A good supply of vitamins helps a lot with acne.
Especially Vitamin B5, Pantothenic Acid ESPECIALLY. Ever since I started taking a supplement of just that, I saw really great results. I had a problem with acne on my face, on triceps, shoulders and upper back, and most all of it has cleared up.
Acne can be a combination of a lot of things, so do your research, but I definitely suggest B5, it helps A Lot, especially if you are on a cycle, it helps with reducing oils surfacing to the skin that can cause acne.
Good Luck!