I'm curious if anyone here knows if there is a consistent reason for us to avoid coffee, either because of i) some biology or metabolic pathway or ii) many people's experience using it, though people who have no problems are less likely to raise the issue. About a year ago I tried quitting coffee entirely for a week, expecting to feel better overall but without the temporary lift. Result: I felt about the same overall (cr-p!), but didn't have the brief window of better functioning coffee gave me. Or the taste, good coffee is way better than typical restaurant swill. That was enough experimenting at the time, so I decided to take it up again. I'm aware that too much will make me more exhausted and that the lift function doesn't always work. It's not magic. Now I'm taking another look. Is there more going on with it than I'm aware of? Is it placing a burden on some system that isn't immediately obvious? The most knowledgable-seeming person in my local CFS meetup advises avoiding it altogether, regular or decaf. My doc doesn't have an opinion either way. There are times when it's a lifeline, so I don't want to give it up to just be stylish. OTOH, it may be a subtle energy thief, in which case I would cut back, such alternating days on and off. Perhaps it could be doing something I'm totally oblivious to. Any personal experience or medical knowledge out there?