Diet has been shown to rarely be a cause of acne in and of itself, although a healthy diet rich in vegetables can help. For this reason I'm glad to hear you do this. With few exceptions where an individual is sensitive to a particular food, you just don't get it from greasy foods, chocolate, etc. as was once believed. It is usually hormonally caused and related to clogged pores.
Yes, acne can be a sign of other problems - particularly of the endocrine system. Some people have excess androgens and adult acne often responds to entirely different treatments than teenage acne. There are also varying types of acne. A dermatologist should be able to help you get a handle on this and find the best treatment which could consist of hormones, antibiotics, accutane, etc.
Best wishes. I know this is a very frustrating condition.
The answers in online forums are for information only and are not intended to substitute for medical advice and care. Please see your personal health care provider for further evaluation of your individual case.
Debbie Miller, RN