There is really nothing mysterious about remaining acne free. To put it simply you have to give your body what it needs and keep the stuff that it doesn't need away.
Acne prevention basically boils down to 3 steps/itemso Ensure proper digestion o Eat plenty of alkaline food o Maintain healthy colon flora
These 3 steps are by no means separate. Improving one of them also impacts positively the other ones - and vice versa.