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.)
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.
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.
Basically sleep, or lack of sleep, does not affect my recovery from sport.
My ideal work/life balance includes 12 hours' work and 3 hours' sport a day. I'd vary sports rather than have a day off.
For 4 years, when I lived in Melbourne, Australia, my usual weekday routine was:
* Up by 5:30am. Marathon kayaking from 6am to 7am. Cycle to work. Start work at 8am.
* Work til 7pm. Cycle to swim, water polo, or gym (which I did together with my partner). Cycle home.
* Dinner with my partner from 9 to 10:30pm. Work or recreational programming til midnight.
At weekends, I'd try to fit in a 2-3 hour run or marathon kayaking training. My narcolepsy would be much worse after long training sessions (due I think to dehydration and elevated core body temperature) and I'd often fall asleep, sometimes on the floor, for an hour or two.
Over the last few years, now I live in London, I've dropped water polo and am focussing more on flamenco dancing. If work is not too busy, I'll manage to do 2-3 three hour classes a week. If I have time on Saturdays, I'll do 5-6 hours of sport: cycling/kayaking/cycling/water polo/swimming, or flamenco/flamenco/streetdance/streetdance, etc.
Basically, my work/sport/sleep routine is not normal. It works perfectly for me. I definitely don't recommend it to anyone else.
This type of behavior has been rewarded throughout history. Spending insane amounts of time and energy on things nobody else could dedicate the time to is what made Michaelangelo, Edison, Tesla, Newton, the legends that they are.
I’m somewhat similar, but I never feel sleepy even if i spend 24 or more hours awake, i will feel extremely tired but never like some people falling asleep in their desk or while driving, i need to intentionally go to sleep and it will be instant, 6hs is my optimal sleep time and most of my family from my mother side is the same.
Modafinil is so really powerful stuff. It took me a second to realize you said you no longer take it. The whole time I was thinking of course you don't sleep, modafinil can make anyone survive on very little sleep for an extended period of time.
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
I disagree. A well-rested mind is almost categorically different than a 5-hour-a-night mind. It doesn't matter how hard you work if you're unable to have the insight that the thing you're working on doesn't matter or you need to make some other strategic change.
Optimal or not there are plenty of people in society who are doing just fine on <6hr of sleep every night.
The results kind of speak for themselves. These people have jobs, families and generally productive lives like everyone else. If these people felt the extra sleep made their lives better than the extra time to do stuff they'd probably sleep more.
Yes, but they are deficient in many aspects without realizing it. For example, Alzheimers is almost certainly a condition caused by chronic sleep deprivation. The results don't speak for themselves at all. Read Matthew Walkers book and you'll have a better understanding of why we need 8 hours of sleep, and anyone saying otherwise is frankly misinformed.
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?
> 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.
> Live is not just made up of a series of random events.
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.
>There are Yogis that claim they can thrive on 2.5 hours of sleep, and that they've been doing that their entire life.
Yes, and tons of people fall for that. They're up there with those other yogis who "don't eat food" (e.g. "Prahlad Jani is an Indian breatharian monk who claims to have lived without food and water since 1940"), perform magical tasks, and so on...
I started meditating 9 years ago and do yoga once a week and am pretty sure that if I made a lifestyle out of it i could reduce sleep need however I suspect the hours of sleep I gain will be used to meditate so in the end you don't gain that much in terms of free time per day.
You might be more productive per minute after meditating but that's another discussion
I do agree with you, whenever I meditate more often I sleep less. Also, I end up "gaining" time because I pay less attention to distractions/time wasters/procrastination.
However, in my experience it takes years before you may comfortably spend all day meditating. I'm pretty sure most of meditators, teachers or otherwise, are not able to do this. It's extremely demanding, it is only boring if you don't focus properly.
I've participated in retreats that start at 2h30AM and end at 00H00 every day, with 1h sits and 20m breaks in between (same routine over 3-7 weeks), and only a handful of people are able to follow this schedule. Even meditation "only" on a 9-5 schedule is hard.
My original reply was hyperbole. I did not mean they literally meditate all day. I meant that a day in the life of a yogi is very different than that of a normal person let alone a western one so their required sleep time is irrelevant to the discussion
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?
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.
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.
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.
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.
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.
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.
It's not low-gear though. I feel bad after 8 hours. Not refreshed, stiff to a point of pain, hard to focus and so so tired like i haven't slept for days. If I manage 5 hours I wake up refreshed and stay like that most of the day. I don't particularly like the whole "quota" system. I want to sleep as much as I sleep without thinking about it too much. Most times my body will just wake up by itself after about 5 hours anyway, before any alarms ring but sometime it doesn't.
> Most times my body will just wake up by itself after about 5 hours anyway, before any alarms ring but sometime it doesn't.
I was there about a year ago. I'm still working on it, but things are improved. The last hours of sleep are heavy on REM sleep, and I tend to get a bit restless during this time. In the past I would just get up and start my day. However, REM sleep is important, and it's worth working towards improving here. Seems like you're a little concerned you're not heeding the scientific consensus. Check out Dr. Walker's book, so you can be more sure of your current state or more informed. The time spent reading the book might produce 10 years more lifespan.
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.
I used to need over 9 hours of sleep, preferably 10. Now in my late 20s I make do with 7-8 hours with some impact on mental sharpness and likely physical health as well but otherwise able to function. Does wonders for my work life balance since I actually have time in the evening for hobbies / activities / relaxing.
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.
> 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.
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.
> So how are (seemingly most) parents getting 4 hours of sleep for extended periods of time
If this is happening and you're not a single parent and your kid's not got chronic health issues, you're doing something wrong. And actually unless both those things are true you should still be able to manage 6-9hrs (though with one or two interruptions, admittedly). Most parents do not manage to screw themselves this badly for very long before figuring out what's up, I'm sure, because the solutions aren't exactly rocket science (take shifts to ensure 5-6hrs uninterrupted plus more with interruptions for both partners; go to bed earlier)
As someone with a six month old, there is no thriving. I was a zombie for the 4 months or so, and we’re lucky. Our baby started sleeping through the night at three months.
My sleep has not recovered, and I don’t expect it will for a few years. On the other hand, I’m not going out drinking anymore, or staying out late, so all those hangovers mornings I used to have don’t happen anymore, and I think that just cancels out the sleep deprivation.
Your sleep schedule will get better, based on my experience, as the kid begins to sleep through the night. (Though they naturally revert back to staggered sleep from time to time as they develop, so good luck!)
And yeah - I significantly cut down on my drinking for awhile, because while waking up with a hangover is never fun, waking up with a hangover and having to take care of a small child is awful.
I got used to sleeping much less after having a kid. It varies by parent and kid but, for me:
It was really bad early on with the overnight feeding --- this was a two person endeavor for several months until we gave up on milk coming in and just did formula. As the kid got older, the cycle lengthened. Initially we got about 2 hours of sleep after feeding before he woke us up, this was actually better than when it got to three hours, and we'd wake up in the middle of a rem cycle every time. Once it got to 4 hours sleep every time, it was fine enough. I have a much harder time remembering things from this period of my life than before or after; I suspect as a consequence of persistent sleep deprivation. I also accidentally found out what happens when I stay up for 24 hours straight, I don't care for that.
I still don't get as much sleep as pre-kid, 8 years later, but I've adapted. One nice thing is I would say I may have trouble falling asleep once or twice a year now, instead of once or twice a month. I'm looking forward to 5th grade when his school district pushes back the start time, so I can wake up later.
The first three to four months is hard because the baby eats sleep every two hours, cycle gets longer as they aged. I suffered vertigo on the fourth month because i moved my head rapidly left to right. You will try to adapt but your body will suffer.
Our child was pretty good at sleeping overnight, barring a few frustrating weeks.
Mostly we found it fair to divide the night into half for her, and half for me; if he woke up between bedtime and 1AM my wife would deal with him. If he woke between 1AM and morning I would deal with him.
Having two hours of sleep total? That would kill me. But waking up for a few minutes, then going back to bed a couple of times in one night? Not as bad as you'd think. I know I zombie-walked a few mornings, but it didn't seem to cause too many actual problems. Of course when we were in this phase we'd often try to go to bed ourselves as early as possible.
2-3 hrs is too less, as a father of 2 we used to get woken up 2-3 times a night, over an 8 hour period. More so with my older one who had colic, and it continued for a year. She breast fed while I changed diapers. You get very good at going back right to sleep. I remember I got eczema because of the stress ( under my eyes ). Looked like a racoon!
Evolution has prepared women's bodies to thrive on little sleep after childbirth.
I have a coworker with a newborn. She falls asleep at her desk sometimes. I totally get it, and I feel for her, but I don’t think it’s correct that women thrive on little sleep after childbirth. The truth is: nobody thrives on little sleep. Humans need sleep. It isn’t entirely clear why, but we do, and the effects of sleep deprivation have been studied. Cognitive function declines, disease risk goes up, and in the worst case you start falling asleep at inopportune times, like while driving.
Working women should be allowed to take a year off paid, with the assurance that they can return to their job.
California allows 12 weeks maternity leave and upto 6 months wherein you can return to the job. Some states have no job protection ( how does that even work in a first world country?)
I started feeling tired all the time despite getting eight to nine hours of sleep a night. I was afraid it might be a thyroid thing but a blood test showed I had low iron. This was not expected as I'm a guy, but the doctor suspected it had something to do with weightlifting. I was put on an iron supplement and started feeling better.
So you might want to visit a doctor and get checked out if you haven't already.
So I had a live-in tenant with this ability. Getting woken up an hour after I went to bed and then again an hour before my alarm by the normal activities of an awake person took its toll on my health and we had to part ways. I had lived with many people before that.
I do, and I still wish for more than 24 hours to a day, because of how much work I need to get done every day. I typically get 3-4 hours, with the sweet spot at about 3.5 hours. And I've been doing that since I was about 14. Sometimes I sleep for 6 hours, but that's very rare. Sleeping for 8 hours is out of the question, because there's no way my eyes will remain closed for that long. And I've only used an alarm once, back when I was in high school.
Once I wake up, that's it, until it's time to call it a day again. And I don't drink coffee or take any other stimulant. I only get tired or fall asleep during the day if I eat something that has a high Glycemic Index or too much of something that has a high Glycemic Load.
I mean as long as you can keep healthy as the guys in that article, why not?
I can already imagine the beautiful life I'm going to have if I only need to sleep 4-5 hours. Getting up at 4:30AM, brew some coffee and make breakfast, sit down at 5:00AM and code for like 3 hours. Then I'd workout a bit, take a shower and go to work.
My job is pretty demanding at the moment so I'd rather do the more interesting stuffs in the morning instead of after work (I usually arrive at home around 7pm so it's a bit tough).
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.
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.
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.
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.
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.
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.