybe bewatching out for that.
It's not filtering a ton.
(18:05):
So if you're really out enoughduring the day, even if you're
wearing prescription lenses withsome blue light filter on them,
not a big deal, but just wantsomething to be aware of.
Yeah, so I'm really I'm tryingto just get outside more
Morning's critical, but reallythroughout the day, just the
most light daylight we canaccumulate, the better, and
(18:27):
there's some more and moreresearch coming out, even just
in the last few months, abouthow it really is across the
course of the day, just the morelight we can get, and then
contrast that with as dark as wecan get our nights.
Now research is finding that onaverage, we live longer.
I mean that goes hand in handwith being healthier, but really
interesting.
And then the other components,though beyond just the light and
(18:49):
dark, is thinking about really,what else are we doing or
telling our bodies?
What other signals can we giveour bodies that it's day versus
night?
And if you think about how weevolved, you know our ancestors
were not eating 24 seven.
You know they tended to eatduring the daylight hours.
You know maybe there'd be ahunt, bring back the animal or
(19:09):
they're out.
You know harvesting berriesright, they were eating during
the daylight hours.
They weren't going out in thedark.
It was risky and unsafe.
And so that's our.
Our bodies evolved to really beable to handle incoming calories
during the day and we peak inour ability to do so late
(19:31):
morning, early afternoon.
So it's sort of the opposite, orclose to the opposite, of a lot
of the Western diets out there,where we really concentrate our
calories at the end of the daywe have this big dinner and
sometimes that bleeds into likethe later evening hours and the
science suggests that stoppingany incoming calories at least
(19:51):
three hours before bed reallyserves us well and that allows
us it'll be easier to fallasleep, it helps our inner
clocks stay in sync and itimproves our metabolism less
likely to develop metabolicdisorders, if we can really
consolidate the hours that weeat, keep it earlier in the day
and then try not to have thatmidnight snack or a sip of wine
(20:15):
or anything else that's going toconfuse our inner clocks.
So I think it's yeah, it's thekind of the three C's is what
I've talked about.
So it's that contrast of lightand dark.
It's constricting I've talkedabout.
So it's that contrast of lightand dark.
It's constricting yourmealtimes.
And then the third C I like totalk about is consistency, and
this is becoming more and moreimportant.
The science is reallyunderscoring that going to bed,
(20:38):
getting up, eating, exercising,doing these things at the same
time every day helps our bodiespredict and prepare for those
activities and that's reallygoing to help our health and
happiness and productivity andperformance all those things.
William Davis, MD (20:54):
How have these insights led to any change
in sleep habits?
Lynne Peeples (21:00):
Yeah, I really am patting myself on the back.
I feel like I've become muchbetter about being consistent.
You know, like I on the back, Ifeel like I've become much
better about being consistent.
I break the rules.
Hopefully we enjoy social livesand doing things that might
mean compromising here and there.
I now try to go to bed between10.30 and 11 every night and
(21:26):
tend to wake up and get uparound 7, 7.30 every day and
that shifts a little bitdepending on the time of year.
You know, here in Seattle thereis a huge swing in when the sun
rises across the course of theyear, so it's easier to get up
early in the summer.
But generally speaking I feellike I am, you know, a lot more
(21:47):
consistent with that and Ireally have tried to embrace
this the meal timing bit.
So if I'm at least not out withfriends, that I'm really trying
to embrace this, the mealtiming bit If I'm at least not
out with friends, then I'mreally trying to cut off.
I stop eating anything afterabout seven.
No snacks.
Try not to have that glass ofwine later in the evening that I
used to have, I found because Iwas wearing Fitbits or other
(22:10):
trackers.
While they may not be superaccurate bits or other trackers.
While they may not be superaccurate, they do help.
You see trends and I could tellthat my sleep was way higher
quality if I would be consistentand if I didn't confuse my
clocks by eating too late.
William Davis, MD (22:27):
And it helps, doesn't it, to remind everybody
, this is not a phenomenonunique to humans.
Lynne Peeples (22:32):
No, right, no, all life, just about all life
that we've found, evolved withinner clocks and for similar
reasons, right Again, if having.
I don't know if I've mentionedthis yet, but I mean we have
trillions of clocks in ourbodies, like every cell in your
body has a clock, and we evolvedwith these so that they would,
(22:53):
you know, coordinate with theenvironment and coordinate with
each other to prime our bodiesto do the right things at the
right time, so we can, you knowagain, handle those incoming
calories or defend ourselvesfrom any pathogens that are
trying to break through, rightLike, if we have our defenses up
all the time, we're going torun out of energy.
So we have these ebbs and flowsin all our body systems, and
(23:16):
that's the same for plants, it'sthe same for animals, you know,
down to microorganisms.
We're finding that inner clocksreally kind of pave the way for
survival.
William Davis, MD (23:27):
Speaking of inner clock, could you tell us
about your book?
Lynne Peeples (23:30):
Yeah, so yeah, my book.
It came out the end ofSeptember of 2024.
It's called the Inner Clock andit really does.
It tells the story.
You know, as we've hinted atI've put myself in the story a
bit with some personalexperiments the basic biology of
(23:51):
the circadian system that wenow are really grow, have grown
to appreciate all the more forhow it impacts our overall,
overall health, how it impactsour productivity, our
performance, whether you knowyou're thinking about your
workplace and you know when youmight be primed to do the best
work or have a more productiveconversation with a colleague.
(24:15):
So if you're an athlete, youknow how can you optimize your
performance.
All these things really do leanon the health of our circadian
system and timing our days.
So I talk about, yeah, theunderlying science there.
What modern life has you know,unfortunately, done to keep us
(24:35):
from being optimal in thoseregards?
And then what we can do.
And there's just really, asI've hinted, some simple things
that we can do and there are afew more, maybe more surprising
tools that we can enlist toimprove our health and then even
kind of hack our rhythms to goeven further.
Some really cool researchcoming out of NASA and DARPA and
(24:58):
elsewhere, from independentscientific labs that are looking
at.
Now that we understand thisscience better and now that we
have this technology emerging,how can we really leverage this
to further help human health,and then also think of it
society-wide?
What can we do about daylightsaving time and school start
(25:20):
times and these other factorsthat are affecting us that we
may not have been thinking abouttoo closely before?
So what's?
William Davis, MD (25:27):
your opinion On the whole, the wholesale
conversion from incandescent toblue LED, blue dominant LED, all
times of day.
Has that been a benefit,Putting aside the energy saving
issue, the human issue, has itbeen a beneficial thing or a
harmful thing?
Lynne Peeples (25:49):
So I think the science coming in on the whole
suggests that could be a moreharmful thing.
So incandescence we weregetting some wavelengths that we
are no longer getting.
Some interesting researchcoming out now about violet
light, for example, that is justcompletely absent from indoor
environments, both because ourwindow coatings are filtering a
(26:10):
lot of it out, plus our lightsare not providing that, and
we're finding some healthrepercussions of blocking violet
light, for example.
But yeah, and at night, if wehad incandescent lights on,
there was less of that bluelight confusing our inner clocks
During the day.
You know, maybe LEDs have aslight edge over incandescent,
(26:32):
but again, maybe because thelack of violet light, you know
it's.
There's a lot of variables atplay here.
But the interesting thing andthe unfortunate thing is that
LEDs you know it's good thatthey're energy efficient, right,
there's a reason that we'vemade this transition and that is
great for for the climate, forour environmental future.
But because they last so long ifpeople have invested in this
(26:53):
the climate for ourenvironmental future but because
they last so long, if peoplehave invested in the cheap,
standard LEDs, it's probablygoing to be a long time until
they consider swapping those outand we know now that their
technology is advanced and wecan get LEDs that can be way
healthier.
We can have LEDs now that aretunable, where we can brighten
(27:15):
them, dim them, change thewavelengths to get the
appropriate wavelength for theappropriate time of the day.
So you can buy one light bulb,have it bright and blue during
the day and then dim it to awarmer hue at night.
But most companies they'regoing to buy the cheap one,
right, and then that's going tobe installed for the next 20
(27:36):
years because ideally, I guessenergy-wise, it doesn't go out.
So we've kind of got ourselvesin this predicament now and you
think about that indoor lightingas well as outdoor lighting.
There's a lot of pushback nowabout streetlights.
They're a little glaring, youmight say, and that's strong in
the blues.
William Davis, MD (27:56):
It's an evolving conversation, isn't it?
Lynne Peeples (27:58):
It is Same thing with headlights too.
I know I personally struggledriving now with the bright LED
headlights that seem to be veryubiquitous out there.
William Davis, MD (28:10):
Now, if some listeners want to engage in the
Lynn Peoples conversation, wherewould they do that?
Lynne Peeples (28:16):
Yeah, you can find me at lynnpeoplescom
L-Y-N-N-E-P-E-E-P-L-E-S.
And then my book the InnerClock is available anywhere you
buy your books.
William Davis, MD (28:27):
Great Lynn.
Thank you very much for takingthe time and sharing your
insights.
Lynne Peeples (28:30):
Yeah, thanks so much for having me.
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CrimeLess: Hillbilly Heist
It’s 1996 in rural North Carolina, and an oddball crew makes history when they pull off America’s third largest cash heist. But it’s all downhill from there. Join host Johnny Knoxville as he unspools a wild and woolly tale about a group of regular ‘ol folks who risked it all for a chance at a better life. CrimeLess: Hillbilly Heist answers the question: what would you do with 17.3 million dollars? The answer includes diamond rings, mansions, velvet Elvis paintings, plus a run for the border, murder-for-hire-plots, and FBI busts.
Dateline NBC
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