In his original (26 May) post with comments to Enig and Fallon
regarding human consumption of saturated fat and the relationship
with CHD, Loren Cordain identified a number of factors in the presumed
paleolithic diet that would have been cardio-protective --
factors that are absent in the typical modern diet.

In his latest post (9 Oct), he elaborated on many of these factors,
and mentioned one other, but only in passing.
So for the sake of completeness, I thought I would mention it:
namely, the high level of SOLUBLE FIBER in the paleo diet.
Soluble fiber has been shown to modify cholesterol metabolism
in ways that can lower serum closterol levels (is its effect
on LDL/HDL known?)

While oat bran was not available to our Paleo ancestors,
they may well have consumed large amounts of soluble fiber
from fruits and veggies. The "typical" late Paleo diet constructed
by Eaton et al. (1) based on diets of modern HGers shows a
daily fiber intake of ~150 g (compared to 20 g for US average),
with much of this coming from soluble fiber.

Among peoples with a higher share of animal food in their diet
than in this typical diet, of course, the level of soluble
(and insoluble) fiber could be much lower.  Which brings me to a question:

Given that levels of insoluble fiber (which promotes bowel
transit time) would be rather low in the diets of
HGers relying heavily on animal foods (and here we could
include Cro Magnon man), one wonders if they had any troubles
with constipation. Perhaps the lack of fiber was balanced
by their high level of physical activity?
But what about in winter, when they are less active and plant
foods are even less available?

Any thoughts/data on this?


(1) Eaton et al., The Paleolithic Prescription, 1988.



Steve Meyers
Staff Scientist
Lawrence Berkeley Lab.
Berkeley, CA