Your Diet: Type Os (considered the original blood type) are descendants from hunter-gatherers who relied mainly on animal protein to survive their strenuous lifestyles.
What to Eat: Eat lean beef, lamb, turkey, chicken or fish (like bass, cod, halibut, sole and rainbow trout), kelp, seafood and (in moderation) salt, which lowers your levels of iodine, giving you optimal thyroid function.
What to Avoid: You might have difficulty digesting dairy, eggs and gluten, and should avoid wheat germ and wheat products like bread. Beans and legumes should also be avoided when possible, since they mess with your digestion and can wear you out or make you retain fluids. Cruciferous veggies like cabbage, Brussels sprouts, cauliflower and mustard greens should be nixed because they inhibit thyroid function.
Your Workout: It’s especially important for you to work out regularly to stay fit, and exercising will help regulate stomach problems and ulcers you may experience because of your O-ness. Which is fine, since your blood type thrives on physical exercise anyway. Get sweating with the treadmill, swimming, running, cycling and weight training.