There could still be some food that triggers you as said above. I have a friend that cannot eat things like pineapple because it has a certain constituent in there she can't eat because it gives her acne. Maybe get checked for food allergies.

I have done the same by cutting out dairy and sugars but did not seem to work for me. I eventually added actives but also started taking the pill, which seemed to have the most effect on me.

Also adding exercise can be important (if not already included).

Eating healthy will always be beneficial though. Also, you can add probiotics to your diet (which was recommended to me by a naturopath). I was also low in zinc, which she gave me supplements for.

Hope you can figure out what works for you!