Ask HN: How much do you sleep at night? | Hacker News Reader

Ask HN: How much do you sleep at night?

28 pointshyperbovine65 comments

How many hours of sleep do you average a night? How do you feel it affects your work life, non-work life, and everything else?

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http://www.stanford.edu/~dement/sleepless.html

Stanford University Center of Excellence for the Diagnosis and Treatment of Sleep Disorders

Each of us has a specific daily sleep requirement. The average sleep requirement for college students is well over eight hours, and the majority of students would fall within the range of this value plus or minus one hour. If this amount is not obtained, a sleep debt is created. All lost sleep accumulates progressively as a larger and larger sleep indebtedness. Furthermore, your sleep debt does not go away or spontaneously decrease. The only way to reduce your individual sleep debt is by obtaining extra sleep over and above your daily requirement.

The powerful brain mechanism that regulates the daily amount of sleep is called the sleep homeostat. By increasing the tendency to fall asleep progressively in direct proportion to the increasing size of the sleep debt, this homeostatic process ensures that most people will get the amount of sleep they need, or close to it. The elevated sleep tendency together with the associated drowsiness and an intense desire for sleep would ordinarily prevent most people from becoming dangerously sleep deprived because they would go to bed early, or sleep late, when such excessive daytime sleepiness occurred.

However, in our society we are prone to ignore or resist nature's signal that we need more sleep, and we often resist far too long. At this point, we cannot resist falling asleep. Depending on when and where this happens, falling asleep can be tragic, or merely inconvenient. As far as is currently known, nothing can change an individual's fundamental daily sleep requirement.

"Does not go away" makes it sound permanent, but I read about an experiment to measure sleep debt that found it's sort of a decaying average over the last two weeks. There's no reason to think my body remembers exactly how many all-nighters I pulled in college.

Well, the idea is that you'll be tired enough that you'll almost always pay it back pretty promptly. So your body doesn't have to remember for a really long time because you don't keep a balance for that long.

For example, after you turned in the papers/took the exams from the all-nighters in college, you probably crashed and took a long nap or slept 12 hours that night or something.

It's not exact, obviously. I have found that you kinda get a "discount" when you get enough into sleep-debt. I slept about 15 hours over 6 nights once, and after basically sleeping for 24 hours straight, I was totally fine. So that was only like 16 hours of extra sleep (because 8 of the 24 have to count towards that night), which means with that the initial sleep + the paid back sleep was only ~31 hours for 6 nights, which is still only 5 hrs/night.

If you are not getting 7 to 8 hours, you are just fooling yourself into thinking you are a hero. You shall pay for those hours with your health.

Please post some studies showing how you get ill with less than this magical 7-8 hours sleep.

Say you sleep 2 hours less than "the norm". That means you get an extra 30 DAYS a year of 'awake' time. Over 50 years, that 2 hours has added up to an extra 4 years of useful awake time.

Would you rather have more time while you're young, and able to do stuff, or just live a bit longer when you're old and stuck in a home? (Assuming you're correct, and lack of sleep makes you die younger).

Everything in moderation - don't take things to extremes, but I'd say 5 hours is probably still healthy enough.

Having kids certainly helps with training yourself to not need much sleep.

It also depends on your level of activity. My sweet spot is 6-7 hours. I can function on 4-5 but it's a painful day and I end up making up for it on the next night. Anything more than 7 and I feel off kilter for the day.

umm btw... If you take good care of yourself I don't think it's likely you'll end up "stuck" in a home. I know plenty of older people who are vibrant and energetic.

Also, to me it makes intuitive sense that degeneration can be exponential. So a lil bit of carelessness all the time can accrue some major interest (ie. if you're outspending your body's budget on regeneration costs per day).

Right, but until I see some proof showing that 7-8 hours is the magic number humans need to get, I won't worry too much that I sleep less than that and still feel healthy.

I'm just curious, how much do you exercise during the week and (if so) how strenuous is it?

I go skating 2-3 times a week, about 3 hours a time. Probably most of my exercise...

Anecdotally it seems this depends a lot on the individual. Based on the actual studies I've read about (though I'll admit this is interpretation by science journalists rather than my reading the studies myself) this would generally be a very unproductive extra two hours, and would also cause a large chunk of the rest of your day to be less productive for mentally challenging tasks (the only kind I'm generally concerned about). That last point is why the kids argument doesn't seem to fly for me. When you have a baby that wakes you up every couple of hours, the tasks you are doing are routine, and man parents do it barely being conscious.

Kids aren't that routine - if only ;)

Oh damn now he's puked all over the laptop dammit. Eugh he has spots on his ear wonder if that's ok. Oh great now the nappy has exploded. Oh great now this bottle leaks.

But granted, some of it you can do semi conscious.

of course I meant most of the time. Of course they'll do things to jar you to full consciousness (good or bad). If they were that routine, who would want them?

A lot happens while your asleep. It's not just your brain repairing itself, although you'd think this would be important enough. In college, at the end of a few hours of study, I'd have some vague understanding of the material. After a full night of sleep, the next day, the information was sometimes clear as day.

Additionally, I'm convinced that your dreams, whether you remember them or not, influence your consciousness. That great idea you had may be a derivative of some really strange thoughts that went through your head while you were asleep.

The point is that sleeping isn't wasted time. There's really important things going on and the ones sleeping those 30 more days a year are probably going to get more out of their sleep than those staying awake for that time.

I agree. I often solve problems when asleep, and wake up with an answer. But picking any arbitrary number and saying people should sleep that much is a bad idea. One size doesn't fit all.

Definitely. The way I read his post, though, it was more to point out that you should get a full night of sleep and if you're bragging about only sleeping a few hours a night to be productive, you're not impressing anybody.

Fair enough... I wouldn't objected if he hadn't included the magic 7-8 hour figure. I agree, some people are sleeping too little trying to be a hero.

I found that with evening aerobic exercise (running, swimming) I naturally sleep less and awake as fresh or fresher than usual.

With exercise, 6-7 hours. Without, 7-8 hours.

I think that's pretty highly dependent on the individual. There's an article about the surgeon Charlie Wilson who slept around five and the half hours a night and yet excelled at his craft.

Article is at http://www.newyorker.com/archive/1999/08/02/1999_08_02_057_T...

You can search for the phrase "He goes to bed somewhere around eleven at night and rises at 4:30 A.M".

5 or 6 before getting laid off. 8 or 9 now and loving every minute of it. I can't tell you how much better I feel. I can take power naps on the couch and often solve the prolem I've been working on all morning, just after waking up. I work the entire day with breaks whenever I want and actually end up working 9 or more hours.

It's also great to work on my startup full time. My office is now the patio table if it's sunny or the back porch if it's raining. It's amazing how hard you'll "work" to not have to go back to "work".

There was a poll a while back: http://news.ycombinator.com/item?id=328901

Words to live by from George III:

"Six hours' sleep is enough for a man, seven for a woman and eight for a fool."

Of course, he was... well, mad.

The IDF foobar'd my sleep forever, or so I thought. When you're in the army the first few months is boot-camp -- they give you exactly six hours a day, that's including the time it takes for you to fall asleep. Teaches you submission or something along these lines.

Thing is, I really like sleeping. I love it.

So after a few years that this was done with, I tried to recover the joy I used to find in downtime. You know -- getting the rest, seeing the lucid dreams, waking up renewed and refreshed -- that sort of thing.

Turns out my "natural cycle" was permanently shortened by the way we were being worked, or so I feel. I can't go 18/6 or 16/8, and even 14/10 doesn't feel any more refreshing.

So I started doing 12/6. That's twelve hours to do what you've got to be doing and six to sleep, not including the time to fall asleep. If you stop consuming and producing information about an hour before you go to sleep you can fall asleep real fast, under 10 minutes.

The downside is that you'll have to be self-employed, or it won't work for you (sometimes your sleep will fall during the day).

Even if I feel it works for me, it does not necessarily mean you should do it. Try it for a week, and see.

About an hour less than I'd like to.

Through chronic undersleeping I've trained myself to undersleep, which leaves me groggy and vulnerable to minor colds and such. Some days I'm so tired I avoid talking to people because I know I sound mentally defective. Every once in a while this culminates in sleeping until noon, and having to call in sick and apologize to my boss.

I'm developing the discipline to avoid caffeine after 6pm and go to bed "early" (which right now means midnight or 1am) but sometimes it's just impossible to get enough sleep. Last night I set my alarm for 8:30 and went to bed at 1am, but I woke up at 7:30. Tired. ARRRGH! This happens more often than not. It looks like regaining my ability to sleep is going to require a long period of diet-level discipline. My recommendation to anyone who doesn't get enough sleep: fix your lifestyle before it becomes ingrained in your psychology and physiology.

If you want to sleep better, cut out caffeine after noon. It's got a much longer half-life than you think.

Also, rather than forcing yourself to try to sleep at a certain time, create consistency in when you wake up.

I did have to moderate my caffeine intake to avoid lying awake at night. I still drink several strong cups of coffee before noon, but after that I limit myself to three diet sodas. If I drink the last before 6pm, I don't have any problem going to sleep.

When I was younger I'd drink caffeine all day and then be too wired to sleep, but when I finally went to sleep, I'd sleep as long as I needed to. My biggest problem was that if I drank coffee I would stay up late and then sleep through my alarm in the morning. Now my problem is not sleeping long enough even when I have the chance.

Why not switch to decaf?

Mostly because I like caffeine. I've thought about kicking it entirely, but I hope that isn't necessary. Also, the decaf selection is pretty limited where I shop, and none of my favorite kinds of coffee are ever available as decaf. Usually the only light-roast decafs available are Central American coffees, which aren't my cup of tea, so to speak.

Personally on a normal week night I sleep for roughly 5 hours, and then on Saturdays and Sundays I usually sleep for 8-9 hours, so my overall average is around 6 hours a night.

I frequently wish I could sleep more and feel tired long before I go to bed most nights, but I do not take it to such an extreme that I believe it truly reduces my effectiveness. Of course, that is my subjective thought and I have not tried to precisely test it.

This describes me as well. I need those late night hours after the kids have gone to bed to code. I make it up on the weekend, but it's easy to get behind. Saturday and Sunday recovery sleep is sometimes interrupted, throwing the whole next week into a tailspin.

Sometimes, when I am way behind on rest, I go through a reset period. Normally this is marked by more sleeping hours and less interest in hacking... also less interest in social interaction.

Same here: 5 hours on a week, about 9 hours on weekends.

Also, sometimes I have a sleepy evenings. When I come home form work and fall asleep right after dinner. I sleep for about 5 or six hours, then wake up about 1 or 2 a.m., active for about 3 hours and take another 3-to-5-hours sleep before going to work. This happened to me yesterday.

It doesn't affect my productivity in any ways, although I really like when it happens.

I've having a particularly bad time right now (big and manifold responsibilities, not enough time) and only getting 3-5 hours / night on weeknights. This has been going on for months now (with some regular 7-8 hour sleeping nights once in a while).

Results I've found: Mornings really suck. I'm putting on weight. I also feel terribly unhealthy. I'm not as sharp as I am at full power (though this is subjective and very hard to discern). I can fall asleep in minutes if given a place to lay down. Also, I get sick much more often than usual (which was hardly at all). Subjective opinion: it feels like I'm prematurely aging myself.

Trying to "make up" the sleep on weekends doesn't work for me. Oversleeping just leads to bad headaches.

When I do get a solid 8 hours I feel like Superman the next day.

I'm hoping that I'm not doing any long-term damage to myself, but there's really no way out right now. :( The current job ends very soon (2 weeks!), and then I'll be able to resume normal sleeping habits (7-8 hrs/night).

Pretty much my experiences too. I had a couple of years burning my candle at both ends and I felt like what you described.

Now, if I stay up late I invariably get bad eye inflammation - you can set a clock to it. It has been diagnosed by several doctors as an auto-immune reaction caused by the immune system failing.

Neglect sleep and your body will let you know, probably before your good sense should have.

Ditto on putting on weight, ditto on the unpleasant effects of oversleeping to catch up, and ditto on not being sharp. The thing to keep in mind is that you're well beyond the point of diminishing returns. If you aren't achieving maximum output in somewhere between 6 and 10 working hours per day, then you're suffering from distractions -- something else is sucking up your productivity.

See my other post for my difficulty with undoing the habit of undersleeping. Even though I no longer experience any external pressure to undersleep, I still don't get enough sleep and suffer the consequences for it. It's hard to stop.

I get anywhere from 12+ to 5 hours of sleep, depending.

I'm 14 and I go to bed when I'm tired. I wake at 7:30 on weekdays for school and sleep for as long as I like on the weekends. The reason for my fluctuation of sleep is that I think most clearly during the night, which is when I get most of my hacking done. So I like living a night life when life is centered around the day and that screws up your sleeping.

There's nothing quite like being alone in a quiet house at 3 am in a room with nothing but a linux terminal.

Anyways, my sleeping habits don't affect my school learning(the days we actually learn stuff), nor my social life.

"You can't steal time from your sleep schedule, you can only borrow it. Eventually you have to pay it back. With interest. Yes, you have to get XYZ done by yesterday, or... or... Well, something really bad will happen. Take a minute to consider most deadlines you've had. Is the deliverable going to ship the day after the deadline? Of course not, this is just the regular monthly deliverable. By the time the shipping deliverable rolls around you'll be paying back your sleep debt, with interest. "

- bram cohen

The way I figure it is, some days you work harder and need more sleep, some days you need less. So I try to be like a machine: I'll wake up at 7am and go to sleep when I'm tired.

This results in me getting about 6-8 hours sleep a night - and no sleeping in on weekends! It throws my pattern completely out of whack.

As a previous poster said, the most productive hours for a hacker are the wee hours of the morning, when the wife/neightbours/kids piss off and let you code - but I think it's important to keep your waking hours as closely tied to sunrise/sunset as possible - it's all a compromise and one size doesn't fit all.

I've found recently that at crunch time on uni work/ freelance work I seem to just omit the having a life part of my day to maintain a similar amount of sleep.

Also the sleep moves from say midnight -1 to 10-11 to about 5-6 to 12-2

My sleeping pattern moves round the clock. Right now waking up around 5 pm. Wouldn't actually be much of a problem if there wouldn't be a society out there which prefers different sleeping patterns. I like coding at night (partly because it's rather noisy around here at day), but finding time for shopping can be difficult sometimes.

And I need 8-9 hours of sleep, anything below that and my productivity drops like a stone.

This is because researchers found out, that there are two tyes of persons regarding the "inner clock": for some the day lasts 23 hours for others 25 hours. Unless you regulate yourself with alarm-clock you will go cycles.

Between 6 and 7 hours on weeknights, probably between 8 and 9 on weekends. I don't think it's working for me that well, though. I usually go to sleep at midnight or 1, then get woken up by my alarm at 7:00, but snooze until 7:30 or 7:45 and it's really time to get going. I feel like it'd be a much better idea to just consistently go to sleep at 11 PM on weeknights, but I never really feel tired at that point. Also, I tend to stay up reading in bed.

Currently unemployed, so like 10.

Funny to see this post here today, as last day was actually one of those work-round-the-clock days (1h powernap), I usually try to aim for at least 6 hours. Less than that just makes me less efficient at work and I start skipping sports for the day ;). I usually have one day per week where I sleep really a lot, like 10 hours or so, which feels like it sort of recharges me for the week.

With spring/summer allergies I get really tired. I wish I could sleep an extra REM period. But I get 7 hours each night.

The theory that it is best to wake up during soft-sleeping between REM sleep interests me. As others have mentioned, sleeping too much can make you sleepy all day as well.

Anyone got one of those alarm clocks that wake you up when you sleep softly between REMs?

6-7. I don't use an alarm clock, but that's the amount of time my body feels like it needs. When I'm under a crunch, it will sometimes drop to 5, but I don't do that for very long. I regularly only got about 4 hours / night during college and I'm sure it negatively impacted my grades.

Usually 6.5 - 7

Get up, go to the gym, nice cool morning air after the gym and shower, and to work before everyone gets in.

When I was a student, I used to go to bed at 7:00-8:00 and wake up at 12:00-13:00, so that's about 5 hours. When saturday came, I visited my parents, went to bed at 12:00, saturday noon and woke up at 16:00, sunday afternoon. I really miss those days.

Sounds about the same as me for my first two semesters. Only difference is instead of going home on the weekends I would take an hour nap before my early Friday class then go back to sleep until Saturday after the class was over. Glad I'm not doing that anymore :)

Off topic: Are you the kaitnieks that created Autorune and SCAR?

5-6 hours during the night, if the kids are sleeping well. If I have to get up in the night, I often take a 20-45 min nap the next afternoon. Even if no child wakes me up, I virtually never sleep more than 8 hours.

I think it's also important not only how many hours, but when. If you have a daily work, well you must sleep at night. But if you are a Freelancer for example? Do you sleep at 3am? 6am? 10am?

About 5 hours. I fall asleep at ~2, I get up at 7 to get the kids to school. I sleep in on Saturday and doze Sunday morning until the kids force me to make the weekly pancakes at around 11a.

I go to sleep between 1 to 2AM and get to my computer about 10-10:30AM. But I usually lay in bed for a little while as I regain consciousness.

Around 9. But just a number doesn't say enough by far. I've been through about one year with only 7 hours and have been perfectly fine - I used to wake up by myself because I had something exciting to do. Most of the time though waking up an hour earlier will cost me a full day of drowsiness.

Also this, about 2-3 hours. But freelancing, so it's ok. http://en.wikipedia.org/wiki/Delayed_sleep_phase_syndrome

7-8, tend to feel better when I sleep 7 instead of 8 btw. Btw I get this sleep in a strange range... from 02:00am to 10:00am

I'm the same way. If I sleep 8 hours I'm wiped out for most of the day.

Five or six hours nightly during the week, generally some more on the weekends. Pretty typical for 22 years old I'd assume.

10 hours. I like down-time.

8-9

6 with occasional 10 minute naps in the office chair.

Lately, not enough but usually at least 7 hours.

Who sleeps at night?

As far as I am informed, the amount of sleep one needs varies from person to person. I am no expert but I did read some stuff about it. Also on the whole there is not done that much research about sleep.

I did test it out for myself. Without caffeine-intake my body regulates to a 7,5 hours sleep patern, no alarm-clock needed. With caffeine (2 cups of coffee + a tea) and alcohol (2 beers or so) intake I need ~10 hours sleep per night.

As much as necessary, and no hour longer.

It's not hours that count, but quality. You have to prepare your sleep time, really shutting down as much as possible.

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