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by relyks 385 days ago
Basically, caffeine is bad for sleep (learning and recovery) if taken late enough and significant amounts remain in your system at bedtime. It does note that even having a coffee first thing in the morning does have a measurable effect on deep sleep brain waves. Fast metabolizers of caffeine might be different. Don't drink coffee in the afternoon is probably the take away for most people
4 comments

Old people love coffee late in the day.

Grandpa used to wake up at about 2 in the morning to pee, and would have a cup of coffee before going right back to sleep.

So maybe the effects nullify after a certain point?

I've never been able to fall asleep easily. When I see someone who instantly can, I wonder if they are chronically exhausted from a lifetime of bad sleep. I know it's probably not the case but it kind of makes me jealous.
I've become a lighter sleeper as I've gotten older, but generally fall asleep pretty quickly. I don't think it's from any chronic lack of sleep. It's mostly a matter of probably lucky genetics and also actually taking my sleep hygiene really seriously which very few people do. I:

* Try to stick closely to a regular sleep schedule.

* Keep my bedroom very dark and cool.

* Don't lay in bed and stare at a screen a lot. I try to build a mental association with my bed and sleep.

* Try to get some amount of physical exercise in the day and get out of the house. I find it's much harder to fall asleep if I didn't have a full-feeling day.

* Hydrate well throughout the day, but not right before sleep. (Not as much a problem when you're younger, but as I've gotten older, my bladder increasingly is the limiting factor for sleep length.)

* Pay attention to my anxiety. If I have thoughts keeping me up, I get up and write them down. That helps my brain feel like it doesn't have to stay alert and remember them.

> * Try to get some amount of physical exercise in the day and get out of the house. I find it's much harder to fall asleep if I didn't have a full-feeling day.

This is the most improtant point that works for me. It's simple: getting a bit tired makes it easier for me to fall asleep. And if I'm not and I feel like I'd like to explore the universe when it's time to go to bed, I get on my stationary bike and my brain finally relaxes.

I wonder too.

It doesn't say so on the DT page here:

https://en.wikipedia.org/wiki/Delirium_tremens

But I read something somewhere that alcohol does something that prevents REM or soemthing, and when you stop drinking your sleep-deprived body wants to make up the REM and will even do it while you're awake.

don't know for sure

EDIT: https://pmc.ncbi.nlm.nih.gov/articles/PMC2778757/

...supports early theories that the hallucinations of DTs represent an intrusion of REM sleep processes into the waking state (for a review, see Zarcone 1978).

It's a real rarity for me to drink, it's probably been 3+ years since I've had anything with alcohol. Cannabis did help me get to sleep (though can't say for certain that it was quality sleep since it killed my dreams), but it's probably been even longer since that (I was a very, very heavy user but quit for other reasons).
That he was able to go back to sleep with caffeine in his system doesn't show anything at all about the quality of that sleep.
Any my brother seems to function having a coffee only a couple of hours before bedtime since he was 18. If I do the same I'll not sleep at all and feel terrible the entire next day.

The question is more about would you function better in some way without that, and how much effects vary over the populace.

Caffeine in low doses doesn’t really seem to have any effect for me. Or at least not an acute noticeable effect. I drink coffee out of habit and because I like it. But if I’m on holidays and don’t have access to it, it doesn’t bother me in the slightest.
I’m the same way. Drink coffee daily because I like it for breakfast. And I love espresso with dessert after dinner. When I’m away I typically consume 0 caffeine for 1-2 weeks and have no noticeable downsides. If anything I get less sleep but am more active on vacation because I’m doing more.

I suspect I’m a fast metabolizer but no way to know really.

Old people drink decaf
Have ADHD. Caffeine slows my brain down and I can fall asleep directly after having consumed a half-pot of coffee.
Same here! If I really can't sleep a small sugar-free high-caffeine energy drink is as good as a sleeping pill.
This must be my diagnosis. I can smash 3 cups of coffee and conk out in 15 minutes.
caffeine seems to accumulate though, very soon it won't matter how late in the day you took your coffee today because there is still some amount in there from yesterday too. Personally I'm trying to drink as little coffee as possible now, sleep is too precious. I cannot risk having this constant negative health impact on my life.
I am a massive caffeine drinker. Like many of us, I monitor my sleep religiously so I have an anecdote. Late afternoon espresso or hot coffee is usually quite sleep effecting.

However - I have found that cold brew does not bother my sleep! At least the brand that I drink. Very strange, but awesome. Cold brew does not have the acidity of hot coffee which is a double bonus if you get acid reflux at night from poor eating or drinking habits. Give it a whirl.

I think it will wildly vary depending on how regular your life cycle is.

As an anecdote I also tried tracking my sleep, only to realize:

- consumer trackers are wildly inaccurate (best we can do is compare them to a "medical grade" reference tracker, which might be accurate or not, who knows)

- there was so many other things going on every day, pinning it down to even two or three factors was just impossible (e.g. I drink more coffee when I have more time to make it, which is related to my stress level and work volume etc.)

- watch data were a PITA to export and analyze separately. I did it twice or thrice and didn't bother after that.