This is How Your Blood Type Affects Your Diet Plus What To Eat To Help It

By Khyber Oser

Fad diets come and go as assuredly as the seasons. But when a nutritional approach persists for more than several years, chances are it has dietary merit—or, at the very least, warrants a little investigating.

The Blood Type Diet (BTD) debuted in 1996 in the book by Peter J. D’Adamo, ND, Eat Right 4 Your Type: The Individualized Diet Solution for Staying Healthy, Living Longer & Achieving Your Ideal Weight (Putnam, 1996). Fourteen years later, the title is still one of the best-selling diet books on Amazon. But can a nutritional approach based on ABO blood designation work?

My story

Growing up, I was the no-meat kid. While my schoolmates devoured hamburgers and hot dogs, I grazed on tofu stir-fries and whole-wheat PB&J sandwiches. I loved being vegetarian. My diet, not to mention my funny first name (hippie parents), was a defining part of what made me different and special, what made me me.

As I got older, eschewing meat went from a fact of life to an act of conscience. I turned vegan in college, cutting out eggs and dairy to subsist on grains, beans, nuts, seeds, oils, and fresh produce. Although my heart and mind felt great, my body was not as happy. Acute issues, like an aggressive hand rash and debilitating hip pain, now joined my chronic chorus of congestion, dry skin, and dandruff. The eczematous little pimples bubbling up between my fingers itched so furiously that, along with my bothersome hip, I couldn’t sleep through the night.

So began my medical quest. Two dermatologists briskly diagnosed contact dermatitis and prescribed steroid creams. But I didn’t like their catch-all terms or Band-Aid solutions; instead, I wanted to find out why I was jumping out of my skin, literally.

Next, a naturopath told me I had candida—an overgrowth of fungus in the intestines—and advised me to avoid sugary, yeasty, pickled, and fermented foods. I eventually gave up that regimen, though, after I’d so sensitized my body to the point that a measly slice of cake made me violently ill.

Finally, I contacted Gina T. Ogorzaly, DC, a chiropractor and cofounder of the Diamondback Wellness Center in Albuquerque, New Mexico. At our first meeting, she asked me my blood type.

“O positive,” I said, somewhat confused. “Why do you ask?”

She nodded and hmm’d knowingly. She riffled through her filing cabinet and handed me O-specific eating charts that broke down foods into three categories: highly beneficial, neutral, and avoid.

“Restrict yourself as much as possible to red meat and vegetables,” Ogorzaly said. “Stay away from grains, especially wheat. You’re Type O. You’re a hunter.”

My jaw almost hit the chiropractic table. Red meat? Hunter? Me? I bristled at the notion that, based on blood type alone, I was predestined to be an obligatory meat eater. And anyway, even if Ogorzaly was right, so what? Wouldn’t I rather suffer than throw away my hard-earned vegetarian identity and hard-line food politics?

The answer, surprisingly, turned out to be no. I wasn’t a martyr for the cause; I just wanted to heal my aching body. So I got to work on eating like an O.

Blood Type Diet explained

“Which diet is the right diet?” asks D’Adamo. “The truth is, we can no more choose the right diet than we can choose our hair color or gender. It was already chosen for us many thousands of years ago.”

D’Adamo advocates ABO blood designation as the single most accurate determiner of how people should eat for optimal health and weight control. His conclusion, which opposes the one-path-fits-all approach of most mainstream diets and the USDA Food Pyramid, posits that Type Os experience optimal health as carnivores, faring best on highly beneficial red meat and oily cold-water fish—poultry and other seafood are neutral, while pork and goose are avoid foods. Type As live optimally as vegetarians, Type Bs as omnivores (and the best able to digest dairy products), and Type ABs as a blend of A- and B-eating habits. (For a list of beneficial and avoid foods to eat according to blood type, see “What to Eat If You’re…” on page 42.)

“In the conventional world, nutrition is broken down into macronutrients, fiber, calories, and percentages of fat and protein, and I think that’s one way of looking at food as fuel,” D’Adamo says. “But food is much more dynamic. It carries both additional positive and negative connotations based upon its reactivity and the biological processes it’s known to enhance or inhibit.”
Reactivity refers to the antibodies in blood and how they react with food. Each blood type has specific antibodies to ward off germs and foreign-invader blood cells, but these antibodies can also incidentally attack food proteins known as lectins. When you eat lectins that react adversely with your blood type, like those in wheat for an O like me, the proteins can clump and wreak havoc on the digestive system.

By contrast, D’Adamo asserts, our bodies are fully equipped to process ideal food lectins. Case in point: Type Os almost invariably have higher-than-average levels of stomach acid—good for digesting animal proteins—while Type As, who fare best on vegetarian foods, generally exhibit lower levels of stomach acid.

Anthropology also plays a part. According to D’Adamo’s book, Type O, “the Hunter,” is the original blood type, dating to the Cro-Magnon peoples who feasted on big-game animals. Type A, “the Cultivator,” developed later in the evolutionary timeline after hunting cultures adopted a more sedentary, agricultural lifestyle. Type B, “the Nomad,” arose when agrarians mastered herding and domestication. Type AB, “the Enigma,” resulted from the mixture of Type A and Type B peoples just over the last thousand years.

My new, carnivorous ways

For me, transitioning to the Type O hunter way of my ancestral forebears was overwhelming. One by one, I abandoned my favorite, now-off-limit staples—coconut, avocado, peanuts, lentils, kidney beans, wheat—and worked up the courage to tackle (egad!) beef, bison, and venison, along with other O-beneficial foods, such as artichokes, adzuki beans, chard, and walnuts.

Eventually, shocking myself and those who knew me, I filled my freezer with 25 pounds of Colorado-raised, grass-fed beef. Staring at the various vacuum-packed cuts was like walking into a library that only stocked books in hieroglyphics. Never having handled meat before, I made every mistake imaginable—defrosted wrong, trimmed wrong, spiced wrong, cooked wrong. One thing I wasn’t, though, was squeamish. The pooling of sticky crimson didn’t disgust me. Neither did holding the meat in my hands or slicing it. Preparing meat came so naturally that I started to think maybe I came from a long line of butchers. Or else, it truly was in my blood.

The more my eating changed, the better I felt: less congested, more energetic, more moisturized through my skin and scalp. I cried tears of joy when my hand rash went away. Unexpectedly, the chronic hip pain that I thought was due to stress suddenly wasn’t there to keep me up at night. After a lifetime of eating with my mind, I was now listening to my body—and it was thanking me.

You and the diet

Does my dramatic turnaround mean the Blood Type Diet is a panacea for all the world’s health woes? Probably not. D’Adamo cites a statistic that three out of four patients see improvement when they eat according to type, but he also points out that the people who benefit most are those whose health issues are not being served by conventional medicine and fly-by-night diets.

“If you’re a bread-eating Type O and you’re happy with your state of health and life is wonderful, you shouldn’t even be in the nutrition aisle in the bookstore,” says D’Adamo. “I write books for people for whom those other things don’t work.”

Wanting an outside perspective, I consulted Beth Reardon, RD, director of integrative nutrition at Duke Integrative Medicine. Reardon doesn’t use the BTD in her practice, but when I asked about the diet’s claim of a 75 percent success rate, she said, “Given the current eating patterns of the majority of Americans, I think most would benefit. The numbers can probably be interpreted several ways. Are they reflective of the Blood Type Diet or rather a move to overall healthier eating, with more whole foods?”

Evidently, the jury’s still out. But if you ask me, the BTD is worth a shot. Nowadays, when I briefly scorn the Type O guidelines to indulge in some of my lost food loves, I notice my head starting to itch, my hip getting tight, mucus building up, and my hand rash threatening a return.

Do I break the rules anyway? Absolutely. D’Adamo is very clear about the importance of remaining flexible: “Rigidity is the enemy of joy—I certainly am not a proponent of it. The Blood Type Diet is designed to make you feel great, not miserable and deprived. Obviously, there are going to be times when common sense tells you to relax the rules a bit, like when you’re eating at a relative’s house.”

I wholeheartedly agree. But when I cook and eat at home, rest assured I’m eating like the hunter that my blood type and body tell me I am.

What to Eat If You’re…

Type O

Eat this: Beef, lamb, venison, salmon, bluefish, cod, sardines, walnuts, pumpkinseeds, adzuki and pinto beans, chard, spinach, kale, artichokes, broccoli, turnips, plums, prunes, figs.

Not this: Pork, goose, caviar, lox, octopus, cheese, kidney beans, navy beans, lentils, cashews, peanuts, pistachios, white flour, wheat, avocado, eggplant, corn, potatoes, cabbage, blackberries, coconut, oranges, strawberries.

Type A

Eat this: Salmon, cod, sardines, soy milk, peanuts, pumpkinseeds, lentils, black beans, oats, rice, rye flour, artichokes, carrots, onions, pumpkin, tofu, spinach, apricots, blueberries, cranberries, cherries, pineapple.

Not this: Red meat, pork, goose, duck, bison, pheasant, cheese, Brazil nuts, cashews, pistachios, lima beans, kidney beans, garbanzos, white flour, wheat, cabbage, eggplant, peppers, potatoes, yams, bananas, coconuts, cantaloupe, oranges.

Type B

Eat this: Lamb, rabbit, venison, cod, flounder, mahimahi, halibut, feta, cottage cheese, kidney beans, navy beans, millet, rice bran, oats, rice flour, beets, broccoli, cabbage, carrots, eggplant, peppers, yams, bananas, cranberries, grapes, pineapple, plums.

Not this: Pork, chicken, duck, quail, clams, crab, lobster, sea bass, blue cheese, ice cream, cashews, peanuts, pistachios, sesame seeds, lentils, black beans, garbanzos, amaranth, wild rice, cornmeal, wheat, rye, artichokes, avocado, corn, olives, pumpkin, tofu, tomatoes, coconuts, pomegranates, rhubarb.

Type AB

Eat this: Lamb, rabbit, turkey, tuna, trout, mahimahi, cod, sardines, mozzarella, ricotta, feta, cottage cheese, peanuts, walnuts, green lentils, navy beans, millet, rice, oats, wheat flour, beets, broccoli, kale, alfalfa sprouts, eggplant, yams, tofu, cherries, grapes, cranberries, lemons, kiwi, grapefruit.

Not this: Beef, pork, chicken, duck, goose, clams, crab, flounder, haddock, lobster, butter, ice cream, parmesan, provolone, blue cheese, seeds, adzuki beans, black beans, kidney beans, buckwheat, cornmeal, artichokes, corn, avocados, peppers, radishes, bananas, coconuts, oranges.

[Type A] Spicy Curried Tofu With Apricots and Almonds

Serves 4 to 6

Spicy Curry Marinade

• 2 tablespoons tamari sauce
• 1 tablespoon fresh lemon or lime juice
• 1 tablespoon chopped fresh parsley or cilantro
• 1 tablespoon chopped fresh chives
• 1 tablespoon turbinado sugar
• 2 teaspoons curry powder
• 1 teaspoon black sesame seeds
• 1 cake firm tofu, drained and cut into squares

Stir-Fry

• 3 tablespoons olive oil
• 1 small onion or 3 scallions, sliced
• 3 carrots, sliced on an angle
• 2 cloves garlic, peeled and chopped
• 1/2 cup sliced dried apricots
• 1/3 cup sliced almonds

1. Combine marinade ingredients in a medium bowl. Add tofu cubes, tossing lightly once to coat. Let marinate 1 hour or longer.
2. Heat oil in a wok over medium-high heat. Add onion or scallions, and sauté 3 minutes.
3. Add carrots and garlic, and cook 2 minutes, making sure the garlic doesn’t burn.
4. Drain the tofu from the marinade.
5. Add tofu to pan, and cook until heated through. Add apricots and almonds, and cook 3 more minutes. Serve over white basmati rice.

nutrition info per serving (4): 292 calories; 19 g fat; 2 g saturated fat; 0 mg cholesterol; 15 g protein; 22 g carbohydrates; 3 g fiber; 506 mg sodium

[Type B] Lima Beans With Goat Cheese and Scallions

Serves 4

• 1 package frozen baby limas or
• 2 cups fresh lima beans
• 1 tablespoon olive oil
• 2 scallions, thinly sliced
• 2 cloves garlic, crushed and peeled
• 4 ounces goat cheese
• 3 tablespoons fresh parsley, minced
• Salad dressing of choice

1. Prepare lima beans if frozen, and place in a serving bowl.
2. In a skillet, heat oil over medium to high heat. Add scallions, and sauté 1 to 2 minutes until fragrant.
3. Add garlic, turning briefly until it just begins to color. Add scallions and garlic to lima beans. Remove from heat.
4. Pour 2 to 3 tablespoons of salad dressing over the bean mixture, and toss gently. Crumble goat cheese on top, and garnish with parsley. Serve at room temperature.

nutrition info per serving (using 2 tablespoons light italian dressing): 254 calories; 15 g fat; 8 g saturated fat; 29 mg cholesterol; 14 g protein; 17 g carbohydrates; 5 g fiber; 209 mg sodium

[Type AB] Spelt Berry and Rice Salad

Serves 4 to 5

• 1 cup cooked spelt berries
• 1 to 2 cups cooked rice (any variety)
• 1 cup sautéed maitake mushrooms
• 3 tablespoons chopped fresh parsley
• 3 tablespoons olive oil
• Salt

1. Combine all ingredients, and mix well. Serve at room temperature. Feel free to add scallions, garlic, and other spices, such as coriander and a dusting of cumin. This dish will hold in the refrigerator for up to 4 days.

nutrition info per serving (4 servings, using brown rice): 215.1 calories; 11.5 g fat; 1.6 g saturated fat; 0 mg cholesterol; 3.9 g protein; 29.5 g carbohydrates; 3.5 g fiber; 5.5 mg sodium