The World’s No.1 Sleep Expert: The 6 Sleep Hacks You NEED! Matthew Walker
3252 segments
when you're struggling with sleep in the
middle of the night and you're wide
awake in the last hour before bed try
this experiment
I'm I'm sold Matthew Walker
neuroscientist and best-selling author
and one of the world's leading
researchers in sleep science it's gonna
blow your mind there's a global sleep
loss epidemic shaped by this thing
called the modern world what Society
wants is that you're either producing or
you're consuming in fact the CEO of
Netflix his statement was that we are to
commit war against sleep we have this
mentality in business less sleep equals
more productivity that is just not true
insufficient sleep costs most Nations
about 411 billion dollars
your rates of obesity cardiovascular
disease mental health conditions all of
these things escalate if that wasn't bad
enough oh my God if you're not getting
sufficient sleep then 60 of all of the
weight that you lose will come from lean
muscle mass and not fat not the muscle
how would you redesign Society to help
us to sleep better so first I would
feels like caffeine is a miracle drive
with no apparent cost was I wrong or was
I right wrong caffeine will hurt your
sleep in three ways most people are not
aware of so if you have a cup of coffee
at midday what happens is that
before we get into this episode just
wanted to say thank you first and
foremost for being part of this
community
um the team here at the diver CEO is now
almost 30 people and that's literally
because you watch and you subscribe and
you um leave comments and you like the
videos that this show has been able to
grow and it's the greatest honor of my
life to sit here with these incredible
people and just selfishly ask them
questions that I'm pondering over or
worrying about in my life but this is
just the beginning for the day of this
year we've got big big plans to scale
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let's get on with it
[Music]
I have spent the longest time trying to
sit down with you on this podcast I'm
very very happy to spend some time with
you today
and that is because your your work is
now world renowned
um and it's a very very important work
but
as is the case with a few of the recent
episodes in this podcast I wanted to
start by asking you
in your view
what is it you do and why is it so
important in your mind that you do it
well firstly thank you so much for
having me here and having this
conversation it's an incredible
privilege to sit with you
um why do I do what I do and why do I
think it's important
um sleep I would argue is the single
most effective thing that you can do to
reset your brain and body health
and I don't say that flippantly it's not
as though I'm dismissing exercise or
Diet those two things are absolutely
critical but if I were to take you the
individual and deprive you of exercise
for a day deprive you of food for a day
deprived you of water for a day or
deprive you of sleep for a day 24 hours
and I were to map your brain and body
impairments it's not even a competition
that one night of lost sleep relative to
those other things it dwarfs the only
thing I lose out against is oxygen if I
deprive you oxygen you're going to Puff
out of existence a little bit quicker
than you will with a lack of sleep so
sleep to me I think is the elixir of
life it is your life support system and
as best we can tell I would argue it's
Mother Nature's Best effort yet at
immortality
and so in that regard that's why I when
I look across all of the studies and all
of the data it's so compelling to me and
part of the reason I think it's I've
desperately tried and I haven't done a
good job but I've tried to offer some
public mission of reuniting Humanity
with the sleep that it's so bereft of is
because it does appear that there is a
global sleep loss epidemic if you look
at the numbers people are struggling so
desperately with their sleep so we have
all of this knowledge this incredible
knowledge of sleep and how important it
is and it's a perfect storm colliding
with this great sleep depression in
modern society and for that reason I
just felt as though what can I do to try
to help offer this voice and this
science and I am but a scientist and I
stand on the shoulders of all of my
colleagues and all of these Giants in
the field I'm just a researcher so
that's a little bit about I guess who I
am but more about why I do it and why I
think it's important if I were to try
and Define your sort of unless I hate
doing this because it requires the
application of some kind of narrow label
if I was to try and Define what your
title is in your own words what would
that be so I'm just a professor of
Neuroscience of brain science at the
University of California Berkeley
um I am I am not a medical doctor just
FYI for all of the things that we will
talk about in this conversation so I'm
just a PhD
just a PhD yeah you know that's um
incredibly humble of you but but I would
assert that you're without a shadow of a
doubt the leading
author scientist commentator voice as it
relates to the topic of sleep
and my my question from that is where
did that begin like where did that start
in your life in the Journey of your life
when did sleep become the thing
it occurred to me or happened to me I
should say when I was doing my PhD I was
studying people with dementia and we
were trying to understand what type of
different dementia that they had very
early on in the course of their disease
and we were looking at patterns of
brainwave activity so I was placing
electrodes all over the head and I was
measuring them and I was trying to
differentially diagnose them very early
on and I was getting no good data
whatsoever it's miserable nothing was
was Landing
and one day I went home at the weekend
and sort of with all of my printed
journals and I go to the my doctor's
residence and have this sort of igloo of
journals around me that I would sit and
read at the weekend
um and I was which probably tells you
everything about my social life at the
weekend if that's what I was doing but
um so I was reading these journals and
it occurred to me that some of these
dementias were eating away at the Sleep
Centers in the brain and others would
leave them untouched and at that moment
I realized I'm measuring my patience at
the wrong time I'm measuring them when
they're awake should be measuring them
when they're asleep
started doing that got amazing results
and at that point I wanted to ask the
question well I wonder if the Sleep
problems are not simply a symptom of the
dementia
I wonder if it's a potential cause of
the dementia
and at that point I started to think
well so then what is this thing called
sleep
and what I learned is that some of the
greatest Minds in the past 100 years had
tried to answer a very simple question
why do we sleep
and you know 30 years ago in fact the
crass answer was that we sleep to cure
sleepiness
which tells you nothing about you know
it's like saying I eat to cure hunger
well no you that's not the right answer
now 30 years later we've had to upend
the question and we now have to ask is
there any physiological system in your
body is there any operation of your mind
that isn't wonderfully enhanced when you
get sleep or demonstrably impaired when
you don't get enough and the answer
seems to be to be nother so my journey
into the science of sleep really was an
accident but at that moment in time when
I started reading about sleep I utterly
fell in love with the topic
and it is a love affair that has lasted
me over 20 years
I think it is the most beguiling Topic
in all of science I'm biased of course
and I will never study anything
different I know that now I'll study it
to the end of my career and until the
end of my life
wow
I've never heard anybody say to me on
this podcast that they would study
the same topic for the rest of their
life and you're a young man that's a
you've got a long way to go actually the
amount you've been sleeping it's very
kind of you to say yeah I I wish I'm
moving into the foothills of middle age
rapidly but no I I'm so fortunate in
what I do
um to have found it or for it to have
found me you know if I won all of the
money in the world tomorrow
I would genuinely genuinely not do
anything different
um I I am so fortunate well I probably
start trying to fly like business class
or first class that would be nice but
other than that
um I would do nothing different and I
I'm very mindful of that because that
sounds very privileged and I know a lot
of people
endure what they do for a living rather
than enjoy what they do for a living
and I know how lucky I am so I don't
mean to be dismissive of of people in
that regard I just know how much I love
what I do you you asked a question now
which is
um you you posed a question which many
people have tried to answer you gave the
the answer from 30 years ago about you
know why do we sleep
um and it dawned on me as you said that
that I've never asked myself that
question
I've never even pondered the thought of
why I sleep I mean I know what happens
when I sleep but do I know why my body
can't just find another way why can't my
body stay awake for the 24 hours I know
some animals they sleep half their brain
and then the other half kind of it
doesn't happen whatever why why why do
we sleep
it's a puzzling question because when
you think about it from an evolutionary
perspective it makes no sense whatsoever
sleep is utterly
idiotic because when you're sleeping
firstly you're not finding a mate you're
not reproducing you're not foraging for
food you're not caring for your young
and worst of all You're vulnerable to
predation now on any one of those
grounds but especially all of them as a
collective sleep should have been
strongly selected against during the
course of evolution
but from best we can tell sleep evolved
with life itself on this planet and it
has fought its way through heroically
every step along the evolutionary path
and what that has told us is that sleep
must be essential at the most basic of
biological levels and now we understand
that mother nature didn't make a
spectacular blunder with this thing
called sleep sleep for example will
restock the Weaponry in your immune
Arsenal and it will make you a more
immune sensitive individual so your more
immune robust when you wake up
we also know that it regulates your
blood sugar levels it controls your
appetite hormones it also regulates your
sex hormones testosterone estrogen sleep
upstairs within the brain will fixate
memories and help you learn and remember
sleep will de-escalate anxiety it will
reduce your emotional difficulties and
traumas sleep will actually cleanse away
the Alzheimer's toxic proteins that
build up in the brain you know the list
is endless these are all of the reasons
that we need to sleep
but why can't I just do what those
animals do where they half their brain
falls asleep after the brain stays awake
is that at all linked to the fact that
we we live in tribes so we are
essentially although we're you know
there might be 10 people in the tribe
where
all 10 of the tribe so we can rest at
different times and kind of cover each
other's backs or
gosh yeah so actually there are two
nested very insightful questions there
the first is this notion of what you're
describing which is what we call uni
hemispheric sleep which is just a fancy
way of saying you can sleep with one
half of your brain and the other half is
wide awake now there are only a few
species that can do this
um for example aquatic mammals dolphins
are a great example we can place
actually electrodes on their heads and
you can see that one half of their brain
will be fast asleep it will be in deep
deep non-rem sleep the other half of the
brain will be frenetic wide awake and in
part for them the reason is because they
need to maintain aquatic Mobility you
know they need to keep surfacing for ER
otherwise you know that's not going to
be a good outcome we also know that uh
birds or even many avian species will
have uni hemispheric sleep and you can
actually see this there's some great
YouTube videos online where they will
film one half of the sort of the side of
the The Bird's face and the eye is
closed and what it means is that the
other half of the brain because the
brain is actually the left half controls
the right side the right side controls
the left side so that left side is now
fast asleep which is the right eye
closed and then you kind of pan around
and all of a sudden the other eye is
wide awake and it's clearly looking
about now this is obviously not for
aquatic surfacing to gain air this is
for a different reason what happens is
that in a flock a bunch of birds will
all land on a branch
now all of the folks in the middle they
get to sleep with both halves of their
brain they can sleep with both halves or
just one half all of the folks in the
middle they get to sleep with both
halves the unfortunate girl or guy who
sort of lands at the end to the far end
they will actually sleep with one half
of their brain so one half of the flock
the entire flock has one eye 180 degrees
of sort of half panoramic view
out the other bird on the other end will
have the other half of the brain asleep
with the other eye awake giving the
other 180 degree view of protection
vision and therefore the entire tribe
has a 360 degree assessment now you
would think in furnace that once those
guys or girls at the end have done their
Duty they get to move into the middle
and they get to sleep with both halves
no that's not what happens what they
will do after a while is that they will
stand up they will turn around 180
degrees sit back down and switch the
other sides of the brain
so to to just be clear the complexity of
wiring and architecture that has to
happen for one half of the brain to be
deep in sleep and the other half to be
wide awake is astronomically hot I mean
it's incredibly difficult to create that
wiring what that tells me is that if
sleep was dispensable if it was
negotiable then mother nature would have
just found a different way for us to get
all of these brain and body benefits and
not gone to all of the evolutionary
trouble of figuring out this fancy
wiring for half brain sleep in other
words you just can't get away from sleep
you have to sleep but your second
question I think is is even more
fascinating which is us as a tribe
because we are a tribe species
now there is something else that we call
your chronotype are you a morning type
evening type or somewhere in between
and by the way you don't get to decide
it's not your choice you know this
notion of these go-getter type A's who
say everyone has to be awake at five in
the morning you know you go to the gym
you blast out a workout for an hour and
you're at the desk by 6am
um you have no choice if you're an
evening type you're an evening type it's
hard-coded we know that right now
there's at least 22 different genes that
dictate what you are morning type
evening type or somewhere in between and
it's about third third split across the
population why is it a split why are we
nicely spread out across our chronotypes
for exactly the reason you described
because when we're in a tribe if we all
sleep at the same time we're all
vulnerable for eight hours
but if you were to insert some genetic
variability into when people have a
desire to sleep you've got the morning
types who maybe go to bed at 9 00 pm and
are waking up let's say at 5 00 am and
then you've got all of the extreme
evening types who are going to bed at
2AM and waking up at maybe 11 or midday
so that way the everyone gets their
eight hours of sleep but the entire
tribe the nucleus of this group of homo
sapiens themselves is only vulnerable
for maybe just two or three hours so
it's a clever solution that Mother
Nature has come up with to say everyone
gets there eight hours but as a species
you're only going to be vulnerable for
two to three hours max when everyone at
least as a collective is sleeping
absolute genius I used to think it was a
load of nonsense that this Chrono type
thing um it was actually on this podcast
where I learned about its existence and
then I went on YouTube to learn more and
your video came up if you're explaining
it because I thought I was pondered by
my partner goes to bed super early wakes
up super early I go to bed late wake up
late
um
I'm gonna ask you this question actually
because because I've wondered this in
that situation where I'm sleeping in bed
with a partner that has a different
chronotype yeah
it can have an impact on my sleep right
because of the way that our sleep cycles
work and the REM sleep in the stage one
deep sleep etc etc if she's waking up
when I'm pulling into REM sleep I she's
waking up at 5am but at 5am because I've
gone to bed later my REM sleep has just
begun that has quite a significant
impact on me right
if she is waking you up yeah she's
waiting if she wakes me up then it's
non-trivial and likewise if you're
waking her up as you're getting into bed
on the front end of sleep
so it's very difficult one of the things
that couples will cite if they break up
firstly is usually about a third of them
will cite sleep difficulties or sleep
issues really as a as a cause of their
their breakup or at least as a
contributing factor to that breakup
one-third yeah that it's one of at least
one of the factors when you go it then
in and when you double click to say okay
then what it is about this sleep kind of
tension between the two of you one of
those things is a mismatch in chronotype
and you can see this when you know
people I think this you know on dating
profiles now someone was telling me
people will even say like I'm a morning
type or I'm an evening type as if you're
stating up front this is part of my
identity and just FYI be forewarned
because maybe it's been an issue for
them in the past
this is why I often speak about the
notion of what's called a sleep divorce
to prevent a real one now it's not for
everyone um a sleep divorce is where you
sleep in separate locations
and when we've surveyed people
um both uh use it in the from the Sleep
Council in the United Kingdom and also
in the National sleep Foundation here in
America the data is about the same one
in four people will say that they sleep
in different locations with their
partner so almost a quarter of people in
relationships will sleep in different
locations we think it's potentially an
underestimate because if you survey
people anonymously
then a third of them will report waking
up at least in a different location the
next morning
and part of the reason that it's a taboo
is because people think well if I'm if
we're not sleeping together then we're
not sleeping together the exact opposite
is true that when a couple is sleeping
well
we know that the sex hormones are
improved testosterone men estrogen and
uh at least an icing hormone in women we
also know that your
um desire to be intimate with your
partner is increased what we found is
that for an hour of extra sleep if a
woman gets an hour of extra sleep her
libido desire to be intimate with her
partner increases by 14 percent
now to give you some context the FDA
drugs for improving or increasing libido
in women drugs such as violisi here
clinical drugs they will increase it by
about 24 and that's a pharmacological
agent but here just the added
non-pharmacological benefit of one hour
of extra sleep will get you more than 50
percent of the way there
so I want to just remove that notion of
the stigma
of that if you're not sleeping together
you're not sleep it's usually quite
quite the opposite
um I would say that
part of the the challenge though is
that
if we look at all objective measures if
I measure your sleep and the sleep of
your wife
if when you're sleeping separately
versus when you're sleeping together
it's very likely that objectively you
will both be sleeping worse when you're
sleeping together that's what the
science tells us however what's
interesting is that when you survey
people and say how satisfied are you
with your sleep which is a subjective
measure people will say I'm actually
more satisfied with my sleep when I'm
with my partner than when I'm sleeping
alone so there's a mismatch here
objectively your sleep is better but
subjectively you still prefer that and
of course it's natural you know we there
is safety there's Security in
co-sleeping there is this
sort of connection that we get you you
can approach it if you want just be
honest with yourself
and be honest with your partner
and you can start by saying look this
isn't forever
I just want to say Let's do an
experiment for a week
10 days let's let's just try it and see
how it goes it doesn't need to be
permanent because what you actually miss
are the book ends of sleep
for the most part the two of you are not
conscious for most of the experience of
sleeping together
it's really getting into bed instead of
having a kiss or a cuddle or and sort of
waking up together in the morning and
sort of now obviously when you're a
mismatched chronotype that's also it can
be a challenge too so you can still have
a sleep divorce but you can set up a
system where you will go in and you'll
say your good nights and you'll kind of
get into bed have a kiss and cuddle and
then you Retreat to a separate location
and you can repeat that same process so
I I don't want to sort of believe at the
point of a of a sleep divorce but um
people can certainly explore there is
something called a halfway house which
is called the Scandinavian method which
sounds far more salacious than it
actually is it's simply that you buy two
beds and you put them side by side in
the same room and therefore the amount
of disruption physical
um disruption that happens by way of
sheets and movement is decreased but
that doesn't solve it all sometimes
there is snoring uh sometimes there is
sleep talking those things are not
obviated by the Scandinavian method
when you think about where Society is I
was I was going to ask you you know you
said you wanted to to do the work you're
doing now for the rest of your life
um so do you think the work you're doing
now is going to become increasingly more
important and relevant
I.E is the problem gonna get worse or is
it going to become less significant and
less relevant based on the trajectory of
societies you see it
you know I'm
mixed I think when I wrote the book I
started writing uh
a book that was called why we sleep back
in probably about 2014 or 15 and at that
point sleep was the neglected stepsister
in the health conversation of that day
you know we were speaking a lot about
diet and exercise which was wonderful
but there was no voice of sleep
and I was so sad about that because I
could see so much disease and suffering
that was coming so clearly by way of a
lack of sleep but it wasn't there on the
public buffet menu for consumption of
knowledge and so that was part of the
motivation for trying to write the book
so I would say now
and this is not because of me or the
book or anything like that but is is
sleep more of a conversation in this day
and age than it was six or seven years
ago I think I would say yes there is a
greater awareness of of sleep
um
but with that awareness
I want I think one can still question
the pragmatics meaning
just because we're talking about it more
does not mean that people are still
failing to either get the sleep that
they need or that they are unable to get
the sleep that they need and those two
things are different one is that you are
healthy and you can generate the sleep
that you need but you don't give
yourself the opportunity time or life I
should say sometimes because it's
sometimes not your choice life does not
give you the chance to get sleep and if
only you had the chance you could sleep
that's one version the second version is
no I'm giving myself the right
opportunity to sleep but because I'm
anxious or because of other issues I am
not able to generate sleep I suffer from
insomnia and sleep problems
so those two things I don't see having
changed since you know I think this
public movement this increasing movement
of sleep conversation came on the table
so in that regard I'm more pessimistic
than I am optimistic and I think it will
only get worse if you look at rates of
insomnia for example they're only
increasing they're only escalating rates
of anxiety disorders the very same thing
and those two things are intimately
intertwined
so I think
I wish I my mission was extinguished
within the next couple of years because
Society started sleeping wonderfully
well I don't think that's going to be
the case so I think I've got my work cut
out for me
um to try and help people with better
sleep
um is it so it's getting we're getting
worse at sleeping
I think
modernity is making it so much more
difficult for us to sleep modernity I
think when you think about
we often think about sleep as a
biological process and it very much is
and but
also it's so environmental as well as
biological meaning
when you were to say you know how did
you sleep last night think about all of
the external factors that changed it
well I had to be up at this time I had
to catch a flight this time my partner
went to bed at this time and she woke up
at this time there was this noise that
sort of happened I'm now sleeping in a
hotel room you know there are countless
externalities and those externalities
are shaped by this thing called the
modern world and in the modern world if
I could really be cynical and I'm not
someone I'm very optimistic and I'm very
non-cynical but you could argue from a
capitalistic standpoint that Society
does not want you sleeping because what
Society wants from a capitalistic point
of view is that you're either producing
or you're consuming
and when you're sleeping you're neither
producing and you're neither consuming
and so
there are lots of ways that I think
society and the modern world has
conspired willfully or not
conspiratorially or not to
decrease and try to diminish sleep in
fact I think the CEO of Netflix several
years ago and I'm sure that YouTube
comments will correct me if I'm wrong
here but I believe his very statement
was that we are
we are deciding to commit war against
sleep
that was their goal
and it just stunned me that you know
that we're going to go to war with sleep
we're going to remove you from your
sleep so there are lots of ways in in
which I think Society does not help us
light is another good example we are a
dark deprived Society in this modern era
because we're exposed to light we are
not giving ourselves the right
temperature cues you know we go into an
office where it's you know 20 degrees at
70 degrees Celsius whatever it is stock
stable then we come home and we regulate
our temperature at home to be the same
thing
we take on board probably too much
caffeine in this day and age although I
am actually an advocate of drinking
coffee and I can explain why too but
anxiety as I said is a huge issue all of
these things are preventing and classic
roadblocks to sleep
any of us are getting the sort of
recommended daily allowance of sleep as
a percentage do you know it seems to be
about
um one third of most modern
civilizations are failing to get the
recommended seven to nine hours of sleep
a night one third so roughly 30 35 33
roughly yeah and it does that have
Geographic variants I in some countries
it's worse in some countries it's better
I'm thinking about the UK versus the us
or you know Japan or whatever yeah it is
and in fact you let me give numbers to
the three countries that you've
described uh here in the United States
the average amount of sleep that people
are getting is uh six hours and uh 29
minutes in the UK it's not much better 6
hours and 49 minutes Japan was the worst
six hours and 22 minutes now to be clear
that's the average what that means is
that there is still a large proportion
of that bell-shaped distribution
of people getting even less than that
amount now there are some countries that
you look at
um that are actually sleeping much
better than that I think let me um
Mexico for example is
um is doing very well if you look at
Mexico City uh people are actually
sleeping and not too far off from eight
hours so there is variability and we can
try to understand why which by the way
just brings me back while I think about
it to your comment of will my work be
done not from the because I'm a
scientist and I do I have a run a Big
Sleep Center at UC Berkeley but the work
I do as a hopefully a public advocate
for sleep why I don't think it's going
to change
um anytime soon is because
governments aren't really doing much
about it and I've tried as best I can
and if there is any government out there
that listens to this that wants to work
with me I'd be delighted
I don't remember and maybe you can but
any major first world nation government
that has had a public health campaign
regarding sleep
and it stuns me because those same
governments have had Public Health
campaigns regarding you know eating
regarding smoking regarding drunk
driving regarding risky behaviors safe
sex loneliness loneliness Mental Health
suicide
where is sleep in that equation
and it's such a fundamental ingredient
and in fact almost all of those things
that I've just described
have an intimate relationship with sleep
I mean suicide especially we we're
starting to do a lot of work with this
although it's been hard to get funding
but what we found is that insufficient
sleep is a precursor to Suicide that
sleep disruption seems to predict both
suicide ideation in other words suicidal
thinking suicide planning and tragically
suicide completion as well so if we were
to try to have governments create a
public health campaign to pull this
Archimedes lever on better sleep there
are so many other health benefits you
know sleep is the tide that rises all
the other health boats it's almost like
um
it's like a mixing deck in a studio you
know in those sound Studios where you've
seen it and then there's that one button
all the way to the end the white button
sort of that when you move it up instead
of all of the other dials the sort of
the red yellow orange green dots they
all move up at the same time as well
there's this like sort of one mess
there's like one ring to rule them all
which sleep is that Archimedes lever so
if governments could only execute on
that the health benefits would be
manifold in terms of their consequences
it begs the question you know if I were
to make you today president prime
minister whatever of the world and you
had to do you know just a few things to
really fix the
lack of sleep epidemic there you go
diagnosed it
um what would those things be if you
were in charge how would you redesign
Society to help us to sleep better
gosh it's such a good question and I've
thought a lot about this
it almost in Reverse which is to say why
is it that we are struggling to get
sleep and there is no single answer
there are so many different reasons and
that's why it's actually a very
challenging problem to solve
I would go through a descending level of
steps so first I would start at the
government level and we would get those
Public Health campaigns in order
next I would go to the professional
level because there we have this
mentality in business that you know
sleep is for the soft Among Us that
less sleep equals more productivity
and that is just not true and I can
provide you with all of the evidence so
we need to get rid of this sort of sleep
machismo attitude in the workplace where
we were where our badge of honor of
sleep deprivation on our arms we need to
get companies to actually start
embracing sleep and I can guarantee you
and I can give you all of the evidence
as to why if as a company as a CEO if
you start prioritizing the sleep of your
employees you will be far better off as
a company you will be more product based
and you will be more profitable and
revenue generating
sleep is the very best form of
physiologically injected Venture Capital
that you could ever wish for and in fact
the Rand corporation which is an
independent survey Corporation what they
found is that at a national level
insufficient sleep costs most Nations
about two percent of their GDP
so here in America that number was 411
billion dollars of lost profit caused by
insufficient sleep in the United Kingdom
it was over 50 billion dollars in Japan
it was over 120 billion dollars if I
could solve the Sleep loss crisis in the
workplace I could perhaps double the
healthcare benefit for many of those
countries or I could halve the out the
education deficit in those countries so
the next level I would Target is at
business then next step down would be
medicine
medicine is a classic demonstration here
we have Junior doctors or here in
America they have doctor residency
programs where people are working 20 30
hour shifts
and so already doctors are inculcated
into the mindset of the uselessness of
of sufficient sleep
across numerous countries and I think it
was maybe over eight different countries
we looked at the medical curricula and
we asked how many hours of education do
doctors get about sleep
and what's strange is that you know
often doctors you'll go in and you'll
have an appointment they'll say okay you
know how are you eating and you know
what's going on with the bathroom how's
the toilet and then you know how are you
sleeping as if sleep is one of these
Universal Health barometers but what we
found is that most doctors will only be
given about an hour to an hour and a
half of sleep education during their
entire medical school education which
blows my mind because it is one third of
the patients lives but they're only
given about 90 minutes of education so
no wonder your doctors aren't treating
your sleep problems thinking about your
sleep problems understanding yourself
it's not their fault and plus they're
sleep deprived anyway when they're being
trained ironically by the way
doctors Junior doctors who've worked a
30-hour shift when they finish that
30-hour shift and get back in their car
they are 168 more likely to get into a
car accident because of their lack of
sleep and and back up in the emergency
room from where they were just working
but now as a patient I mean this the
Paradox the irony just stuns me so I
next move down to the level of medicine
then I would go to education because we
don't get taught about sleep in schools
and I never got one of those special
classes you know I got sort of you know
sexual education classes classes about
drugs no one came in and told me about
the benefits of sleep why aren't we
doing that then next I would move down
into the family because there is
Prejudice in families with sleep it's
this notion of
parents of teenagers and these Teenagers
by the way it's not their fault they
have a shift in their chronotype in
their circadian rhythm that when they go
through puberty when they're going
through adolescence they get fast
forwarded in time so when they were
eight or nine years old they would be
going to bed you know sort of early in
the evening but now as teenagers they
seem to be stubborn and they're staying
awake staying awake until midnight 1am
and they won't get into bed it is not
their fault because they have a
biologically wired shift in the tendency
of when they want to wake up and when
they want to sleep why am I bringing
this up about this sort of
mismanagement in the home because
parents at weekends will go into the
room of the teenagers they'll you know
pull open the curtains they will pull
the covers off and they say you're
wasting the day you know and firstly
what they're doing is probably trying to
sleep off a debt that we've lumbered
them with during the week because of
this incessant model of early school
start times which I'll I'll come back to
but within the home if you ask parents
of teenagers what percent of parents
think that their teenagers are getting
sufficient sleep and about 70 of them
will say yes my teenager is getting
sufficient sleep when you look at the
data only about 15 of teenagers are
actually getting the sleep that they
need so what happens is a parent-child
transmission of sleep neglect they're
saying you're lazy you're slothful so
then what happens well in 15 20 years
time now that teenager has got a teenage
child what do they do they go back in
the room they rip the curtains open they
say you're wasting the day because
that's what they were told so we need to
break that down too and then finally we
need to come to the individual and we
need to solve the individual's sleep
problems so it's a very long answer and
I'm desperately sorry to a very big
question as to what I would do if I was
off for a day but I hope that gives you
some sense of of the depth that I think
we need to go to I've tried to think
about the question a lot it's not
particularly well executed I don't think
I was very eloquent there but I hope
that gives a sense it sounded perfectly
eloquent to me it sounded like a
Manifesto so
um hopefully if there are people
listening from governments which I'm
sure there are because you know I hear
about that sometimes which is quite
bizarre but um I
I'm sure they'll be getting in touch
with you very quickly going back to the
top of that that stag on the company
level so as a CEO or a CFO or an
employer whatever
um there are some companies that are
incentivizing their team members to
sleep right is there any data showing
the efficacy of that
is data that we have and it's
bi-directional both the efficacy of when
you increase sleep and also the
detriment when you don't allow sleep so
a great example was
um NASA back in the
1980s they were looking at using naps in
the astronaut program because when
you're up and you're orbiting Earth you
will actually be cycling Earth you know
really quite quickly and you will get to
see depending on the orbit maybe
somewhere between 10 to 15 sunrises
every 24 hours which sounds I mean
amazing and remarkable but trust me in
terms of your sleep it is very
dislocating
so they were looking at how to use naps
strategically to improve performance
because the weakest link on any space
mission and we've done some work with
NASA
um is the human being themselves and
they can cause catastrophic failure now
if you make an error at work and you're
here terrestrially on the ground you
know it's probably non-trivial make an
error when you're up in space it can be
a big deal so they were looking at that
and what they found was that these naps
anywhere between 20 minutes to an hour
could increase productivity on these
different tasks by about 34 and
increased General alertness by over 50
percent and in fact the data was so
powerful that it ended up being
transmitted to all of the terrestrial
workers on the ground that NASA would
start to in it was what was called NASA
naps it was a NASA nap culture now NASA
isn't desperately compassionate by any
means it's a great organized
but they just like companies like Google
or Facebook they understand the pounds
and pennies cents you know the dollars
and the cents version of productivity so
anything that returns productivity they
will invest in and some of those
companies you know I um I did some work
uh Google uh during a sabbatical and
there on their campus they will have
these nap pods and they will have these
what are called
rooms where you can go and you can take
a nap so think about 20 years ago you
would never imagine a company paying you
to sleep on the job if you have caught
sleeping on the job you'd probably be
fired now companies are incentivizing it
not because they are thinking
compassionately or empathetically about
the health or the wellness of their
individuals it is because they
understand that it transacts marked
productivity so NASA is a good example
when you give sleep you get something
back but I can go back to the reverse of
that
why we think that a lack of sleep does
not equal more productivity is for at
least five reasons first when you survey
and we've we can do these studies in the
in the laboratory too when you
undersleep employees they will choose
less challenging problems so if you give
them an array of work problems they will
just simply you know check email they'll
listen to phone messages they don't dig
into deep Project work second of the
problems that they do take on in their
work they will produce fewer Creative
Solutions and after all creativity and
Ingenuity are supposed to be the two
engines that drive businesses forward in
terms of their productivity in their
revenue
third that interesting finding that
we've discovered is that when underslept
employees start working in teams they
will slack off they won't do their work
they will let other people do their work
it's what we call social loafing so they
ride the coattails of other people's
hard work which won't breed a good
atmosphere in your company you know
trust me
the fourth thing that we found is that
underslept employees are more deviant
that they're more likely to fudge data
in spreadsheets they're more likely to
falsely claim uh money for reimbursement
that was inappropriate
the final thing is that a lack of sleep
will go all the way to the top of the
business chain what we found is that the
more or less sleep that a business
leader has had from one night to the
next to the next the more or less
charismatic that employees will rate
that business leader from one day to the
next to the next even though the
employees themselves they know nothing
about the sleep that that CEO has been
getting it's evidential in how
charismatic that CEO is
so you can add all of these things up
and no wonder you know
if you don't snooze you lose in the case
of business in that regard that's why I
can produce I think a non-trivial case
for business by the way the other aspect
that is hugely costly to businesses and
when I go and speak to businesses about
why they should value sleep
if you offer it on the grounds of again
sort of compassion or mental health
probably don't want to listen when you
convert it into the cost of the company
and how much it's fleecing them in terms
of their profits then they start to pay
attention
underslept employees will take on
average about 11 more days uh sick days
throughout the year relative to
well-slept individuals so you're
essentially just paying people
additionally for 11 days of work that
they will never give you when you are
under sleeping them secondly the
utilization of Health Care Resources
increases by about 80 percent so the
cost to either you the company here in
the US where your company is paying for
your health care or the cost of the
government for example in the United
Kingdom is astronomical
and also then the co what we call
comorbid diseases your rates of obesity
diabetes cardiovascular disease mental
health conditions all of these things
escalate as underslept employees
continue to get even more underslept
so there is no strong case that I've
seen that leads me to think businesses
should foster the mentality of
insufficient sleep quite the opposite so
that's hopefully an answer to your
question we can look at it
bi-directionally when we give sleep back
do you get productivity yes when you
take sleep away the things implode
rapidly yes and is it costly to your
company very much so
on that point of naps and you know
Google sleep pods naps and things like
that there was a point in my life where
I because I learned about REM sleep and
the importance of REM sleeping deep
sleep and that happens a little bit
further on into my you know the 90
minute look at me trying to tell a Sleep
Experts well I love it but you see what
I mean like this is my very this is my
monkey brain so I didn't understand the
subject matter very well still really
don't to be honest but in the first it
takes me a significant amount of time to
get to Deep Sleep into REM sleep
how long on average would you say it
takes for it for some you know yeah so
you will probably go into light sleep in
the first 10 to 15 minutes then you'll
go down into deep sleep you'll stay
there for about 30 40 minutes and then
you'll start to rise back up and you'll
pop up and you'll have a short REM sleep
period and then you complete the non-rem
to REM cycle after about 90 minutes and
back down you go again down into non-rem
and up into REM so on average for human
beings it's 90 minutes so I therefore
assumed that napping really does nothing
because I thought well it takes me so
long to get to REM sleep and to deep
sleep that there's if I've got 15
minutes 20 minutes to to nap it's just a
waste of time right was I wrong or was I
right
you were
understandably wrong okay good I'm happy
because I I've always rejected naps
because I thought they don't matter
because it takes me so long to get to a
restorative State anyway so so we've
done lots of different studies with naps
we and other colleagues uh too and what
we found is that naps can transact some
fantastic benefits they can improve
cardiovascular health lower blood
pressure they can improve your learning
and memory abilities they can reset the
emotional
north of your magnetic compass in a good
way where you can de-escalate negative
emotions and increase positive emotions
um so naps certainly are a good thing
but with a big caveat that I'll come
back to
um yes you're right in the sense that to
get a full cycle of sleep and to get
into REM sleep you would probably have
to make that nap about 90 minutes and in
fact a lot of the cities that we do we
will use a 90-minute nap duration of
time so that the brain can cycle through
all of those different stages of sleep
but you don't need to nor would I
suggest that you do
what we found is that different stages
of sleep perform different functions for
the brain at different times of night
there are actually four separate stages
stages one through four increasing in
their depth of sleep so stages three and
four are those really deep stages of
non-rem sleep stages one and two that's
the lighter form of non-rem and then you
have rapid eye movement sleep or what we
think of as dream sleep and people will
sometimes say to me how do I get more
REM sleep or how do I get more deep
sleep I might response to them is why do
you want to get more REM sleep and their
answer is what isn't that the good stuff
and it turns out that there is no good
stuff it's all good stuff you know maybe
with the exception of that light stage
one non-rem sleep that's shallow sleep
and we typically don't like to see too
much of that but stage two non-rem sleep
three and four they all have their
different functions that we've
discovered and REM sleep has its
functions so you need all of them you
can't Short change any of them but for
nap
what we found is that you can get nice
benefits for things like your learning
and your memory and it can even reduce
some level of anxiety up to about 20
minutes you can in fact you can nap I
think the study one of the studies they
brought a nap down to about nine minutes
in duration and there was still some
basic improvements for your sort of
General level of alertness and reaction
time for example if you're an athlete
that's that's non-trivial
so um so the reason I would say
be careful with naps is for two main
um sort of suggestions the first is try
not to nap for about longer than 20
minutes because once you go past 20
minutes you really start to go down into
those deeper stages of non-rem sleep and
if you wake up after about 45 minutes or
60 minutes
it's not a problem I'm not suggesting
that you shouldn't or you couldn't I'm
just saying be aware because when you
come out of that deep sleep and you wake
up from that deep sleep normally that's
not how you wake up you will usually
wake up out of lighter stages of sleep
or out of REM sleep it's rare that we
wake up out of deep sleep but if you nap
and you snap for about 40 minutes you'll
probably go down into deep sleep and at
that point where if you wake up and your
alarm goes off then you're going to feel
almost miserable and worse than you did
before the nap because you have what's
called Sleep inertia which is
essentially a sleep hangover where the
brain is still sort of pulled back into
that deep sleep State and it can take
you almost an hour before you feel like
you're back up to operating temperature
and you're up to Motorway speed so I
would say keep it to 20 minutes and you
don't suffer too much of that inertia
you still get some nice benefits also
don't nap too late in the afternoon
also the final part is if you are
struggling with sleep at night if you're
someone who has insomnia or sleep
difficulties do not nap during the day
it's the worst thing that you can be
doing because when we're awake during
the day we build up a sleepiness
chemical in our brain it's called
adenosine
and the longer that we're awake the more
adenosine that builds up the more
denosine that builds up the sleepier and
sleepier that we feel
and when we sleep the brain gets the
chance to clear away all of that
adenosine all of that sleepiness and
somewhere between seven to nine hours
after sleeping a full night the brain
has evacuated all of that sleepiness
chemical of that adenosine so that then
we should wake up and we should feel
refreshed and restored and not needing
caffeine to function
why is that relevant to naps well it's
relevant to naps because when you take a
nap you're essentially it's like a
pressure valve on a cooker you're just
releasing some of that healthy
sleepiness that you've been building up
and therefore if you are struggling with
sleep at night and then you nap during
the day it's terrible because you're
taking away all of that healthy good
weight of sleepiness that we've been
trying to build up on your shoulders to
give you the best chance of a good night
of sleep
that's why I would say if you are
suffering from insomnia don't nap during
the day also even if you are if you
don't struggle with sleep at night try
not to nap after about 3 P.M in the
afternoon or 2 P.M
napping late in the afternoon or in the
early evening it's a little bit like
snacking before your main meal it just
takes the appetite off your sleep hunger
so try not to do that but naps for the
most part if you don't struggle with
sleep they are wonderful things just
keep in mind the 20-minute sort of idea
you mentioned caffeine there a topic
I've modeled over over and over again on
this show
um because as I've said to maybe three
or four of my guests now
it feels like caffeine is a miracle drug
that comes with no apparent cost but
when I think about things like anxiety
and I know shallow sleep States I've
always pondered that maybe caffeine is
playing a role in that you said you
you're you're Pro caffeine you're a
caffeine Drinker yourself
so I am not a caffeine Drinker myself
but I am Pro coffee oh okay and I'm I'll
tell you why I'm very thoughtful about
my wording between caffeine and coffee
there and to your point it's a it's
another astute one which is
it would you know is it a miracle drug
with no cost
in biology and Medicine There is almost
no free lunch
um and
that is true when it comes to caffeine
and sleep so
perhaps I'll give the skinny on caffeine
and how it impacts your sleep but then
Circle back around to what seems an
oxymoronic statement for me which is why
I'm still Pro coffee
um caffeine will hurt your sleep and
probably at least
three ways some of which you most people
are not aware of the first issue is the
duration of its action
so caffeine has what we call a half-life
of about five to six hours in other
words after about five to six hours half
of that caffeine is still in your system
what that means is that caffeine has a
quarter life of somewhere between 10 to
12 hours so if you have a cup of coffee
at noon at midday a quarter of that
caffeine is still in your brain at
midnight
so having a cup of coffee at noon and
it's hyperbole in truth probably or it's
a little bit hyperbolic but it's almost
the equivalent of a coffee at noon as
the equivalent of you know talking
yourself into bed and just before you
turn the light out you Swig a quarter of
a cup of coffee and you hope for a good
night of sleep and it's probably not
going to happen so that's the first
thing to keep in mind is that the timing
of caffeine
the second is that caffeine is a
stimulant now everyone knows this
everyone knows that caffeine can make
you more alert and more awake by the way
how does it do that
um it comes back to adenosine which is
the chemical that we spoke about the
sleepiness chemical it's no coincidence
that those two things sound the same at
the end of the name caffeine and
adenosine
caffeine will actually race into your
brain and it will latch onto the
adenosine receptors the welcome sites in
your brain and it has very sharp elbows
and it will force away the adenosine
from those receptors and it will hijack
those receptors now at this point you
may be thinking well hang on a second if
it's latching onto those sleepiness
chemical receptors shouldn't caffeine
make you more sleepy and the answer is
no because what it does is it just
latches onto the receptor and it
inactivates it essentially so it masks
the receptor
what caffeine does then is race into
your brain you've got all of this
sleepiness at 9 00 PM or 10 p.m you have
an espresso because you're trying to
power through and finish the report or
you know the presentation for your sort
of your pitch uh deck for your startup
company
and that caffeine races in it latches
onto the adenosine receptors
and blocks the signal of adenosine so
now your brain was thinking I'm starting
to get tired it's 10 p.m but now all of
a sudden that signal is blocked and a
caffeine is like hitting the mute button
on your television remote controller it
just mutes the signal of sleepiness so
now you think well no I don't feel
sleepy anymore and here's the danger
that even though well when the caffeine
is in your system and it's latched onto
the receptors that adenosine is still
there it's not going away in fact if
anything during the course of the
caffeine in your system it continues to
build and build
and now when the caffeine finally gets
metabolized and excreted out of your
system not only do you go back to the
sleepiness that you had many hours
before it's that plus all of the
adenosine sleepiness that's been
building up during that time in between
so you get hit with this huge tsunami
wave of sleepiness and that's what we
call the caffeine crash
so the one of the issues so that's sort
of caffeine in terms of how it works in
its timing another issue is that it
creates anxiety just as you said and
anxiety is probably one of the greatest
enemies of sleep it's one of the
principal reasons that underlies
insomnia is a physiological state of
anxiety that your fight or flight branch
of the nervous system is ratcheted up
that's what caffeine will do it needs to
do the opposite for you to fall asleep
that's why you can have what we call the
tired but wired phenomenon where you say
I'm so desperately tired I am so tired
but I'm just so wired that I can't fall
asleep it's because your nervous system
is too amped up caffeine will trigger
that amping up
then at that point if you're struggling
to fall asleep because you've got too
much caffeine on board it is what we
call anxiogenic so now you start to
worry
and the last thing you need to do when
your head hits the pillow for good sleep
is worry because when you start to worry
you start to ruminate and when you
ruminate you catastrophize and when you
catastrophize you're dead in the water
for the next two hours when it comes to
sleep because we have this sense that
you know things at night in the darkness
of night
are so much bigger than they are in the
brightness of day
and we start worrying you know in this
modern era we're constantly on reception
and very rarely do we do reflection
unfortunately the only time when we
typically do a reflection is when we
turn off the light and our head hits the
pillow and that is the last time you
want to be doing reflection so that's
the the second problem with caffeine
it's anxiogenic and it only makes you
sort of almost like the Woody Allen
neurotic of the Sleep World
the final part of caffeine is that it's
very good at blocking your deep sleep
so we've done a number of these studies
where we'll give people a standard dose
of caffeine let's say 100 150 milligrams
200 milligrams which is probably you
know a cup and a half of good strong
coffee
and then we put you to bed and we look
at the amount of deep sleep and it will
strip away your deep sleep by about
somewhere between 15 to 30 percent
now to put that in context to drop your
deep sleep by 30 I'd probably have to
age you by about 40 years for zero or
you could do it every night with an
espresso with with dinner and that's one
of the problems people will say to me
look I'm one of those people who I can
have two espressos with dinner and I
fall asleep fine and I stay asleep so no
harm no foul well not necessarily
because even if you fall asleep and you
stay asleep you're not aware of the lack
of the deep sleep that you're not
getting because of the caffeine and so
now you wake up the next day and you
think well I don't remember having a
hard time falling asleep I don't
remember waking up but now I'm reaching
for two or three cups of coffee the next
morning rather than my standard one cup
of coffee because I don't feel refreshed
and restored by my sleep because I was
lacking the amount of deep sleep and
deep sleep what does that Rob us of the
lack of deep sleep so lack of deep sleep
deep sleep is critical for regulating
your cardiovascular system it's the time
when we do replenish the immune system
it also regulates your metabolic system
so it controls the hormones such as
insulin that will regulate your blood
sugar and you will become blood sugar
dysregulated without sufficient deep
sleep upstairs in the brain deep sleep
will strengthen and consolidate and
secure new memories into your brain they
will prevent those memories from being
forgotten deep sleep is also the time
when we cleanse the brain of metabolic
toxins particularly the toxins that are
related to Alzheimer's disease so
getting a lack of deep sleep is I would
say a non-trivial thing in that regard
but
I don't want to be also puritanical here
and this is where I'm going to change my
title tune
I am not here to tell anyone how to live
their life I have no right to tell
anyone how to live the life I'm just a
scientist
all I want to try and do is gift you the
science and the knowledge of sleep so
that you can make an informed choice
and after all and the same is true for
alcohol too and sleep you know life is
to be lived to a certain degree
you know no one wants to be the
healthiest guy in the graveyard I don't
want to be that way too I want to live
life just with moderation the reason I
don't drink
uh caffeine is not because I'm so pure
technical I want to be the poster child
of good sleep I love the smell of
freshly ground coffee in the morning and
it's a great ritual it's just that I've
ruined my genetics and I am one of these
slow caffeine metabolizers so you can do
these genetic kits online and they will
tell you are you a slow metabolizer or a
fast metabolizer so that's the
variability that's why some people say
look I'm pretty immune to caffeine
others will say no I'm not
um why do I now favor coffee I was
actually quite
anti-caffeine and coffee when I first
came out with the book just looking at
the studies but now the data is
immensely compelling the health benefits
associated with coffee are undeniable
study after study after today and we can
put them all together in this big what
we call a meta-analysis study and it is
so strikingly clear that coffee drinking
coffee is a good thing for you from a
health perspective
two things to say about that the first
is that it's got nothing to do with the
caffeine
and a lot of people have sort of rightly
challenged me to say look you say how
problematic sleep can be when you're
drinking too much caffeine
but yet coffee is associated with many
of the same health benefits that sleep
is associated with but coffee is
supposed to hurt your sleep how do you
reconcile those two Matt Walker and the
answer is very simple antioxidants
because it turns out that the Coffee
Bean contains a whopping dose of
antioxidants things such as is what's
got other things such as Cafe style but
it's got a bunch of incredible
antioxidants probably the most powerful
of them in terms of the Coffee Bean is
something called chlorogenic acid now
don't worry it's not chlorine it's not
chloride it's not bleach chlorogenic
acid is very different
and what's happened in the modern world
is that we on we have and struggle with
our diet so much because we don't eat
enough Whole Foods Etc so what's
happened is that
the Coffee Bean has been now asked to
carry the Herculean weight of all of our
antioxidant needs on its shoulders
and where most people get the majority
of their antioxidants is by way of
drinking coffee that's why coffee is
associated with so many health benefits
it's not the caffeine case in point if
you look at the studies with
decaffeinated coffee you get very
similar health benefits again it's not
the caffeine it's the coffee itself so
the bottom line here is drink coffee but
I would say the dose and the timing make
the poison so try to limit yourself to
about two cups of coffee three cups of
coffee maximum because if you look at
the health benefits by the way it's a
dose it's not a dose response we're at
linear where the more and more coffee
you drink the more and more healthy you
become it Peaks at about two to three
and then actually starts to go down in
the opposite direction for lots of
reasons that we can speak about so
dose and the timing make the poison when
it comes to coffee so you drink decaf so
I do drink decaf so I will drink coffee
just because I love the smell and I do
enjoy the taste of it but I drink uh
decaffeinated coffee
I would love to drink a caffeinated
coffee too because I
you know I'm sure it would be
interesting because I work out every day
and I work out every morning and so many
of the health coaches that I speak with
and health professionals say you know
you should definitely get a shot of
caffeine and boost your workout and
actually the data on that is pretty
clear too that you're lifting for
example in the gym and your metabolic
activity is stronger when you've had
pre-caffeine doses but it's also
stronger when you sleep so but exactly
and that's the problem so and sleep is
I would argue much more beneficial to
health and if you're trying to work out
or you're trying to be an athlete or
perform
sleep Will trump caffeine five ways till
Tuesday I mean sleep is probably the
very best legal performance enhancing
drug that we know of that not enough
athletes are abusing
as you might know the show's now
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other sort of ongoing stereotypes that
I've always wondered if it was wrong or
right or whatever now I get a chance to
ask you is about this culture of sleep
medication so I've got some friends who
who might have I don't know prescribed
sleep medication but I've got a lot of
friends also that use
what they call sort of natural they
always use the word natural natural
something so it's like natural sleep
tablets yeah what's your perspective on
this culture of us of humans taking
sleep tablets to get them to feel sleepy
and go off to sleep at night usually
when people ask me that question
personally I the first thing I ask them
is why is it that you think you're not
able to sleep
and try to reverse engineer the question
from there before we even start thinking
about sticking Band-Aids on wounds I
firstly want to ask what's causing the
infection because we can keep bandaging
it for all we like but if it keeps
festering it's probably not going to go
away anytime soon is there a problem to
keep bandaging it it is a problem right
now we don't typically Advocate sleeping
pills as the first line defense agent
against or for insomnia as a treatment
in fact in 2016 the American cult and
again this is me simply describing the
science this is me being descriptive of
the science not prescriptive in terms of
medicine because I'm not a medical
doctor
um
but in 2016 the American College of
Physicians they had a expert panel who
surveyed all of the literature on
classic sleeping pills and what they
suggested was that sleeping pills must
no longer be the first line treatment
for insomnia it has to be cognitive
behavioral therapy for insomnia or we
call cbti which is a psychological
intervention that we can speak about but
their recommendation was that they found
I think their wording was small and of
questionable clinical importance in
terms of the benefits of sleeping pills
now there is a time and a place
for in clinical medicine for sleeping
pills but usually as an adjunct in
combination with cognitive behavioral
therapy they are not advocated for
long-term use but so they're usually
advocated for short-term use weeks
most people have been on them for months
if not years these classic sleeping
pills and that's a problem because those
sleeping pills are in a class of drugs
that we call the sedative hypnotics
and sedation is not sleep
for some subset of some people there are
some of these quote unquote sleep
supplements that may benefit but overall
the studies are very clear none of them
are efficacious
and when you think about it it makes
sense if there was some cheap sleep
supplement that you could buy on Amazon
that was the shangri-lar of good sleep
that was this miracle sleep drug
don't you think that a pharmaceutical
company would have patented it 20 years
ago and be making billions of dollars
from it you know that alone tells you
all that you need to know about you know
these natural sleep supplements
cognitive behavioral therapy for
insomnia though seems to be the kind of
the front line of
prescribed defense against a lack of
sleep in so many conditions what exactly
is that therapy aiming to do what like
what does it do for for somebody
great question so in some ways that the
title tries to suggest what it what it
does but not particularly well perhaps
so it focuses on cognitive aspects and
it focuses on behavioral aspects
so for the cognitive aspects when we do
cognitive behavioral therapy working
with the patient we'll try to focus on
thoughts and beliefs and ideas around
sleep do they have anxiety around the
bedroom most of them do I can't sleep
because I can't sleep so every time I
walk into the bedroom my bed is the
enemy and I look at the bedroom I look
at the bed and I just know that that
means I'm going to have a bad night of
sleep so what's happened is that at that
point your sleep controls you
and you've lost all confidence in your
ability to sleep and we need to course
correct that so one of the things we do
in cognitive behavioral therapy is that
we lower that anxiety and we say look
everyone has a bad night of sleep even a
bad couple of nights of sleep in fact I
will tell you I don't sleep perfectly
well all the time too I've had at least
two very severe bouts of insomnia in my
life
we all have a bad night of sleep it
doesn't mean that tomorrow you're going
to wake up with depression or
Alzheimer's disease don't worry you're
not going to get cancer you know just
because you've had a bad night of sleep
so we start to change people's
misbeliefs about sleep and we try to get
them back from being catastrophic about
this idea of my not sleeping
so we that's the cognitive aspect we
start to lower their anxiety around the
bed and and the bedroom we start to try
to build confidence back we start to
reduce their expectations about you know
what is reasonable sleep well right now
you're getting four or five hours of
sleep and we can do better but don't
start thinking that you need to get
eight hours of sleep straight out the
box let's just manage it that's just
because it's going to stress you out
right it's only going to make matters
worse right okay you know when you're
struggling with sleep in the middle of
the night and you're Wide Awake you're
laying in bed and you're thinking oh my
god I've got five hours left before I've
got to go to work it's the last you know
it's a little bit like trying to
remember someone's name the harder you
try the further you push it away
so would you say and that's what do I do
in that situation you it's 2 A.M in the
morning you've got to be up at seven
there's a flight you're getting on so
whatever yeah what should one do because
from what I was reading in chapter 14 I
was I was hearing that maybe I should
get out of bed or not just sit there and
ruminate
you know into the early hours of the
morning or do I stay in bed and do
something what does one do the
prototypical recommendation is that
after about 30 minutes of time a week
you should get out of your bed and you
should just go to a different room and
do something like you know read a book
or listen to a podcast don't eat because
it then trains your brain to wake up to
do that don't stop working or getting in
front of a computer screen you know I
said listen to a podcast sure you know
just make sure your phone's in you know
you don't start scrolling any more than
that but you can do relaxing things
stretch meditate
the reason is because if you start to
spend a lot of time awake in your bed
your brain is an incredibly associative
device and very quickly it will start to
learn that this thing called your bed is
this place where I'm always awake and
therefore you start to learn through
this repeated Loop of behavior that I'm
always going to be wide awake in bed and
we need to break that Association and
that's why we say get out of bed after
about 30 minutes because you're just
training your brain to think that this
thing called my bed is the place where
I'm never asleep and we want to break
that and only return to bed when you're
sleepy and there's no time limit for
that and that way gradually it's much
better because you will relearn the
association that your bed just as when
you were young is guaranteed that your
bed is this place where you will always
be asleep
the problem with that is many people
don't want you know it's the middle of
the night it's dark it's cold I'm not
I'm just not going to get out of bed so
what's your other what what else have
you got in your toolbox Matt
um at that point I would say okay that's
reasonable
the first thing I would suggest is
meditation
you know I am a hard-known Scientist and
when I was researching that the book
I was you know I just thought this
sounds all a bit woo-woo and you know I
uh live and work in Berkeley California
which is kind of you know the Free
Speech you know flower power movement
San Francisco flowers and you have
business I just thought this is all of
it you know holding hands and singing
come by ours this is not for me this
this meditation stuff I couldn't get
away from the strength of the data it
was immensely powerful regarding sleep
and its benefits on insomnia and sleep
so I started meditating and uh now I
meditate for 10 minutes before bed every
single night and I've been doing that
for about four years so I would say if
even if it's in the middle of the night
and if I wake up in the middle of the
night I'll start trying to walk myself
through a meditation
um
you reference their listening to
podcasts etc etc you know doing
something else to stimulate the brain I
when I go to bed I have to have
something playing I say have to I
shouldn't be that definitive I like to
have something playing some kind of
sound or noise whatever and much to my
partner's dismay my content of
preference is
serial killer
podcasts or documentaries or just like
something which is really going to grab
hold of my brain and focus me so
something like it has to be really
interesting to me for me to be able to
focus on it my partner is the opposite
again she likes um silence
why do I listen to serial killers it's
different for different people's
constitutions yeah yeah and public
psychologies uh and you know I can
pathologize to you or you like if if you
would wish me to but I would say it
what's fundamentally going on here with
meditation and I'll come back to an
alternative too but the reason why some
meditation apps as well have now started
to do what's called Sleep stories which
in some ways is what you're doing a
version of with your podcast
is Hawks back to when we were kids you
know for many parents they would just
read a book to the kid you know the
children's books good night books
because you would read the child to
sleep
and for some reason
we as we developed into adults we
thought well we no longer benefit from
having a story read to us to help our
sleep
no it's not true we we benefit hugely in
fact the the meditation company calm you
know was saved by the the introduction
of sleep stories into their app they
were doing pretty well as a meditation
app but then they started to do sleep
stories and it became a unicorn company
um in terms of its valuation it broke a
billion dollars and it was on the the
back of sleep stories and what they
realized is that people were
self-medicating their insomnia by way of
meditation so they latched on to that
and then they found that these stories
sleep stories were great and you've got
now wonderful people people who you've
interviewed on the show so what you're
doing and what those sleep stories are
doing and what meditation is doing it's
all the same thing which is that it is
taking your mind off itself
because when you are struggling to sleep
or you've woken up in the middle of the
night
what you don't want to be doing is
focusing on either what you what you
what did I do today what did I not do
today what did I do poorly oh my
goodness what have I still got to do
tomorrow and at that point things are
just a disaster you're Wide Awake
what all of the things that we've just
discussed do is they take your mind off
itself
and at that point then you start to
allow sleep to come back naturally
that's why one of the other suggestions
is take yourself for a mental walk so
don't count sheep by the way that
doesn't work if colleague of mine at UC
Berkeley did the study actually takes
you longer to fall asleep if you're
counting uh sheep what she found at Dr
Allison Harvey was that if you just
close your eyes and you think about a
walk that you take frequently let's say
it's a walk with the dog and you think
about it in High Fidelity detail so I
close my eyes I go out the door take a
left down the steps then I'm going to go
up the street I take the first left past
that pine tree that's the level of
detail if you just walk yourself on that
mental walk sure enough people fall
asleep in about 50 less time half the
time it takes this is the thing with
sleep stories and also my serial killer
documentaries or serial killer podcasts
that I listen to
detail exactly you get even I've
listened to
calms sleep stories before and the
attention to detail in the sort of
descriptive nature of what they're
saying is so apparent they'll say things
like the cold wet window sill saw the
raindrops like
um tapping against it one by one by one
by one and that sounds very similar to
my serial killer documentaries when I
hear about the serial killer coming in
through the window yeah yeah yeah at
night time
um and I wondered why the descriptive
nature of it the detail matters for
dozing us off and because it prevents I
mean you've got limited bandwidth in
terms of cognitive capacity right and if
you're consumed and you saturate your
bandwidth with that level of detail it's
very hard for any of these other things
called our worries and our anxieties to
start entering into our mind the other
thing I would note by the way though is
if you are if none of these things are
working for you if the fictional notion
of Serial killing is not working for you
if meditation is not working for you if
going on a mental walk is not working
for you
this is the final suggestion I have if
you're lying there awake firstly by the
way if you're struggling with sleep
remove all clock faces from your bedroom
to one of the best pieces of advice I
can give you
knowing what time of night it is is no
favor so knowing now that it's 3 23 am
in the morning and I'm still struggling
to fall asleep and then I look back at
the clock and it's now 403 am and I've
still been awake and now it's 4 27 and
I've got to wake up at 6 30 a.m knowing
that
has no utility for you remove all clock
faces from your bedroom it is a gift
but coming back to the final suggestion
if you don't want to get out of bed if
you don't want to listen to a podcast
the final thing I would say is just
accept and say look it's okay tonight is
not my night it is not the worst thing
in the world and instead of trying to
sleep
all I'm going to do here is lie in bed
and I'm just going to rest
because wouldn't it be lovely if someone
came to you in the middle of your work
day you're just stressed and someone
said by the way just come into this room
there's a bed here just lie down and
just rest for an hour wouldn't it be
lovely just have a good old rest for an
hour just rest there
and I would say that if you can't sleep
just lie in bed stop worrying about
sleep and not being able to get it stop
worrying about the next day just lie in
there and enjoy a nice good old rest
and by the way usually what happens is
that after you start thinking okay I'm
going to rest the next thing you
remember is the alarm clock going off at
6 30 because finally you stop trying and
sleep happens so of course you know
prolonged one of the things I've also I
wonder if this is a if I'm wrong about
this is I sometimes thought that you
know I could go Monday to Friday and
kind of sacrifice my sleep this was
specifically when I was really in the
height of like running big businesses
Etc
um and then on the weekend I'll just
make up for it
so I thought you know I could go Monday
to Friday I'll sleep maybe sometimes two
hours a night three hours a night
whatever then Saturday you know I'll
just do a you know 11 hour sleep and
I'll just make up for it yeah
is that a good strategy
the delightful laughter at the end of
your sentence that uh I think probably
tells you the answer that you know
um unfortunately sleep doesn't work like
that it would be nice if it did sleep is
not like the bank in other words you
can't accumulate a debt
as you were doing during the week and
then hope to try and pay it off at the
weekend
um so for example let me take an extreme
version of that experiment let me take
you tonight I'm going to deprive you of
sleep for an entire night for let's say
eight hours of sleep and then tomorrow
night I'm going to give you all of the
recovery sleep that you want as much as
you wish for and then the next night you
can have all of the recovery sleep that
you want and even on the third night
will you sleep longer that first
recovery night after a night of No Sleep
absolutely you will sleep longer
but across those three or four recovery
nights of sleep will you get back all of
the sleep that you lost not even close
you'll maybe only sleep back about four
four and a half of the eight hours that
you lost in other words by that stage
you are four or three and a half hours
in overdraft on your sleep bank account
you went into debt and you only paid
about 50 percent of it back so what's
happening with you during the week is
that you're accumulating this debt you
know of maybe 10 hours you should change
and you're only sleeping like six hours
a night for the five nights during the
week and then you binge on sleep and you
try to maybe sleep 10 hours or 11 hours
that's only two or three extra hours so
some total that's only four to six you
know hours of made up sleep
relative to the 10 hours of debt so what
happens is that that next week you now
carry forward four hours of your debt
and then next weekend you try to sleep
it back but you're still four hours lost
so now you've got eight hours of net
debt in other words what it develops is
into a compounding interest on a loan it
just starts to escalate ballistically
across weeks across years and across the
lifespan and then what happens in terms
of
Health outcomes so say that I did that
for a couple of years say that I
sustained that pattern of you know
depriving myself of sleep throughout the
week maybe catch up on Saturday yeah
depriving myself again the next week
catch up on Sunday deprive myself the
next week and I did that pattern for
multiple years what would be the health
implications so you can describe them
short mid and long term
the first thing I would say though is
that the elastic band of sleep
deprivation will stretch only so far
before it snaps
the short-term you know probably the
most immediate short-term consequence is
that you are popped out in a driving
related accident drowsy related accident
because drowsy related accidents are
non-trivial they make up a large
proportion of accidents on our streets
in terms of human errorful driving when
you say popped out
of the gene pool
okay so what happens is that when you
are under slept you're at the wheel and
you start to have what we call Micro
sleeps where your eyelid will partially
close now you are not aware of it you
have no awareness of it whatsoever and
in fact parts of your brain seem as
though they're almost falling asleep
like you're having this micro sleep and
it lasts for about a second or two
seconds now if you're on the motorway
and you're traveling at 70 miles an hour
and you have a two second micro sleep
that's enough time for you to drift from
one lane into the next if you're just in
a two on a two-lane you know sort of
back street where there's oncoming
traffic in the other direction and
you're traveling at 40 miles an hour and
you drift half the way into that lane
that's oncoming traffic so in other
words if you have a micro sleep at 60 or
70 miles an hour at that point there's a
two-ton missile traveling at 60 miles an
hour and no one's in control and that
may be the last micro sleep that you
ever have in your life
obviously all the other things you've
mentioned would be implications things
like performance drop sort of memory
relationships libido would all drop off
so I wouldn't be having as much sex I
would like all those things then midterm
so midterm then you're going to escalate
those things into more disease state so
for example if I were to take an
individual and uh people have done these
studies not not we but um where you
limit them to let's say four or five
hours of sleep for one week your levels
of blood sugar are disrupted so
significantly that your doctor at the
end of that one week would classify you
as being pre-diabetic
so that's you could almost argue that
short term not mid-term
um you know one if you're a male and I
limit you to four or five hours of sleep
a healthy young male
um for one week I will drop your levels
of testosterone to that of someone who
is 10 years older than you so I can age
you by a decade just by short sleeping
you for one week we see equivalent
impairments in female reproductive
Health in estrogen luteinizing hormone
and follicle stimulating hormone
um so it's both men and women
your blood pressure will start to creep
up your systolic blood pressure in
particular will creep up your heart rate
in terms of its contraction rate in
other words your speed of your heart
starts to increase the progression into
obesity diabetes
cardiovascular disease mental health
issues anxiety depression suicidality
all of these things immune compromise
infection
all of those things can be termed you
know will be midterm now all of those
things have a longer term tale to them
which is this thing called premature
mortality so using that sweet spot of
seven to nine hours of sleep you can
argue that there's a simple truth on the
basis of the data the shorter your sleep
the shorter your life that short sleep
will predict all-cause mortality is that
supported by the by data that's
supported by data now there's an
interesting change there which is once
you get past about 9 or 10 hours your
mortality risk doesn't just keep going
down and down it will hook back up again
as if almost too much sleep is a bad
thing and we can explain why that is the
case as well and why it's probably not
quite as simple as that but the final
long-term consequence that I would say
is Alzheimer's disease you know the two
most feared diseases in developed
nations are cancer and Alzheimer's
disease both of them have links to
insufficient sleep many of them causal
and this relationship between sleep and
Alzheimer's disease this is where we
actually do I'd probably say almost 50
of the work that I do at my sleep center
is focused on sleep and Alzheimer's
disease
and there the data is stunning I would
say at this stage insufficient sleep
seems to be one of the more or one of
the most significant lifestyle factors
that can develop or dictate the
development of Alzheimer's disease later
in life now that's a lifestyle Factor
there are other genetic factors but
certainly we now know that it's not just
that insufficient sleep
predicts a greater amount of Alzheimer's
pathology in your brain so for example
people who on average are sleeping six
hours or less have a far higher
magnitude of amyloid of beta amyloid
which is the sticky toxic protein
related to Alzheimer's disease and
another protein called Tau protein these
are the two protein culprits of
Alzheimer's both of those are escalate
the less and less sleep that you have
now that's just associational we also
know by the way that two Sleep Disorders
insomnia and sleep apnea heavy snoring
both of those are associated with a
marked increased risk of your
Alzheimer's disease of Alzheimer's
disease later in life that's simply
associational that doesn't prove
causality but we now have the causal
evidence both in animal models and in
human models if I deprive a human being
of sleep for a single night or I even
just deprive you of deep sleep for a
single night the next day we can see an
immediate increase in these Alzheimer's
disease related proteins circulating in
your bloodstream circulating in what we
call a cerebral spinal fluid that bathes
the brain and using special brain scans
we can even measure it within the brain
itself
so these are causal manipulations it's
not associational I manipulate this
thing called sleep and the consequence
is that I manipulate your Alzheimer's
disease proteins
that's correlation going to causation
then the question is well mechanism
what is it about sleep when you get it
that is de-escalating Alzheimer's
disease risk
in other words when you don't get it
what why would it increase your
Alzheimer's risk and this is a stunning
discovery made by a scientist called
Macon nedergaard at the University of
Rochester here in America and she found
three things first studying mice and
rats she found that the brain has a
cleansing system now we didn't used to
think that your brain had a cleansing
system your body had one and everyone
knows what it's called it's called the
lymphatic system
um we didn't think the brain had one but
she discovered that the brain has one
it's called the glymphatic system named
after these glial cells that make it up
the second thing that she discovered is
that that cleansing system within the
brain is not always switched on in high
flow volume across the 24-hour period it
was expressly during sleep and
particularly during deep non-rem sleep
when that sort of sewage system was
pushed into overdrive and washed away
all of this detritus that built up
during the day
and the final thing that she discovered
and this is why it's related to
Alzheimer's disease is that two of the
metabolic byproducts that build up
during the day in our brain
are beta amyloid and Tau protein
the two Bad actors in Alzheimer's
disease so in other words what she
discovered is a system of you know good
night sleep clean that sleep is a power
cleanse for the brain
and if you're not getting your sleep
every night you know it doesn't mean
that you're going to get Alzheimer's
disease next week it doesn't mean that
you're going to get Alzheimer's disease
you know in a year's time
but night after night once again it's
like compounding interest on a loan and
that's why we now believe through this
causal mechanism that insufficient sleep
is a risk factor for Alzheimer's disease
lots of people will say to me look there
are these individuals in society who
claim that they you know didn't need
very much sleep who didn't sleep a lot
you know Margaret Thatcher has often
quoted me uh quoted to me about that you
know
um
uh Ronald Reagan was apparently another
short sleeper
I don't think it's coincidental that
both Thatcher and Reagan went on to die
of the unfortunate disease of
Alzheimer's
I'm sold
sleep is important I get it I'm sold
how do I
my question is what are the things that
in the modern society are standing in
the way of sleep we've touched on some
of them Loosely but some of the like big
obvious things the things that you would
suggest doing very actionable things we
could do straight away to improve our
chances of having that healthy
um deep sleep that we need to be um
optimal in every regard of our health
and performance
there's probably I think five standard
tips what we call sort of sleep hygiene
that you can do and then I'll come on to
maybe just some unconventional tips that
we've sort of touched on and we've
spoken about many of these the first
thing I would recommend people to do and
this is why when some people say how
what about this new sleep supplement or
you know it's it's 40 quid for this
bottle of these the new sleep natural
medication so I'm going to give it a try
I would say try these tried and true
things first before you spend your money
on supplements the first thing is
regularity go to bed at the same time
and wake up at the same time no matter
whether it's the weekday or the weekend
your brain expects regularity it thrives
best in the conditions of regularity
when you give it regularity you can
improve the quantity and the quantity of
your sleep the second thing is get some
Darkness at night as I said we don't get
enough darkness in the modern world
and so the trick I would offer and I
don't use it I don't like the word hack
but the suggestion would be in the last
hour before bed
try this experiment for everyone
listening for the next week
dim down half of the lights or switch
off half of lights or even three
quarters of the lights in your home in
the last hour before bed all of the
lights in every room in all of the rooms
you know switch off almost all of the
light now I'm not suggesting be unsafe
and walk around in the darkness in the
last hour that's not everyone's saying
just dimmed out you know switch off half
of the lights
you will be surprised at how sleepy that
Darkness will make you feel and it's
also an incredible behavioral trigger
to signal to your brain that it is time
for sleep that darkness is around me
that's the second tip is Darkness the
third tip is temperature
most people sleep in an ambient bedroom
temperature that is too high
and you need to aim for bedroom
temperature of about 18 18 and a half
degrees Celsius around about 65 to 68
degrees Fahrenheit if I'm probably
butchering the the mathematics there on
that but
um you need to get cool now you can wear
thick socks you can have a hot water
bottle that's fine but the ambient needs
to be cold
because you need to drop your core body
temperature and your brain temperature
by about one degree Celsius to fall
asleep and stay asleep
and it's the reason that you will always
find it easier to fall asleep in a room
that's too cold than too hot so make
your bedroom cold make it dark like a
cave
that the fourth question would be sort
of what we've or fourth suggestion would
be Walk It Out and we've spoken about
this the 30-minute rule you know get up
do something different or meditate you
know don't lie in bed awake for too long
then the final two things we've spoken
about well we've spoken about caffeine
we haven't spoken about alcohol but let
me just say as the kind of headline of
it alcohol is not a sleep aid many
people use it as a sleep aid it is not
your friend alcohol again is a sedative
so it knocks you out the second is that
it fragments your sleep so you wake up
your sleep is littered with all of these
small Awakenings most of them you don't
remember because there's too brief but
it makes for miserable lousy quality
sleep and the final thing is that
alcohol is very good at blocking your
REM sleep or your dream sleep which we
know is critical for many other
functions as well so alcohol's not your
friend that's the sort of the final tip
again you know just every if you're with
friends have a glass of red wine just
know okay my sleep's not going to be
great thank you
I'm joking you know I'm not yeah
it's just you know live life too of
course I'm not saying that I I was I was
thinking there about the other sort of
Behavioral things that we do that harm
our sleep as well we talked about coffee
earlier on avoiding that weird that
people drink it after dessert in the
evening so yeah never understood that
because that's an old tradition
um but the other thing obviously that
the modern generation are even more
susceptible to is to
have a quick tick tock
the social media account or something
now I thought you know there's a lot of
different products out there that are
trying to help with the the light that
comes from these screens that I think is
the cause of what's keeping us awake but
there's this little button called Dark
mode on my iPad there's also one called
night shift so if I just pop that on
Bob's your uncle and I can crack on with
my screen time
true or false
partly true oh good okay so I can just
pop that on night mode in dark mode and
then I can carry on using my iPad
partly true
so it turns out that the blue light from
screens does have an impact on sleep so
there's a great City done by Harvard
Medical School by some colleagues there
and they showed that reading for an hour
on an iPad just before bed relative to
just reading a book in dim light firstly
it delayed the time with which people
fell asleep so it took them a lot longer
to fall asleep second it reduced the
total amount of sleep that they had
third it decreased a sleep-related
hormone called melatonin it delayed the
release of that melatonin and it reduced
the amount of melatonin and finally it
reduced the amount of rapid eye movement
sleep so it had significantly
significant the Melatonin Point
significantly so it delayed the release
by about somewhere between 90 minutes to
two hours across the individuals so in
other words your brain wasn't so what
melatonin does it's a it's called the
hormone of Darkness or the vampire
hormone just because not be because it
makes you want to bite into being next
because it signals to your brain that
it's night time that it's Darkness and
so your brain needs the signal of
melatonin for it to understand when is
it dark in other words it needs to
understand by way of melatonin when it
is time to fall asleep and when you're
bathed in electric light at night and
especially when you're getting blue
light from these devices your brain is
fooled into thinking it's still daytime
and when there is light emitting through
your retina coming into your brain it
signals to a part of your brain to hit
the brakes on melatonin and your brain
will not release melatonin so what was
happening with this iPad reading is that
you are artificially telling the brain
it's still daytime and the brakes on
melatonin were still shut on and so
melatonin was not starting to be
released until much later
and what was it also interesting about
the study by the way is that when they
stopped the iPad reading the Sleep
disrupted pattern continued for several
days later in other words it was almost
like a drug that it had a washout period
that was a blast radius to it now
there's been some great work by a
wonderful sleep scientist in Australia
Michael gradazar and he is added to this
story and he said it's not just the blue
light these devices the principal
function of these devices is that they
are attention capture devices just like
you said I'm just going to have a wee
little Tick Tock before bed
they are in the attention economy and
all they care about is capturing your
attention for current currency and they
make a lot of money from it
what that attention does is that it
stimulates your brain and when your
brain is stimulated it's very difficult
for you to fall asleep and it creates
what we call Sleep procrastination where
you're lying in bed and you could be
perfectly sleepy and you could fall
asleep right now
but then you sort of check social media
and they think oh I'll just shoot that
last email and then I'll order that last
thing on sort of you know Amazon and
then you get a text back from your
friend and you start texting them and
and then you look up and it's now an
hour later and you're an hour deficient
on sleep so it's the activation of your
cerebral cortex by these devices that is
perhaps the more harmful aspect of them
regarding your sleep now
here again I don't want to be finger
wagging you know the genie of technology
is out the bottle and it's not going
back in any time soon there's nothing
that I'm going to say as a sleep
researcher that's going to change that I
don't take my phone into my bedroom
I put my phone uh out in the kitchen I
don't see it until morning but lots of
people do and fair enough but there's
another rule uh that I've stolen from
another friend called Michael grandner
who's uh here in America at the
University
um of Tucson in Arizona he has this
Great rule regarding technology and it's
the following that if you really must
take your phone into your bedroom
you can only use it
standing up
and what you'll find is that after about
six or seven minutes standing up you
think I'm just gonna I'm just gonna sit
down on the bed and at that point as
soon as your backside hits the bed
you're done you've got to put the phone
away I think it's a great rule of thumb
if uh if you need to take technology in
the bedroom
um I'm going to apply that the other
thing I wanted to ask was about sleep
and weight loss had a lot of Health
experts on this podcast recently but
none of them have really talked to me
about the role that sleep or sleep
deprivation plays in
wait
is there a relationship
it's probably one of the most well
defined relationships that we know in
all of sleep science
and it is at least a three-part story so
the first emerging evidence came in
terms of hormones so there are what we
call appetite regulating hormones and
the two principal ones of concern here
are something called leptin and ghrelin
now leptin when it's released will
signal to your brain that you're
satisfied with your food you are
satiated and you are no longer hungry
Lin does the opposite when ghrelin is
released it says no you're not satisfied
with your food you are not full you
still want to eat more you are still
hungry
and some of the first studies they
started to just limit people restrict
people's sleep to six hours or five
hours or four hours and what they found
was that um there was
firstly that signal leapt in that says
no you're satisfied with your food you
don't want to eat anymore you're full
that signal of fullness satiation was
decreased by 18 percent
if that wasn't bad enough ghrelin which
is the hunger hormone that lapped up by
28 percent
overall hunger levels Rose by about at
26 percent
so firstly you are it's almost like
double jeopardy that you are getting
punished twice for the same crime of not
sleeping enough once by losing the
signal of I'm full
I I don't want to eat anymore and once
again for the no I'm much more hungry
and I'm just going to overeat which is
ghrelin
so what that produces is a profile of
increased eating so on average
underslept individuals started to eat in
those studies about three to four
hundred extra calories at each sister at
each sitting by way of insufficient
sleep
then what they discovered is that it's
not just that you want to eat more it's
what it is that you have a craving for
when you are under slept
and this is the problem what they found
is that when you are under slept you eat
more of everything but you especially
eat more of these heavy-hitting stodgy
carbohydrates bread pasta pizza
the the next thing that you started to
eat have a preference for was simple
sugary Foods sweets and chocolate and
then finally you started to Crave very
salty food and high sodium food intake
will increase your blood pressure
so that was the first of the the three
mechanisms then we did a study where we
said perhaps it's not just the
circulating hormones in the body the
brain is the ultimate Arbiter of your
food decisions so what's going on in the
brain so we took a group of perfectly
healthy individuals and we put them
through the experiment twice once when
they'd had a full eight hours of sleep
and once when we deprived them of sleep
and the next day we place them inside an
MRI scanner and we showed them images of
lots of different foods that range from
being sort of you know very healthy to
being very unhealthy and sort of ice
cream and you know chocolate and pizza
and things to Leafy salads and nuts and
greens and vegetables and we asked them
to rate how much they wanted that food
for each item now we did something a bit
just sort of dastardly to make it more
ecologically correct so that they
weren't just saying okay they probably
think I should probably say that's
healthy we said we're going to randomly
select one of these image which is these
food images that you see and after you
get out the brain scanner we're going to
give you that food and we're going to
politely ask you to eat it all so it
made it a bit more realistic so the
choices were more you know as much as
that we could
so what we found is that when they were
sleep deprived the Deep hedonic centers
the emotional centers of the brain these
desire centers these reward centers they
ramped up in their activity in response
to these highly desirable highly
unhealthy Foods
so these more basic sort of you know
guttural parts of the brain as it were
these reward centers were lighting up
much more strongly when you're sleep
deprived worse still the impulse control
regions in the front of the brain what
we call the prefrontal cortex they were
shut down they were taken offline so as
a consequence you lost your impulse
control and that's why you start to then
say you know when I'm sleep deprived at
the food sort of buffet I'm not I'm not
going to do salad I'm just gonna that
pizza looks awful good or that pasta
with the cream I'm just gonna go into
that all go so
so you're it's what we call a pattern in
terms of brain activity in Neuroscience
of hedonic eating that your brain goes
into this hedonic desire profile so now
we understood it's not just hormones in
the body it's also changes in the brain
then came the finding that there's
another chemical in the body that's
responsible
and this comes on to cannabis
when people
um
when people when people that you may
know have smoked uh cannabis they'll
often say I get
viciously hungry I get the munchies I
get really hungry that's no coincidence
because cannabis will stimulate appetite
now we all have naturally occurring
cannabis compounds in our brain and our
bodies they are called
endocannabinoids Endo meaning comes from
insiders
whereas the Cannabis that comes
externally when you sort of smoke it or
take edibles
so
endocannabinoids do many things for the
brain and the body but one of the things
that they do is control your appetite
and your hunger and what we found is
that when you sleep deprived individuals
these naturally occurring
endocannabinoids rocketed up by over 20
percent
cranking up people's appetite
and so these three ways lead you to stop
hacking on you know when insufficient
sleep is occurring when sleep gets short
your waistline typically starts to
expand and we Now understand the reasons
if that wasn't bad enough
the last thing that we discovered is
that
let's say that you're trying to be
really careful and you're trying to diet
and you're trying to lose weight
if you're not getting sufficient sleep
then 60 of all of the weight that you
lose will come from lean muscle mass oh
God and not fat not the muscle I know
exactly so in other words when you are
dieting but you are under slept you lose
what you want to keep which is muscle
and you keep what you want to lose
just fat
so again it's I'm sold not an ideal
situation my last question for you in
fact was of all the subject matter we've
talked about
what is the most interesting thing we've
missed in your view the thing that you
think is most pertinent or interesting
or significant or perks people up or
sits them on the end of their chair when
you discuss it
I think the only other area that
fascinates people even more than sleep
is dreaming hmm
so dreaming above and beyond the stage
of which it comes from which is
principally called rapid eye movements
they put dream sleep REM sleep provides
a set of physiological and uh benefits
but dreaming we've now discovered even
above and beyond that provides benefits
and it provides at least two benefits
the first is creativity I was telling
you that during deep sleep you cement
individual memories you grab memories
and you shift them from a short-term
storage Reservoir to a long-term storage
Reservoir and you strengthen the circuit
of those memories so you future proof
information but that's individual
memories what we discovered is that
sleep is much more intelligent than you
ever thought possible that it's during
REM sleep and particularly during
dreaming that we take all of the
individual pieces of information that
we've been learning and we start
interconnecting them and associating
them with all of our back catalog of
stored information
and so what dreams the one of the
functions of dream sleep is to
cross-link and Associate new memories
together so you wake up the next day
having After Dream sleep with a revised
mind web of associations and those are
capable of divining solutions to
previously impenetrable problems
so think of dreaming as it's almost like
informational alchemy that you start to
fuse things together that shouldn't
normally go together
but when they do they cause marked
advances in your thinking in your
productivity in your Ingenuity and in
that way you go to sleep with the pieces
of the jigsaw
but you wake up with the puzzle complete
and I would argue that that's the
difference between knowledge which is
remembering the individual pieces
and wisdom which is knowing what it all
means when you fit them together that's
one of the functions of dreaming it's
the Reason by the way that you've never
been told to stay awake on a problem
yeah
um the other function of dreaming that
we know of is that dreaming provides a
form of emotional first aid
that we've we've done a lot of work and
we came up with a theory that was called
Dreaming as overnight therapy
and what we've discovered is that when
we go into dream sleep particularly
based on its neurochemical profile and
its physiological anatomy of the brain
um the dreaming brain will take
difficult painful experiences sometimes
traumatic experiences and it will
essentially strip away the bitter
emotional rind from the informational
orange so let's take a step back what
makes a memory emotional what makes a
memory emotional is that at the time of
the experience that experience triggered
a strong visceral reaction and that
visceral reaction is useful to the brain
and it wraps that experience in this
blanket of what we call emotion it red
flags it and prioritizes it in the brain
so now you've created a memory of an
emotional event in other words you've
created an emotional memory
but what dream sleep does is then it
takes that useful emotional memory and
it will Detox the emotion from the
memory it strips the bitter emotional
rind from the informational Orange it's
almost and that's why we called it
overnight therapy so that the next day
you come back and now you feel better
about those experiences so you have a
memory of an emotional event but is no
longer emotional itself you don't
regurgitate that same visceral reaction
that you had at the time of learning so
the brain has done this elegant trick of
stripping the emotion from the memory
so it's that's this that's the second
benefit
um is that it provides
it's not time that heals all wounds it
is time during sleep and particularly
during dream sleep that provides
emotional convalescence it's funny
because there's a stereotype that we
should never go to bed angry at each
other
you will wake up far less angry as a
consequence
Matt we have a closing tradition on this
podcast where the last guest asks a
question for the next guest not knowing
who they're gonna ask it for
um the question that's been left for you
from our previous guest obviously they
didn't know who they're leaving it for
but uh it's a very I love these
questions when they're challenging
um
what is the biggest way in which you are
a contradiction
a gosh I'm a contradiction
in so many ways I think
I'm a contradiction in the sense that
within my profession with this field of
sleep I feel very comfortable I'm
reticent to say confident but I am very
comfortable to get on stage you know
give a TED talk in front of a couple of
thousand people and my heart rate will
be very stable I probably
I probably don't feel I feel more myself
on stage alone in front of thousands of
people
than I do at any other time in my life
that's where I feel most myself
but yet I'm a contradiction because off
stage
I'm very insecure
I am very much an introvert I'm very shy
um I don't like being the focus of
attention
and so those two things I've often
wrestled with but the more people I've
spoken to sort of now being out in the
public sphere and sort of
sort of being more in this sort of
public intellectual realm you start to
meet you know very famous people and you
meet you know musicians and
and what you learn is that they're very
similar that they say that they become
this version of themselves on stage and
then when they're off stage they are a
radically different person but I am such
a contradiction in that sense I feel
very comfortable and very secure on
stage in front of thousands of people
and for many people public speaking is
one of the most anxiogenic things you
can ask anyone to do but for me heart
rate is probably in the you know mid 40s
uh very relaxing for me but then put me
in a room in a small room of a couple of
people my heart rate's probably through
the roof and I've become very
introverted so I'm a contradiction in
that sense
um
yeah
Matthew thank you thank you for making
the time today I've I've wanted to speak
to you for many many years and you
absolutely never disappoint anybody so
you're it's really kind of you to say
it's exceptionally important work and as
you said at the start of this
conversation we often neglect the
medicinal properties of a great night's
sleep over things like diet and medicine
or exercise whatever whatever else it is
but your your voice and the the passion
that sits behind it has led a a charge
in society which is waking us up no pun
intended to the um the virtues and the
power and the importance of having a
great night's sleep but in a nice way in
a way that I find a really empowering
and actionable and that's the most
important thing so thank you for that
Matthew thank you and thank you for
saying that last part especially I I
don't think I can
um lay claim to that sort of early on I
think I'm doing much better as much
better I'm doing a little bit better as
a public communicator and being less
puritanical and dictatorial in my sleep
message I think it did a terrible job
coming out I'm learning and I'm being
more sensitive but I'm always lovely to
hear feedback from folks about what I'm
not doing well because I would love to
do this better and better if I can but
thank you for saying those kind words
and thank you again for having me on
giving me this opportunity to speak I
now will anoint you as a sleep
ambassador from this point forward so
thank you so much again Stephen thank
you so much
[Music]
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[Music]
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[Music]
Ask follow-up questions or revisit key timestamps.
This podcast episode features neuroscientist Matthew Walker discussing the critical role of sleep in physical and mental health. Walker explains why sleep is an essential 'elixir of life' that benefits immune function, memory, emotional stability, and toxin clearance in the brain. He addresses misconceptions about caffeine and alcohol, explains how to handle sleeplessness through techniques like CBT-I and meditation, and clarifies that 'sleep debt' cannot be simply recovered on weekends. The conversation also explores the impact of lifestyle choices, including diet and technology, on sleep quality.
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