I am a caffiene junky. I drink a pot of coffee black every morning. Then I drink plain unsweetened ice tea all day. I can drink coffee 15 mins before bed and sleep like a baby. I gave up my smoke 10 years ago, I am trying to loose my fat now. I cant get rid of caffiene at the same time. I seem to still be loosing just great. It can cause more cravings for other things, its a stimulant, its causes water loss.