On Sat, 19 Jul 1997, Dean Esmay wrote:

> Well, perhaps a considerable amount.  If there -are- some humans whose
> systems have adapted them to having slightly different needs, it's probably
> important to know that.  I may need to pick up D'Adamo's book....

I broke down and did just that.  It's quite interesting in that
D'Adamo, like Audette and Gilchrist, claims that most
diet-related problems are immunological in nature.  The core of
his argument is this:

Foods contain lectins, which are proteins "which can interact
with surface antigens found on the body's cells, causing them to
agglutinate," and this agglutination response is what causes
trouble.  The main point is that blood type determines which
lectins interact and which don't.

An important consideration is that he claims that these
interactions are empirically verifiable.  That is, you can
observe the agglutination response *in vitro* by applying a
sample of lectin to a blood sample.  You can then see that, say,
beef protein affects type A blood cells differently from the way
it affects type O blood cells.  Thus, his dietary recommendations
are based upon these in vitro observations in conjunction with
clinical observations.

Interestingly, although the type A diet is basically vegetarian,
it is by no means a "standard" vegetarian diet.  For example,
although most meats are in the "Avoid" category, chicken and
turkey are in the "neutral" category, meaning that they are well
tolerated, if not especially beneficial.  Among fish, cod,
salmon, trout and sardines (among others) are in the "Highly
beneficial" category, while bluefish, catfish, flounder, and
haddock are in the "Avoid" category.  For type As, peanuts are
beneficial, walnuts are neutral, and cashews are to be avoided.
Lentiles, pinto beans, and black beans are beneficial, but limas,
kidney beans and garbanzos are to be avoided.  Among grains,
amaranth, buckwheat, and kasha are beneficial; rice, barley and
corn are neutral; wheat and wheat products are to be avoided.

This is just an illustration of the way in  which the dietary
recommendations cut right through the middle of the usual
vegetarian plan.

According to D'Adamo, the A blood type (the second to appear)
appeared about 40,000 years ago, but not in large numbers until
agricultural times.  This implies that it was a modestly bad, but
not disastrous, mutation until agriclture arrived and selection
began to favor it.

How believable is all this?  I guess it depends upon the quality
of his data, and I'm not yet in a position to make a judgment.
Most former vegetarians would not be in a position to say that
they've "been there, done that," simply because his vegetarian
guidelines are so idiosyncratic, and the other blood type diets
are equally so.

Todd Moody
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