
Do we really need eight hours of uninterrupted sleep a night? - selmat
https://www.weforum.org/agenda/2018/09/monday-s-medical-myth-you-need-eight-hours-of-continuous-sleep-each-night
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drej
I'm halfway through Matthew Walker's Why We Sleep. And it's terrifying. The
medical implications of insufficient sleep are rather worrisome.

[https://www.penguin.co.uk/books/295665/why-we-
sleep/97801419...](https://www.penguin.co.uk/books/295665/why-we-
sleep/9780141983769.html)

~~~
colechristensen
I read it, I liked it, I felt like it was not written very objectively.

There did not seem to be nearly enough self-doubt or testing alternate
situations.

And it shouldn't be terrifying. You no longer have to worry about animals
trying to eat you, finding enough food to eat yourself, dying of infection, or
physically defending yourself on a day to day basis.

If the worst thing that's wrong with you is sub-optimal sleep, you've got life
pretty good.

We're getting down to solving more and more subtle problems. Sleep, the
biological contents of your digestive system, and environmental exposures look
to be the big health problems on the table to solve in the next few decades.

~~~
manmal
Sub-optimal sleep can absolutely ruin you, in the long run. E.g. it's been
suggested that a significant portion (a third, IIRC, have to find that
article) of chronic fatigue incidents are due to non-restorative sleep.
Definitely a problem worth solving if you have it.

If you lie in bed awake once per week or so, you surely don't need to fret
about it. It just must not become part of your lifestyle - if it does, get a
checkup.

~~~
sbarker
Calm down. We all die in the long run... Want better sleep? Stop worrying and
work with your hands a bit.

~~~
marak830
Unfortunately that doesn't always work. Sometimes due to pure amounts of work
I have done over the day I just can't sleep when I get to bed. (Chef, so
definitely working with my hands haha)

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pqs
I work in Academia. I sleep after lunch every day. I have lunch in 30 minutes
and then I sleep 20 minutes. I have an sleeping mat and a pillow in my office
and I sleep on the floor. It really boosts my afternoon productivity,
specially now that I have a baby and wake up several times during the night.
During the weekends I sleep a little longer. I've been doing this for many
years and I struggle a little bit when in meetings and conferences, where I
can't sleep. But I'm learning to nap anywhere. ;-)

~~~
klausjensen
I wonder why it is, that some people can take a nap and feel refreshed. If I
do it, I wake up WAY more tired than before going to sleep and will be groggy
for a while.

I am guessing it must have something to do with how fast you can fall asleep
and enter deep sleep.

~~~
dest
The nap should be short, e.g. 30 min max.

~~~
thecatspaw
is that after falling asleep or including that time?

Im asking because I cant fall asleep in 30minutes

~~~
fouc
Generally 25 minutes of actual sleep.

If it takes you longer than 15 minutes to fall asleep, you might need to look
at cutting caffeine or other stimulants out of your diet completely. Exercise
will also help.

Usually helps if you're feeling a strong sleep inertia signal (i.e. desire to
sleep) compared to just feeling fatigued.

~~~
seba_dos1
I don't need caffeine or other stimulants for it to take me way more than 15
minutes...

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unhammer
It is important that people realize sleep cycles do exist, but this seems a
bit strawman-ish. If someone says "you need about 8 hours of uninterrupted
sleep" I would rather take that as meaning things like "don't get up after
just 5 hours" and "don't get up and check ebay auctions in the middle of the
night even if it just takes 10 minutes", not "don't panic if you naturally
wake up at 4am".

\-----

Btw, on

> Historical records also suggest that a segmented or bi-phasic sleep pattern
> was the norm before the industrial revolution.

there's an interesting comment at
[https://news.ycombinator.com/item?id=18051041](https://news.ycombinator.com/item?id=18051041)

~~~
jgtrosh
s/don't panic/panic/

~~~
unhammer
Doh! Thanks. That sentence got too complicated :)

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sgaduuw
Having become a dad for the first time 14 months ago had quite the impact on
the amount of uninterrupted sleep I have been getting since. I consider 4
hours in one stretch a good night. Averages are closer to 3 hours. My son
simply is not a good sleeper.

Even though my son brings a lot of fun to mine and my partner's life, I have
not felt well-rested since his birth, and feel impacted both mentally and
fysically due to that.

~~~
alimbada
I'm in the same boat. 3 years on and it's still extremely rare for my son not
to wake up multiple times through the night and have to spend at least 20 mins
(up to an hour or sometimes even up to 2 hours) getting him back to sleep.
We've just had our second child and our daughter at 2.5 months old is also not
a great sleeper during the night, but she will sleep through anything during
the day. Combine that with both the kids staggering their sleep/wake schedules
(as if they're colluding!) and I'm lucky to get a 3 hour stretch of sleep.
Since I've been back at work after paternity leave I've regularly caught
myself falling asleep at my desk at work and need to go and take a nap in my
car at lunch time just so I can function.

~~~
indemnity
Reading this while son has just woken up mid sleep cycle and decided to wake
the house... 10 month old :)

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AJRF
You can meditate, you can chug red bull or coffee, you can use pomodoro's or
live your life in a GTD system, but nothing will compare to the productivity
increase of getting a good nights sleep.

~~~
agumonkey
There's a catch 22, I always sleep deep when I had a full day prior :)

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bitL
I've tried multiple different sleep approaches in order to maximize "awake"
time, but defaulted back to exactly 8h/day - my body simply takes 8
uninterrupted hours and wakes me up precisely without any alarm clock. While
experimenting, I saw energy/cognitive decline (tested) after a while,
correcting when going back to 8h, so multi-phase sleep is definitely not for
me.

~~~
iamzozo
Same here. I got some energy from a mid-day/afternoon sleep, but after it also
takes an hour to wake up completely. Going below the 8 hour sleep in a row and
loosing focus. Even the weekends get messed up with less sleep.

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sshagent
At night i tend to get around 6 hours or so. I work from home and tend to find
a 90 minute nap, as my (long) lunch break really works well for me. I eat my
lunch whilst i work. This wouldn't work onsite, I'm sure, but it really works
well for me.

Gives me that little pick me up in the afternoon that i used to power through
with LOTS of coffee. Down to one coffee a day now

~~~
edoo
One coffee a day max is a good trick. Like all addictive substances there is a
seriously diminishing return and eventual swing patterns as tolerance builds.
One a day gives you the full effect and has a chance to fully leave your
system so you don't require coffee to function. Coffee withdrawal migraine
style headaches are a real thing.

~~~
sshagent
Took some major effort to get down to one, i suffered the horrid headaches as
you mentioned. It took a while to figure out what was causing it, it was me
not having any coffee.

Now my coffee machine glares at me each time in the kitchen, but just one in
the morning is all i do now :) I buy some lovely beans and just make sure that
ONE COFFEE IS GREAT!

------
neonate
This linked article by the same author is a bit better:
[https://theconversation.com/broken-sleep-its-a-
rollercoaster...](https://theconversation.com/broken-sleep-its-a-
rollercoaster-ride-1792).

~~~
ntock
What do you like more about the article you linked?

~~~
neonate
It seemed to me to have more information. They're pretty close though.

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anotheryou
I'm totally fine with splitting sleep in two, but it's incompatible with most
jobs and even social stuff.

It's hard to find a fixed 2,5h slot that can be blocked every day. I could
only do it during my high-school times.

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lcall
I personally know a case of trying the "uberman" sleep schedule (aka "da
vinci" sleep schedule, or ~30min sleep every four hours, permanently), having
tried hard but could never completely convert to the schedule, where doing so
is one of two strong possible causes of the individual now suffering very
debilitating Chronic Fatigue Syndrome and can no longer work regularly despite
years of medical tests and efforts.

~~~
brianwawok
That sounds like a terrible idea

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jason_slack
I sleep from 1am - 4am and then take 2 x 30 minute naps at 11am and 6pm. I've
done this for a very long time. As a child and teenager I was often forced to
try and sleep so I just lay awake. Once it was realized that I just couldn't
sleep I was allowed to do quiet tasks like read or after I learned to code,
code :-)

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stephengillie
My digestion won't support 8 hours of uninterrupted anything. I'm up 2-3 times
every night, as though I had a young child, but I'm single. Some nights, I'll
be up for an hour or more, then return to bed for "second sleep".

~~~
sleepysheep
I understand how difficult that can be.

I suffer from nocturia (diagnosed as non pathological after many rounds of
tests all turning up negative). In a typical night I get five hours max of
contiguous sleep and have started sleeping (by that I mean the in bed
duration) nine to ten hours as an attempt to compensate for not being able to
stay asleep.

I've always been curious about the difference between time spent in bed and
actual time in deep sleep and their equivalence (or exchange factor).

Have you also resulted in increasing how long you are in bed to compensate?

~~~
stephengillie
I've used Sleep for Android to track my sleeping patterns since about 2013. I
consistently get 3-4 hours of deep sleep per night in 6 hours of actual sleep.

Sometimes it's simpler to watch an hour of YouTube (or post on HN, upvotes are
easier at night), than to get up and lay back down several times.

The app pauses sleep tracking when it can tell you're awake. This makes it
annoying to see I've been sleeping from 9pm until 7am, and only got 6.5 hours
of sleep.

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edoo
I've experimented with two 3-4 hour sleep periods and it is great, two fresh
starts per day... but only works if you don't have anything resembling a
normal schedule.

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parski
On the subject of Why We Sleep: I'm not sure how well it corresponds to the
book, but Matthew Walker also has a Google Talks talk on the same subject that
I recommend watching if you're not a book person:

[https://www.youtube.com/watch?v=aXflBZXAucQ](https://www.youtube.com/watch?v=aXflBZXAucQ)

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bparsons
From a human performance and health point of view, yes, you need between 7-9
hrs of sleep a night.

It doesn't need to be continuous or perfect, but good sleep is going to have a
huge impact on your quality of life.

In the short term, you can deal with the less, but your cognitive function,
physical performance and metabolism are going to be impaired.

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j7ake
The amount of sleep also depends on age, obviously.

~~~
meijer
Well, kids need more, obviously.

But old people do not really less than young adults, according to "Why we
sleep".

~~~
coldtea
> _Well, kids need more, obviously._

Not really obvious. Babies and toddlers maybe, but kids after 5-6 seem to have
much more energy.

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Nursie
Meh. I don't really buy into this biphasic hype. If I go to sleep in the
afternoon, my body still wants several hours sleep and I'll wake up groggy,
disoriented and more tired than before.

I can live on 6, and feel bad. 8 is good. 9 is better. 10 is common for me at
weekends when I have no particular plans.

~~~
milpool
Absolutely the same here. And sometimes i wake up pretty early, feeling
totally awake. I find that in that case, I have to get up. If i force myself
to sleep 2 more hours, the day is basically ruined.

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m1k1
Of course, we don't. We need 9 !!!

