it's healthy for you and the only reason people gain back weight is because they think they can eat whatever they want to afterwards when in reality slimfast teaches you how to control calories and it does work and you get as much nutrients out of slimfast as you would out of vitamin pills becasue it doesn't stasy all in you if you have either but a lot does becasue i could feel the difference in my body when i was on it and now i'm off of it and i'm STILL LOSING WEIGHT becasue i actually learned from it...