Why sleep matters now more than ever Matt Walker

great to be here with everyone it a

really important conversation today I

think because I don’t know about you

Whitney but they’ve been Knights in the

last couple weeks where I just haven’t

slept that well right there’s just a lot

of stress there’s a lot of worry that’s

a lot of uncertainty and and so forth

and that meet with you ask absolutely I

feel like my sleep has been a little

less than ideal lately for sure probably

for a lot of you out there too I’d

imagine

yeah no indeed so though we’re very

lucky to have with us today like the

perfect speaker for this he’s professor

of neuroscience and psychology at

Berkeley in California and director of

the center for human sleep science

author of a book three years ago why we

sleep and last year gave a TED talk

who’s been seen nearly ten million times

now so it’s a it’s a treat to invite ya

Matt Walker thanks Whitney

you’ll be back right Whitney I’ll be

back with questions from from your in a

bit hello Matt how are you I am good

Chris and how are you doing and thank

you so much for having me on well thank

you it’s very good to have you here I

mean I guess I guess that’s going to be

the first question on top of people’s

minds is you know is there a case that

sleep matters now more than ever I think

firstly it’s important for me to to not

necessarily feed into people’s anxiety

regarding sleep I know as you mentioned

there asleep is difficult for some

people when anxiety is high and of

course that’s never more so at present

so what I would say is that if anything

that we’re talking about feels as though

it’s a trigger feel free just to come

back at a time that feels better in

terms of that anxiety level

in terms of sleep and covered 19 right

now we don’t necessarily have any

evidence to suggest that there is some

kind of a link between those two but

certainly what we know is that there is

a very intimate relationship between

your sleep health and your immune health

I’ll give you just a couple of examples

and there was a study some years ago

that demonstrated that individuals who

reported getting less than seven hours

of sleep and had almost a three-fold

increase likelihood of becoming infected

by the rhinovirus which is what we all

think of as the common cold relative to

those who are getting eight hours of

sleep or more there was another study in

over 50,000 women and what they found

was that individuals who were getting 5

hours of sleep or less had a 70%

increased risk for developing pneumonia

which is a respiratory lung infection

relative to those who are getting 8

hours of sleep or more um but I think

perhaps one of the most striking results

in this relationship between sleep and

immune health was a study where they

demonstrated if you’re not getting

sufficient sleep in the week before you

get your flu shot you produce less than

50% of the normal antibody response

therefore rendering that vaccination

significantly less effective do I think

particularly actually on that last point

at some point we will develop a vaccine

for kovat 19:00 and then the question

becomes is the same thing true if you’re

not getting the sleep that you need in

the week before you get your Co vid shot

will that immunisation become

significantly less effective I actually

think that’s an important question that

we will need to answer in the future ok

so no specific evidence how could there

be this is a fairly there’s a new threat

to humanity but given that you know in a

way the you know if someone gets

infected there follows this sort of epic

battle between a virus and their immune

system it’s it’s obvious common sense to

give your immune system every shot it

can and every chance it can and in many

other cases sleep is known to

do that so they haven’t really met

matters now it’s up there I think it I

think certainly from immune health

perspective we know that sleep

essentially sharpens every tool in that

box sleep essentially restocks the

weaponry in your immune Arsenal giving

you the greatest chance to fight off

infection and I think as of at least

April 2020 we don’t have that evidence

yet I know that there are a number of

studies however that are looking at that

even some of the sleep tracking

companies are trying to rally efforts

around that and examine this right now

so we will have the data I’m sure well a

little later in this interview we’re

going to dig into how to sleep better I

know you’ve got a lot of interesting

advice in that regard but before we go

there let’s let’s spend a bit more time

thinking about the different ways that

it can be really helpful now because

paradoxically and we actually many of us

have in theory at any rate more time to

sleep that we’ve ever had and so boy if

we could put that to use how else how

else could it help us just during our

waking day and the things that we’re

having to focus on now

sleepers seems to provide a benefit to

almost every major organ system in the

body and many of the operations of the

mind and perhaps I’ll just give two

examples within the mind one of the

things that we know sleep is essentially

incredibly beneficial for is learning

memory and even creativity and when it

comes to memory sleep is important in

perhaps at least three ways firstly we

know that you need sleep before learning

to actually prepare your brain a little

bit like a a dry sponge ready to

initially absorb new memories and lay

down those new memory traces but that’s

not enough you not only need to sleep

before learning to imprint those

memories into the brain

you also needs leave after learning to

essentially cement those new memories

into the neural architecture of the

brain so that you don’t forget um and

certainly there’s very good evidence for

that in fact sleep almost performs a

file transfer mechanism where it takes

memories and shifts

them from a sort of a short-term

vulnerable reservoir to a more permanent

long-term storage site within the brain

and that’s what we used to think that

sleep was beneficial for taking

individual memories and holding onto

them as it were future proofing that

information but we’ve since discovered

that sleep is actually much more

intelligent than that leap will actually

take new memories and start to integrate

and associate them with pre-existing

stores of information so it’s almost a

little bit like memory alchemy at night

so that you wake up the next day with a

revised mind wide web of associations

and that leads to remarkable states of

creativity there’s lots of good examples

for this that he’s in that laboratory

showing that um sleep can inspire almost

a three-fold increase in creative

insights and it’s probably the reason

that you know you’ve you’ve never been

told to stay awake on a problem but

instead you’re you’re told to sleep on a

problem and I think that phrase seems to

exist in almost every language that I’ve

inquired about today which means that

this creative benefit of sleep

transcends cultural boundaries comment

across the globe that is one of the most

mind-boggling things to hear about how

you can be worried about something or

puzzled about something and you wake up

in the middle of the night and suddenly

you know possibilities pop into place

the answer is there and that the fact

that you look in one way it’s kind of

knowing because it means your

unconscious mind has been there somehow

you know with I guess pre associating

and doing things that you were supposed

to do all by yourself and it’s not fair

but in other ways it’s this is it’s

super core and so you’re saying that

there’s like how the three times the

creative output very curious as to how

that’s measured but I mean that that’s

that’s an amazing pain if you if you

have enough if you have enough sleep

yeah so there’s a lovely study done by

some German researchers a couple of

years ago and the way that they did this

they gave people a series of problems

that had a hidden embedded rule into it

and they never told them about that rule

but through exposure perhaps gradually

you can divine that hidden insight that

is sort of locked into that problem and

then they bring them back and then they

test them at some point later to see if

the lightbulb moment has gone on for

those individuals and they’ve defined

that sort of creative solution that

hidden rule and you can do that after

being awake or you can do that after

being asleep and that’s how they can

start to tease apart is it just time

that the brain needs for creativity is

it time awake or instead is it time

asleep and it was time asleep that

seemed to give to the brain this sort of

creative genius ability and I think

something else you mentioned there

that’s interesting too it’s not just

creativity but sleep can also I think

change our emotional and mood state sort

of feeling better the next day and

that’s what we’re now starting to learn

is is another function of sleep for the

mind that sleep and provides almost a

form of overnight therapy that sleep

will take those difficult stressful

situations or problems and sleep almost

acts like a nocturnal soothing balm just

sort of taking the sharp edges off our

emotional experiences so that we come

back the next day and we don’t feel as

challenged or as triggered by those

events anymore um so it’s not

necessarily I think time that heals all

wounds it’s time with a night of sleep

that provides that form of emotional

convalescence and that’s perhaps

particularly important in this modern

era I think there’s a lovely quote by

the American entrepreneur Joseph E

Cosman and he said the best bridge

between despair and hope is a good night

of sleep and I think that’s particularly

prescient right now I mean you could let

me imagine that a lot of people right

now wrestling with various mental health

issues that are possibly exacerbated by

the day that we’re in and I guess what

I’m here saying is don’t forget the

simplest therapy of all which is just

enough that that that in itself

yes sleep I think we’re learning

performs a form of emotional first aid

as it were and it reminds me actually of

another lovely phrase by charlotte

brontë who said that a ruffled mind

makes for a restless pillow and i think

we’ve all had that experience of feeling

that have triggered that that day and we

just know that sleep isn’t necessarily

going to come at night it’s probably

also the reason sorry just gone no

you’re going yeah I was just going to

say I think it’s it’s part of the the

reason that we’re finding that sleep is

so tied into psychiatric disorders and

mental health conditions in the past 20

years for example we’ve not been able to

discover a single psychiatric condition

in which sleep is normal so I think

sleep has a very powerful story to tell

in our understanding and probably

treatment of serious mental illness I

mean there’s another issue that I

suspect a lot of people are wrestling

with right now is that a lot of people’s

response to being isolated and feeling a

bit stressed is to imagine more and more

delicious things to eat and cook people

you know we will we go to comfort food

is is and so some people you know what

if they’re they wrestle with weight

issues even more now they’re normal

I think you’ve argued that sleep has a

role to play in in the battle against

gaining weight it does and you know I

think very understandably right now that

that may also be relevant

we know that helpless mechanism plays

out where if were not sleeping well we

can start to gain weight the first piece

of evidence concerns hormones and to

specific hormones that control our

hunger levels those two hormones are

called leptin and ghrelin and I often

say that they almost sound like hobbits

but I promise you they’re not they’re

actually sort of real hormones now

leptin when it’s released is the signal

to your brain to say you’re full you’re

satiated you don’t want to eat it

anymore

whereas ghrelin does the opposite it

says you’re not full you’re not

satisfied with your food you should eat

more and when we start to understand in

opposite directions we lose the signal

that says you’re full and you’re

satisfied with your meal which is leptin

but we increase the hormone that says no

you’re actually hungry even though

you’ve just eaten you you should eat

more and so as a consequence people who

are underslept can start to eat

somewhere between two to four hundred

extra calories per day when you look at

some of these studies umm it’s not by

the way just that you start to eat more

it’s also that when you are under slept

your preference for different food

groups actually shift and so you start

to desire more heavy-hitting

carbohydrates and more simple processed

sugary foods rather than those more

healthy macro ingredients which also

sort of sets you on a path towards a

more we call obesogenic profile but it

also actually changes how your brain

operates in response to food and we did

a study a couple of years ago where we

give people good night of sleep or we

kept them awake for a night and then we

place them inside an MRI scanner and we

showed them different types of food

groups and things that were very

desirable ice cream chocolate etc or an

sort of healthy leafy greens and what we

found is that when people were not

getting the sleep that they needed the

sort of the deep hedonic centers of the

brain were actually ramped up in

response desire to desirable foods and

they started to want those more

unhealthy foods and this in part was

because the the frontal lobe in their

brain which almost acts like this sort

of CEO of the brain regulating and

controlling our impulses and our our

emotions that was actually switched off

by a lack of sleep and so now you start

to reach for those unhealthy food

choices but I think we can think of that

more positively and say perhaps sleep

can actually be a tool in your box that

can enable you to

manage your weight more efficiently

incorrectly and so getting that extra

sleep should lead to and that’s what we

see in the data hopefully a profile of

body weight yeah I suspect speaking

personally there’s no amount of sleep I

could have that could make me lust after

broccoli but actually chargrilled was a

bit of olive oil and salt it’s not so

bad

so someone listen to this I mean if you

were trying to take a positive stance of

this isolation time or whatever thought

you know I’m gonna make this a time of

learning and of creativity and so forth

I mean that’s a possibility of someone

what what you’re saying is don’t forget

you’re gonna do that don’t forget to

make sleep a key part of that program

that’s gonna help on every account

that’s right it is a time like no other

were I think we have in some ways more

sleep opportunity time and in fact there

was a recent report out and it’s not a

scientific report so we have to be

careful not to over interpret it and

they looked at 68,000 Americans and

using sleep tracker data sort of

wearable track of data and they looked

at the change in sleep since March 13th

which was when the president mandated a

national state of emergency and what

they demonstrated or suggested was that

since then there’s actually been almost

a 20% increase in sleep time on average

as a nation here in the United States

now again I think we have to be very

careful it could be that people are just

sort of sitting in bed and you know

working or watching television in the

evening but even if it’s half that

amount I think what it may tell us is

that this time is very strange era that

will appear again right now as unmasked

what is otherwise a chronic persistent

debt in our sleep and finally you know

when you remove the breaks on sleep you

can see that sleep flourishes in return

now I’m not suggesting that that’s true

of everyone I think when we look at that

data more closely we’ll probably see two

clouds of data one

out of data where people are perhaps

sleeping more but then there will be

this opposite cloud where people

actually are sleeping significantly less

because of the things that we’ve spoken

about anxiety about the virus itself

concerns for example about whether they

all hold their jobs and people of course

magically have lost their job and so I

think we’ll see shifts but that seems to

be an interesting trend it’s interesting

I was having a conversation with friends

last night about how surprising the

final health statistics coming out of

this whole thing may look because if

people they have mostly be being

isolated so they’re not catching all the

other diseases they might be getting I

think I think flu stats are way down

compared to a typical year at this point

probably because of the isolation less

road deaths less who knows what else I

mean just possibly the there’ll be some

compensation for the horrifying death

rates that we’re going to see from kovat

but it’s you know it’s so interesting

trying to put those pieces together and

here’s here’s what is also interesting

to me like one of the key symptoms of

this virus is to make people incredibly

tired like a fever and incredibly tired

and I I’ve like it’s striking to me that

in principle we see those things as this

is awful things that happen that though

those are the viruses weapons actually

that in a way they’re not right there

are bodies weapons to try to beat the

virus we have a fever to try and burn it

off you I think that’s medically correct

that’s the body’s natural response with

a lot of hydrogens and home and with

sleep

should we just view like if you if

you’re having symptoms and you’re

feeling really tired

does it help at all to say this isn’t

the bug this is me and to listen to your

body into it and so just and to get or

the sleep you down more can I think it’s

a beautiful example and it’s another

demonstration of that relationship that

we spoke about I think everyone knows

that when you get sick or you get a

common cold what you really want to do

is just curl up in bed and and sort of

sleep sleep it off as it were and in

fact we understand that relationship

that when you

I’m infected there are a set of change

the immune factor that only go to were

to try and fight these infections but

they actually will signal to sleep that

sleep in it’s in in terms of its

duration is needed in greater amounts in

fact there are immune factors that are

sleeps stimulating factors because the

body knows that the best effort sort of

the most empowered custom that it can

call up in its weaponry defense against

infection is this thing called sleep and

that’s why we actually feel as though we

want to sleep more it’s not just because

we’re at home and we’re not at work and

we have the chance to sleep more it’s

that your immune system is actually

co-opting and bringing sleep into the

equation to help fight that infection

because sleep is so powerful in that

regard they’re given all these reasons

why we need more sleep now than ever

behaves talk to us about how how to get

it what are you’re putting on top tips

on how someone can get a really great

night’s sleep

yeah I think beyond the typical what we

call sleep hygiene factors such as

controlling your light in the evening

making your room a cool place also being

mindful of caffeine and all like give

three tips for what to do if you’ve had

a bad night of sleep and then if you’re

still struggling with sleep three tips

for perhaps how to better manage that um

so firstly if you’re coming off a bad

night of sleep the first thing and this

may sound counterintuitive particularly

coming from someone like me is not to

sleep in the next day you resist the

urge to sleep in wake up at your normal

time and there are two reasons for that

firstly your body has a 24-hour clock

and it expects regularity and it thrives

best on regularity and if you start to

change your wakeup time you will confuse

that 24-hour clock so try not to confuse

it wake up at the same time even a

a bad night of sleep the other reason is

that if you sleep in late you’re

probably not going to feel sleepy until

later that following evening so once

again you start to drift forward in time

the second piece of advice that relates

to that don’t necessarily go to bed any

earlier than you would otherwise

because sometimes if you do that even if

you’re feeling quite sleepy you can then

lie in bed and you can start to toss and

turn so try to push through until your

standard bedtime that following evening

the final piece of advice after a bad

night of sleep is resist the urge to nap

during the day now if you are healthy

good sleeper and you can nap regularly

then naps are just fine but if you are

struggling with sleep and have had a bad

night of sleep

try not to nap especially late in the

afternoon because you can think of naps

in that situation almost like snacking

before a main meal if you have a snack

you’re not going to have the same

appetite to try and sort of consume that

main meal and the same is true if you

start to snack with a nap just before

your main sleep so try to resist that

what to do if you are still struggling

with sleep I think the first thing is if

you’re in bed and you’ve been awake for

let’s say 20 or 30 minutes perhaps the

advice is take a break stop trying to

fight sleep because typically the harder

that we try to force ourselves to sleep

the more stressed and anxious that we

become and the further that we push

sleep away from us and you know it’s

it’s a little bit like trying to

remember a name where you’re sort of the

harder you think the the less likely it

is that you are to recall that name

don’t try to step away from that again I

think the advice here would be you would

never sit at the dinner table waiting to

get hungry so why would you lie in bed

waiting to get sleepy and the answer is

that you shouldn’t I’ll just get out of

bed go and do something different in dim

light read a book listen to a podcast

only return to bed when you’re sleepy

and that way you’ll read

the association that your bed is the

place of sleep refusing listen to a few

TED Talks I will put you to sleep okay

yeah yeah my voice I think and my inane

words are usually the best sort of

soporific name known to err to women and

men and I think the last two pieces of

advice beyond and that really is a

powerful one is is just please stop give

yourself a break and stop trying that

can be really helpful because you know

otherwise if you’re in bed you’re

stressed and ruminated you’re teaching

your brain that this thing called the

bed is the place with where instead we

train it to when you return understand

that the bed is the place where you

always sleep when you have confidence in

sleeping the last two pieces of advice

have a winddown routine I think many of

us have this idea that’s the perhaps

should be like a light switch that we

get into bed and we can just go from a

one to a zero that it’s a binary that we

can just switch off and instantly fall

asleep the typically is not like that

sleep is much more like trying to land a

plane that you’ve got to gradually give

it time to descend down onto that terra

firma of good sleep and the faster that

you’re going in terms of the mind the

longer that you need to give and the

mind to sort of gradually come back down

into sleep do the Wow meditation is

useful also taking a hot bath or a

shower having some kind of ritual and

that’s useful by the way not just

because a hot bath will relax you but we

also have this science and sleep called

the warm bath effect where as you come

out of the bath and although the blood

has come to the surface of your skin and

when you get out you radiate all of the

heat out of your body so your core body

temperature actually drops and that’s

actually good for sleep it helps you

fall asleep faster and stay asleep and

more deeply the last quick point I would

make if you are struggling with sleep

and it’s a simple tip that can be

effective remove all clock faces from

the bedroom it’s fine to have an alarm

clock but try to

take away any information about time

because if you’re struggling with sleep

knowing that it’s 2:15 a.m. or 4 a.m.

it’s not going to help you so remove

those from the bedroom the last thing I

would note by the way is that if these

things are not working well for you and

this is tip from a wonderful sleep

clinician called Michael grander 5

minute an athletic coach trying to give

you tips for improvement but you have a

sprained ankle

then nothing I can tell you is going to

be useful until you fix that that

sprained ankle and what I mean here is

that if these things aren’t working for

you it could be that you have an

underlying sleep disorder and if that’s

the case these tips really aren’t going

to be effective until you go and connect

with the doctor and see if you have an

underlying sleep disorder that has been

undiagnosed Whitney oh there are a lot

of people chiming in with questions all

over the world and like there are a

number of our viewers who are really

appreciating what you’re saying and are

struggling with sleep themselves and and

one of the questions we’ve seen is

around stress as it relates to our sleep

cycles and our dreams also just what

impact can stress have on the kinds of

dreams we have and and are our sleep

cycles in general so stress within the

body causes a number of different

changes one of the things that stress

will do is elevate a hormone called

cortisol which it’s often thought of as

not just an activating hormone but also

a stress-related hormone and typically

as we try to fall asleep

cortisol should actually be decreasing

beautifully and it should fall to almost

its lowest point right around the time

when we’re trying to fall asleep and so

if were stressed and if you in fact look

at the disorder of insomnia people start

to decline in their cortisol like a

healthy sleeper would do but just around

the bedroom period where you’re starting

to think about going to sleep cortisol

actually starts to spike back up again

and that can prevent people from falling

asleep it’s what we call sleep onset

insomnia

cortisol is one of the ingredients that

can impact our sleep in our sleep cycles

the other factor is the nervous system

in the body and in fact we have two

branches of your automatic nervous

system we have the fight-or-flight

wrench and then we have the more calming

what we call the rest or digest branch

of the nervous system and when we become

stressed and anxious we shift over more

into that sort of fight or flight

situation of the nervous system and we

also know that that means the depa

am pinned down in order to stay asleep I

think some people have had that

experience were that if mentally or even

in your eyes you feel tired and you know

that you’re tired but there’s just

something about you know your heart rate

and just the bodily stress despite the

mind being tired that is preventing your

body from falling asleep how do we think

about changing those well as I mentioned

you know the hot bath effect can help

meditation they’ll has also been proven

to be very useful meditation that

actually tries to shift you over into

that more quiescent state of the nervous

system and in people with insomnia and

mindfulness meditation techniques have

proven useful it reduces the time it

takes them to actually fall asleep so

those are some of the ways that we can

think about both how the stress impacts

our sleep and perhaps how we can try to

combat it and and to the point about

dreams do you find that stress also has

an impact on the types of dreams that we

have it does seem to have a relationship

and perhaps the best demonstration of

this is an extreme form of that which is

a condition called PTSD or

post-traumatic stress disorder where

people have incredibly difficult

traumatic experiences and stress and

what we commonly see there is a

consequence of repetitive nightmares

in fact it forms part of the diagnostic

criteria for you to receive a diagnosis

of PTSD so there is certainly some think

about our emotional waking life that

sort of bleeds over it’s almost the red

thread narrative that transitions into

our sleeping life and specifically our

dreaming life

and we do know however a study published

some years ago now demonstrating that if

people are dreaming are particularly

dreaming about some of those difficult

traumatic experiences it can actually be

beneficial that it leads to clinical

resolution of things such as depression

and trauma and bereavement so there is a

relationship between our waking life in

our Dreaming life when it comes to

emotional health and we do think that

sleep and particularly dream sleep plays

a form of a sort of mental health in

that regard and sort of dissipating and

removing some of that emotional stress

that definitely explains some of the

unusual dreams I’ve been having and I

imagine it’ll be helpful for some of our

viewers who have also been having odd

dreams so I’ll be back later with other