Everyone varies, some people stall with caffeine, some not. Some people stall with fake sugars, some not. This is something you have to find out yourself. As for health reason, I don't think there is too much wrong with drinking that much pop (I drink about one can a day) But I think water is the easiest for your body to deal with, I don't think carbonated water is as easy for your kidney/liver to deal with.

Heidi