Here is what Steiner has to say on milk:
"Among oriental peoples there is a certain way of practicing the art of healing in which the doctors attach the greatest importance to the nourishing of their own physical body. (78) In places where the old spiritual life still exists, there are those who have become healers by following a diet consisting exclusively of milk. They are quite clear that because they exclude everything else they gain certain healing forces within themselves, especially in the treatment of so-called mental illnesses. They have their special methods. They know for certain that when they only take milk they then develop quite definite forces."