I'm not too crazy about recommending a restrictive diet for acne patients but I always ask about protein shakes, whey, creatine and recommend a vegan powder if possible. Skim milk and low GLYCEMIC index diet if anyone is willing to change their behaviors.

For those motivated to make dietary changes, I recommend avoiding high-glycemic index food, dairy (especially skim milk), and red meat. I do recommend a Mediterranean diet enriched in vegetables, legumes, fish, as well as vitamin D and zinc.References:  Meixiong et al., PMID 35373155 Hasamoh ...

I definitely agree with the banning of all BUT plant-based protein shakes, especially whey protein. I do not tell my teen acne patients that they need a "low glycemic diet". I try to simplify and I tell them to cut down/out white bread, sugar, white potatoes and white rice and sweetened drinks. Pare...