(continued from previous part)

> Another issue comes up with cardiovascular disease and cancer.
> First of all, these two diseases are largely associated with
> lack of exercise in addition to diet, genetics, and daily
> living. To insinuate that eating as a hunter-gatherer will
> prevent these diseases because they were rare in the
> hunters/gathers of the past is only telling half of the truth.
> The fact also lies that as we have evolved, So have genetic
> mutations (also a large factor in heart disease and
> cancer--more so than diet or exercise). In addition, we also
> have that second bystander called pollution. In toady's
> society, you would literally have to escape to some remote
> tribe who is far enough from most other people to be exposed to
> pollution. Unfortunately, it is very difficult to escape
> environmental changes that have occurred since the
> hunters/gatherers of the past.

Here it seems to me Ms. Machalka is injecting a separate issue of concern
(and one that I in fact very much agree with, aside from the issue of
misinformation) into a discussion that was about a different point. And to
either miss or brush aside this latter point (it's not clear which may have
occurred) unfortunately misconstrues one of the main themes of the
interview. That theme/point being, not to suggest nor even imply that
eating like H/Gs did would completely prevent the major degenerative
diseases under the environmental stressors/pollutants, etc., of the modern
world, but simply that the H/G experience shows omnivorous diet/meat
consumption *per se* (in and of itself only) cannot be blamed for the major
degenerative diseases such as increased cancer, cardiovascular diseases,
etc.

As reflected in the title "Paleolithic Diet vs. Vegetarianism," much of the
interview's concern was to assess and where necessary counter vegetarian
propaganda in light of paleo evidence. The thrust of the point about H/G's
meat consumption and rarity of cancer/ cardiovascular disease was to rebut
fallacious vegetarian assertions that conflate the known cancer-promoting
effects of modern feedlot meats as well as their context in Western diets
with the effects of *any* meat or omnivorous diet, which the H/G data
clearly demonstrates is erroneous. (Elsewhere on the site we label this
"The 'Omnivorism = Western Diet' Fallacy" which typifies so much of
vegetarian thinking.)

What *is* very much implied in the interview is that if we emulate the
dietary aspect of the H/G lifestyle, then so far as that aspect is
concerned, we need not fear increased disease risk from it; but not by any
means that we can count on being disease-free in today's polluted world, or
if we do not exercise, avoid environmental toxins, etc. The latter
insinuation seems a bit of a far-fetched one that not even Beyond Veg's
most vocal critics in the vegetarian movement have leveled at what is in
the interview or on the site. Most people seem reasonably intelligent
enough to implicitly realize that where cancer is concerned, diet is one
thing, while environment, exercise, pollution, and all the rest is another.

> It is true, however, as Mr. Nicholson states, that trans fatty
> acids and saturated fats are researched and probably are more
> highly associated with both cancer and heart disease than
> unsaturated fats (especially monounsaturated fats.)

Let me pause a moment here, as the above acknowledgment calls for a brief
pemmican break before wrapping this thing up. Plus I gotta go have another
look-see at Amazon.com to see if Ray's book ranking has changed in the last
two hours. Don't go away, I'll be right back. :*) .....

> The issue of increased brain size: it is true that fat helps
> support brain growth. Actually, the human brain grows until we
> are about 2 years old, and modern nutrition and medicine both
> insist that babies are fed enough fat to support brain growth.
> However, even though Mr. Nicholson has found in his research
> that brain size decreased when people stopped eating so much
> meat in the last 10,000 years. He claims that a decrease in
> animal foods is correlated with a decrease in brain size. Lets
> not forget that correlation does not mean cause and effect.
> Increased ice cream consumption is correlated with increased
> number of murders, but that does not mean that eating ice cream
> causes people to murder. Maybe something else happened 10,000
> years ago that decreased brain size.

This is a very salient point and one that I was very much aware of.
However, although I vaguely alluded to the potential correlation/ causation
issue (from http://www.beyondveg.com/nicholson-w/hb/hb-interview1f.shtml:
"This evidence of decreasing brain size in the last 35,000 years, and
particularly the last 10,000, represents important POTENTIALLY
CORROBORATIVE evidence for the continuing role of animal foods in human
brain development,...") it certainly could and should have been stated more
clearly. I appreciate this comment and will be making an amendment to that
effect in the interview's update section.

Before closing, there is one related note on the topic of diet and
evolutionary brain size increase here that should be mentioned.

While acknowledging that correlation alone is not causation, at the same
time I think we also have to acknowledge that there seem to be no other
worthy hypotheses as yet to explain the dietary basis that could have
supported the dramatic increase in brain size during human evolution. At
least I'm not aware of any alternative hypotheses other than the recent
Wrangham cooked-tuber-starch-theory paper that appears in the Dec. 1999
issue of Current Anthropology ("The raw and the stolen: cooking and the
ecology of human origins"), which turns out to be weak and implausible at
best.

This alternative thesis (the only one I know of--but if someone knows of
another, I'd be interested in hearing) has 3-4 major holes based on what I
have been informed of via paleo research circles. These will no doubt be
attracting scrutiny in the future from paleo specialists who were
overlooked during the peer-review process for this paper. (The track record
of the paper's primary author, Richard Wrangham, is in primatology, not
paleodiet.)

Here I'll mention the two I am most familiar with myself, the first of
which is that the hypothesis fails to even mention let alone address the
crucial DHA and/or DHA-substrate adequacy issue. This key long-chain fatty
acid of prime importance to brain development has to be dealt with in any
serious theory of how evolutionary brain enlargement occurred, and the fact
the tuber hypothesis ignores it altogether is perhaps the most telling and
fatal of the holes. (Unfortunately, it seems that historically, a common
error in discussions of evolutionary brain expansion has been to focus
predominantly or only on the quantitative issue of the caloric energy
required to support it, while failing to realize the qualitative issues--as
exemplified here by DHA and other long-chain fatty acids necessary for
efficient brain growth--present an equally critical bottleneck.)

The hypothesis is further contradicted by the evidence of 8% decrease in
human brain size during the last 10000 years, despite massive increases in
starch consumption since the Neolithic revolution which began at about that
time, which again was not mentioned nor addressed in the paper. (Whether
the starch is from grain or tubers does not essentially matter in this
context.) Meat and therefore presumed DHA consumption levels, both positive
*and* negative-trending over human evolution, track relatively well not
simply with the observed brain size increases during human evolution, but
with the Neolithic-era decrease as well, on the other hand.

I could say a bit more about this except I don't want to unduly spoil
things, since the possibility exists that we (another author who is
interested, not me) may be adding material examining the
cooked-tuber-starch thesis on Beyond Veg at a later date. (Although if a
peer-reviewed paper from the paleo camp deconstructing the flaws comes out
in the interim, we would probably wait or incorporate and/or substitute
information from that into our write-up to save duplicate effort.)

--Ward Nicholson <[log in to unmask]>