112 Joel Fuhrman, M.D.ing his book fearing for their lives if they eat a food that D'Adamo
claims is dangerous for their type. But when we compare the infor-
mation presented by D'Adamo with the information that is available
in the scientific literature, the picture just doesn't match.
Again, part of what D'Adamo says is true, but his interpretation
is so exaggerated and distorted as to make his assertions almost val-
ueless. Not all lectins are toxic; most are even nutritious, with signif-
icant beneficial effects. Only some lectins are truly toxic, such as in
red kidney beans, and need to be destroyed by cooking prior to eat-
ing. But most other lectins, such as tomato lectins, have been shown
to be harmless. The beneficial effects of plant lectins include anti-tumor
and anti-cancer activity, meaning they inhibit the induction of can-
cer by carcinogens.^50 Some of the most fascinating and consistently
observed biochemical effects of plant lectins are their inhibitory ef-
fect on protein synthesis in abnormal or malignant cells, but not in
normal cells. They may prove to be a useful tool in treating cancer in
the future.D'Adamo states on page 27 of his book that "the effects of lec-
tins on different blood types are not just a theory. They're based on
science." His conclusion, he explains, has been made on the basis
of urinary indican readings in his patients. However, indican in the
urine does not register antibody-antigen reaction or agglutination.^51
This outmoded test is notoriously unpredictable and is also affected
by unabsorbed protein. D'Adamo also claims that his conclusions
have been based on the agglutination he saw in blood exposed to
food-derived lectins. Don't think agglutination on a microscopic slide
means much — our blood is supposed to agglutinate when removed
from the body and exposed to air. To call his unjustified conclu-
sions and his wild claims scientific is an insult to every legitimate sci-
entist.On a positive note, D'Adamo's book raises the awareness of the
potential problems of lectins in certain foods and the likelihood that
some of us may be genetically sensitive to specific food lectins. It is
controversial whether lectins are a significant contributor to disease,
but the evidence is suggestive. This is a valuable subject to pur-
sue, and possibly D'Adamo's work will lead to more research on this
subject.Many lectins are powerful allergens in susceptible people and
may partially explain food sensitivities that do not correspond with
IgE (the typical allergy) blood testing. Of particular interest is the im-