I have a mix on that. Because I did do diet drinks and lost weight, but I think there was a limit I did, not ALOT all day, and some of those diet sodas have some sodium in them which will help you retain water. I choose the diet rite...it has no cals, no sodium, no sugar...just complete zero. Almost like drinking water only in soda form. But I limit them too to 2 a day if I drink them. So, I have done both, but they were in different "forms" one with sodium, one without and the one without I have not done a "test" of drinking them all day to see if I would still lose weight. Guess I had that fear of what happened before on the other diet soda.