I raised the question about two years ago in "Thoughts On Caffeine" Why do we feel that years of overconsumption of caffeine will have zero consequences physically, mentally, or emotionally? As people like to point out to me, it's pretty hard to kill yourself with caffeine, but is that any kind of argument that it is harmless?
I've managed to stay away from caffeine for over a month now. No, it's not the first time I've "quit" caffeine, but I'm feeling pretty comfortable with my "fast" this time around. For the first two weeks, I had bouts of "thirst". Although I've never been a big liquor drinker, I imagine my experience to be something akin to (but probably much less severe than) the feeling of thirst that a recovering alcoholic might have.
The thirst has subsided and I've noticed several interesting things. Now, when I wake up in the morning, I am groggier because I sleep deeper even if I don't sleep as much. It takes me longer to get going but once I do, my body can sustain efforts longer. My highs are not as high and my lows are not as low. I am less tense during the day. I am feeling fatigue more, which is actually a good thing because it means I also notice "biofeedback" more acutely. I can actually feel what my body is trying to tell me about training effect and fatigue accumulation.