Dont listen to doctors. Its all diet. I had horrible acne in early high school. Dermatologists put me on that shit and also retin-A (this was 8+ years ago). Turns out I was allergic to a few foods. I only figured it out with very careful and methodical analysis of food logs and self assessment of acne. About a month after I stopped eating chocolate and a few other things all my acne went away. I didn't eat the foods that caused the acne for a few years and now I can eat them with no ill effects. Thats a pretty strong indicator its diet / allergies.
Try it yourself. Worked for me, and for a few other people I talked to about it.
