Do you know your blood type? You should. Thousands of years of evolution have split human blood into four basic “types”: A, B, O and AB. Each has a postive (+) and negative (-) (called “RH”) component as well. Roughly 43% of us are type O; 40% type A; 12% type B; and 5% type AB with interesting geographic, racial and ethnic differences in blood type and RH distribution.
While there is speculation that blood type predicts broad personality traits (especially in Japanese studies), there is strong indication that different blood types have different vulnerabilities — and do better with certain diets. A recent University of Pennsylvania study (April 2019) confirms that certain blood types are more prone to heart disease (see https://www.pennmedicine.org/updates/blogs/health-and-wellness/2019/april/blood-types ). Where one blood type does well on a meat diet, others might suffer.
Type O is the oldest blood type in the world with the most robust digestive system. Type O needs animal protein for good health. Has trouble with wheat and gluten. Thrives on vigorous workouts. Less prone to heart disease. O negative is a universal donor.
Type A has a more fragile digestive system which has trouble tolerating 4 legged protein. This blood type might do well as a vegetarian. Can be lactose intolerant and anemic. For this reason, iron and Vitamin B-12 supplements may be helpful.
Type B has difficulty with wheat and gluten though dairy is usually just fine. Chicken can cause health issues due to an agglutinating lectin which may adversely affect the circulatory system.
Type AB is the new kid on the block having been around for perhaps 1,000 years. Should avoid red meat especially smoked and cured meats as AB shares the low stomach acid of Type A and diminished stomach acid leaves one more prone to stomach cancer.
An interesting study of the respective vulnerabilities by blood type is found at https://www.gaia.com/article/7-relations-between-different-blood-types-health There are many articles on this topic. Just Google blood type and health