The “blood type” diet is the creation of Peter D'Adamo, who is not a nutritionist, but rather a naturopathic doctor.
According to him, the secret to staying healthy and slim is by eating according to your blood type (whether that be A, B, AB, or O). D’Adamo states that while some foods are healthy for one blood type, they can be downright dangerous for another.
According to D’Adamo, for example, Type O’s should eat high amounts of meat and avoid grains, as this blood type can be traced back to our oldest hunting ancestors. Type A’s should stick to a vegetarian diet, but Type B’s and ABs, who are related to nomadic tribes, can eat a little of everything in moderation.
Anthropologists were up in arms when this diet first came out, since there is no reason to believe that prehistoric humans, who according to D’Adamo all ate vast amounts of meat, followed the exact same diet.
D’Adamo continues by claiming that eating the wrong foods for our blood types results in a very serious condition known as agglutination, wherein red blood cells clump together, blocking blood flow and not allowing some cells to get the oxygen they need.
According to D’Adamo, this is all due to lectins, proteins found on the surfaces of foods that are extremely dangerous when eaten by the wrong blood type.
I can’t help but wonder -- if we’ve all been unknowingly eating from all the food groups and going against our blood type needs, why aren’t some of us keeling over after just a few years of eating supposed toxic food (like whole grain breads) on a daily basis?
Furthermore, many of these catastrophic statements (i.e.: when a type A person drinks milk, agglutination happens immediately) are never explained. How much milk are we talking about? A sip? A cup? How many times a week?
Regardless, lectins are by no means a health concern. Not only do most of them disappear with cooking, our digestive system also destroys them (a factor D’Adamo’s lectin research completely fails to take into account).
This part of his theory reminds me of that now infamous e-mail forward that went around in the late 90s, explaining that a penny submerged in a glass of Coca-Cola for 24 hours disintegrates, “so imagine what it does to your insides!” Yeah, except a penny doesn’t have gastric acids that prevents those same chemicals in soda from destroying our intestines overnight.
More reasons as to why this diet is just a ploy to get you to spend money? The blood types D’Adamo uses is one of severeal ways of classifying human blood. This diet would be the equivalent of someone creating meal plans based solely on your eye color. It’s irrelevant, scientifically inaccurate, and a complete gimmick.
I also find it especially noteworthy that no matter what your bloodtype, D’Adamo recommends cutting out processed foods, added sugars, and junk. It doesn’t take a genius to recommend that as a way to quick weight loss.
At the end of the day, the “Eat For Your Blood Type” diet is just a reduced-calorie diet (some of the diet plans clock in at just over 1,000 calories – who WOULDN’T lose weight?) with a new premise.