According to Dr. Peter DÁdamo, author of "Eat Right For Your Type", a chemical reaction occurs between your blood and the foods you eat, and so it is good for our health if we choose a diet that matches our blood types.
Blood Type O
Your diet profile should be high protein. You are the meat eaters. You should eat plenty of meat, fish, vegetables, and fruit. Try to lessen your intake of grains, beans, and legumes. And if you want to put on some weight, you should include kelp, seafood, salt, liver, red meat, kale, spinach, and broccoli in your diet. For weight loss, avoid eating wheat, corn, kidney beans, navy beans, lentils, cabbage, Brussels sprouts, cauliflower, and mustard greens.
Blood Type A
If you have this blood type, it is best that you become a vegetarian. Never fail to eat vegetables, tofu, seafood, grains, beans, legumes, and fruit. Meat, dairy products, kidney beans, lima beans and wheat help you gain weight while vegetable oil, soy foods, vegetables, and pineapple help you loose some pounds.
Blood Type B
You should be the balanced omnivore. You should include meat(no chicken), dairy, grains, beans, legumes, vegetables, and fruit. If you want to gain weight, include corn, lentil, peanuts, sesame, seeds, buckwheat, and wheat in your diet. Greens, eggs, venison, liver, licorice, and tea aids you in loosing weight.
Blood Type AB
You should have a mixed diet in moderation. Include meat, seafood, dairy, tofu, beans, legumes, grains, vegetables, and fruits in your diet. Red meat, kidney beans, lima beans, seeds, corn, and buckwheat help you gain wheat while tofu, seafood, dairy, greens, kelp, and pineapple help you loose weight.