The obvious answer to that question is, never.
However, what I really mean by that is when do you stop drinking coffee during the day. This is all pretty much up to yourself and how you body handles caffeine. It seems like from talking to people that there are a few different variables that really do into this question, how much coffee you normally drink, your age and your own disposition to caffeine.
I was actually thinking about this last night as I was making my wife a chai latte on my espresso machine, it was about nine o'clock and that bag of Black Torpedo from AJ Coffee was really tempting, but I went without because I was unsure how having another double shot that night would affect my sleep. As I implied I had already had a latte a few hours earlier right after dinner, so I didn't want to chance anything.
For myself I drink a decent amount of coffee per day, probably along the lines of three cups in the morning then probably two double shots in the early evening or just one shot towards the end of the evening. So I believe this to be a pretty good portion of caffeine per day, and for the most part it doesn't have a huge impact on myself, or so I beleive. Combine this with the fact that I am still fairly young, a little more caffeine intake at night probably would not have had a huge impact on my sleep.
Although, I did over do the caffeine at night about a month ago so I have been wary to chance it ever since. I had three double shots in pretty close succession late in the evening and spent the first hour or so in bed that night just tossing a turning because I couldn't get my mind to settle down. This was pretty surprising to me because normally I can take a cup or two of coffee right before bed without any problems.
This kind of does circle back around to age, because I have heard many people say that they use to drink coffee at all hours of the day when they were younger, but as they aged their resistence to caffeine has dimished so it disturbs their sleep now.
So when do you guys stop drinking coffee? and for those of you with a few more years under you belt than I, how has your drinking habits evolved over the years?