Well, if I have coffee after midday, I am sleepless for the night. But, I love my morning coffee, which helps me get thru the day with the students. If I have even a cola after 3 pm I'm up for the night.

At times, I've tried to wean myself from caffeine. When I've resorted to this, it was because my anxiety level seemed so high, and it WAS beneficial. I should probablly abstain from coffee entirely, but I love it in the morning.
Patty