Why does coffee help me sleep better?

[Inigo Montoya]

Because it shouldn't, right?

I usually drink a 44 oz "cup" of coffee every day between 8:am and noon. I rarely take any other caffeine. But at certain times of the year I have a lot of trouble with insomnia. A double espresso shot fixes the problem. Espresso about 30 minutes before bedtime and I sleep like a baby from 10-6. No coffee? Fitful, broken sleep for about 4 hours before I just get frustrated and climb out of bed.

I'm an unmedicated bipolar guy, if that matters.

[Glazer]

Without googling the exact amounts, 44ozs. is one large dose of caffeine. Caffeine is habit forming and you have been taking large doses for awhile. The most probable reason you can't sleep is you are going through withdrawal, once you feed the need you can relax and go to sleep. You might want to think about rehab.

[Hatshepsut]

I like Glazer's theory, but another possibility is simply that you have an idiosyncratic reaction to coffee. I know I do, or at least did. For years I could quaff coffee all day with no noticeable stimulation resulting, and no effect on my sleep at night. I could also go "cold turkey" without feeling any withdrawal symptoms. I think this is all still true but I'm not positive, as my sleep is so poor that I've long since stopped consuming caffeine after about 10 am because I don't want to do anything that could possibly contribute to insomnia. But maybe I should take your story to heart and try a double shot of espresso at bedtime some night to see if it helps me sleep!

(This is not to say I didn't have any reaction to caffeine at all - like many people, I found it helpful for migraines.)

[Revs]

I like to drink coffee before I go to sleep, it makes me dream faster.

[AllWalker]

Though I don't think this is what's happening in this case, something that happens with me is that because caffeine is dehydrating, if I haven't been keeping my fluids up it makes me sleepy.

[Revs]

Plus sometimes when the caffeine wears off you feel like you are hitting a wall. Once you are at that point then it's sleepy time.

[tunaman]

Well, caffeine doesn't seem to affect me at all. I can drink a can of Mountain Dew and drift off to sleep with no problems. If some of my friends did that, they'd be up for days.