I have just been through a rough period where i have been eating anything at anytime. Result: My acne became really severe and inflamed.
In the weekend I decided to eat more healthy and acne friendly (no dairy, low gl). Result: In just a couple of days active acne has dried up and hardly any new pimples and cysts are formed.
It does not have to take a long time for things to clear up. So satisfying to see my efforts are worthwhile. It can be really simple. Nice to remember when things get confusing and tough!