7 ms·

Where Human Sleep Went Wrong

130 points by XzetaU8 2mo ago

montebicyclelo 2mo ago
More fragmented sleep, with people talking in the night, etc. I guess that's different from the low, unnatural, rumbles of cars and aeroplanes the majority of people have to put up with.
- Pearse 2mo ago
  I actually find it easier to sleep with the sound of people talking around me, it's very comforting.
- yard2010 2mo ago
  I could only wish for low unnatural rumbles of cars. In 3rd world countries it's non stop horns and noisy motorbikes
  - HappyPanacea 2mo ago
    Car horns gotta be up there as some of the worst inventions of the 20th century, noise pollution galore.
    - jbuhbjlnjbn 2mo ago
      It works when you have strict rules on the use of horns and people get peer pressured into adapting to the behavior of their surroundings.
- abigdog 2mo ago
  737s are fine its dog barking that gets me.
Flashtoo 2mo ago
> Some emerging research suggests Earth’s magnetism matters, as well. Being barefoot on the ground versus 30 stories high in a downtown skyscraper puts you in a completely different magnetic environment. Really? My instinctive reaction to this statement is that it's quackery. Would be very interested to see headlines appear about this if it's true.
- eru 2mo ago
  People already live in different altitudes, ie with vastly different amounts of rock between themselves and the bits of the earth that produce her magnetic field. So colour me skeptical of this claim as well. And while I like going barefoot for other reasons, I don't think it makes much of a difference to the magnetic fields.
  - krige 2mo ago
    > People already live in different altitudes, ie with vastly different amounts of rock between themselves and the bits of the earth that produce her magnetic field. It's not really the same thing. Construction and especially the high content of charged metal (whether it's power conduits or plain old frame) may make a considerable difference.
    - dotancohen 2mo ago
      Do many people sleep in such tall buildings? Obviously they exist, but I can't think of any over-20 story residential building I've ever been in. Office space, sure, but not residential.
      - nkrisc 2mo ago
        The amount of people who would regularly sleep in such a building is a minuscule fraction of the world population.
      - eru 2mo ago
        See https://en.wikipedia.org/wiki/The_Pinnacle@Duxton https://en.wikipedia.org/wiki/The_Pinnacle@Duxton
        dotancohen 2mo ago
        Yes, like I said, these things exist. But I ask do significant populations of humans reside in the upper floors of such structures?
moffkalast 2mo ago
> Sleep is critical to human functioning, and yet, we sleep fewer total hours than any other ape, and are still arguably the most evolutionarily successful of the primates > humans are weird outliers—we’re the shortest sleeping primates, yet we pack in the most REM sleep relative to this short duration Isn't that sort of the point? Sleep is a detrimental necessity and the more efficient an organism is in needing less of it, the more effective it can be because it simply has more time to get ahead of the others? It's still very odd that no species has ended up evolving a continuous maintenance system that can run while conscious, the benefits when hunting other animals that need sleep would be enormous, so there has to be significant evolutionary push for it. I suppose the single hemisphere sleep some marine mammals do is part of the way there, but it is at most a lazy workaround. Practically all other organs have evolved to run 24/7 for up to a century without a single break, what makes brains so universally different?
- deleted 2mo ago
  [deleted]
- salawat 2mo ago
  The fact they electrically signal via chemical analogs fuelled by immersion in nutrient bearing fluid that also accretes waste products, yet is kept separate from the primary loop of the cardiovascular system by the blood-brain barrier?
  - dotancohen 2mo ago
    But why is that fundamentally different from the technobabble description of any other vital organ?
    - salawat 2mo ago
      Life has a surprising amount of detail, and if you're only curious enough to interact with the answer as 'technobabble', this does not speak well of your genuine curiosity on the subject. However, in general... Form is shaped by function. The liver/pancreas are designed to handle the production of detoxifying/neutralizing agents that may in and of themselves kill nearby tissue, resulting in the propensity for notable regenerative capabilities. Kidneys/intestines are high surface area to provide more room for the physical processes driving selective permeability to occur, as well as habitable spaces for beneficial microbial symbiotes that aid in digestion. Skeletal/smooth cardiac muscles are optimized for energy burning to facilitate movement. Tendons/cartilaginous membranes are optimized for lubricating joints/connective tissue purposes. Tissues like the thalamus and tonsils, are there for immunity modulation and detection. Neural tissue however is all about signal propagation, and creating shifting networks of continuity that encode information and patterns, the tissue itself is just the medium, and that medium requires some process to clean out or reset the gradients in the synaptic gap. Otherwise, electrical charges cannot be consistently conveyed as flows of ions, actuated by releases of neurotransmitters into the bridge of the synaptic gap. The other constraint unique to neural tissue as well is it isn't motile, or capable of physical movement. All it can do is carry charge by a process of chemically modulated action potential building, yet also needs to have a means to carry out adjusting it's environment which coincidentally, tends to be filled with ions. Ions + coordinated patterns of charge propagation creates effective pumping infrastructure capable of creating overall fluid movement without the help of direct cardiovascular pressure, which can also facilitate the movement of non-charged molecules given sufficient ionic movement to disturb the neutral medium. However, this coordinated firing pattern to create overall ion flow isn't "information encoding to the cognitive process at hand" per se. It's just a bunch of cells getting fluid to move to get waste products to another location to get handled. None of those "knows" anything more than it's immediate environs, but based on things like quorum signalling in biofilms, it isn't outside the realm of possibility, that neural tissue has a completely chemically mediated process by which it knows "gradient blah can be shifted if everyone around me fires", and that given sufficient time and scope, you get an emergent quorum signalling based metabolic progress that selectively induces "coordinated garbage" from the information processing point of view, but very much not biologically/physically garbage point of view, in that that firing pattern clears the chalkboard so to speak for further processing. So to answer your question: why do nerves seemingly need to stop what we want them to do (full time cogitation as directed by an emergent consciousness that their physical processes collectively facilitates)? The answer comes down to homeostatic maintenance, and work the tissue has to do because that's how it evolved. You use the same bunch of neurons, they fill the immediate space with metabolic waste products which makes further firing or usage more difficult until the waste products can be cleared. How do you clear them? Stop doing what you're doing & ion pumpas a group. Coordinated ion pumping isn't driving the pattern recognition/consciousness engine in ways that make any sense, it's just cycling fluid to refresh the operating environment to restore the substrate for unburdened cognition again. Eukaryotic organisms are hard, maddeningly complex, and contain an astonishing amount of detail for something that for whatever reason, usually just seems to work. Could write volumes on these things for how deep the rabbit holes go.
hlynurd 2mo ago
>the Hadza uniformly reported high satisfaction with their sleep. And why wouldn't they? This is (presumably) the only kind of sleep they know.
- oulipo 2mo ago
  Well probably us modern human only know the "8h sleep at night" kind of sleep, yet a lot of people would tell you whether they're satisfied or not with their sleep
  - voidUpdate 2mo ago
    I mean I can vary from 9 to 3 hours of sleep a night, and I can tell you I'd rather get 9 than 3. Just because I'm meant to get 8 hours a night doesn't mean I do
- rob74 2mo ago
  They're probably also less confronted with articles/videos/social media posts telling them they're doing it wrong and how they should sleep instead. Sometimes ignorance (or rather, not overthinking things) is bliss...
- bialpio 2mo ago
  Do you really need to know other kinds of sleep in order to know if you feel like shit after waking up or if you feel fine?
  - hlynurd 2mo ago
    If they have no frame of reference then it seems like their general contentedness is being measured (or as another commenter indicated, their willingness to gripe.)
  - IAmBroom 2mo ago
    Yes. Even in your example, you propose an individual could know multiple kinds of after-sleep feelings.
  - 2mo ago
syllogism 2mo ago
This interview feels weird to me, maybe because there's lots of places where I'm thinking there's an obvious idea that isn't raised. Like, it seems obvious to me that sleep has a higher opportunity cost in humans than most other animals. So naturally there's more evolutionary pressure in humans to sleep more efficiently. Is this actually true? Dunno! But it was really weird that it doesn't get brought up.
usernametaken29 2mo ago
> untangle what he calls the sleep paradox: Sleep is critical to human functioning, and yet, we sleep fewer total hours than any other ape Instead of going to Tanzania you could’ve asked a sleep scientist. Sleep length has no known correlation to brain size and is known for drastic within family variation. What’s more sleep has a high within species variation too, some sleepers can survive 4 hours, others need 8. Collectively we used to sleep 9 hours in the 20th century, but it appears shorter sleep is fine too. TLDR: no one has any idea why sleep length varies and he won’t find his answers in antrophological studies in Tanzania, though luck, buddy
- sd9 2mo ago
  How do you think sleep scientists got their data in the first place? Some of them went to Tanzania.
  - IAmBroom 2mo ago
    Cite.
hastily3114 2mo ago
>“No way. They’re partying all night.” But they can, because there’s no top-down pressure to go into the office at 8 a.m. They’re free to catch supplemental sleep as needed throughout the 24-hour period. This feels like the key point to me. These societies follow their body and go to sleep when they are tried, while us in the west have to sleep at a specific time to fit our schedules.
- mywacaday 2mo ago
  A single block of sleep is a relatively new behaviour, I suspect partially driven by the availability of cheap sources of light and heat. https://www.bbc.com/future/article/20220107-the-lost-medieval-habit-of-biphasic-sleep https://www.bbc.com/future/article/20220107-the-lost-medieva...
  - bopou 2mo ago
    This is a contentious theory with little actual historical backing. Most likely people have been sleeping in one block since forever.
    - scotty79 2mo ago
      > Most likely people have been sleeping in one block since forever. Does that have stronger historical backing?
      - j16sdiz 2mo ago
        It is more common in high-latitude countries. Very uncommon in lower latitude.
        IAmBroom 2mo ago
        Another unbacked claim.
        jnfnfkfkt 2mo ago
        [dead]
tempfile 2mo ago
The article title is "Where human sleep went wrong" but then the entire article is about how we sleep the best we ever have, we have the most high quality sleep, and all the fearmongering about sleep is basically wrong.
i_love_limes 2mo ago
I think people in HN (and in general) have to remember the central axes of evolution before digesting this kind of article. I've already seen comments like it's "odd that no species has ended up evolving a continuous maintenance system" and "sleep has a higher opportunity cost in humans" in this comments section. This is a common, but poor framing of evolution. Remember: the only real rule with evolution is "did this evolutionary change mean they survived / reproduced more"? Evolution is not a local or global maxima solving function. I find this kind of attempt at interpreting selection common with engineers, programmers, etc.
- yuretz 2mo ago
  I can see why it isn't a local or global maxima solving function, but it surely can be modelled by one, right?
  - teekert 2mo ago
    I'm a biologist so forgive me the poor wording, but there are "infinitely high" peaks/walls in the evolutionary landscape, as in: "the human urinary system has some evolutionary constraints and anatomical features that are not optimally designed from an engineering perspective, but they are generally functional and reflect our evolutionary history rather than deliberate design." <- this is from AI, I didn't remember the details, but the ureters or urethra take a long way around the inner part of the body because at some point it was a good route, but as we evolved it became suboptimal, but we can't just evolve to untangle all the pipes in our body and do some cable management... We're stuck with what we have (no tunneling electrons ;)). So in that sense, a global maxima (minima?) solving function will probably not arrive at what we have, it has to take into account our evolutionary path, in its entirety (as in the whole tree.), because it is all encoded in 1 (or several) long molecules, and a radical changes would take a rewrite of many parts at the same time, which just does not happen. Maybe at some point we can do it ourselves... though I imagine there being a lot of unintended consequences in other places in the body :). Another example is that sometimes complexity in a cell signalling cascade is simply there to get some timing right (ie delay some response), and the complexity is just there, and won't simplify by itself -> But then later the complexity may start to serve some purpose. Just like proteins that are "copypasta-ed" in the genome, leaving one copy free to mutate and attain a function, or not... etc etc.
YLYvYkHeB2NRNT 2mo ago
A nap is the same as sleep, but we don't do this. Any correlation to our southern american friends and their siestas?
- giov4 2mo ago
  I tried to imitate japanese people in the public transport when i was there, meaning I managed to kinda sleep/nap with eyes closed for 10-15minutes between rides and it was astonishing. while I understand might be a more known thing, it was surprising to try it and feel very rested after that. I'm still surprised and I wonder why not the whole world does it. of course without the music at the stops would not be possible :P
  - vinyl7 2mo ago
    Growing the GDP and Shareholder Value is more important!
duskdozer 2mo ago
>18 degrees Celsius is considered optimal for sleep depth I'm instantly skeptical of anyone making universal statements like this, because they're certainly not true for everyone, and having looked into these and similar (f/x "ideal room/office temperature"), are based on many entangled assumptions. Most of the time I expect it's just people making after-the-fact justification for doing (or imposing) what they most prefer.
- deleted 2mo ago
  [deleted]
- ViktorRay 2mo ago
  When statements like this are made usually it’s because studies would have been done comparing sleep depth at different temperatures and there would have been a statistically significant increase in sleep depth at 18 degrees Celsius in the tested group compared to groups sleeping at other temperatures. I have no idea if that was actually done here but that’s usually how these statements are justified. Of course we are all individuals so it may not apply to everyone but you can say that for everything in medicine. Only thing we can do is look for statistically significant differences between groups in double blind controlled studies after controlling for all other factors.
  - giov4 2mo ago
    yeah probably lot of study measurements and data confirming that, I'm not skeptical about it, to me it feels like something scientifically measured proven since quite some time already. of course genetics and outliers still need to be considered. also do you know that the body temperature decreases during sleep? based on that I simply deduce and assume the more the difference between body and room temperature the more side effects arises for sleep, of course simplifying without ignoring all the rest.
  - IAmBroom 2mo ago
    And every time I hear about an optimum, I think of the Bathtub Curve. As I imagine the curve, I use a real bathtub. Where is the water deepest? At the drain, which is typically just under the faucet. Where is the optimal place to sit? Well, pretty much anywhere except there, because "deepest" (an optimum) isn't enough to accurately gauge "best place". But even if you can swing the faucet out of the way... where is the optimal place? Anywhere on the bottom, a broad, slow curve, as opposed to the steep walls or rim. So, if 18 degrees C is the optimum, what's the standard deviation? I bet it's not 0.1 degrees. Could be 2 degrees - and that would mean concentrating on 18 degrees is a distraction, not a goal. This is something evolutionary discussions don't address well, either. If a gene line (species) has a pressure to change, it can "settle" for any place on the bathtub floor (when the solution is shaped like that). This is another example of evolution not seeking an optimum; merely avoiding a pessimum (a word I just googled, and like!). In fact, it doesn't even matter if it's a bathtub curve. Maybe it's a slope, like the amount of capsaicin a pepper plant carries to fight off fungus. More better - but it costs something to make, so just make enough to ensure survival. More fungus? Increase capsaicin production. There's no floor to this bathtub; it's a linear slant all the way down to maximum possible capsaicin content (which, amazingly, is about 10% by weight of the fruit cells!!!).
mark_something 2mo ago
> Most importantly, when we measured their circadian function directly, small-scale communities had much higher amplitude circadian rhythms than global north populations, which I think is why they report being happy with their sleep even though it’s more fragmented. This could explain why I feel more rested when I wake up if I take glycine before going to bed, even though I don't sleep more.
fhn 2mo ago
"we’re the shortest sleeping primates, yet we pack in the most REM sleep relative to this short duration." Nothing surprising here. We sleep in cozy comfortable beds in a locked and secure location. Of course we'd can get int REM sleep. Compare to other primates who sleep outside with the critters and predators, deep sleep could mean the end of them.
- samtheDamned 2mo ago
  My understanding is that REM isn't particularly deep. Quick web searches aren't actually defining it as more like light or deep sleep, but many of our systems are more active than other stages[1][2]. Still I don't think it's super surprising that we spend more time in REM since our brains are uniquely complex and we spend a lot of energy on perception and interpretation, which REM seems to help with [1][3]. And I would be willing to be safety and comfort also play a decent role in it as well! 1: https://www.healthline.com/health/how-much-deep-sleep-do-you-need#waking-up-tired https://www.healthline.com/health/how-much-deep-sleep-do-you... 2: https://www.health.harvard.edu/healthy-aging-and-longevity/rem-sleep-what-is-it-why-is-it-important-and-how-can-you-get-more-of-it https://www.health.harvard.edu/healthy-aging-and-longevity/r... 3: https://www.sleepfoundation.org/stages-of-sleep/rem-sleep https://www.sleepfoundation.org/stages-of-sleep/rem-sleep
- fuzzfactor 2mo ago
  Probably the only primates where a significant portion spent tens of thousands of years isolated up in the Arctic during prehistoric times. Where the sun doesn't go down every single day anyhow, and you may need to trudge across the tundra routinely for more than 24 hours at a stretch to get almost anywhere, without ever worrying about it at all. Then they later came down and intermixed with (not) everyone else, so you never know who is going to be less tired than "normal" when they work a 36-hour day.
MrPFT 2mo ago
[flagged]

130 points by XzetaU8 2mo ago

More fragmented sleep, with people talking in the night, etc. I guess that's different from the low, unnatural, rumbles of cars and aeroplanes the majority of people have to put up with.

Pearse 2mo ago
I actually find it easier to sleep with the sound of people talking around me, it's very comforting.
yard2010 2mo ago
I could only wish for low unnatural rumbles of cars. In 3rd world countries it's non stop horns and noisy motorbikes
- HappyPanacea 2mo ago
  Car horns gotta be up there as some of the worst inventions of the 20th century, noise pollution galore.
  - jbuhbjlnjbn 2mo ago
    It works when you have strict rules on the use of horns and people get peer pressured into adapting to the behavior of their surroundings.
abigdog 2mo ago
737s are fine its dog barking that gets me.

Flashtoo 2mo ago

> Some emerging research suggests Earth’s magnetism matters, as well. Being barefoot on the ground versus 30 stories high in a downtown skyscraper puts you in a completely different magnetic environment. Really? My instinctive reaction to this statement is that it's quackery. Would be very interested to see headlines appear about this if it's true.

eru 2mo ago
People already live in different altitudes, ie with vastly different amounts of rock between themselves and the bits of the earth that produce her magnetic field. So colour me skeptical of this claim as well. And while I like going barefoot for other reasons, I don't think it makes much of a difference to the magnetic fields.
- krige 2mo ago
  > People already live in different altitudes, ie with vastly different amounts of rock between themselves and the bits of the earth that produce her magnetic field. It's not really the same thing. Construction and especially the high content of charged metal (whether it's power conduits or plain old frame) may make a considerable difference.
  - dotancohen 2mo ago
    Do many people sleep in such tall buildings? Obviously they exist, but I can't think of any over-20 story residential building I've ever been in. Office space, sure, but not residential.
    - nkrisc 2mo ago
      The amount of people who would regularly sleep in such a building is a minuscule fraction of the world population.
    - eru 2mo ago
      See https://en.wikipedia.org/wiki/The_Pinnacle@Duxton https://en.wikipedia.org/wiki/The_Pinnacle@Duxton
      - dotancohen 2mo ago
        Yes, like I said, these things exist. But I ask do significant populations of humans reside in the upper floors of such structures?

moffkalast 2mo ago

> Sleep is critical to human functioning, and yet, we sleep fewer total hours than any other ape, and are still arguably the most evolutionarily successful of the primates > humans are weird outliers—we’re the shortest sleeping primates, yet we pack in the most REM sleep relative to this short duration Isn't that sort of the point? Sleep is a detrimental necessity and the more efficient an organism is in needing less of it, the more effective it can be because it simply has more time to get ahead of the others? It's still very odd that no species has ended up evolving a continuous maintenance system that can run while conscious, the benefits when hunting other animals that need sleep would be enormous, so there has to be significant evolutionary push for it. I suppose the single hemisphere sleep some marine mammals do is part of the way there, but it is at most a lazy workaround. Practically all other organs have evolved to run 24/7 for up to a century without a single break, what makes brains so universally different?

deleted 2mo ago
[deleted]
salawat 2mo ago
The fact they electrically signal via chemical analogs fuelled by immersion in nutrient bearing fluid that also accretes waste products, yet is kept separate from the primary loop of the cardiovascular system by the blood-brain barrier?
- dotancohen 2mo ago
  But why is that fundamentally different from the technobabble description of any other vital organ?
  - salawat 2mo ago
    Life has a surprising amount of detail, and if you're only curious enough to interact with the answer as 'technobabble', this does not speak well of your genuine curiosity on the subject. However, in general... Form is shaped by function. The liver/pancreas are designed to handle the production of detoxifying/neutralizing agents that may in and of themselves kill nearby tissue, resulting in the propensity for notable regenerative capabilities. Kidneys/intestines are high surface area to provide more room for the physical processes driving selective permeability to occur, as well as habitable spaces for beneficial microbial symbiotes that aid in digestion. Skeletal/smooth cardiac muscles are optimized for energy burning to facilitate movement. Tendons/cartilaginous membranes are optimized for lubricating joints/connective tissue purposes. Tissues like the thalamus and tonsils, are there for immunity modulation and detection. Neural tissue however is all about signal propagation, and creating shifting networks of continuity that encode information and patterns, the tissue itself is just the medium, and that medium requires some process to clean out or reset the gradients in the synaptic gap. Otherwise, electrical charges cannot be consistently conveyed as flows of ions, actuated by releases of neurotransmitters into the bridge of the synaptic gap. The other constraint unique to neural tissue as well is it isn't motile, or capable of physical movement. All it can do is carry charge by a process of chemically modulated action potential building, yet also needs to have a means to carry out adjusting it's environment which coincidentally, tends to be filled with ions. Ions + coordinated patterns of charge propagation creates effective pumping infrastructure capable of creating overall fluid movement without the help of direct cardiovascular pressure, which can also facilitate the movement of non-charged molecules given sufficient ionic movement to disturb the neutral medium. However, this coordinated firing pattern to create overall ion flow isn't "information encoding to the cognitive process at hand" per se. It's just a bunch of cells getting fluid to move to get waste products to another location to get handled. None of those "knows" anything more than it's immediate environs, but based on things like quorum signalling in biofilms, it isn't outside the realm of possibility, that neural tissue has a completely chemically mediated process by which it knows "gradient blah can be shifted if everyone around me fires", and that given sufficient time and scope, you get an emergent quorum signalling based metabolic progress that selectively induces "coordinated garbage" from the information processing point of view, but very much not biologically/physically garbage point of view, in that that firing pattern clears the chalkboard so to speak for further processing. So to answer your question: why do nerves seemingly need to stop what we want them to do (full time cogitation as directed by an emergent consciousness that their physical processes collectively facilitates)? The answer comes down to homeostatic maintenance, and work the tissue has to do because that's how it evolved. You use the same bunch of neurons, they fill the immediate space with metabolic waste products which makes further firing or usage more difficult until the waste products can be cleared. How do you clear them? Stop doing what you're doing & ion pumpas a group. Coordinated ion pumping isn't driving the pattern recognition/consciousness engine in ways that make any sense, it's just cycling fluid to refresh the operating environment to restore the substrate for unburdened cognition again. Eukaryotic organisms are hard, maddeningly complex, and contain an astonishing amount of detail for something that for whatever reason, usually just seems to work. Could write volumes on these things for how deep the rabbit holes go.

hlynurd 2mo ago

>the Hadza uniformly reported high satisfaction with their sleep. And why wouldn't they? This is (presumably) the only kind of sleep they know.

oulipo 2mo ago
Well probably us modern human only know the "8h sleep at night" kind of sleep, yet a lot of people would tell you whether they're satisfied or not with their sleep
- voidUpdate 2mo ago
  I mean I can vary from 9 to 3 hours of sleep a night, and I can tell you I'd rather get 9 than 3. Just because I'm meant to get 8 hours a night doesn't mean I do
rob74 2mo ago
They're probably also less confronted with articles/videos/social media posts telling them they're doing it wrong and how they should sleep instead. Sometimes ignorance (or rather, not overthinking things) is bliss...
bialpio 2mo ago
Do you really need to know other kinds of sleep in order to know if you feel like shit after waking up or if you feel fine?
- hlynurd 2mo ago
  If they have no frame of reference then it seems like their general contentedness is being measured (or as another commenter indicated, their willingness to gripe.)
- IAmBroom 2mo ago
  Yes. Even in your example, you propose an individual could know multiple kinds of after-sleep feelings.
- 2mo ago

syllogism 2mo ago

This interview feels weird to me, maybe because there's lots of places where I'm thinking there's an obvious idea that isn't raised. Like, it seems obvious to me that sleep has a higher opportunity cost in humans than most other animals. So naturally there's more evolutionary pressure in humans to sleep more efficiently. Is this actually true? Dunno! But it was really weird that it doesn't get brought up.

usernametaken29 2mo ago

> untangle what he calls the sleep paradox: Sleep is critical to human functioning, and yet, we sleep fewer total hours than any other ape Instead of going to Tanzania you could’ve asked a sleep scientist. Sleep length has no known correlation to brain size and is known for drastic within family variation. What’s more sleep has a high within species variation too, some sleepers can survive 4 hours, others need 8. Collectively we used to sleep 9 hours in the 20th century, but it appears shorter sleep is fine too. TLDR: no one has any idea why sleep length varies and he won’t find his answers in antrophological studies in Tanzania, though luck, buddy

sd9 2mo ago
How do you think sleep scientists got their data in the first place? Some of them went to Tanzania.
- IAmBroom 2mo ago
  Cite.

hastily3114 2mo ago

>“No way. They’re partying all night.” But they can, because there’s no top-down pressure to go into the office at 8 a.m. They’re free to catch supplemental sleep as needed throughout the 24-hour period. This feels like the key point to me. These societies follow their body and go to sleep when they are tried, while us in the west have to sleep at a specific time to fit our schedules.

mywacaday 2mo ago
A single block of sleep is a relatively new behaviour, I suspect partially driven by the availability of cheap sources of light and heat. https://www.bbc.com/future/article/20220107-the-lost-medieval-habit-of-biphasic-sleep https://www.bbc.com/future/article/20220107-the-lost-medieva...
- bopou 2mo ago
  This is a contentious theory with little actual historical backing. Most likely people have been sleeping in one block since forever.
  - scotty79 2mo ago
    > Most likely people have been sleeping in one block since forever. Does that have stronger historical backing?
    - j16sdiz 2mo ago
      It is more common in high-latitude countries. Very uncommon in lower latitude.
      - IAmBroom 2mo ago
        Another unbacked claim.
      - jnfnfkfkt 2mo ago
        [dead]

tempfile 2mo ago

The article title is "Where human sleep went wrong" but then the entire article is about how we sleep the best we ever have, we have the most high quality sleep, and all the fearmongering about sleep is basically wrong.

i_love_limes 2mo ago

I think people in HN (and in general) have to remember the central axes of evolution before digesting this kind of article. I've already seen comments like it's "odd that no species has ended up evolving a continuous maintenance system" and "sleep has a higher opportunity cost in humans" in this comments section. This is a common, but poor framing of evolution. Remember: the only real rule with evolution is "did this evolutionary change mean they survived / reproduced more"? Evolution is not a local or global maxima solving function. I find this kind of attempt at interpreting selection common with engineers, programmers, etc.

yuretz 2mo ago
I can see why it isn't a local or global maxima solving function, but it surely can be modelled by one, right?
- teekert 2mo ago
  I'm a biologist so forgive me the poor wording, but there are "infinitely high" peaks/walls in the evolutionary landscape, as in: "the human urinary system has some evolutionary constraints and anatomical features that are not optimally designed from an engineering perspective, but they are generally functional and reflect our evolutionary history rather than deliberate design." <- this is from AI, I didn't remember the details, but the ureters or urethra take a long way around the inner part of the body because at some point it was a good route, but as we evolved it became suboptimal, but we can't just evolve to untangle all the pipes in our body and do some cable management... We're stuck with what we have (no tunneling electrons ;)). So in that sense, a global maxima (minima?) solving function will probably not arrive at what we have, it has to take into account our evolutionary path, in its entirety (as in the whole tree.), because it is all encoded in 1 (or several) long molecules, and a radical changes would take a rewrite of many parts at the same time, which just does not happen. Maybe at some point we can do it ourselves... though I imagine there being a lot of unintended consequences in other places in the body :). Another example is that sometimes complexity in a cell signalling cascade is simply there to get some timing right (ie delay some response), and the complexity is just there, and won't simplify by itself -> But then later the complexity may start to serve some purpose. Just like proteins that are "copypasta-ed" in the genome, leaving one copy free to mutate and attain a function, or not... etc etc.

YLYvYkHeB2NRNT 2mo ago

A nap is the same as sleep, but we don't do this. Any correlation to our southern american friends and their siestas?

giov4 2mo ago
I tried to imitate japanese people in the public transport when i was there, meaning I managed to kinda sleep/nap with eyes closed for 10-15minutes between rides and it was astonishing. while I understand might be a more known thing, it was surprising to try it and feel very rested after that. I'm still surprised and I wonder why not the whole world does it. of course without the music at the stops would not be possible :P
- vinyl7 2mo ago
  Growing the GDP and Shareholder Value is more important!

duskdozer 2mo ago

>18 degrees Celsius is considered optimal for sleep depth I'm instantly skeptical of anyone making universal statements like this, because they're certainly not true for everyone, and having looked into these and similar (f/x "ideal room/office temperature"), are based on many entangled assumptions. Most of the time I expect it's just people making after-the-fact justification for doing (or imposing) what they most prefer.

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ViktorRay 2mo ago
When statements like this are made usually it’s because studies would have been done comparing sleep depth at different temperatures and there would have been a statistically significant increase in sleep depth at 18 degrees Celsius in the tested group compared to groups sleeping at other temperatures. I have no idea if that was actually done here but that’s usually how these statements are justified. Of course we are all individuals so it may not apply to everyone but you can say that for everything in medicine. Only thing we can do is look for statistically significant differences between groups in double blind controlled studies after controlling for all other factors.
- giov4 2mo ago
  yeah probably lot of study measurements and data confirming that, I'm not skeptical about it, to me it feels like something scientifically measured proven since quite some time already. of course genetics and outliers still need to be considered. also do you know that the body temperature decreases during sleep? based on that I simply deduce and assume the more the difference between body and room temperature the more side effects arises for sleep, of course simplifying without ignoring all the rest.
- IAmBroom 2mo ago
  And every time I hear about an optimum, I think of the Bathtub Curve. As I imagine the curve, I use a real bathtub. Where is the water deepest? At the drain, which is typically just under the faucet. Where is the optimal place to sit? Well, pretty much anywhere except there, because "deepest" (an optimum) isn't enough to accurately gauge "best place". But even if you can swing the faucet out of the way... where is the optimal place? Anywhere on the bottom, a broad, slow curve, as opposed to the steep walls or rim. So, if 18 degrees C is the optimum, what's the standard deviation? I bet it's not 0.1 degrees. Could be 2 degrees - and that would mean concentrating on 18 degrees is a distraction, not a goal. This is something evolutionary discussions don't address well, either. If a gene line (species) has a pressure to change, it can "settle" for any place on the bathtub floor (when the solution is shaped like that). This is another example of evolution not seeking an optimum; merely avoiding a pessimum (a word I just googled, and like!). In fact, it doesn't even matter if it's a bathtub curve. Maybe it's a slope, like the amount of capsaicin a pepper plant carries to fight off fungus. More better - but it costs something to make, so just make enough to ensure survival. More fungus? Increase capsaicin production. There's no floor to this bathtub; it's a linear slant all the way down to maximum possible capsaicin content (which, amazingly, is about 10% by weight of the fruit cells!!!).

mark_something 2mo ago

> Most importantly, when we measured their circadian function directly, small-scale communities had much higher amplitude circadian rhythms than global north populations, which I think is why they report being happy with their sleep even though it’s more fragmented. This could explain why I feel more rested when I wake up if I take glycine before going to bed, even though I don't sleep more.

fhn 2mo ago

"we’re the shortest sleeping primates, yet we pack in the most REM sleep relative to this short duration." Nothing surprising here. We sleep in cozy comfortable beds in a locked and secure location. Of course we'd can get int REM sleep. Compare to other primates who sleep outside with the critters and predators, deep sleep could mean the end of them.

samtheDamned 2mo ago
My understanding is that REM isn't particularly deep. Quick web searches aren't actually defining it as more like light or deep sleep, but many of our systems are more active than other stages[1][2]. Still I don't think it's super surprising that we spend more time in REM since our brains are uniquely complex and we spend a lot of energy on perception and interpretation, which REM seems to help with [1][3]. And I would be willing to be safety and comfort also play a decent role in it as well! 1: https://www.healthline.com/health/how-much-deep-sleep-do-you-need#waking-up-tired https://www.healthline.com/health/how-much-deep-sleep-do-you... 2: https://www.health.harvard.edu/healthy-aging-and-longevity/rem-sleep-what-is-it-why-is-it-important-and-how-can-you-get-more-of-it https://www.health.harvard.edu/healthy-aging-and-longevity/r... 3: https://www.sleepfoundation.org/stages-of-sleep/rem-sleep https://www.sleepfoundation.org/stages-of-sleep/rem-sleep
fuzzfactor 2mo ago
Probably the only primates where a significant portion spent tens of thousands of years isolated up in the Arctic during prehistoric times. Where the sun doesn't go down every single day anyhow, and you may need to trudge across the tundra routinely for more than 24 hours at a stretch to get almost anywhere, without ever worrying about it at all. Then they later came down and intermixed with (not) everyone else, so you never know who is going to be less tired than "normal" when they work a 36-hour day.

MrPFT 2mo ago

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