I used to drink -- no exaggeration -- gallons a day on average. I kept drinking them through induction, but shortly afterwards noticed mild cravings after drinking them, so I cut them out entirely. The cravings went away. The last couple of weeks I've been drinking them again (nowhere near as much as I used to drink, maybe a 20 oz bottle every few days), with no cravings, and in fact, if I have one as a sort of snack, I lose my appetite for the meal I'm supposed to eat.

In my case, I think it was psychological. Because I subconsciously associated drinking diet drinks with the prodigious overeating of my old lifestyle, I think when I drank them it brought back the cravings of that period. Once I sort of "broke" that association, it was OK for me to drink them again without stirring up cravings. Of course, it's best not to drink the stuff at all, as the only potential benefit of drinking them is a slight revving of the metabolism from caffeine, while on the downside, who knows what nasty things all those chemicals do to your body.