Almost everyone experiences an occasional flare-up of acne, but it is most prevalent during adolescence, afflicting 85 percent of teenagers to some degree. Hormones are responsible for most cases of acne.Some people believe that eating foods like chocolate, French fries and other high-fat favourites can lead to acne or make it worse. Food does not cause acne, dermatologists stress, but eating a healthy, balanced diet is vitally important for great-looking skin.