3 Reasons To Avoid The Blood-Type Diet


Eat Right For Your Blood Type, a book by Dr. Peter J. D'Adamo, isn't a nutrition work for Twilight fans. The author's concept, simply put, is that everyone can and should follow an optimal diet according to whether their blood type is A, B, AB, or O.

It all sounds very scientific, doesn't it, in a nerd-glasses-and-lab-coat kind of way? You know there's some 23-year-old actress out there waiting to offer a gushing endorsement of this diet as the cure for everything that ails everyone on Earth.

Indeed, we're all born with a different set of genetics, which we know contributes to our risk for some diseases and other medical conditions. To eat in a manner that coincides with our genetic makeup, while improving our health? Makes perfect sense, right?

The problem is, unless you recoil from garlic and sleep in a coffin, the so-called blood-type diet kind of, well, sucks.

The good doctor believes that certain foods are good for your blood type, and that others are dangerous. Eat foods from the latter category, and you may experience a variety of health issues, ranging from inflammation and bloating to a slower metabolism and even diseases such as cancer. Or so the book says.

Blood Type Specifics

Here's how he breaks down the dietary specifics for each blood type:

O = "old" or ancient times

  • Is intolerant to dietary and environmental adaptations
  • Lean meats, poultry, fish
  • Restrict grains, legumes
  • Responds best to stress with vigorous exercise
  • Requires an efficient metabolism to stay lean and energetic

A = "agrarian"

  • Has a sensitive digestive tract
  • Vegetarian diet
  • Tolerant immune system
  • Adapts well to settled dietary and environmental conditions
  • Responds best to stress with calming actions and gentle exercise
  • Requires agrarian (based on agriculture) diet to stay lean and productive

B = "nomadic"

  • Has a tolerant digestive system
  • Can tolerate the most flexible dietary choices
  • Low-fat dairy, meat, produce
  • Avoid wheat, corn, lentils
  • Responds best to stress with creativity
  • Moderate exercise
  • Requires a balance between physical and mental activity to stay lean and sharp

AB = "modern"

  • Has a sensitive digestive tract
  • Avoid chicken, beef, pork
  • Should eat seafood, tofu, dairy, most produce
  • Responds best to stress spiritually, with physical verve and creative energy
  • AB is an evolutionary mystery
3 Reasons To Avoid The Blood-Type Diet

The good doctor believes that certain foods are good for your blood type, and that others are dangerous.

Eat Right For Your Blood Type gives you portions of the best foods listed for you. It also lists foods that encourage both weight gain and loss for each blood type. He also offers case examples, answers common questions, and addresses different situations that might arise (food allergies, diseases etc.) for each group.

Why This Diet Isn't For You

Unfortunately, the book raises more questions than it answers. I've singled out three reasons in particular why this diet isn't necessarily for you:

1. The Diet is Short on Science

The recommendations made on Bodybuilding.com are based on science and experience. The take-home:

  1. Eating small, healthy meals throughout the day will help control hunger and manage insulin levels, giving you a constant source of energy.

  2. Getting enough quality protein will ensure that you are building a lean-yet-muscular physique.

  3. Using the right supplements in the right doses at the right times will support your overall health and training program. Though Eat Right for Your Blood Type sounds scientific, it's anything but.

2. The Diet Isn't Individualized

At first glance, Eat Right For Your Blood Type seems individualized-it zeros in on your blood type. However, it doesn't take into account your medical history, medications, current or target body weight, food likes and dislikes, food allergies or intolerances, diet history, and more. The ideal dietary approach for you should account for all of these factors.

3. The Diet Does, Bizarrely, Account for Ethnicity

In the Eat Right For Your Blood Type diet, foods are portioned out differently based on your ethnicity. There's no rhyme or reason for doing this.

Though Eat Right For Your Blood Type isn't a harmful diet, it also isn't based on any science; therefore, there's no guarantee or even a suggestion that it will work for you. You'll be better off learning from the articles on Bodybuilding.com and taking your own situation into account to create a plan that meets your specific needs.

About the Author

Marie Spano

Marie Spano

Marie Spano, MS, RD, Vice President of the International Society of Sports Nutrition (ISSN) is a registered dietitian with a MS in Nutrition...

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