Hacker News new | past | comments | ask | show | jobs | submit login
Not everyone needs 8 hours of sleep: new research (time.com)
195 points by laurex 8 months ago | hide | past | favorite | 177 comments

It seems the problem is not that _everyone_ needs a full 8, but that many people _assume_ they don’t need that much, even though they do.

I don’t sleep 8 every night: sometimes it’s longer, usually it’s more like 6, but either way I don’t use an alarm to wake up.

The key for me was to prioritize my sleep health by minimizing screen time before bed, going to bed consistently at the same time, and always leaving enough time to get 8 full hours if my body ends up wanting it.

I don’t _always_ need 8 hours, but it makes a huge difference when I do. And empirically, my well being—physical and mental—improves substantially if I am going out of my way to tend my sleep health.

I feel that most people would benefit from knowing more about how to get a good night's sleep, but have a hard time figuring out what to do exactly.

So this thread helps but also something like this article about sleep hacking is very helpful: https://medium.com/better-humans/what-i-learned-from-six-mon...

I recently experimented with bed linen made by bamboo, but did not experience any big effect. Bamboo is supposed to regulate the temperature at night, but didn't seem able to on warm summer nights.

> I feel that most people would benefit from knowing more about how to get a good night's sleep, but have a hard time figuring out what to do exactly.

I personally don't agree. For pretty much all the people I know who won't sleep enough (that is, most of the people I known), it falls into the more general problem of health hygiene denial:

  - knowing that one should sleep more, but for <any reason> one doesn't,
  - having anxiety problems (eg. waking up early and not falling back asleep due to "mind rush").
While the second is certainly a serious problem that needs a medical (in a broad sense) approach, I'm very skeptical about dealing effectively with the first.

The negative effects of eating junk and smoking are extremely well known, and still, there's a large amount of people who do it.

Sleep deprivation on the other hand has obvious negative effects, buy they're not documented/perceived, in common culture, as being catastrophic (eg. you risk to die); it has also the perception of being a time waste, which conflicts with the busy requirements of a modern life.

Call me pessimistic, but I can hardly see a way to realistically (I stress "reastically") improve the situation on large scale (like smoke campaigns decrease smokers).

You may be on to something with the smoke campaigns. Maybe there could be some campaigning directly for sleep quality.

For example, I sometimes smoke "socially", sometimes up to half a pack during a night out. I never perceived it as "catastrophic", just as you say people don't perceive not sleeping enough as catastrophic. I would bet a lot of people don't feel like dying after smoking a cigarette or ten. The point is that maybe those campaigns do work, even when the issue isn't perceived as "critical" by the people. It could be launched as an education campaign, for the long haul.

Another thing which helped me a lot with sleep quality is exercise. And this is something for which there already are campaigns, at least in France, and from what I see it becomes more and more common to see people advocating for it. However, I don't see those campaigns talk about the effect of exercise on sleep.

When I started lifting some weights (nothing much, just a bunch of dumbbell exercises in my apartment) and going for short, light runs (around 30 minutes around my neighborhood) I noticed my sleep quality had improved enormously. A few weeks in, I actually started to sleep less than before. Went from around 7-8 hours and having a hard time waking up to around 6 hours and waking up refreshed and without an alarm.

So what I found out was that exercise actually turned out to be "free" from a time standpoint. But the overall levels of energy during the day went through the roof. Of course, the first two to three weeks were hard, especially waking up in the morning, but it was worth it.

Don't underestimate smoking, especially it must be avoided at all costs as a programmer. The minute you stumble on a problem which happens all day in the life of a programmer, the brain cues to smoke which actually causes digestive problem leading to constipation and sleep deprivation. Occasional smoking is a joke. Take a look at other profession and you can see smokers have an amazing career such as movies. I have not found a single programmer who has rose to the top of the field while still being a smoker.

I've found sleep hygiene is a big part of it for me. If I'm on a screen all day and night, right up until bed, I will need 8-9 hours to feel well rested. If I'm screen-free for 2-3 hours before bed, after a night or two I am as rested on 7 hours. And this maintains for as long as I'm good about being screen-free (Kindle included but that's just me perhaps, or psychosomatic maybe). Unfortunately it's not always possible to be away from all screens for that long at the right time, and it seems pretty easy to mess it up for several days with one or two slip ups.

I wish I could sleep eight hours but I tend to get up regardless at the same time alarm or not. I do try to enforce an afternoon nap or just eyes closed time.

I know nothing about the viability but like others you just find what works for you. I do know when I don't have enough sleep, it is really easy - I am irritable

Same here, even if I fall asleep as late as like 2am (which is rare) I tend to wake up a little after 6am now.

I do have a sleep apnea issue so that might have something to do with it but I think I'm currently sleeping in a way that it's not bothering me as much, in a recliner (at some point I need to get the machine but I can't get the titration right now because pandemic).

There's just something about 6am (the light? my dogs wanting to go outside?) that gets me every time.

Didn't used to be the case when I was younger. I could sleep 10+ hours easy. Now I'm lucky to get more than 7 usually, and usually only about 6 hours.

Anyone who isn't using flux[0] after 8pm is seriously hurting themselves. Once you use it, you can't go back.

[0] https://justgetflux.com/

Well recent studies show that software like flux only does a little and maybe even nothing to help you sleep better.

The problem is that we keep our brains active late at night and that's the reason why it is hard to get to sleep.

For me alcohol is the one that messes with my sleep. The lack of deep sleep makes me feel tired the next day(s).

Edit: an article about recent studies: https://time.com/5752454/blue-light-sleep/

Can confirm sibling's observation.

I find it much easier to fall asleep when the light is redder. Even for example when reading a book, if there's a lot of bright light in the room I will have a much harder time falling asleep.

I've noticed that if I wake up for some reason at night and turn the lights on, if the light is bluer it will tend to wake me up completely, whereas a red light will allow me to stay "sleepy" and fall back asleep quicker.

> The problem is that we keep our brains active late at night and that's the reason why it is hard to get to sleep.

You are correct, however, that's a confounding problem. The (relatively) weak effectiveness of software solutions is due to blocking only a small percentage of blue light from a (relatively) strong light source (assumes short distance to screen, low ambient light at night).

Blue light (and even some green light frequencies) is a hardwired stimulus feeding into your circadian rhythm. Blocking all blue and green frequencies, e.g. with simple welding glasses, is effective in supporting the creation of melatonin.

But again, having enough melatonin in your system is a necessary but not sufficient condition to be able to sleep.

Maybe it's placebo, but after installing flux I fall asleep at 22:00-23:00. Before I often stayed up till 01:00.

I still read a lot on computer in the evening, but I get sleepy much earlier.

if anyone is interested, Michael from f.lux provided some great info in relation to the study the Time article is referencing when it was originally posted on HN:


Or the blue light-removing features that are built into most modern OS - Windows 10 has it ('Night Light'), Android ('Night Mode') and IoS ('Night Shift') have it.

Flux was great but for the most part modern OS' have caught up and it's no longer needed.

'In 2009 we first approached Apple to get f.lux on iPhones. Years of promises of API access. The last conversation we had with them was "that's too weird for most of our users. Like the Klingon keyboard." Then, they announced their clone onstage, Macworld 2016.'


This is just Apple. It's useless, implausible, unreasonable, unviable...

Right up until other people do all the R&D for them so they can pick out the parts they like for a big announcement on stage. It's a smart strategy. They get to look like geniuses while others do the hard work and take all the risk.

They just went on with the times, 2016 was the year when everyone was obsessed about the "blue light disrupts your sleep" theories. Android, Windows and macOS were all on-board.

It's very likely that the team that said "yes" is not the same team that said "no". Apple is a big company. There's more than one person there.

Either way it demonstrates that their judgement was flawed

Or their judgement is sound, and they correctly assessed that the weirdness of f.lux or the thresholds of their userbase had changed in the intervening 7 years.

IF they first approached in 2009 and then had years of promises it follows that the intervening years should be 5 at the most. but maybe quite a bit less.

Ah, yeah, good catch!

I think it doesn't really eliminate the possibility, though, with different numbers.

Flux is still so much nicer than Windows 10's Night Light feature. Flux is gradual and has a transition over a few hours while Night Light has a transition over a few seconds.

Not to mention, with flux you can get the schedule just right. I work night hours, so it’s a light shade of red. But around 1:30 am it gets really, really red. It 1) tells me I should go to bed if I want to be functional when I wake up. 2) I don’t need to be paying attention to the clock and incidentally rush some work.

Every couple of years I see a comment like this and give it another chance, but I honestly cannot tell a difference. Other than the annoyance it gives me with taking the contrast out of everything and de-colorizing my syntax highlighting. Maybe it makes the experience less attractive so I tend to use the computer less late at night, but other than that, what is the big deal?

You sort of have to go full sleep hygiene mode for it to work.

I use flux, but I also cut all blue light after 10pm. I use 1850k lights (aka candlelight) throughout the house after 10pm. My phone is also yellow shifted and I watch tv yellow shifted too (by only watching from a computer with flux at night).

All those things together made a huge difference in sleep quality.

"Does it help you sleep?"

"Yes. Mainly when I practice good sleeping habits, though."

/s :)

It's part of an overall routine. Like how they tell you the cereal is just part of complete breakfast, as long as you add milk, fruit, and a some eggs. :)

But then how do you know how much of a role Flux is contributing (if at all) to the effectiveness of that routine?

If I use non-flux screens but change nothing else my sleep is a lot worse.

And when is your target time to go to sleep?

1am sleep 8-9am wake up.

Why do you go to bed at 1am if you only sleep from 8 til 9am? ;)

he goes to sleep at 1am, and gets up at some time between 8 and 9

Yep, between nights I use my computer late and those I don't, I see no difference on in sleep patterns or next day fatigue etc.

I think it's probably much more of an issue for people already susceptible to inspect insomnia or other sleep issues.

I've found that the effect of sleep deprivation and fatigue in general tends to lag by one full day on average, which makes it harder to mentally correlate between causes and consequences, especially when you're tired. In other words, my alertness on Monday mornings directly depends on how much I slept between Saturday and Sunday. OTOH it also means that I'm able to pull an all-nighter if necessary, but the adverse effects will kick in one day late.

F.lux, Windows 10 night light and Android's bedtime mode are great distractions at best and to me they serve more as a bedtime reminder. I feel that most sleep assistants and other life-hacking tools are mostly placebo that give you the feeling you're in control, which is a state the human brain likes. Sadly, it also means that once you know the placebo effect, those tools become useless. :-)

Reducing the light temperature is not enough. After 8 pm I turn off all harsh lights in my home and avoid things which excite me. Evenings I often tell my wife to postpone lively debates to the next day.

All this makes my body ready for sleep and at 10 pm I feel relieved to close my eyes and dozing off. I have accepted that I seem to need more sleep than others. Usually after 8 to 9 hours of sleep I wake up on my own.

> Once you use it, you can't go back.

I did and I went back.

It does very little you use night mode everywhere.

It might help with white backgrounds but I remove or avoid those even during daylight. I do use the 'Eye saver' mode on my smartphone, but only to visually let me know that it's after midnight.

Redshift is the free alternative for GNU/Linux.

I read recently that light brightness is also very important in regulating circadian rhythm; not just blue light. I'd recommend f.lux or similar + dimming your screen until just before the point it's too hard/straining to read things.

Flux needs to decouple it’s dimming timings from your local day/night cycle. I don’t care if it’s light or dark out, if it’s between x and y time I want the screen dimmed; otherwise, I don’t want it dimmed.

For a non-day-aligned f.lux to actually help you, you'd need to have blue-light filters on your windows, such that you aren't getting natural blue light during the day. Screens have only maybe 1/1000 the lux of daylight. Letting in even a little bit of daylight (e.g. through blinds) would completely swamp any effect from blue light on an LCD/LED panel.

What about the inverse? It's dark outside, but it's 7pm and I'm not about to sleep.

> blue-light filters on your windows

Yes or good old fashioned curtains or window blinds.

People said that, and flux and other apps came out. Then Apple added it too (and perhaps other OS makers).

But there's this too - and increasingly more stories like it:



Interesting, thanks for sharing those articles. redshift lets you adjust brightness in addition or instead of color temperature (there is a Windows version but it is command line only, doesn't look like it supports macs and does not work with Wayland). Someone mentioned brightness a while back and I've been adjusting both since then but I'll try just adjusting brightness and see how it works. If nothing else, it is possible that warm color temperatures might end up being similar to the issue with flashlights where full spectrum lets you use a lower brightness than red light (of course, with flashlights there is also the issue that many "red" flashlights, even some that advertise as being night vision preserving, aren't in the right range to actually preserve night vision). It does seem like I could lower the brightness a bit more without the warmer color temperature.


There's a GUI redshift for Windows: https://github.com/maoserr/redshiftgui/downloads

if anyone is interested, Michael from f.lux provided some great info in relation to the study the above links are referencing when it was originally posted on HN:


I also have a positive experience with Redshift, and use it on both computers and phones at night. Since I live in the north, I also have good experience with "rubber curtains" that block out all sunlight at night in the summer, and a "wake-up light" that simulates sunrises in the winter.

Lots of laptops and OLED phones flicker in low brightness, using this actually make it worse as your eyes strains quickyly from the combined effect, at least for me.

I'm currently using Iris Pro in max brightness, in which the display doesn't need to flicker, the software still can dim the screen itself.

Do OLED displays flicker? I thought it happens only with LED backlight panels that were dimmed using PWM, which was quite unpleasant when I switched from a CCFL one.

Most OLED displays use PWM, as the color dots are hard to control, PWM has no issue in this regard.

I remember installing flux when dealing with a very severe bout of stress induced insomnia. I kept struggling to fall asleep and then giving in and playing temple run until 7 in the morning

I wish we had a non subjective way to quantify sleep quality.

Having children took me from being able to sleep any time anywhere to having horrible sleep. One of my kids had an incredibly quiet voice in her first three months AND had a habit of spitting up copious amounts when we would put her in her crib. She would start crying and making choking noises but very quietly so I learned to be an incredibly light sleeper. She also would not sleep for the first month unless she was held (she got over it, it wasn’t a big thing, it wasn’t a medical problem, we checked), but it meant that I would stay up holding her and watching TV until 3am and then hand her off to someone else for the rest of the night, getting 4-5 hours of sleep. We sometimes had to keep lights on all night, sometimes TV on to keep adults caring for the kids from falling asleep themselves. It was brutal.

A part of it was the breast is best craze that has taken over parenting. I don’t disagree with it, but also some people just don’t produce enough milk to fully sustain a child and you need to supplement. When our kids were older my partner found out that her doctor actually noted that her breast tissue was likely to not produce sufficient quantities of milk on her medical chart, but failed to ever tell her. Hence feeding the kids 8-12 times a night, times two kids.

As a result years later I now can’t sleep for more than 5 hours a night without waking up and not being able to go back to sleep for an hour or two. I am slowly figuring out ways to combat this but I have yet to find a solution that lets me sleep a full 7-9 hours my body seems to actually need that doesn’t give me a headache or make my drowsy for the rest of the following day. Sometimes being human is a limitation.

Fuck all the people responding to with shameful posts about breast feeding being better. I did a fair amount of research into why, and the only conclusive thing a found was that breast feeding increased IQ by like 2 points. That is massively insignificant. IF breastfeeding adds antibodies (which is debated), then that is more than offset by just being careful to not let your child be exposed to the flu. The happiness of your child long term is by far the most important thing, and if being able to sleep better allows you to be more attentive to your child's emotional needs, then that will drastically out way 2 points of IQ. Most people telling you breast milk is better probably have no idea what it is like to feed a baby 8+ times a night and the emotional and physical toll associated with that. That type of situation can make you resent your baby. These people probably read about breast is best on some inlfuencer's blog or are parroting back some advice that their doctor gave them based on their particular situation. A mother who can't breastfeed for physical (or even emotional) reasons doesn't need an arsenal of people explaining to her why she's damaging her baby everywhere she looks to add on to the shame and inadequacy that she already feels. /rant

I have a buddy who did a few years in the military, in one of the more stressful specialties. He had an especially damaged sleep habit as well from this.

He went to some sort of "sleep therapist", I forget the exact nomenclature. Anyway, he was recommended a series of tips (from limit screen time to everything else you may see online). He found it did help. That sort of service may be worth looking into.

> I now can’t sleep for more than 5 hours a night without waking up and not being able to go back to sleep for an hour or two.

Have you ruled out alcohol? I’ve heard drinking at night can cause that.

Other sugars too, the blood-sugar drop signals wake up and eat. iIRC

I don’t drink most days, and if I do I don’t get drunk except maybe once a year.

>Have you ruled out alcohol? I’ve heard drinking at night can cause that.

For the over whelming majority of homo-sapiens alcohol tends to increase, not decrease, the propensity to sleep for many hours. Sure there's edge cases but they're rare enough and hard enough to differentiate from other problems that nobody should be trying to diagnose those over the internet.


Breastfeeding "destroys the tits"? It's literally what they are for. If you can train your child to not bite after teeth start coming through, some women breastfeed for years.

Also, you're wildly overestimating what science can do. With many things relating to the human body, it's like we're in the dark ages. For example, tt wasn't that long ago that Chromium was viewed as unnecessary, but now we know that it is essential for regulation of insulin activity.

Also, in term of "breast is best", breastmilk reduces chances of SIDS. Supplementation with formula should probably be used more than it is, but if you want to have the greatest chance that your baby wakes up, use breastmilk if you can.

This is being purposely dense. The entire planet of men disagrees with you that the only purpose of the breasts is for breasfeeding. I guess sex is only for making babies too. Jesus called, he wants his bible back.

We've banned this account. Would you please not create accounts to post flamewar comments to HN? It's not what this site is for.


Formula is pretty close but the antibodies are a big deal, especially early on. It’s a good idea to breastfeed or pump if at all possible, but it’s not possible for everyone.

My wife would spend hours pumping (baby wouldn’t latch) and only produce a few ounces. We always started with that and then supplemented with formula. The kids seem fine.

On the idea of a wetnurse being “gross”, do you drink cows milk? Because that’s basically like having your own cow wetnurse. Sharing milk obviously isn’t for everyone, but don’t dismiss it offhand.

Ingredients aside, the data is very strong on health outcomes for breast fed versus formula fed babies.

ok, so can you link any data that is from an actual scientific peer-reviewed study, which takes out the cases where babies were fed formula with poison in it? because i gotta tell you, in my 3 years of searching -all the real data for a formula that has been analyzed safe by a lab, says formula is just as good as milk.

Google scholar is your friend.

Breat feeding is associated with a (small) difference in IQ: https://onlinelibrary.wiley.com/doi/full/10.1111/apa.13139

Just search breast vs formula milk systematic review on Google scholar and you should be able to find loads of studies.

so, this tells me that in studies that corrected for the mother's iq, the difference was 2.6 points. My wife is asian, i am jewish, with a lot of phds in the family. This is an increase of less than 2%. Sorry, but there's no way I'm going to believe a study like that has an error/variance of under 2%. The studies also did not correct for the father's iq. The father is not serving the breast milk, but iq of the mother is not "passed on" through food, so if you're correcting for mom's iq, you're correcting for genetics, and the father is half of that. None of the studies corrected for quality of formula.

Dude, you said there was no research, so I found you research.

What you choose to do with that research is entirely up to you.

From want I could tell milk is still better simply because basically only the things we’ve identified as nutritionally significant have been added to to it. Imagine a time before we knew what vitamin B is so we didn’t add it to baby formula. Then it turns out it’s not just a thing but actually important. That’s where our understanding of nutrition.

Another concerning thing with formula is how it’s made. For example, one brand of top shelf organic formula used a chemical known to be a neurotoxin but claim that they remove it all before the manufacturing process is complete, while a competing top brand was using palm oil as one ingredient which is know to be an irritant to newborn’s GI system. So it always felt like choosing the lesser of evils.

Two kids, both on formula from day one. It was probably the right choice for a number of personal factors: we both could easily take turns feeding, it’s easy to know and track how much they’re consuming, and simplified things for eventually going to daycare.

There are certainly people who will discourage you from formula. But you have to make your own choice for yourselves and your baby. But frankly neither choice is “bad”.

> In 2019, Fu and Ptacek discovered two more genes connected to natural short sleep, and they’ll soon submit a paper describing a fourth, providing even more evidence that functioning well on less sleep is a genetic trait.

Several years ago I was listening to a Freakonomics Radio series where they interviewed a bunch of big company CEOs, and one thing that I noticed was they all described their normal routine as involving very little sleep.

It struck me then that being a high power leader is almost certainly genetic in the same way that genes for height are essentially required to be a serious / professional basketball player.

I struggle with sleep, always have, and rarely feel good in the morning without about 8 hours or more in bed. And I’m acutely aware of many of my friends and peers who need much less than this and feel fine. Occasionally I’ll find myself at a conference or something and the group I’m with will stay out late and then get up early and go about their day as normal. I used to try and keep up, but I would be so hung over the next morning (regardless of whether I had anything to drink) as to be non-functional.

It’s a sad thing to me to think that I don’t have the genetics to keep up with the people who need a lot less sleep than I do. However, I’m gradually making peace with it, as I focus on finding things I can do with my life that are compatible with my need for more time in bed.

Well, Marissa Mayer is quite preachy about working long hours and sleeping poorly. She always had important roles in big companies, but he managed Yahoo quite poorly. So she fits the narrative ("no sleep -> CEO"), but that doesn't mean that you will be CEOing correctly.

I'm sure there are other good CEOs that sleep 8 or more hours, but they don't talk about it. I hide the fact that I like to sleep at least 8 hours (but 9 would be my optimal), because sleeping 6 hours or less is a medal in my workplace.

I only know of Basecamp CEOs that take the opposite stance: they admit to sleep at least 8 hours, take long vacations, having cool hobbies and healthy families, working 40ish hours per week... while keeping their bussiness running happily on profits for 17 years in a row. And boy did they receive criticism for saying it out loud. Nonsense like "if you worked harder and slept less, your bussiness would be billionaire instead of millionaire".

Tobias Lütke from Shopify is another one you can add to your list that's gone on record about getting decent sleep. https://www.cnbc.com/2019/12/26/shopify-ceo-you-dont-have-to... :-)

I've noticed that higher energy level seems to be the x-factor for some of the materially successful people in my orbit.

My sister simply can. not. sit. still. Not ADHD or whatever. I mean she always has to be in motion. On the move. Doing something. So whereas I'm a daydreamer, in the time I can imagine 3 ways to do a thing, my sister has already tried at least 6 options.

The Big Boss at one startup was a pretty good sales guy. Not especially smart, but good hustle. Yes, we had all the standard problems of a sales & marketing driven org. Over time you get to really know someone. Offline, holidays, birthday & release parties, etc. This Big Boss was always in motion. Never idle. I remember one time just sitting there, watching him in action, marveling at his boundless energy. He has at least 3x my physical energy level, and many people say I exhaust them.

The analogy I think of is higher energy people have more bites at the apple. So just by playing the odds, they'll succeed more often.

I've wandered about the psychology of this forever. Is it a bias towards action? Whereas I can think of 100s of ways something will fail, my sis just acts and learns quicker thru action. So is that a bias towards failing faster?

I dunno, but I'd love to find out.

Recently someone told me his theory. People with thick skin don't need sleep that much. People with thin skin, who are quite receptive, need a lot of sleep.

I can imagine that someone who is CEO also has quite a thick skin and doesn't need to sleep that much. It seems to fit that theory :)

Also, many try to close the genetic gap here with drugs. Many "leaders"/ high performance people are constantly coked up or on amphetamines.

I also need closer to around 9 hours of sleep. I am also a relatively light sleeper for a part of the evening, so I need things like ear plugs, total darkness etc. and I guess part of why I need more sleep is because for part of the night I probably get poor quality sleep. If I do get too little sleep I really struggle very badly compared to other people equally sleep deprived. I have ADHD and when sleep deprived it gets significantly worse and I get very anxious not being able to manage priorities and responsibilities. That said, even though I don't think I'm cut out for leadership positions I certainly have enough coping strategies to take advantage of the times I am functioning well enough not to feel like I've been left behind. Also, not everyone has to become a CEO.

After fighting my body my entire life to fit with the mainstream, I switched to a 20-hours up, 7 hours down sleep schedule six months ago. I've never felt better.

Instead of feeling like a zombie until 5-6 hours into my day and working late into the night, I now can find myself working minutes after waking up - something I never thought possible.

I'm roughly twice as productive as before.

It is admittedly difficult to plan ahead; I don't have dependents and I am a solo developer, working on my own schedule.

One silver lining of COVID is that people are finally getting a glimpse of what post-9-to-5 cubicle work styles can offer.

Why shouldn't we work when and how we are most productive?

I've noticed the same thing myself at various times in my life. My most frequent sleep schedule I maintained was 4am to noon, but it drifts from that pretty often. And when it does, my days push longer. I actually mapped out a "6 day week," where I would sleep 8 hours and be up 20. It lines up with a 24/7 week where I wake up at the same time on the same day each week.

Thank you for posting this. It's encouraging me to consider giving that a shot again. (especially since I woke up at 5pm and that's been pushing later again)

John Carmack was following this routine and some days he would come to office in the evening when no one was there and will leave before any one arrives.

Sounds interesting. I've often noticed that I sleep much better when I stay up longer than usual. I have commitments during the day that would prevent me from doing this though. Did you come up with the idea yourself? I didn't find anything on the web about it.

I spent 25 years feeling tired all of the time. Chronic night owl, I would find that my most productive periods would come precisely when I was "supposed" to go to sleep. I could either lay in bed, wide awake and frustrated, or end up destroyed the next day, which was basically every day. I'd try to catch up on weekends, but you'll find plenty online about how poorly this actually works.

What changed is that I noticed how, left to my own devices without external schedule pressure, I would naturally drift 3h forward every day - and so I realized I had the opportunity to actually fully go with the schedule my body seemed to want to have. I informed my family what I intended to do, cleared my calendar for the next week, and went for it.

First observation: my biggest hesitation was social judgement. I was consciously aware of how little I wanted people to think I was a weird dude.

Well, turns out I'd rather be weird and feel great than normal and feel like a zombie. My body almost immediately seemed to breathe a sigh of relief and six months later, this part of my life is amazing.

I find it endlessly curious how some people seem seriously distraught when I tell them what I've been up to. Not because they have any medical opinion, but because it appears to challenge something that clearly gives them a feeling of being normal.

My doctor actually had very little to say, once they heard me out and read the research I gave them. Essentially, "please stop if you start feeling bad".

Apologies, could you elaborate a bit more with a few example times? How does it all work?


Feel free to ask more specific questions.

Relevant xkcd: https://xkcd.com/320/

Can you explain it more?

Sure: what would you like to know?

Off the top of my head:

- easier to find the will to exercise - less cravings for junk food - depression symptoms occur 80% less - back pain frequently forgets to manifest - I feel more optimistic

It's not all roses, though. I am not traditionally employable because I work unpredictable hours. It can be hard to schedule doctor's appointments, for example.

The hardest thing is syncing with my SO. She's actually inclined to keep similar hours, but has a 9-5 job. Still, this hasn't been a huge issue.

I don't think it could work if you had young children.

I'm going to join in as shifting your sleep pattern by 3 hours a night, if I've read it right, sounds (without meaning to be at all rude) a bit crazy.

How did you decide to choose this pattern? Did you hear about it or was it part of a process, or did you stumble across it?

I can appreciate how it might sound unsane if you've never dealt with sleep issues (jealous!) or read a ton about it. Ask away, but I did cover a bunch of these elsewhere in the thread: https://news.ycombinator.com/item?id=24185624

That's really interesting. I'm also jealous because I've had terrible sleep problems to the point that your choice of craziness would look less crazy! :) I've found that if I go to sleep within the same 15 minute window every night then I will wake up some time within the 3 minutes up to my alarm going off, often just a few seconds before.

If I don't then my internal clock will immediately shift later and it's incredibly hard to follow the "old" pattern. I think I can get away with one late night every so often but never two. Right now I'm stable but it's very hard to convince the people around me that it's what I need, even though they've seen the effects of not doing it. I believe it's in the same realm as smoking or alcoholism, where if you have a problem then most people will say "why not stop drinking then?" as if that's some great insight. "Just go to sleep" isn't particularly helpful.

And then, of course, they'll fall asleep with no problem and complain if they feel crap after one bad night :/

Really glad to hear you're feeling good on it! I hope it stays that way.

More so what time do you go to bed and wake up, etc?

I go to sleep 20 hours after I wake up, and I wake up 7 hours later.

I have a non-24 hour circadian rhythm and I think they are usually if not always closer to 24 hours than to that, but it is an interesting idea and as someone who also has bad insomnia I can see the appeal. However, one thing to keep in mind for anyone who doesn't already have Non-24 is that it may be that Non-24 has both a genetic aspect and a trigger and trying something like that could be the trigger that prevents you from sleeping on a 24 hour schedule again. I encourage everyone to be careful with your circadian rhythm since messing it up causes major problems (in my case, I get the strong sense that there is an issue with syncrhonization and different parts of my body shift at different rates and some parts synchronize with the sun). Also, some of us with Non-24 find it harder get to sleep during the day and I'd guess that would be the case for many people on this type of schedule (it might not be possible to keep a by-the-numbers schedule).

Some good points!

I am not a doctor, but I have spent a lot of time in sleep clinics and reading about sleep. I am also quite familiar with the huge number of issues surrounding the relatively recent book "Why We Sleep" which is essentially considered partially-debunked at this point. I feel about that book the way most of us would feel about a book declaring that people who code or are interested in startups are missing opportunities to play more football.

My rhythm seems to be off by two REM cycles eg 1.5hx2, and I actually find 3h pretty easy to manage as it loops around every 7-8 days.

I don't have any trouble falling asleep during the day, because I own a https://nitehood.ca - the discount code is August15 BTW.

I agree with at least most of the criticism of "Why We Sleep" and haven't read the book. My concerns about messing up circadian rhythms have nothing to do with the book (other than that some of the advice in the book seems to encourage some people to mess up their circadian rhythm). I am disabled due to sleep issues and have met a few others who also have severe issues due to circadian issues (some people with Non-24 do fine if they can keep a Non-24 schedule). It is at least possible that for some people experimenting with a non-24 hour schedule could cause a permanant Non-24 condition so anyone considering trying such a schedule should be aware of the potential risk.

For me (and I'd guess many others) a sleep mask does not make it much easier to sleep during the day. I would need to have a dark environment for a while before sleep. Some people can set up a room like that but I can't at this point. This is not to say that I never get to sleep during the day, but I stay up longer when I go to sleep during the day, even if I have been awake for a while. Some people with Non-24 have the same reaction I do and others don't.

Honestly, that sounds like hell. I'm so sorry that you're going through this.

I am very lucky that I am able to control my environment - I have blackout curtains on my bedroom window, which is where I work.

> I don't have any trouble falling asleep during the day, because I own a https://nitehood.ca

Did you end up with this randomly or do you find it better than regular sleep mask?

I don't know about random per se... I admit that I saw it on Instagram after being frustrated by 3 sleep masks that would just come off while I was sleeping.

I love the NiteHood. It's objectively awesome in terms of function, density and even material choice. 10/10

So if I’m understanding correctly, do you end up doing a full 24 hour rotation every 8 days? Very interesting - how do you plan your week?

It can be hard, TBH - I actively minimize distractions anyhow, but this is on a different level. It's probably not for everyone.

That all said, statistically I'm much more likely to be awake than not during the day, so many folks would have no idea. Usually there's only one day a week where I'm essentially going to sleep right when everyone else is starting their day.

I'm lucky that my daily shift is 3h - two REM cycles - as it maps nicely onto the 24h schedule everyone else is on, most of the time. 1.5h or 4.5h would be really confusing to me.

> [S]hort sleepers may actually have an edge over everyone else. Research is still early, but Fu has found that besides being more efficient at sleep, they tend to be more energetic and optimistic and have a higher tolerance for pain than people who need to spend more time in bed. They also tend to live longer.

And, here I am needing my 8±1 hours every night. Even needing half as much sleep alone would be a real edge. Tack on being naturally more optimistic and having a higher pain tolerance than others, and it starts sounding like a real superpower. Oh, and they live longer, too?

This is exciting research, but I can't help but feel either envious or inferior because of it. Yes, it's a personal failing. Sue me. :P

My real hope is that this research eventually benefits medicine somehow. Maybe they can put it in a bottle for the rest of us (unlikely!). Or, since lack of sleep is linked to so many conditions, including systemic inflammation, maybe we'll get some insight into what the relationship is between sleep and inflammation? Maybe a "sleep gene panel" will become a standard test and guide how we treat certain conditions? Who knows.

It sounds like half the advantages, at least, are benefits of sleeping as much as you need. If I don't sleep enough I'm grumpy and apathetic, so if I only needed to sleep 6 hours (instead of 8+) I'm sure I would be happier.

So I believe this might have done causation link.

I find it almost impossible to sleep more than 5 hours in one night, but I feel great all day and never feel tired. Exercise for a dozen hours per week and have good discipline with putting away the phone at night, etc.

We are always told how bad this is, but there is no solution offered which actually works and I've never experienced a downside. It would be nice to prove once and for all that it isn't harmful for us all.

My friend is the exact same as you. She’s only slept 5 hours a day for her entire life. Any more and she actually feels groggy.

She pointed out one reason why that may be the case: https://www.ucsf.edu/news/2018/03/410051/scientists-discover...

That's the same researcher being talked about in this article . They've identified more gene since then. That's the story here.

I'm fairly close to this. I used to require almost exactly 4 hours of sleep a night, and getting more or less than that made me feel absolutely abysmal, but over the years it's jumped up to 5.5 hrs/night with it being slightly more forgiving about the range (from 4-6 hours I feel decently okay, best at 5.5 and worse as I fall away from that, but outside of that band I feel completely horrid). I get more rest than this, but the extra hours of rest are usually laying down listening to music or the occasional audio book.

I think the biggest agent of change is my autoimmune disease which has worsened over the years and now requires of me more rest and sleep maintenance.

Got a cruel reminder of all of this sleep-related business last night with the bay area thunderstorm waking me after only 3 hours of sleep and the storm and heat keeping me awake until my body screamed for a rare noon siesta.

I'm someone who needs a lot of sleep, like 9h minimum, so that I feel good and energized during awake time.

I'd say, if you feel well rested, energized and just overall feel good when you wake up, you don't have any issue.

Similarly, I have found that every hour of exercise removes the need to sleep about an hour, to a certain point. Unlike you, though, several hours a week of exercise brings my nightly need to sleep down to 8 from 9-10!

I think it may depend on how strenuous the exercise is rather than the duration, but I have a similar observation. I normally sleep 6-6.5 hours at night. When I did p90x (45-60 minute sessions) a few years back, I would usually be wide awake after 5 hours. I suspect this is because I sleep really deeply when tired - I remember most of those nights sleeping dreamlessly.

That is a good point. As someone who naturally sleeps longer then 8 hours, my exercise is not as intense as it probably should be.

I’m going to guess that you’re under 30.

Similarly, I feel cheated. We were always taught growing up that kids need more sleep than adults and older people. As a teen into my mid 20s, I never slept more than 4 or 5 hours a night and felt great. Now, if I sleep less than 7 hours, I have to drag myself out of bed and feel sluggish for the first half the day.

Not the OP, but I am over 40 and I only sleep 5-6 hours a night. I am never tired during the day, never drink caffeine. I do a TON of cardio, especially massively long bike rides on the weekend.

It's interesting the parallels between us. I'm about 40 and sleep 5-6 hours a night. Never tired during the day, never drink caffeine (ironically, I sometimes drink it in the morning in hopes I'll crash and fall asleep). I do an enormous amount of cardio, on bikes!

It's 1:17am for me. I will be awake for another hour most likely. I'll get up before 8am and ride for a few hours. Never a yawn. It's really fascinating and I have no idea how to explain it.

You're a lucky b. :)

I'm really jealous of you. I need 7.5 to 8 hours of sleep. I would feel like a zombie if I got less than that. If I could only sleep 5-6 hours of sleep, I would do more things in my life: studying foreign languages, working on side projects, reading more books, etc.

It's all relative. I would encourage you to feel moderately lucky yourselves, some of us need 9-10 hours :-/

Nearly 40

If there is anything that I realized after reading so many (apparent) researches on dietary habits, sleep cycle, exercise, and whatnot is that you are unique and you do what works for you. Most of these are just average(as in expected value) results that are extrapolated out of a superficial survey, which they call study; and some of these are outright bad. Yes, there are general heuristics like being disciplined with your time and effort which if followed can be beneficial, but most of us will have to go through the suffering to discover that; and fwiw, you'll eventually discover that on your as you age and see that your (unrealized) slothfulness, carelessness and temptation is harming you more than you think they are.

I use to work at a seed stage startup, where I had to grind out days together without sleeping and eating, because of which I suffered from severe health issues mostly lifestyle related. I browsed through every blog, every paper, every podcast and youtube videos I could get my hands on --- tried all of them over a period of 2.5 years to a deteriorating health and increased stress. Luckily 2 years ago, I went to a Vipasana silent meditation retreat, where for 10 days you eat on time, sleep on time(9pm), wake up on time(4:30am), and meditate rest of the time. I don't how that retreat itself helped me, but I somehow managed to adhere to that schedule for 2 years now and I feel better than ever.

NB: I don't meditate all day, but I meditate 1 hour every day while also maintain my eating habits and sleeping habits.

"I read an article saying not everyone needs 8 hours of sleep!"

"You are gaining weight, not finishing your work, and you had a car accident last week."

"I feel fine on 5 hours of sleep, shut up!"

Yeah, this is pretty much my experience with people who loudly claim they dont need to sleep much.

There is imo bias in play tho, the loud "I sleep little" people do so because they picked up that working or playing till night is cool thing to do. Which has little to do with their actual sleep needs. And the bragging has a bit to do with diminished self control due to sleep deprivation.

Meanwhile, people who actually need to sleep less, would just ... sleep less without talking about it or even realizing it, so you will never know.

It's obnoxious to approach such a complicated domain with the attitude that you are right and people who are thriving are wrong.

The problem is that people who are sleep-deprived tend to believe they are "thriving" (or at least "feeling fine") when they are very much not.

If they're happy and productive and generally satisfied with their life, I'd call that thriving.

If they're struggling, occasionally (or more) depressed, unproductive or unmotivated, lack meaningful social interactions... Sleep could be an issue. Or it could be the depression that is in turn causing the sleep and other issues. These things are complex.

Here is key:

> "You are gaining weight, not finishing your work, and you had a car accident last week."

And I have seen this in play. Otherwise smart person coding stupid things, saying stupid things, getting overly emotional and angry over stupid things all the while proudly claiming the 6 hours a night are enough for him.

And blaming everyone and everything for all the problems, just not himself.

And everyone else is unhappy due to consequences. And him unhappy due to constant conflicts he is in that he does not really understands. But like, those were totally not his fault, they were everyone elses fault.

It wasn't a sleep issue but I felt like I was thriving when I was doing 4 hours of hard exercise per day. I burnt myself so hard I went down with glandular fever that then led into a year of post viral fatigue (chronic fatigue). I'm much more sensible now and listen to my body.

You can downvote me all you want, but the before and after for my lived experience speak far louder than your petty retribution. I have come to notice that many people seem personally offended by the very idea that sleep is not a one-size-fits-all scenario.

As I explained elsewhere in this thread, after fighting ever-present grogginess for my entire adult life, I switched to a 20 up / 7 down schedule six months ago. My output has doubled, my depression has gone away, I have more energy for exercise and I crave sugar and carbs far less.

You should do what works for you instead of getting upset when something different works incredibly well for me.

You can downvote me all you want

@yjftsjthsd-h can't downvote you at all, HN doesn't allow you to downvote replies to your own posts.

I think OP was just saying that even if the article were true, it didn't mean that someone who claim to be one of those people actually were.


A common suggestion, also in this thread, for increased sleep quality is limiting screen time or any stimulating activity before bed time.

But what to do then? Talking to housemates might be ok, but what if you have none, or the conversations end up stimulating? Similar for books. The books Im usually interested in (non fiction) tend to be very stimulating. I remember fiction to be quite stimulating, too.

I guess the crux of the problem is, how do you stick to doing something that is boring on purpose? And is the improvement in sleep quality really worth it?

My take is that it's about the "stimulating activity" rather than the actual screen time. When broken down it's intuitive, but the "reduce screen time" adage often gets repeated without that distinction.

Specifically about your problem: for me, I move from a state of "active engagement" to "passive consumption". 1 to 2 hours before bed, I stop doing anything engaging that requires my active participation - work, video games, learning. I shift to lounging on the couch and reading fiction or watching a movie/show. The key is in my intentions behind each: in the evening, my goal is to relax. I dont turn on a movie with the intention to learn or to be entertained; I'm just there to experience it.

Sorry if that's too abstract; the feeling is hard to communicate. Hopefully it's a useful starting point for further thinking.

It's actually very helpful advice. Thank you.

A few things that come to my mind now:

1) I did notice though that some form of learning, e.g. vocabulary, can help me fall asleep. I guess it requires focus - which makes me feel tired - but is also dull. 2) Reading in low light conditions makes my eyes tired. It feels harder to keep them open which can work as a trigger for sleeping. It's not bad for eye health by the way [1]. 3) The biggest hurdle often seems discipline. It's just too tempting to continue a fun and engaging activity, like playing video games, way past bedtime. The easiest solution would be to not engage in them at all in the evening, but then you might never find time for it.

[1] https://www.health.harvard.edu/healthbeat/safeguarding-your-....

> It's not bad for eye health by the way [1]

Do not be so sure about this. http://www.myopia-manual.de/ has a lot of information. Page. 131ff:

>The development of chicks towards emmetropization was observed at various levels of illumination [544]: (10.000 Lux, 500 Lux and 50 Lux). Result: After 90 days 50 Lux resulted in a mean myopia of –2.41 D, 500 Lux resulted in +0.03 D, and 10.000 Lux resulted in hyperopia of +1.1 D.

>Categorized according to their objectively measured average daily light exposure and adjusting for potential confounders (age, sex, baseline axial length, parental myopia, nearwork, and physical activity), children experiencing low average daily light exposure (mean daily light exposure: 459 ± 117 lux, annual eye growth: 0.13 mm/y) exhibited significantly greater eye growth than children experiencing moderate (842 ± 109 lux, 0.060 mm/y), and high (1455 ± 317 lux, 0.065 mm/y) average daily light exposure levels

I had to learn to love those boring things for the positive outcomes I got from them. It's nowhere near perfect, but I know if I do all the right things during the day, I will get a decent sleep. There are some things that help more than others. There are also things that I can't always commit to since I have a lot on my plate (I'm still balancing whether I need all these things).

For me, these boring things are: * Making and drinking herbal tea (just don't get _obsessed_ with tea) * Doing dishes * Organizing my physical space (mail, books, backpack, papers, clothes, shoes, et al get moved during day) * Talking with partner * Catching up on texts before 930 * Reading fiction (or non-work non-fiction) * Listening to music (sometimes I listen to audiobook/podcast at night but rarely) * Sometimes making food for next few days or making grocery list

We had to talk about not having stimulating conversations before bed and are working on that. It's a real challenge, especially if you end up not seeing each other all day. You have to talk about it with your roommate or partner and talk about the problem you're trying to solve, offering that as a solution.

My day is designed to get me to bed having checked off my list of important things and feel tired for bed. It's essentially designed to add in good habits and take away bad habits so that I sleep better. I've worked on it for a few years and it has paid off.

I used to work overnight and trained myself to get better at sleep. It's more than just limiting screen time. I started sleeping better when I created an entire process that signaled to my body that it was time to sleep.

An interesting aside: circadian rhythms often group in multiples of 1.5 hours, and I can say from experience that it is better for me to get 7.5 than 8 hours

Hell, disrupting REM mid-cycle is worse (in my experience) than fewer cycles that are all while: better to get 6 hours than 8.

Sorry to be a bit pedantic, but circadian rhythm is "a natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours." I believe you meant REM cycles, in your first sentence (which matches up to your next sentence).

You’re right! I’m just some dude on the Internet... :)

That kind of fits my experience. I used to wake up around 7:15. Now with COVID work from home and no commute or need to go through a morning routine, it's naturally turned into about 8:45. Pop up, grab some food, do a few hours of work, then take a break to shower, change, etc. I'll have a tough time when I have to return to the office.

This has been my schedule since COVID, too, almost to the minute!

At first I felt really weird about working before showering, like it was out of order so it felt wrong. Now, I can’t imagine doing it any other way. Weird!

I’m usually done with breakfast and tea around 8:45, and then I work through until noon. Go for a run if the weather’s good, shower, quick bite for lunch, back to work till 6ish.

I used to get in to the office around 11 before, regardless of what time I woke up. I can’t help but feel the current (weird) schedule is at least 20% more productive for me.

Yea, the office readjustment will suck.

True, I started waking up much better with one of those apps that wakes you up when it senses movement. It has reduced a lot the urge to hit snooze.

I used to do this too. Then I realized this only works if you actually sleep 7.5 hours and it takes average human 14 minutes to fall asleep. I.e. I’d set an alarm 7:30 from when I go to bed but then still felt tired - doing 8 hours felt better with 7hrs45ish the sweet spot. Hence I can see why people just recommend 8 because normal people don’t try to optimize to the minute and better to slightly over estimate rather than definitely underestimate

Yes, I need 9 hours of sleep per day, ideally 10. Unfortunately, it is hardly possible to have this kind of schedule when your family are all morning birds.

I feel ya! 9-10 hours optimal over here too. New baby is making that impossible.

I'm also a 9-hour-a-day person. My partner is probably at 7, but gets up quietly. I can function ok with 7, but I'm miserable and much less functional with anything less. Up late packing and up early for a flight? Misery. But, though I won't be going again soon, I enjoy a lot of the aspects of flight and most importantly, I don't have to think much during.

I'm so happy to see this type of research being more broadly accepted mainstream.

We don't have one diet for everybody, one exercise type for everybody, why do we think sleep would be any different.

We're working on improving sleep performance, if you're interested in this sort of thing, sign-up to get on our waitlist https://withbliss.com or reach out.

You could replace Seemay Chou with my my name in that first paragraph. For as long as I can remember I have went to bed at midnight(ish) and have been wide awake and productive around 4-430 without the use of any alarm. Consistently. Weekends and holidays. My family does not understand it, and I do not understand how they allow themselves to sleep in everyday.

I like it like this. I get to be awake and go about my business without interruption when the people around me are asleep. I get much done between the hours of 4am and 8am.

When I travel for work I get to see other cities with almost no traffic on the streets. New York and LA, Atlanta. It has a certain feeling to it. Although in recent years if I happen to be on the streets at 5am I usually notice a fair amount of foot traffic outside of fitness clubs.

At first I saw these people as intruders, encroaching on my little, peaceful world. The early morning has a certain feeling that is somehow diminished with the addition of other people...

> and I do not understand how they allow themselves to sleep in everyday

You are very fortunate with your sleeping needs. What exactly is there for you to understand? You speak about them allowing themselves to sleep in, yet you don't disallow yourself to do anything but just wake up naturally without alarm.

Margaret Tatcher famously only slept for 4 hours, but it’s said she used to nap in the car whenever she could. I think cultures where they take a nap during the day, such as the siesta in Spain, may be onto something. More offices need to have sleep pods.

The issue is we're calling it a 'nap' but it's not, it's basically 'biphasic sleep', before the industrial revolution it used to be the standard.

Sleep, wake up for a few hours, sleep again. This new-fangled 8 hour block of sleep people seem to think they need to do is incredibly detrimental to health.

Yes I do remember reading a while back that this used to be very common. It started dwindling in the late 17th century and was pretty much obsolete by the early 20th century.

This period was often used for prayer, or writing, or sex, or even for visiting the neighbours.

It's not just the amount of sleep that affects us.

For me, the biggest improvement I had thanks to the 'rona lockdowns was I finally can follow a decent sleep schedule - wake me up at 8 or earlier and I'm essentially an unusable wreck for the first 4 or so hours, so when I was able to sleep until 9 because I had no need to rush for eating, showering and to travel the ~45min to work I actually am way more productive.

Now, if politicians could get their butts to introducing 32 or shorter hour work weeks (=4 day work week)... that would be yet another boost, for physical and mental health as well as for unemployment numbers.

There would be other issues like how much we can change our sleeping hours and circadian. The article mentioned it's crazy to say everybody has to be the same height, but nutrition and exercise can influence how tall a children is going to be. Besides our heights, from weight to intellectual performance it's always interaction between nature and nurture.

Similarly, we shouldn't consider gene as an excuse against trying to be productive given fewer sleep hours. On the other hand, it could be better if we don't have to force ourselves or anyone to sleep fewer even if someday there would be a scientific way to do so.

I need maybe 4-5 hours to function and 6 to function well. Anything more than that I feel stressed all day like I missed something. I can typically jump out of bed (literally) at around 6 hours excited for the day and do a full 12 hours of work.

That being said, I have slept 8 hours or so when I am sick or feeling a tad depressed.

My wife in contrast needs 8-10 hours of sleep to feel that way. But with kids she gets 7-8 hours so she’s always a bit groggy.

Ideally We’d sleep without alarms, but our children let us know when it’s time to get up (and there’s some variance there).

I think your body adjusts sleep based on its needs and we should probably listen to it.

The article seems to be too obvious, maybe I am missing some bits of info here.

After I read "why we sleep" all these: "sleep faster", "you need 8 hours", "I wake up at 4am" seems ridiculous to me. It's all depends, try to sleep 8 hours and if 6h works for you - lucky you, if 4am works for you - lucky you, if you need 7h or 10h - good, stick to it and adjust your schedule. Despite all the articles on how bad "why we sleep" is, it helped me a lot, at least with basics, that's all I need due to lack of ambition to get a PhD in why people sleep.

I tried everything, slept 10h, 8h, 6h, mix(night/day) and there always was only one thing that worked for me: wake up without alarm in the "late morning". No matter how hard I try, morning is just not for me, I fought with it for too many years and the war is over, my sleep always wins. Evening works best for me, no matter of what people try to convince or adjust me to.

TL;DR try what works for you and don't try to adjust with others.

> ‘The researchers expected that regardless of the time of day, men in both groups would see improvements in blood-sugar levels. But “when they exercised in the morning, they actually had slightly higher levels of blood sugar [than baseline], which we didn’t expect at all,” ‘

There’s a circadian effect to blood glucose...it’s part of how you wake up. Kind of surprised the authors of a circadian rhythm study didn’t factor this in.

I decided that I really am a morning person and decided to go bed around ~2030 (sometimes at the weekend I’ll go bed later if I’m out with family or something) and I wake up when my body is ready. Usually that’s around 0500. Then I walk the dog for 30-40mins, eat breakfast and then do some studying for a few hours before I start work at 0800.

I do feel much better, and it’s nice waking up when I’m ready without an alarm.

For me, if I don't workout, I just need about 6 hours. If I workout (whether cardio, strength or both but especially with strength), I definitely need 8 hours.

Every few weeks I find myself sleeping 10-12 hours with non-stop vivid REM dreams.

For example, with less than ~9h of sleep my well being is significantly affected.

There are different sleep stages. Some stages are more resting than others.

I highly recommend "Why we sleep" by Matthew Walker. It does a great job describing the science of sleep.

Matthew Walker's "Why We Sleep" Is Riddled with Scientific and Factual Errors — https://guzey.com/books/why-we-sleep/

Thanks for the link, will check it out. I note however that Walker has responded to the criticism (https://sleepdiplomat.wordpress.com/2019/12/19/why-we-sleep-...).

From a quick skim of that response, it reads to me like Walker admits to and agrees with at least some of the criticism.

But it also looks like he ignores some of the more damning accusations, like cutting out parts of graphs that don't support his theories, being incorrect that the WHO has declared that we have a "sleep loss epidemic", and questions about where he actually earned his PhD (which he seems to continually misrepresent).

So yes, he seems to have responded to the criticism, but IMO not really addressed it to a satisfying degree.

All of what you said might be true and it could still be the best book on why sleep is important.

It's also possible that someone who lies 99% of the time has something really important to say with the other 1% (if you can even separate it from the 99%), but I wouldn't consider that person trustworthy or even worth dealing with.

Not saying that perfectly describes Walker, but the evidence does seem to point in that direction.

If you still want to trust someone like that, I guess that's your prerogative, but... well, that sort of thing doesn't seem like a winning strategy in life.

If I'm allowed to just make shit up I could easily write an even better one!

IMO he has mostly satisfying answers. He agrees with some minor points and he doesn't address important stuff like cutting out parts of graphs, but I don't think the criticism is strong enough to conclude that the book is "riddled with scientific and factual errors".

Quality not quantity. Stalin was wrong.

I wouldn't say he was wrong, it's just that the quality/quantity balance doesn't balance the same way in every circumstance. And Stalin wasn't making a universal proclamation.

Of course he was a brutal dictator who caused the deaths of millions, so it's still probably a good idea to take his "wisdom" with a critical eye.

tl;dr 8 hours is a common standard, but you probably need a different amount.

President Trump is famous for boasting about how he only sleeps for 4 hours. He claims that reducing his sleeping time down to 4 hours took a tremendous amount of willpower and effort.

If you do what @jack do, namely eat only once a day at 13:00 hours, you'll start sleeping like a baby again. Long uninterrupted sleeps with vivid dreams. When you wake up you have take a moment to sort out which things are real and which only happens in the dream-world, which forms a static continuum of unique persons, themes and storylines. @jack does not mention these crazy dream issues, because it would effect the Twitter valuation and his own valuation too.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact