Food That is Not Good for the O Blood Type

Dairy products are off limits for people with type O blood on the Blood Type diet.
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A woman who has type O blood should follow a high-protein, low-carbohydrate diet that's heavy on beef, game meats, saltwater fish and vegetables, says Blood Type diet creator, Peter D'Adamo. According to D'Adamo, that's because type O people are the direct descendants of ancient hunters and gatherers. If you eat foods that weren't part of your ancestors' diet, you'll be more likely to develop ulcers, arthritis or thyroid problems, warns D'Adamo. Make sure you talk to your doctor before you start any form of the Blood Type diet. Experts like Dr. David L. Katz, the Yale-Griffin Prevention Research Center director, says that following the program -- especially for type O people -- could result in nutritional deficiencies.

Poultry and Pork

    D'Adamo says that if you have type O blood, you should strictly avoid all pork and pork products including ham or bacon. Catfish, lox, herring and goose are also on the forbidden list. You can have chicken, turkey, duck, rabbit and fish like shrimp, scallops or claims occasionally, but not more than twice a week. All meat should be organic and as lean as possible.

Dairy Products and Eggs

    All dairy products and eggs are restricted for type O people on the Blood Type diet. Rice milk can be substituted for cow's milk, when needed. If it's too difficult for you to eliminate all dairy from your diet, D'Adamo advises taking an enzyme supplement to help with digestion. Katz points out that the limitation on dairy products can end up leaving you without adequate calcium, which can increase your risk of osteoporosis.


    Nearly all types of grains are considered bad for people with type O blood on the Blood Type diet. You're advised to avoid all forms of wheat, corn, oats, bulgur, pumpernickel and semolina, as well as any products containing these as ingredients. Barley, quinoa, rye, buckwheat, spelt, amaranth and rice are acceptable a few times weekly. D'Adamo says that most grains are banned for type O people because they supposedly have inherited ancient antibodies that will react with the lectins in cereal grains like wheat, and that this will interfere with their insulin metabolism.

Beans, Nuts and Seeds

    Type O individuals are instructed to steer clear of red, navy and kidney beans, poppy seeds and nuts such as peanuts, Brazil nuts, cashews and pistachios. You're allowed to have sesame seeds, sunflower seeds, almonds, pecans, pine nuts, green peas and garbanzo, black and great northern beans up to two times a week.

Fruits and Vegetables

    D'Adamo recommends that a type O person should completely avoid potatoes, avocados, all types of cabbage, eggplant, corn, mushrooms, sprouts, olives, cauliflower, oranges, berries like strawberries or blackberries and melons such as honeydew or cantaloupe. Tomatoes, peppers, asparagus, beets, lettuce, squash, apples, bananas, pineapples, grapes, peaches, pears, lemons and limes aren't optimal for type O people, but are fine occasionally.

Oils and Seasonings

    As a type O person, you'll need to give up ketchup, pepper, vinegar, vanilla, nutmeg and cinnamon in order to follow the Blood Type diet. You should also avoid oils like corn, safflower and peanut oil. Canola and sesame oil can be used sparingly.


    Caffeine and alcohol aren't recommended for type O people, so soda, regular tea and coffee and all types of wine, beer and spirits are restricted on the Blood Type diet D'Adamo says caffeine is especially bad for those with type O blood because it raises your adrenaline level.

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