On Fri, 17 Jul 1998, Ray Audette wrote:


> Even those blessed with glucose, gluten and
> lactose tolerance experence high rates of diseases that don't exist in
> Nature.

Glucose is abundant in paleolithic foods, namely fruits, so it
really doesn't belong in this list.  As for the gluten and
lactose tolerant, I'd be interesting in learning how you know
about their disease rates.  It would be a very interesting
epidemiological study that isolated the variables of gluten
tolerance and lactose tolerance and correlated them with disease
rates, but I don't believe such a study has ever been done.
Unfortunately, the number of people who eat gluten and lactose is
probably far greater than the number who tolerate them well, so
the disease rates probably reflect the *intolerant* more than
the tolerant.

The problem, as I see it, is this:  As human beings migrated from
place to place, their food supply changed.  With each change, a
certain percentage of people would get sick and there would be
instense selection pressure against their genes, but in favor of
the genes of those who did well on the new food.  At the same
time, there would be no selection pressure to retain adaptation
to the previous foods that were no longer available, so if
adaptation to new food X involved maladaptation to old food Y,
there was no obstacle to this.  Adaptation to new food sources
would always be less than complete, until a very long time had
passed.  The point, however, is that there is no reason to expect
that these scattered populations, all struggling to adapt to new
food sources, would remain well adapted to their "primordial"
foods.  The analogous point, which I have mentioned before, is
that as humans scattered around the globe they adapted to local
conditions in many ways, such as skin color, type of hair, etc.
In so doing, they became maladapted to the conditions in which
they originated.  If you place my wife, who is Irish, redheaded,
and very fair, and put her on an African savannah in a loincloth,
she will soon be dead of exposure.  The fact that she is
descended from people who lived there quite comfortably doesn't
change that.  Likewise, there is no particular reason to think
that an Inuit would thrive on a diet that keeps a Kalahari
bushman healthy.  Or vice versa.

> The ideal is closer to the diet of Neanderthal than to even the
> earliest neolithic people.  Going back further also makes you more
> equally related to all people on earth at that time and makes racial and
> geographic differences in people less important (sorry blood type
> theorists).

Then you need to explain why certain of the "diseases of
civilization", such as CHD and many cancers, tend to favor type A
blood.  You also need to consider the implications of the fact
that immune response to many foods varies with blood type.
"Going back further" makes us all more similar to each other, but
only by ignoring the diversity that has arisen since then, as I
pointed out above.

Hemagglutination is one of the main mechanisms by which the
immune system targets foreign proteins.  If different blood types
are agglutinated by different proteins, why isn't this relevant?

Todd Moody
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