--
---
Barry Groves wrote:

>> Percent mass from meat and fat = 28%
>> Percent mass from plants = 72%
>>
>
> While there would have been regional differences in climate and food supply,
> which today are expressed in racial differences in patterns of such diseases
> as obesity, diabetes and coronary heart disease, these could not have been
> as great as to have provided such a large proportion of plant material to
> constitute 72% mass during the Ice Ages, even if a hominid stomach was able
> to hold such a large volume, which I doubt.

This is a perfect example of the confusion I was trying to clarify. A
percentage of mass is not a mass nor a volume. A diet could have a high
proportion of mass from plants, but that may not actually be an inordinately
large volume or mass of plant food. My example was intended to show that to
be the case. It contained one small sweet potato and about one cup each of
broccoli and blueberries.

As I recall, Dr. Groves recommended something like 20% protein, 60% fat, and
20% carbohydrate, from non-starchy green and yellow vegetables.  If he meant
percentages by calories an example meal would be:

100 g of beef brisket
 35 g of butter
130 g of boiled kale (1 cup)
117 g of roasted carrots (1 cup)

Here's the analysis:

Total calories=587
Macronutrients: 23 g CHO, 39 g Fat, 36 g Protein
Percent of calories: Carb=16%, Fat=60%, Prot=25%

Total weight: 382 g (0.84 lb.)
Percent weight from animal matter: 35%
Percent weight from plant matter: 65%

Here you can see that if you restrict plant matter to green and yellow
vegetables, about two-thirds of the mass of the meal will have to be plant
matter to obtain approximately 16% of calories from carbohydrates.

Four of those meals would provide 2348 calories.

If you add 65 g more butter to this meal to raise it up to 1055 calories,
at that point fat will provide 78% of energy, protein 14%, and CHO only 9%
of calories but of the total 447 g of food, 247 g or 55% will still be plant
matter.

Whether a hominid stomach could hold 447 grams of food I don't know. But the
gut capacity of hominids 2.5 million years ago is immaterial. Cordain's
figures are based on documents of recent hunter-gatherers, not speculations
about hominids 2.5 million years ago. I regularly eat meals of the type I
outlined in my previous post and know for certain that a modern human can
easily consume meals of such proportions without any digestive discomfort.

Moreover, even though Eskimos could have lived on a 100% meat and fat diet,
Weston Price reported that they sought out whatever plant foods they could
get in season, and preserved some plant foods (in fat) for the winter. If
man is designed to be a pure carnivore, why would Eskimos do that?

Dr. Groves wrote: "And even if such uncooked material could have been
digested. We have no dietary enzymes or micro-organisms that will do the job
today. If we had them then, why don't we now?"

Who specified uncooked? Not I. Humans--and here I mean modern homo sapiens
sapiens-- cook foods, both meat and vegetables. This is as true of recent
hunter-gatherers as of civilized man.

Cooking effectively opens plant cell walls to allow our digestive system to
assimilate plant nutrients.  It reduces plant food volume and eliminates the
need for fiber-digesting enzymes or microbes. Moreover meat also is much
more digestible after cooking. Cooked meat is much easier to chew and
cooking denatures the proteins more completely than the stomach's HCl,
rendering the proteins much more vulnerable to hydrolysis by our digestive
enzymes.

I know of no evidence indicating that any known modern human tribe ever
maintained itself on an all raw food diet. Stefansson reported that even the
Eskimos ate much of their food cooked.

In fact, Dr. Richard Wrangham of Harvard has written: "Dental reduction that
accompanied the evolution of Homo ergaster implies that a new and softer
fallback food was then adopted. It seems unlikely to have been raw meat,
because raw meat is difficult to chew and is an improbable fallback food.
Cooked plant food, on the other hand, is a viable fallback food for early
humans because it fits the changes in digestive anatomy and solves the
ecological problems of surviving periods of food scarcity. Living humans
appear unable to live on a diet of raw food in the wild, and the fossil
record suggests that the time when adaptation to a diet of cooked food began
was with Homo ergaster, potentially accounting for various changes in
anatomy and life-history. This analysis suggests that cooking is a core
adaptation in permitting humans to use large amounts of energy despite a
digestive apparatus adapted to soft and easily digestible foods."

I am informed Homo ergaster emerged approx. 1.9 million y.a. If connected to
modern homo sapiens sapiens that would represent some 63,000 generations.



Don