Eh.  I drink only water and now tea, and I break out once a month like clockwork.  My diet is pretty close to scientifically perfect, too, saving my one day I go out to eat.  (It's actually lazier to eat well if you kinda get everything set up so it just happens...)  Good, bad (previously), there's been no difference.  Eating dorm food, zero-dairy, foreign cuisines...I just break out.  My family breaks out until menopause without treatment, but fortunately, it's not scarring or anything, and I can have zero zits when I treat it.