Richard Keene writes:

>Probably the "best" refutations of Paleo are on the Vegan sites.

The best argument I have seen from scientifically oriented vegans is that
vegetarian diets are an "improvement" over the evolutionary baseline. You
hear this idea mostly on the Sci-Veg listgroup. The rationale is that
evolution selects for reproductive success (greatest number of surviving
offspring) rather than longevity (which as far as it goes, is true). Then
when you compare clinical evidence of disease incidence of vegetarians/
vegans (and maybe longevity, although I'm not sure about that) against
omnivorous control groups, the omnivores do much worse. Also, the example
of vitamin E (or other nutrients) is sometimes given: When you look at the
beneficial effects from vitamin E supplementation and so forth as seen in
clinical trials, the nutritional levels at which the effects are observable
come from levels of supplementation considerably higher than you would get
from an omnivorous diet alone.

So the idea here is why stop with evolution--we can improve on it with
vegan diets and with supplementation. (By the way, for this reason--which
seems to spring out of the ethical idea that just because we behaved toward
other creatures or our fellow human beings some way in the past doesn't
mean we should keep doing it today--the scientifically oriented vegans
don't see "naturalism" as any sort of reason in paleo's favor. They really
don't care about naturalism as a rock-bottom value.)

The basic logic here is okay as far as it goes if you don't look at it too
closely, but there is a serious fallacy or two or three here including
problems of evidence when you do look closer. To begin with, the vegan
paleo refutation falls into the logical trap of equating the SAD diet
(i.e., the "omnivorous control" group in the clinical trials) with ANY/ALL
omnivorous diets such as paleo. This really is an astoundingly massive
logical hole to fall into when you stop to think about it. And besides the
fact that everyone already agrees the SAD diet is promotive of degenerative
disease, it is also low in essential vitamins/minerals compared to
reconstructed paleo diets (or extant H/G diets) and thus a poor standard
for making comparisons of this nature as well, regarding vitamin E, for
example.

The second problem is that while evolution may not select specifically for
longevity (true enough), it does select for, and result in, highly
integrated, homeostatic organisms with many intertwined subsystems that are
highly interdependent with each other because they have all had to co-adapt
with each other. When you attempt to reorder the balance somehow with a
diet significantly different from the evolutionarily selected one, you can
almost count on a few destabilizing effects. (These are typically ignored
by those with a vegan axe to grind, however; just look at DHA levels in
vegans in clinical trials, even those who supplement with EPA, flax oil,
etc., which don't look too good.)

If one is going to talk about improving on evolution, the best thinking I
have seen for deviating from it if you are interested in longevity is the
approach that one should *not* try to change one just one discrete
nutritional constituent or variable like vegan- vegetarianism does (which
will be highly likely to backfire in unanticipated areas due to
destabilizing the balance, as it apparently does with DHA). Instead you
would try to affect all the variables equally at once, by turning down the
"aging rate" of all systems simultaneously to try to maintain the
homeostasis and not upset the balance. What this basically amounts to is
keeping the dietary constitutents the same but doing "caloric restriction,"
about which there is a lot of research by now, and of course it seems to
work in most of the animal experiments so far. But of course most of the CR
people are very much into fish oils, DHA, and other things you get from
animal products, and it isn't an argument for vegetarianism per se,
although some CR pracitioners do try it that way (Lisa Walford, for one, I
think).

On the other hand, if you follow the CR Society listgroup (the main
internet listgroup for practitioners), and you pay close attention, you
find a fairly significant incidence of being hungry a lot, periodic
complaints about what to do abou;mood/energy/emotional flatness or
depression, decreased sex drive, etc. So there can be costs in the kind of
life that results for some of those who practice it. (See the "CR side
effects survey" at
http://www.infinitefaculty.org/sci/cr/John_Woodman_Survey.htm for a brief
rundown.).

Also, what I think the vegans divert attention from in the case of
hunter-gatherers, when they point to the shorter lifespans, is that
longevity is a compositive measure of many different causative factors, not
just some vague thing that means something by itself. There are many
potential specific processes that contribute to it that you have to look
at, and one of the biggies has to do with avoiding the degenerative
diseases. With H/Gs you can't use age as a fair criterion in evaluating the
longevity effects of a Paleo diet (because occupational hazards cut most of
H/G lives far short compared to the protected risk-averse lives of we
moderns). But what you can do is look at the incidence of cancer/CHD as a
surrogate which is about the lowest incidence among humanity documented,
even on an age-adjusted basis. So if you try to be as fair as you can with
the data we do have, H/Gs' extremely low rates of CHD and cancer incidence
is better than what you see in vegans/vegetarians.

Basically what is interesting to see is that the scientific wing of the
vegan camp is coming around to acknowledging that they can't get certain
things in adequate quantities in a vegan diet (B-12 hasn't been an issue
with them for some years now--they admit it; and they admit you really need
to pay attention to zinc, maybe iron, etc.). From this perspective of
course, these diets are certainly not better, they are worse than the
evolutionary diet. The operative phrase, however, is their insistence on a
"well-planned" vegan diet (which more cynically means if you don't really
mind your p's and q's then you are at increased risk). But if a
"well-planned" or "intelligently planned" vegan diet still doesn't do it,
then their fail-safe answer is to simply supplement those things, while
they still hold to the idea a vegan diet is superior in other ways. (Of
course some people simply fail to thrive, supplementation or not, which is
another thing conveniently ignored by most vegans in this "improvement over
evolution" idea.)

And now the EFAs, DHA issue is just barely starting to surface in the vegan
world with lots of rationalizations still. But even if the vegan world
acknowledges it eventually, the recommendation will still simply be to
supplement it artificially. All of this brings up the question, though, of
how far away from a natural diet and how many hoops you want to have to
jump through via the artificial/substitution approach, to what extremes you
want to take it to prove a point of some sort, and what kind of life you
want to live.

There are some good lessons for paleo people here, though, too. Not
everyone can afford a full paleo implementation even they wanted to. With
the way society is going, we may all have to utilize the "substitution"
approach to a degree, using the evolutionary past as simply a template of
nutritional balance (rather than an absolute god to mimic) to do the best
we can with what we have available today, and not worry too much about
being purists about it ourselves.

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