Food, Beverage & Supplements for Blood Type O

People with type O blood should have plenty of fish and vegetables, says the Blood Type diet creator.

People with type O blood should have plenty of fish and vegetables, says the Blood Type diet creator.

If you have type O blood, Blood Type diet creator Peter D'Adamo says you should eat differently from people with other blood types. D'Adamo, who detailed his blood type diet theory in "Eat Right For Your Type," claims type O people will be more likely to gain weight and develop thyroid disorders and ulcers unless they eat in a way that mirrors ancient hunter-gatherers. According to D'Adamo, people with type O blood are the direct descendants of these prehistoric people. You might lose weight following the Blood Type diet's guidelines for type O people, but respected health experts, including diet and fitness expert Dr. Melina Jampolis, caution that it may not be a good choice for everyone.


D'Adamo says that people with type O blood can eat plenty of fish, beef, lamb and vegetables like broccoli, lettuce, kale, onions, beets, garlic and red peppers, but should limit their intake of poultry, shellfish, many types of beans and legumes and many types of fruit and vegetables such as asparagus, mushrooms, carrots and cucumbers to one or two servings per week. Type O blood type individuals are advised to completely avoid all pork products, eggs, dairy products, peanuts, cabbage, potatoes, avocados, eggplant and most grain products, including any bread or pasta made from white or wheat flour. For cooking, D'Adamo says blood type O people can use olive or canola oils but should avoid corn or safflower oil.


People with type O blood shouldn't drink cow's milk, certain types of alcohol including beer or spirits and beverages containing caffeine like coffee or black tea, says D'Adamo. You're allowed to have water -- including mineral and soda water -- herbal teas like chamomile or green tea, red wine in moderation, juices prepared from allowed vegetables and fruits, especially black cherry, prune, pineapple, mango and guava juices. You may also drink soy or almond milk.


Blood Type dieters are instructed to take dietary supplements that will supposedly help them avoid developing medical conditions unique to people with their blood type. People with type O blood should take bladderwrack -- a form of kelp -- advises D'Adamo, to promote weight loss. They are also told to take deglycyrrhizinated licorice, or DGL, to prevent ulcers, and bismuth and mastic gum to deal with any stomach problems. Calcium, B vitamins and digestive enzymes are recommended for type O individuals, but they should avoid vitamin E and vitamin A which, allegedly, can interfere with their blood-clotting abilities.


Jampolis warns that the diet D’Adamo recommends for a person with type O blood is not balanced because it completely eliminates dairy products and grains like wheat. She also points out that the large amount of animal-based proteins included in the diet is not only expensive – D’Adamo says you should preferably purchase only organic, grass-fed meat and wild seafood – it may significantly increase your risk of cancer and heart disease. Mayo Clinic nutritionist Katherine Zeratsky agrees, saying that the Blood Type diet is not based on any scientific evidence. Do not begin any form of the Blood Type diet until you’ve spoken to your doctor about the possible dangers.

About the Author

Michelle Kerns writes for a variety of print and online publications and specializes in literature and science topics. She has served as a book columnist since 2008 and is a member of the National Book Critics Circle. Kerns studied English literature and neurology at UC Davis.

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