Every time I've successfully lost significant weight, I was drinking mostly water and not diet sodas. I half-way wonder if our bodies release insulin into the bloodstream in part due to the presence of a sweet taste on the tongue -- even if noncaloric. Because anecdotally, I think I get hungrier faster after a Diet Coke.
I'd wager regularly consuming sweetened things also makes it a lot harder to quit sweetened things and get rid of the "sugar craving" reported by many.
