I was talking to a doctor friend, explaining how eating lower carb and lower calorie seemed to be helping my acne, and when he said that past research didn't back that up, I went searching for evidence. On my search I found this fascinating article from Dermato-endocrinology (German journal) that seems to explain why eating lower carb helps some people with acne; why milk and dairy harm some people; and why eating too much protein harms others. Really, it was saying that the Western diet throws all these factors together to mess people up, and gives a pathway to explain it. I'm not pretending to have understood even 1/3 of it, but figured some people on this forum might understand it, and might find it of use.

The entire article is free, here:

Dietary intervention in acne
Dietary intervention in acne
Attenuation of increased mTORC1 signaling promoted by Western diet

From the abstract:
"Epidemic acne has to be recognized as an mTORC1-driven disease of civilization like obesity, type 2 diabetes, cancer and neurodegenerative diseases. These new insights into Western diet-mediated mTORC1-hyperactivity provide a rational basis for dietary intervention in acne by attenuating mTORC1 signaling by reducing (1) total energy intake, (2) hyperglycemic carbohydrates, (3) insulinotropic dairy proteins and (4) leucine-rich meat and dairy proteins. The necessary dietary changes are opposed to the evolution of industrialized food and fast food distribution of Westernized countries. An attenuation of mTORC1 signaling is only possible by increasing the consumption of vegetables and fruit, the major components of vegan or Paleolithic diets."

Among the remarks in the conclusion:
"Paleolithic diet regimens come close to the goal of attenuated mTORC1 signaling but have to consider that unlimited total protein intake may overstimulate leucine-mediated mTORC1 activation."

Sadly, I think I'm going to have to re-eject most cheese from my diet. Oh well. I'd rather have a clear complexion than a slice of cheese.