Despite the general consensus from qualified professionals, I am still seized by a very powerful urge to tear my hair out every time I pick up “Eat Right 4 Your Type!” This diet is a perfect example of how the ridiculous, when presented in print, somehow becomes acceptable and plausible.
This diet is also a good one to use when illustrating the confusion between cause and effect; for some people of certain blood types, the “Eat Right for Your 4 Type!” diet will work. But it’s not because of some unique tie-in between your blood type and your diet. It’s simply because the diet in question is a sensible one; moderate in calories and low in refined grains and starchy carbohydrates.
The crux of this diet quite simple: D’Adamo postulates that your blood type evolved a certain way, and it is the determining factor in what you should be eating. Each of the 4 diet plans specific to each blood type (O,A,B, and AB), are carefully formulated to avoid foods containing the “protein lectins” incompatible with it. According to D’Adamo…
“… when you eat a food containing protein lectins that are incompatible with your blood type antigen, the lectins target an organ or bodily system (kidneys, liver, brain, stomach, etc.,), and begin to agglutinate blood cells in that area”.
Michael Klaper, M.D., had this to say about that statement…
“For me what really pushes the “blood type” theory beyond the limits of believability is D’Adamo’s postulation that lectin proteins on some foods cause blood agglutination in people of certain blood types who are “not genetically/evolutionarily suited” to eat those foods. Agglutination is a very serious, and potentially life-threatening, phenomenon, whereby the red cells in the bloodstream stick together, forming irreversible clumps.”
Unfortunately, D’Adamo offers no proof or documentation of any sort to quantify his statements. There is no peer reviewed data to validate any of his theories, no credible references of any sort.
The best he can do is state his theory is valid because he himself has done tons of research to prove it so. In other words, we are not to question this theory, but to accept it at face value (the almost total lack of footnotes in the book, especially to validate the many general statements, is particularly alarming).
At one point in his book, Dr. D’Adamo claims to be in the eighth year of a ten year trial testing the blood type diet on reproductive cancers and showing impressive improvements in life expectancy. Well, “Eat Right” was published in 1996, and to date, there has been no published study showing anything of the sort. Also, the cost of such a properly conducted trial would be significant for even the major drug companies: if such a trial existed, where did D’Adamo get his funding, and why haven’t the results been shared with the world?
Several experts have gone on record in published journals refuting D’Adamo’s theory of blood type mutation; other clinical data simply contradicts his theory (see Molecular Biology and Evolution, Vol 14, 399-411, Rev. Bras. Hematol. Hemoter). Not surprisingly, this further damages the credibility of his argument.
Perhaps even more disturbing is the fact that the symptoms attributed by D’Adamo to “lectin agglutination” mirror the symptoms of many other diet-related disorders—yeast overgrowth, nutritional deficiencies, bowel toxicity, allergies, heavy metal toxicity, hyperinsulinemia, prostaglandin imbalance and so on.
In other words, this is at best, only a theory… and one on very shaky ground, at that.
Believe it or not, D’Adamo even goes as far as to predict personality traits and establish exercise programs on the basis of blood type. For instance, he indicates blood type A’s exceed psychologically at planning and networking, and are decent, and law abiding people.
The problems don’t end here; there are some serious issues with D’Adamo’s theory linking blood type with diet. For instance…
D’Adamo postulates that blood type A evolved sometime between 25,000-15,000 B.C. in response to the domestication of livestock and farming. Blood type A, for example, apparently allowed people to “better tolerate grains and other agricultural products”.
What’s the problem with this? There are two…
First, most experts agree that mankind made the jump from hunter-gatherer to farmer about 6-10,000 years ago. On the outside, this switch-over began no earlier than 15,000 years ago, at which time the last ice age was drawing to a close.
The significance of this?
Well, geneticists theorize that it takes many thousands of generations to bring about any sort of significant genetic evolutionary response. In other words, our switch from hunter gatherer to farmer happened much too recently in our history for it to have resulted in the evolution of a new blood type. Since blood type A obviously evolved as a result of some other stimuli, D’Adamo’s theory is a bust.
As a reader, one can feel D’Adamo grasping at straws as he develops his theory for blood type B, which evolved in the Himalayans “perhaps” as a result of climactic change.
When it comes to actual diet advice itself, D’Adamo doesn’t fare much better.
In fact, he consistently provides recommendations that are totally incorrect;. For instance…
Type B’s are encouraged to eat rice cakes (pure carbohydrate with a glycemic rating of pure glucose), which are perhaps the dieter’s worst enemy. Peanuts, on the other hand, are said to cause hypoglycemia for type Bs. But we know peanuts have a very low G.I. (glycemic index) rating, and don’t generate fluctuations in blood sugar levels. Statements like this totally contradict what we know to be true, and must be validated with some sort of proof or reference. Again, D’Adamo provides none.
Believe it or not, the entire book is jam-packed with similar misinformation, generalities, and information that is just plain wrong.
Despite this, around 50% of those trying “Eat Right 4 Your Type!” will experience positive results, but certainly not because D’Adamo’s theory is correct. Here’s why…
In North America, the predominant blood type is type O. Just under 50% of the Black/People Of African descent population is type O, while the Caucasian population comprises just slightly less (about 45%).
D’Adamo’s blood type O diet focuses on restricting breads and grains, while increasing lean meat, poultry, and fish. This will effectively place the dieter on the “cusp” of ketosis, similar to a modified Atkins diet. It will also eliminate vacillating blood sugar levels, encourage lean muscle growth, and stimulate weight loss. In short…
The plan for type O will work, simply because it sticks to proven diet fundamentals, NOT because there’s a link between blood type and food consumption. Don’t make the mistake of confusing cause and effect here.
If your blood type is anything other than type O, you’ll be lucky to achieve anything on this diet.
Despite the lack of clinical evidence validating Eat Right 4 Your Type, my review has generated more than its fair share of angry visitor feedback over the years.
“Who are you”, some ask, “to question D’Adamo’s theory? Are YOU a doctor?”
My answer is always the same…
No, I am NOT a medical doctor, and neither, as a matter of fact, is D’Adamo. Secondly, using the prefix “Dr.” in front of your name does not allow you to make broad, sweeping generalizations, present statements that contradict established theories and practices and promote your own theories without providing one iota of supporting evidence. The onus is on D’Adamo to prove his theory is valid. I have simply pointed out the obvious: none of his theories have any supporting evidence, and there are plenty of credible qualified professionals who contest his conclusions.”
You don’t need to be a doctor to do that.
To investigate a REAL diet, check out Tom Venuto’s Burn The Fat, reviewed here!