001. at snopes.com, Alex Kasprak writes in "Bloods and Quips" (2016-12-09):
"in 1996, naturopathic doctor Peter D’Adamo published the book Eat Right For Your Type, which presented the hypothesis that diet, exercise, and lifestyle changes tailored to one’s blood type are an effective tool for weight loss, increased energy, and the reduction of myriad other ailments. This has popularly become known as the 'blood type diet', for which he is the primary proponent [...] in 1996, in the first edition of Eat Right For Your Type, D’Amato wrote: 'even now, as I write this, I am beginning the eighth year of a ten-year trial on reproductive cancers, using the Blood Type Diets. My results are encouraging. So far, the women in my trial have double the survival rate published by the American Cancer Society. By the time I release the results in another two years, I expect to make it scientifically demonstrable that the Blood Type Diet plays a role in cancer remission.' Such a study has yet to be released. On his website, D’Adamo has a section for scientific papers that support the science behind the diet. Nearly all of these self-authored papers are from the late 80s and early 90s, or are more recent blog posts written by D’Adamo. With the exception of that 2001 paper mentioned earlier, the only scientific papers he has published are either in the long defunct (but allegedly peer-reviewed) journal the Townsend Letter for Doctors (which frequently published studies on the efficacy of homeopathy), and the Journal of Naturopathic Medicine, which no longer exists and is not catalogued in any major scientific or medical journal index [...] D’Adamo is certainly prolific, both in his numerous blogs and in his library of best selling books. Lost within that sea of complex jargon, speculative observations, and anecdotal tales, however, is the fact that there is no widely accepted or peer-reviewed evidence that modifying one’s diet to match blood type has any effect on one's health";
a perpetual promise of 'science', without ever deliverying. Quite a ruse.