The Blood Type Diet suggests that your blood type (ABO) should guide what you eat.
Here is one example of an online chart of foods for different blood types.
There is controversy about the science behind this diet.
The diet was popularized in the 1990’s. The premise was that lectins (various proteins with inherent agglutinating (clumping) properties found widely in foods, agglutinated the cells of some blood types, but not others. However, with very few exceptions (ie. lima beans), research does not appear to confirm that food lectins react differently with different blood types (Nachbar, 1980).
What appears evident is that lectins, present in many plants (and possibly in dairy if the animal is grain fed), are notably abundant in legumes and grains, and in the nightshade family, and appear to be difficult to digest —for everyone.
Consider that grains, for example, may never before have been ingested in the quantities and frequency of our modern diet.
So, it may be beneficial to lessen exposure, one method possible being the rotation of high lectin-containing foods only every 8 days. But also consider food preparation techniques that make these foods more digestible, like soaking and longer cooking.
Dr. Peter J.D’Adamo, ND, the author of Eat Right 4 Your Type: The Individualized Diet Solution to Staying Healthy, Living Longer and Achieving Your Ideal Weight, suggested that poorly digested lectins might interact in the lining of the stomach, or in the intestines, or be absorbed intact into the blood resulting in reactions in various organs (D’Adamo,p.23). In Digestive Wellness, 4th Edition, Elisabeth Lipski, Ph.D. also suggests that poorly digested lectins can cause problems, specifying that lectins “bind to carbohydrate molecules” throughout the body and cause clumping of these molecules (Lipsky, p.157). She also speaks of resulting damage to the GI mucosa, leading possibly to leaky gut, and also suggests lectins “degranulate mast cells” resulting in the production of IgE antibodies (Lipsky,p.157).
It may be advisable for everyone to pay attention to proper food preparation, INCLUDING of at least the above-mentioned high-lectin foods : possibly revisiting traditional food preparation methods including soaking and fermentation. Lipsky suggests long cooking, or pressure cooking, in addition to taking digestive enzymes, as a means to help proper digestion of lectins (Lipsky, p.157).
RotationDietPlus Software Instructions to rotate high-lectin foods:
Lectins are particularly abundant in wheat, legumes, nightshades, and possibly dairy.
- for wheat shift click on wheat to see it struck off the diet;
- for the entire #15 grass family including wheat, double click on any #15 to highlight the whole family, then use delete to strike off all from the diet;
- for all grain-like foods including the entire #15 grass family plus amaranth, quinoa, buckwheat, click on the grains category to strike all from the diet;
- for legumes, click on the legumes category to see all struck from the diet;
- for nightshades, double-click to highlight family #27. Delete to have the whole family struck off the diet;
- for dairy : click on the category to see all struck off the diet. Return eggs to the diet by shift-clicking each individually …etc.
The Rotation Diet Plus©Software helps to manage complex diets. Consult a qualified health professional for any dietary change or disease condition.