The internet says a million things about what to eat and what not to in case of acne. For instance:

 - Refrain from dairy products.
 - Refrain from food heavy in unsaturated fat.
 - Refrain from too much sweet.
 - Consume fresh food (raw fruits & vegetables) but no cabbage and cauliflower.
 - No Alcohol

and what not.

My question is:

Is there really any relation between food consumed and the occurrence of acne?