It is informative about other needs for mineral (zinc) absorption like essential fatty acids etc. among many other things.
Be sure to only use things like real organic butter, coconut oil and give him some cod liver oil (lemon flavored may be good) for the vitamin A, E, D and Essential Omega 3 Fatty Acids; or fish oil if he tends to get plenty of sun
Let him get out side to play and work in the dirt... also great and healing, not only for him but for all of us.