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look at this it's a recent research
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paper on sleep and although it doesn't
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seem like it buried in these pages is a
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profound Discovery a discovery that
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surprised the doctors doing the research
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a discovery that challenges widely held
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beliefs about sleep and one that could
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have a massive effect on your life and
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life expectancy if you've ever wondered
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if there's a simple way to feel less
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tired all the time or boost your brain
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power or how sleep affects your
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wellbeing the answers are here and today
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we're going to explore them
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if you go long enough without sleep
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you'll die but why the answer to that
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question is something that doctors and
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scientists are only just beginning to
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figure out but philosophers well they
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were thinking about it thousands of
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years ago come with me back in time
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because our relationship with sleep has
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a fascinating
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history and but
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again it's the 4th Century BC the agnc
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glimmers under the Moonlight while
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Lamplight flickers in the homes of
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philosophers like El Mayon and arist
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Al B suggests that sleep occurs when
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blood Retreats from the body into the
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brain go me which as you'll see is
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insightful but it's Aristotle's ideas
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about sleep which are remarkable and
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resonate through the centuries we'll
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come back to him in the Middle Ages a
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time not known for its scientific
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Insight nightmares are considered
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evidence of demonic possession some of
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the ideas around sleep well they're very
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different from ours stay at an inn in
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the Middle Ages and you can't expect to
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sleep alone because communal sleep sing
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is the convention there might be one two
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or three other people in your bed
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families all sleep in the same bed with
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extended family members servants guests
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and even strangers privacy is just not a
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concept now obviously I can't go back to
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the Middle Ages to show you what it was
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like so I've come to Newcastle in the
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north where in places like this they
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still sleep 15 to a bed why scientists
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just don't
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know I want to find out so I'm going to
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ask some
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locals so what does any of this have to
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do with this study and how can it help
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you well although medieval people were
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uninformed about most things compared to
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us and had some very unusual Customs
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like trying animals for breaking the
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law guilty
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they did get some things right about
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sleeping because they cared more about
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sleep than you they went to bed at
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Sunset woke up for an hour at midnight
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this was called The Watch went back to
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sleep and woke up at dawn ready for the
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day it's called B phasic sleep and was a
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popular sleeping practice dating back
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thousands of years Aristotle wrote about
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it and it went way back Beyond him as
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well to the ancient Egyptians so by the
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Middle Ages we had sleep completely
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sorted but then something came along and
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ruined our relationship with sleep
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actually it was two things nothing last
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Is
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it artificial light was one thing the
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other the Industrial
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Revolution instead of working on a farm
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artificial light and factory work meant
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that a worker would now start at about
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5:30 a.m. work until 9:00 p.m. maybe
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lose a couple of Limbs during the day
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and sleep for 5 to 6 hours ready to go
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again the next day at least I get
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weekends off 7 days a week
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oh so the Industrial Revolution changed
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work patterns shortening sleep time and
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making it less flexible but it did
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something else too it changed social
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attitudes towards sleep instead of
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valuing it we considered it an
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unproductive waste of time idiots we put
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through a policy of purchasing Council
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houses by their tenants of here someone
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that was famous for sleeping just 4
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hours a night oh and some other things
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but that's what people aspy to to get by
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on as little sleep as possible so the
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attitudes from the Industrial Revolution
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infected the entire 20th centures ideas
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about sleep and they still have an
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influence now so if you have difficulty
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sleeping you can blame the Industrial
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Revolution obviously your phone TV and
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video game addiction doesn't help you
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should probably eat more healthily and
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get more exercise and practice sleep
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hygiene but you can blame the Industrial
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Revolution
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[Music]
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do you get enough too little too much
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scientists used to think that sleep
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duration was the most important
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indicator of sleep Health which isn't
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much use if you have problem sleeping
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for me worrying about getting enough
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sleep just causes sleep anxiety you
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can't control it but this study shows
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there's something more important than
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duration which you can control
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incidentally 6 to 8 hours is considered
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the optimal time sleeping so what is it
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what did this study find you remember
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those medieval people that like sharing
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beds it was something that they
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naturally built into their lives I don't
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know if you think back to what their
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lives were like whether that gives you a
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clue as to what it might be and and it's
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not bed sharing that's not it and it's
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so simple and yet Studies have shown
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that it can improve cardiovascular
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health what else metabolic function
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mental and cognitive function immune
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function and overall health and I'm
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going to tell you what it is in a second
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but I'm wonder that it's going to be an
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anticlimax because it's such a simple
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thing to do so here it is here is what
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the study
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found it's sleep regularity basically
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all you have to do is go to bed at the
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same time every night including weekends
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and that's the key and that's where it
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can get difficult because as well as
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work disrupting your sleep patterns
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thank you Industrial Revolution most
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people in industrial countries suffer
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from from something called social jet
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lag which is where your biological clock
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doesn't align with your social schedule
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basically you stay out too late at
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weekends stop doing that and you can
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reap these health benefits that's what
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the study says I want to show you
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something that's quite terrifying just
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hold on a sec it's just over there I
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just need to get it
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sorry here it is now it might not look
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terrifying but there it is why we sleep
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by Matthew Walker this was WR in 2017 it
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sold lots of copies but if you haven't
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read it and you're remotely interested
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in sleep and let's face it if you've
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made it this far through the video then
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you must be then I suggest you read it
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but it is a frightening read because it
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spends a lot of time explaining the
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dangers of not sleeping and they are
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quite ghastly so if you want to know why
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we sleep the importance of sleep the
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dangers of not getting enough sleep what
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happens when you're asleep how sleep
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helps to rejuvenate the body then I
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definitely recommend reading this book
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I've put a link in the description I
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think you'll like so why do we get tired
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what happens in our bodies when we're
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asleep and and why is that good for us I
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know a little bit about that now cuz
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I've read this book keep watching and
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I'll show
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you it's 9:00 p.m. you've been awake
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since 7:00 a.m. and you're beginning to
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feel tired why there are two main
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reasons the first are your Cadian
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rhythms these are part of your body's
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internal clock what affects them
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external environmental factors
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particularly light it's getting dark
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outside melat starts flooding through
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your body and whilst it doesn't make you
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sleepy it puts you in a state of quiet
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wakefulness it's preparing you for sleep
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but that's not why you're feeling tired
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at 9:00 p.m. your body has a second
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system and it's active all the time and
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it gradually builds up sleep pressure
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throughout the day it's called sleep
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wake
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homeostasis or is it homeostasis as you
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go through the day adenosine is building
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up in your brain and it's that that
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makes you tired you're so tired you
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can't make it through what you're
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watching on Netflix it's rubbish anyway
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so you drag yourself off to bed and fall
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asleep you might be resting now but
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inside your brain things are just
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getting going all the adenosine that
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built up during the day that's getting
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cleared away cerebros spinal fluid
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washes in and clears out other metabolic
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waste which accumulates throughout the
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day like beta ameloid plaques which is a
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good thing because they're associated
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with Alzheimer's disease and there's a
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lot more about to happen in your brain
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as you lie there covered in your own
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drawer your body is carrying out
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essential maintenance on your brain it's
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regulated by the lymphatic system which
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is like the Waste Management Department
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of your brain and as it gets to work the
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space between your brain cells expands
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to allow for better cleaning access
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after a full day firing your synapses
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synapses synapses are being returned to
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their normal State your brain's thinking
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system is being reset crucial for
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neuroplasticity and the ability to learn
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new things slow wave sleep is allowing
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the brain to process and retain new
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information learned during the day and
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you thought you were resting outside the
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brain growth hormone is being released
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for tissue repair the cardiovascular
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systems being rested the endocrine and
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metabolic system supported and repairs
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are carried out to the respiratory
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system getting sleep bright can boost
00:09:23
your brain power and something else that
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