Please do post about it when you have the data! I hope your Grandfather will consent to act on this..
Ref Arthritis also:
There are a couple of inexpensive paperback books authored by Dr. Deforrest C. Jarvis, MD, entitled "Folk Medicine" and "Arthritis and Folk Medicine" which I think you will find invaluable for your Grandfather. Dr. Jarvis made intensive use of Honey, ACV, and Kelp for his many successes with arthritics.
BTW, nothing you glean from Dr. Jarvis' books will be in conflict with anything Moreless has said here.