Star,
I was very invovled in the study of blood and blood factors when I was founder and President of the Rara Blood Club in St. Louis, Mo many years ago. There is much more variety contained in blood than just the usual A, B, AB, O RH positive and RH negative typing. "There are more than 20 genetically determined blood group systems known today, but the AB0 and Rh systems are the most important ones used for blood transfusions." Those who go on the blood type diet and have no additinal factors, antibodies, sub-types etc, it might work but how many of us have had our blood tested to that degree? Also, what type testing did the authors of the book do relative the the subcatgories in the various blood types? I would be very interested to see if there is a corralation in blood types, diseases, mortality and best types of chemo etc. if the blood type were factored in.