
Can genetics explain why some people thrive on less sleep? - bookofjoe
https://www.nytimes.com/2019/08/30/science/sleep-gene.html
======
stevesimmons
Answer is yes, definitely genetic. I have narcolepsy and need no more than 5
hours sleep a night. That has been proven consistently over the 28 years of my
working life.

I aim for 5 hours' sleep, though usually it's more like 4h45m. I am less sharp
once it falls below 4h30m. I usually work in the evenings til 12:30 or 1am. I
wake up around 5:20am, usually just before my alarm. I cycle to work and
arrive at the office shortly after 6am.

Narcolepsy is usually associated with daytime sleepiness. It is best described
as a switch in my brain that turns off if I don't get enough stimulation. I
was prescribed drugs for it (dexamphetamine originally, now modafinil) but I
don't take them anymore. I prefer to treat it by having very high-pressure
jobs (currently Chief Risk Officer for a start up, previously tech lead for an
investment bank trading desk). Also I have found that computer programming
provides the perfect amount of deep mental focus to beat narcolepsy.

At night, narcolepsy means I fall asleep instantly. I hit the REM sleep phase
within a couple of minutes. Most people need 90 minutes to reach REM sleep. So
that alone means 4h30m of my sleep is equivalent to 6 hours for a 'normal'
person.

(Final note: This was verified clinically by an overnight stay in a sleep lab
then daytime sleepiness tests the following day.)

~~~
rjkennedy98
Just because something is unique to you and persistent over a lifetime doesn't
make it genetic (there seems to be a huge lay misunderstanding about this). It
can also be epigenetic, which is basically the programmable layer on top of
your genome which causes certain genes to be expressed instead of others.

~~~
stevesimmons
It's definitely genetic in my case. My mum and two of her three siblings have
it, as did their grandmother. Family dinners often end with half the people
round the table falling asleep, and our spouses telling sleep-related
anecdotes.

------
diziet
Matthew Walker, professor of neuroscience and psychology at the University of
California, Berkeley focusing on sleep, would like to say something about
that:
[https://www.youtube.com/watch?v=5j9xCC_VtQA](https://www.youtube.com/watch?v=5j9xCC_VtQA)

Text writeups of similar talks:

[https://podcastnotes.org/2018/12/05/sleep-2/](https://podcastnotes.org/2018/12/05/sleep-2/)

[https://podcastnotes.org/2018/04/29/why-we-
sleep/](https://podcastnotes.org/2018/04/29/why-we-sleep/)

(Paraphrasing, but the percent of people who can get by on under 6 hours of
sleep rounded to a whole percent is 0)

~~~
JohnJamesRambo
Not disagreeing but doesn’t the second link you posted say five hours?

>Based on evidence from over 100,000 studies, the number of people who can
survive on 5 hours of sleep or less, without showing any impairment, rounded
to a whole number and expressed as a percentage of the population…is 0

------
yattias
According to Matthew Walker's book "Why we Sleep", sleep deprived people think
they thrive.
[https://inweb.notesalong.com/id/5d785df04818060013b15a78/htt...](https://inweb.notesalong.com/id/5d785df04818060013b15a78/https://www.theguardian.com/books/2017/sep/21/why-
we-sleep-by-matthew-walker-review#notesalong:5d785db5de43c60000733b2c;)

~~~
randomThoughts9
There are Yogis that claim they can thrive on 2.5 hours of sleep, and that
they've been doing that their entire life.

I don't think he addresses this subject in the book or in his talks, but it
would be interesting to know his opinion on the subject.

~~~
freyr
There are also yogis who claim they can levitate, read minds, or bring dead
babies back to life. Some healthy skepticism is in order.

[https://www.quora.com/Have-you-seen-Himalayan-yogis-who-
clai...](https://www.quora.com/Have-you-seen-Himalayan-yogis-who-claim-to-
have-supernatural-powers-Do-they-exist)

~~~
tofu325
_There are also yogis who claim they can levitate, read minds, or bring dead
babies back to life._

You don't need to be a yogi to do those things. There are men and women (even
kids and teenagers) who can read your mind like a page. Advanced ones can know
what you're thinking before you're even aware of what that thought is. And
they don't even have to be looking at you. It's 360 degree vision. Distance is
no barrier. People who can read minds know to respect your space, because they
know it's against spiritual law to violate your psychic space.

People who have developed the ability to bring the dead back to life will not
do it, because they know there's a reason why somebody had to die. Why mess
with the cycle of life?

~~~
SketchySeaBeast
> People who have developed the ability to bring the dead back to life will
> not do it, because they know there's a reason why somebody had to die.

That must be terribly reassuring to the families of car crash victims.

You can make all the extraordinary claims you want if you never have to prove
it, and no one should believe you until you do. You're basically just wasting
your breath and letting everyone know you believe in fairy tales.

~~~
tofu325
_That must be terribly reassuring to the families of car crash victims._

But maybe there's a reason why an automobile accident happened in the first
space. Live is not just made up of a series of random events.

~~~
SketchySeaBeast
> Live is not just made up of a series of random events.

 _citation needed_

You can make all the claims you want. Everything is being made as it goes
along, and if someone claims to have these powers and doesn't use them, they
are either lying, deluded, or terribly cruel. It's awfully convenient, and
really a sick joke, if the moment one has real agency, they can't use it.

------
Causality1
I've read several of these articles about genetics allowing some people to
feel well-rested on little sleep but a key factor always seems to be left out
of them: Are they actually well-rested? That is to say, how is their risk of
sleep deprivation-related illnesses such as heart disease, obesity, diabetes,
and depression? Is it as low as that of people who get a full night's rest or
do their genes simply mask the effects of sleep deprivation, making them feel
good while ravaging their physical health?

~~~
EliRivers
This article - [https://www.news-medical.net/news/20190828/UC-San-
Francisco-...](https://www.news-medical.net/news/20190828/UC-San-Francisco-
scientists-identify-second-short-sleep-gene-after-10-year-search.aspx) \-
touches on it.

The researcher mentions the typical effects of sleep deprivation - "This has
well-known, long-term health consequences. You're more likely to suffer from
cardiovascular disease, cancer, dementia, metabolic problems and a weakened
immune system." \- but says that these people don't suffer them.

This would suggest that they get all the sleep they need. They're just better
at sleeping than us so it doesn't take them as long to get enough.

As a less serious and more fun aside, I want to breed these people with that
group who have ridiculous endurance capability. The ultra-runners who only
stop because they fall asleep :) Like this feller;
[https://www.theguardian.com/lifeandstyle/the-running-
blog/20...](https://www.theguardian.com/lifeandstyle/the-running-
blog/2013/aug/30/dean-karnazes-man-run-forever)

~~~
Hitton
But it should be that most rare "benefical" mutations have at the same time
drawbacks, otherwise they would be probably much more widespread. In this case
the drawbacks are just not yet known.

~~~
SuoDuanDao
Or they used to have a drawback that is no longer relevant. I'm thinking for
instance that the world's longest continuous culture considers 'dreamtime' to
be more important in some ways than the waking world. It may be that the
functions which used to require 8 hours of sleep can be done during waking
hours as well, perhaps through greater caloric intake or more articulated
mythologizing.

------
robg
I’m surprised that the work on the glymphatic system still isn’t widely known,
but pretty clear it solves the why. We sleep because the glymphatic process
cleans the brain of the damage caused by waking life.

[https://www.ncbi.nlm.nih.gov/m/pubmed/25947369/](https://www.ncbi.nlm.nih.gov/m/pubmed/25947369/)

Seems likely the process is more efficient for some people versus others, just
as it’s active during waking life but much less so. Less/more
clearance/cleaning is mechanistically explained by the need for less/more
sleep.

------
harel
If I sleep 8 hours or more, I wake up like someone beat me up and I find I'm
tired and exhausted all day. 5-6 hours for me are the sweet spot (leaning
towards the 5). I'd love to know the reason because all "scientific"
literature always pushes me to take 8 hour sleeps. I always feel like I'm
doing something wrong going against "science" in that regard, but long sleeps
just don't work for me.

~~~
snikeris
When you don't sleep enough, your sympathetic nervous system (fight or flight)
gets activated. Your heart beats faster, cortisol is increased.

If you spend most of your time in this state it seems normal to you. A return
to good sleep might initially feel like you're stuck on a lower gear.

~~~
magashna
Unless brain fog is everyone's normal state, I disagree. 6.5-7 hours is my
optimal amount, if I sleep in and go 8+ I wake up in a haze and stay like that
much of the day.

~~~
d1zzy
I thought that's why most people drink coffee.

I optimally sleep ~9 hours every day and start to feel tired if I sleep less
for 3-4 consecutive days. I bike to work (and generally tend to go as hard as
I can, so heart rate tends to spend a lot of time in Z4 or so). I almost never
drink coffee so it takes me 2-3 hours to "fully awake" but I don't think
that's unnatural so I don't mind it, I let nature run its course.

------
gexla
Echoing a lot of other comments here. I can think I thrive on less than 8
hours of sleep, but I don't. I don't wake up to an alarm clock and feel rested
and all that. But the reason I don't need the alarm clock is because I use my
environment as an alarm clock. Once the combo of temperature and lighting hit
a certain sweet spot, I'm up. If I want to sleep longer, I go to bed earlier
so that the sweet spot is 8 hours out rather than 6 or less. If I allow
myself, my sleep requirements is 8 hours.

I'm glad I'm not "gifted" and I wouldn't want a magic pill or treatment which
would make me that way. We need 8 hours of sleep. If I'm smart enough, I can
figure out how to make my day with 8 hours of sleep. I'm not smart enough to
believe that getting by on less than 8 hours of sleep is a good thing
regardless of how I feel or what technology can do for me.

~~~
balfirevic
> and I wouldn't want a magic pill or treatment which would make me that way.
> We need 8 hours of sleep.

I mean, it's literally a magic pill that would make you not need 8 hours of
sleep.

------
crimsonalucard
I sleep about 6 hours or less. But this transition happened suddenly sometime
in my mid-twenties. I don't know if I'm suffering from insomnia or if I'm
still good.

Definitely do not feel as super rested as I use too.

~~~
jchw
I stopped having good rest at around 25, a year or so ago. Cause unknown as of
yet. I miss feeling well rested for sure.

~~~
pavel_lishin
I stopped having regular good night sleeps starting in February of 2016.

The reason is _definitely_ genetic, and started pre-k last week.

~~~
cgb223
As a younger guy who doesn’t have kids (yet) it’s crazy to me that parents can
thrive on 2-3 hours of sleep.

How do you do it?

Does it feel like you adapted? Or are you aware of a cognitive decline?

Like, what’s the experience like?

~~~
pavel_lishin
> _parents can thrive on 2-3 hours of sleep_

Oh, we didn't thrive. It sucked. There was absolutely a cognitive decline, and
physical exhaustion to boot. We adapted in the sense that we weren't falling
asleep on the subway after awhile, but I flat out told work not to expect my
best work for the next six months.

But it also wasn't 2-3 hours of sleep a night. Unless you get really unlucky,
babies do sleep for hours at a stretch; and you're very incentivized to sleep
when the baby sleeps.

There _are_ adaptive strategies! If you're supplementing with formula (or even
if you're not, to a lesser degree) you can take shifts. I would go to bed at
~9pm, and my wife would be "on call" until ~3am. After that, when the baby
woke up, I would be on call, and would wake up and take care of her until
~9am, when I had to leave for work. This guaranteed a six-hour period where
even though we'd get woken up, we could at least not have to get up and take
care of the kid. Granted, it's still interrupted sleep.

But in general, the experience is: you're happy but also low-key miserable,
and you feel like your head is full of cotton.

The low-level stress also impacts your immune system, so you get sick more,
and when your kid goes to daycare, you get sick _a lot more_.

~~~
oarabbus_
I think his question could be rephrased as "why don't we witness a mass
epidemic of parents falling asleep"?

I think many 20 and 30 somethings (without kids) who, if they were to get
under 6 or so hours of sleep for a couple nights, would automatically pass out
on the train/subway/bus/etc, in public.

So how are (seemingly most) parents getting 4 hours of sleep for extended
periods of time yet aren't falling asleep on public transit on their way to
work?

~~~
toast0
> So how are (seemingly most) parents getting 4 hours of sleep for extended
> periods of time yet aren't falling asleep on public transit on their way to
> work?

Most parents are getting more than 4 hours of sleep, but it's broken up. If
your kid is on a 3 hour feed/sleep cycle, and it takes 1 hour for feeding and
getting back to sleep (which is in the difficult part of the spectrum), that
leave s you 2 hours to sleep before another wake up.

If both parents are needed, or if it's a single parent, chances are you're
going to bed early, because you're exhausted; you'll probably go to bed when
the evening feeding is done, say at 9pm, sleep for two hours, wake up for 1
hour, go back to sleep at midnight for two more hours, wake up at 2 am to
feed, sleep again until 5 am, feed until 6 am and then get ready for the day.

You've ended up with 6 hours of sleep -- this is okish. If you have two
parents taking shifts, one parent slept from 9-11, and then from 12-5, for a
total of 7 hours; the other slept from 9-2, and from 3-5, also a total of 7
hours.

Of course, some nights don't go well, or the evening feeding is over at 8 and
you don't really want to go to bed then, and that pushes everything back. But,
if feeding only takes 30 minutes, that helps a bit. And some times the feeding
cycles clash with sleep cycles -- it was awful for the (thankfully short)
period where baby was consistently waking us up during REM sleep.

Also --- micronaps :D

~~~
journalctl
Just to be clear, six hours of broken sleep isn’t the same as six hours of
uninterrupted sleep. The longer you’re asleep, the deeper stages of sleep you
get to, which is important to being fully rested.

------
markus_zhang
Lucky guys. I wish I could need as little as 4 hours so that I have more free
time.

~~~
o10449366
As someone who does I promise you: no you don't

~~~
didibus
Why not?

~~~
himeexcelanta
Seems to me that having a physiological pattern which forces you outside the
normal rhythm of society could be detrimental to one’s mental health (pure
conjecture).

~~~
SomeOldThrow
Or beneficial! Depends on the context really.

------
nudq
Going on title and comments only, sorry, but why does "it's genetic" count as
an _explanation_ for anything?

An _explanation_ for this would need ecology. Why is it beneficial for some of
us to need less sleep, but not for all of us? What are the _trade-offs_? It
seems like needing less sleep has no downsides. Is it a novel, all-beneficial
mutation that just didn't have the time yet to sweep the population? Or do
short sleepers experience serious downsides?

There is no explanation in "we found a gene for it". Pretty much _every_
personality difference is genetic, that doesn't explain why such differences
evolved, or persist.

------
dragonelite
I'm fine and productive with 6 hours of sleep. I thought it was the coffee i
consumed that keeps my up, given how much we are told we need 8 hours or else
etc... So i decided to go without coffee for like 2 weeks. I didn't that much
feel different without coffee, less jittery. I like myself without coffee more
then with coffee. Right now i just use it as my pre workout and social event
with colleagues.

~~~
blaser-waffle
I'll second this. Caffeine is a reasonably powerful stimulant and most people
have a long term dependency on it.

Cutting down consumption and going to bed earlier definitely made a difference
to my mornings, and I've found I can usually swing less sleep. I often find
myself getting up at 4:30 or 5am, which isn't so bad in terms of free time--I
get a lot done at 5am.

------
speedplane
Given that so many people claim to thrive on less sleep, whereas so many other
people in the same gene pool make no such claim, there seems to be quite a bit
of evidence that nurture is far more at play here than nature. Not to say
genetics has no effect at all, but it seems pretty minimal.

------
Symmetry
This piece seems to be entirely about feelings of tiredness? That can be
important in some sorts of performance but what the other effects of sleep.
For instance, the quality of your NREM sleep _subsequent to_ learning new
vocabulary or REM sleep after learning new motor skills has a large effect on
how well the training takes. Do we have any evidence that people who feel the
need for less sleep, e.g., learn new languages as fast as people who get 8
hours a night or do they learn them as fast as people who get 6 hours a night
but use stimulants to prevent feelings of tiredness? I can actually imagine
mutations that give people faster sleep spindles or something but that's very
important for evaluating the impact of these sorts of genes.

------
jdlyga
I'm not sure if I'm totally fine on 6 hours of sleep, or I'm just so used to
it that I don't recognize the difference.

------
kazinator
Lugging small children in wheel carts intended for shopping, with no safety
harnesses, is ill-advised. What a poor photo to choose for the article.

------
laythea
This seems like a bit of a silly question seeing that nobody can actually know
the answer and therefore you will only get opinions.

------
renatoautore
Yes, there is a gene mutation that allows certain individuals to fully recover
after only 4 hours of sleep.

Lucky them I would say :)

~~~
oarabbus_
Source? As far as I know that's complete speculation. There is one single
study which followed one single family and implicated one gene which may
possibly allow people to be more alert on less sleep. Hardly scientific
consensus.

~~~
EliRivers
Two such genes have been independently identified, that I know of. There has
been more than one study.

Here's a piece from 2015; [http://www.bbc.com/future/story/20150706-the-woman-
who-barel...](http://www.bbc.com/future/story/20150706-the-woman-who-barely-
sleeps) , which discusses this from 2009 -
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2884988/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2884988/)

A search for studies on DEC2 suggests a steady stream of work going on;
[https://www.ncbi.nlm.nih.gov/pmc/?term=DEC2](https://www.ncbi.nlm.nih.gov/pmc/?term=DEC2)

Here's more recent research identifying another gene; [https://www.news-
medical.net/news/20190828/UC-San-Francisco-...](https://www.news-
medical.net/news/20190828/UC-San-Francisco-scientists-identify-second-short-
sleep-gene-after-10-year-search.aspx)

There has been more than one study, more than one family and more than one
gene implicated.

