I am neither a medical doctor nor a PhD. I am a fellow acne sufferer who is good at science. Conventionally treatments work and don't work for scientific reasons.

Known contributers and/or aggravators to acne:
- Genetics
- Hormones
- Diet
- Stress
- Certain medications

Hormones include:
- Androgens especially DHT and DHEA
- Insulin
- Insulin-Like Growth Factor 1

Diet includes:
- High glycemicdiet
- Diary products

Medications include:
- Anabolic steroids

Things you can change other than getting conventional acne medications include:
- No diary.
- Low glycemic diet

A slightly non-conventional way to treat acne is medications that reduce the effects of DHT which is usually used by women due to it having less medical negatives to them but men may be desperate to try it.

Natural ways to lower androgens inculdes:
- Calorie restriction diet (lower several types of androgens)
- High protein low carbohydrates diet (specially for lower DHT)

Be warned that though a high protein diet when combined with low carbs lower DHT. High protein diets in general increase insulin-like growth factor 1. IGF-1 can be lowered by a low protein diet but a lower protein diet has not to my knowledge ever been proved by a study to reduce acne.