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Blood type diet: a skeptic's view
Last reviewed: 04.07.2025
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[ Blood Type Nutrition Theory: Is It True?
Peter D'Adamo, who wrote the book "Blood Type Diets" that became so popular all over the world, ambiguously claims that eliminating unnecessary foods from the diet and choosing the necessary ones will give a person the opportunity to lose weight and improve their health comfortably.
According to D'Adamo's theory, each blood type has its own products. Some must be included in the menu, others - not to eat, because the body perceives them as foreign and reacts with allergies and fat deposits. That is, a diet that is good for one blood type is bad for another.
What do Peter D'Adamo's opponents say? They insist that the world-famous nutritionist does not support his arguments with research and scientific facts.
What do opponents of the blood type diet say?
№1. Irrelevant division into blood groups
That is, say opponents of the blood type diet, dividing people into 4 categories - each with their own group, 1st, 2nd, 2nd and 4th - has long been irrelevant. The reason is that modern scientists have already identified as many as 33 blood groups, for each of which it is quite difficult to create a diet.
#2. Inconsistencies in D'Adamo's Theory
The creator of the Blood Type Diet, Peter D'Adamo, writes that some of the most harmful substances to the human body are proteins called lectins. These proteins tend to have a negative effect on the functioning of the gastrointestinal tract and contribute to a weakening of the immune system.
This happens because they can stick together with other proteins that originate from erythrocytes. As a result, a person develops dysbacteriosis, inflammation of internal tissues, especially the walls of the intestines and stomach.
Even a small amount of these proteins entering the body, the scientist writes, can provoke disturbances in the body, especially one weakened by disease.
Where is the evidence that these substances actually destroy the body, opponents ask.
№3. Some products are not represented in the diet at all
For example, seafood, which is generally healthy and loved by many. Also, skeptics say, the blood type diet does not take into account the individual life schedule of a person.
That is: there is no clear schedule of what products to include or not include in the diet, based on age, rhythm of life, level of physical activity, climate and other individual components of a particular person’s life.
#4. There is no diet for mixed blood types
Firstly, a blood group can be mixed, which means that completely different products will be beneficial or harmful to it than to a “pure” blood group.” Secondly, skeptics say (and they are right), a blood group also has a Rh factor – positive or negative.
The author of the diet does not give any recommendations on this matter. What should people with negative Rh factor do? For them, it is probably necessary to develop 4 more individual diets by blood type.
So, you have become familiar with the views of those who consider the blood type diet to be imperfect and definitely requiring some improvement. If these arguments have not greatly influenced your point of view, proceed to the diet. If they have greatly shaken your opinion about this nutrition system, it would not be a bad idea to contact a nutritionist and adjust it.
Lose weight easily and comfortably!