this post was submitted on 06 May 2025
34 points (90.5% liked)

Ask Science

10470 readers
43 users here now

Ask a science question, get a science answer.


Community Rules


Rule 1: Be respectful and inclusive.Treat others with respect, and maintain a positive atmosphere.


Rule 2: No harassment, hate speech, bigotry, or trolling.Avoid any form of harassment, hate speech, bigotry, or offensive behavior.


Rule 3: Engage in constructive discussions.Contribute to meaningful and constructive discussions that enhance scientific understanding.


Rule 4: No AI-generated answers.Strictly prohibit the use of AI-generated answers. Providing answers generated by AI systems is not allowed and may result in a ban.


Rule 5: Follow guidelines and moderators' instructions.Adhere to community guidelines and comply with instructions given by moderators.


Rule 6: Use appropriate language and tone.Communicate using suitable language and maintain a professional and respectful tone.


Rule 7: Report violations.Report any violations of the community rules to the moderators for appropriate action.


Rule 8: Foster a continuous learning environment.Encourage a continuous learning environment where members can share knowledge and engage in scientific discussions.


Rule 9: Source required for answers.Provide credible sources for answers. Failure to include a source may result in the removal of the answer to ensure information reliability.


By adhering to these rules, we create a welcoming and informative environment where science-related questions receive accurate and credible answers. Thank you for your cooperation in making the Ask Science community a valuable resource for scientific knowledge.

We retain the discretion to modify the rules as we deem necessary.


founded 2 years ago
MODERATORS
 

(Note: I'm not talking about FFI, but healthy people.)

It's said that we need sleep because waste products, such as adenosine (which is a CNS depressant) build up in our brains while we're awake. When we sleep, the glymphatic system activates and flushes it out. Too much adenosine is known to cause a slower heart rate, the body temperature to decrease, immune system to weaken, hallucinations, and more.

I read about how a Chinese guy (in 2014 or 2012?) deliberately stayed awake for 11 nights with no sleep at all to watch the world cup, and he died. The articles said he died of sleep deprivation.

Here's the part which confuses me. I understand why too much of a CNS depressant waste product in your brain would be deadly, since it'd supress vital functions such as breathing, heart rate etc. I'm just wondering why it wouldn't make you automatically pass out and sleep, long before it got to that level as it's something which very gradually builds up in your brain the longer you're awake.

top 17 comments
sorted by: hot top controversial new old
[–] [email protected] 12 points 1 day ago (1 children)

I frequently have trouble sleeping. After a few days of little to no quality sleep, I become unable to fall asleep.

The best way I’ve been able to describe it like a car battery. It helps start the car and when the car drives it keeps the battery charged. But if the battery gets too low it can’t start the car to recharge.

It’s like the part of my brain that tells my body to go into sleep mode hasn’t been charged by getting sleep. I’m so tired I can’t think and I feel absolutely awful, but the sleep doesn’t come.

I have to take a sleep aid when that happens.

This is just anecdotal, but if it works like that for the people who died, it makes sense to me.

[–] [email protected] 6 points 1 day ago (1 children)

I struggle with much of the same and have found that taking melatonin regularly (as in at the same time every day) and working out within 2ish hours before bed helps a lot...when I can remember to keep to that schedule, at least. Did you know that adhd is annoying asf to live with? Because it is.

Anyway, it might not be the fix for you, but it might also be well worth the shot. Either way, good luck getting where you want to be!

[–] [email protected] 2 points 1 day ago (1 children)

I’m open to try it! I also have ADHD and remembering to take my medication is a challenge for me too.

Is it something that you have to take everyday to be effective or can you just take it as needed? I hate taking sleep aids like ZzzQuil.

[–] [email protected] 2 points 17 hours ago

You can take it as needed, and it is the same chemical your brain naturally makes to get itself tired so it doesn't feel anything like other sleep aids. I recommend taking it daily because, in my case at least, the pattern of it helps my body get back on its own regular schedule. I get used to getting sleepy around the same time every night, as long as I remember to keep to the process.

[–] [email protected] 23 points 1 day ago (1 children)

I think that most people would indeed "automatically pass out and sleep" long before 11 days went past, unless they used some strong drugs or stimuli designed to keep them awake. Source: I tried to see how long I could go without sleeping, no tricks just sheer force of will, when I was young and healthy. Slightly more than 90 hours.

[–] [email protected] 19 points 1 day ago (2 children)

My record when I was young and healthy was around 114 hours. Took an entire month to recover and I felt horrible. It’s highly likely I was micro sleeping during that though, as I was alternating between a MUD gaming marathon and grabbing food/using the bathroom. I seem to recall I paused for a short time to have a shower too.

Anyway, I highly recommend never staying awake for that long. At the end I was mildly hallucinatory. When I woke back up after a 16 hour nap, I had a massive hangover, despite no alcohol/caffeine/etc. before.

[–] [email protected] 1 points 16 hours ago
[–] [email protected] 10 points 1 day ago (1 children)

A big part of a hangover is horrible sleep due to the effects of alcohol!

[–] [email protected] 8 points 1 day ago (1 children)

In both cases, a big part of the discomfort is due to tissue dehydration.

[–] [email protected] 1 points 16 hours ago

So true. So many things feel off when I haven't had enough water!

[–] [email protected] 2 points 1 day ago
[–] [email protected] 6 points 1 day ago

Adenosine can be blocked from uptake at receptors by something as common as caffeine, for example. I think when the point is reached that adenosine can be taken up again, there is so much extra to absorb that it overwhelms the body. This is supported by reports of people sleeping for high numbers of hours hours once they do fall asleep. Given that it can also lower heart and respiration rates, it's possible that is what leads to death. An example is that adenosine is related during certain types of seizures, and can pull someone out of a seizure, but in high amounts will depress the respiration rate to the point of death

[–] [email protected] 9 points 1 day ago (1 children)

Your body and brain do try to shut down, but the supposed reason we can control it is that being able to would improve survival when endurance hunting, or escaping dangerous conditions.

To an extent, it does shut down, but only in microsleep, which may not even be perceptible, and won't prevent an eventual collapse.

[–] [email protected] 4 points 1 day ago* (last edited 1 day ago) (2 children)

If these waste products are CNS depressants, wouldn't they cause you to pass out and sleep (similar to how people often pass out and sleep a couple hours after taking an ambien, for instance. Ambien is also a CNS depressant) before death happens?

Sort of like how your body prevents you from dying from holding your own breath by forcing you to breathe again once passed out.

[–] [email protected] 2 points 1 day ago

I can actually imagine that evolutionary pressure could favour being able to kill yourself from sleep deprivation. Our ability to deny ourselves sleep is of course a result of evolutionary pressure, where people that were able to keep going for days on end without sleep to survive a crisis outcompeted those that collapsed from sleep deprivation and passed out.

If we extrapolate to even worse crises, I can imagine that those who were able to keep going while carrying or protecting their kids or family until they died could have an edge over those that passed out from sleep deprivation, and died due to whatever they were staying awake to survive from. In short, that there are situations where it can be advantageous (from an evolutionary perspective) to be able to push yourself to the point of death, while ensuring that your kids survive.

I have no research to back this up, but I can imagine that humans could have evolved the capability to kill ourselves from sleep deprivation.

Another possibility (that's kind-of mentioned by others here) is that once you go past a certain point of sleep deprivation, the parts of your brain responsible for making you sleep essentially stop working properly. If we assume that historically, it was extremely rare that people got to that point, there would be very low evolutionary pressure to fix that issue (i.e. make us pass out before dying). In that case, this could be one of the many situations where we have an attribute not because it's advantageous, but because it's not disadvantageous enough to be selected away by evolution.

[–] [email protected] 4 points 1 day ago

I mean, that's what I just answered.

Were evolved to be able to resist it until it gets bad enough we just drop and die. Drugs like that bypass that ability because they're just a ton stronger, and in larger amounts

[–] [email protected] 1 points 1 day ago

I read about such experiments some time ago. If I remember correctly, after being forced awake for some time, some people stopped being tired and had to be forced to sleep. I also believe there are individual differences, so while some people in the discussion describe their own interesting experience, keep in mind that others might react differently.