My understanding is that grapefruit, grapefruit juice, pomegranate and pomegranate juice should be avoided. I think lemons and other citrus is fine including tangerines and clementines.
Eating fruits that have edible skins I am wary of...fruit such as berries, apples etc as I am concerned that might be tainted, dirty or bruised in their natural state. No raw vegetables for the same reason. Good luck!