Reading past comments I wonder about the breath of reading others have done on the medical issues described in William's fourth book.
Books that link themselves to many medical research reports tend to do so for support of their hypothesis only and discard any medical research reports that disprove their preferred hypothesis.
William's in contrast will disprove current medical trends and fads with a meta description of what is behind some complex medical issues without claiming the final word. There is more to understand yet specially in integrative medicine. In the meantime William's recommendations are useful for patients who are suffering today. The proof is always in the improvement of the patient's well being. William's does read all those books and medical research reports that are giving misdirected recommendations.
I for one have gained a better understanding on how to deal with my diabetes 2 condition. William's diet recommendations run counter to many current diet fads, and they are helping me.