That diet can affect acne and breakouts has been known for some time. It is becoming apparent that one of the issues which can cause acne breakouts are dairy products. This may not, however, be due to the actual fat content more that the breakouts are caused by the "bioactives" and hormones present in dairy products. Some suggestions for avoiding the hormones present include changing butter for coconut oil, cow's milk for almond milk (and almond milk yoghurt) and selecting vegan cheese products. In general terms, any foods which increase the blood glucose (aka sugar) level. (Also known as "high glycaemic" foods)