Dean writes:
>Eaton, Shostak, and Konner also seem to feel (in this particular book)
>that honey is an important source of dietary carbohydrate, and use this in
>part to justify a recommendation that a majority (60%) of daily calories for
>modern humans should come from carbohydrate. But this seems absurd;
>while I am quite certain that honey would be prized as a delicious treat by
>most any primitive peoples, it seems awfully unlikely that braving wild bee
>nests just to obtain a few ounces of honey would ever be a daily ritual.
>It also doesn't seem that there would be enough beehives with enough honey
>to make the stuff more than an occasional treat even if braving bees nests
>were trivial.
I understand that Dr. Janette Brand Miller is now a part of our group.
She has recently written an article on the role of honey in
pre-industrial diets (Allsop KA, Brand Miller J. Honey revisited: a
reappraisal of honey in pre-industrial diets. Perhaps she can comment
upon Dean's remarks.
Dean makes the comment:
>Yet this all seems odd; what form of wild beans exist and grow in
>such quantities that they could ever be a staple for anybody, and how
>are we to imagine most primitive peoples preparing them? Can they
>realistically be eaten without cooking? What cooking methods would be
>common if so? If beans are natural, why do they cause gas (which
>indicates fermentation of indigestible products in the gut)? If they
>aren't, what are we to make of accounts of the !Kung and other primitive
>peoples who -do- eat them?
Clearly, hunter gatherers have been documented eating legumes, however
under most cases, the legumes are cooked or the tender, early sprouts
eaten raw rather than the mature pod. Some legumes in their raw state
are less toxic than others, however most legumes in their mature state
are non-digestible and/or toxic to most mammals when eaten in even
moderate quantities. I refer interested readers to : (Liener IE.
Implications of antinutritional components in soybean foods. Crit Rev
Food Sci Nutr. 1994 34:31-67; Gupta YP. Antinutritional and toxic
factors in food legumes: a review. Plant Foods for Human Nutrition 1987
37:201-28; Noah ND et al. Food poisoning from raw red kidney beans.
Brit Med J 1980 2:236-7; Pusztai A. et al. The toxicity of Phaseolus
vulgaris lectins. Nitrogen balance and immunochemical studies. J Sci
Food Agric 1981 32:1037-46). These references summarize the basics
about legume indigestibility/toxicity, however there are hundreds if not
thousands of citations documenting the antinutritional properties of
legumes. Legumes contain a wide variety of antinutrient compounds
which influence multiple tissues and systems and normal cooking
procedures do not always eliminate these (Grant et al. The effect of
heating on the haemagglutinating activity and nutritional properties of
bean (Phaseolus vulgaris ) seeds. J Sci Food Agric 1982 33:1324-26).
There are a variety of compounds in beans which cause gas. Mainly,
these are the non-digested carbohydrates, raffinose, stachyose and
sometimes verbascose which provide substrate for intestinal microflora
to produce flatus (Calloway DH et al. Reduction of intestinal gas
forming properties of legumes by traditional and experimental processing
methods. J Food Sci 1971 36:251-55).
Dean states:
>There is also the issue of what are now popularly referred to as the
>"essential fatty acids," the Omega-3 and Omega-6 groups of fats which
>are now acknowledged to be protective against a host of diseases. And
>yet the best sources of the Omega-3 family seem to come almost entirely
>from fish or refined vegetable oils,both of which seem like they would
>be largely unavailable in any great quantity to most primitive humans.
>
>This also brings up the issue of fish, by which I generically refer to
>all freshwater and saltwater fish, including shellfish, eels, etc., as
>well as seaweeds. How natural are these to the human animal? Some
>humans obviously have great access to them, but did we evolve with such
>ready access?
The answer to this one is fairly straight forward. Until about 40,000
years ago, humans rarely exploited the aquatic environment (Eaton SB.
Humans lipids and evolution. Lipids 1992 27:814-20). This inference
can be made by the lack of fossil evidence for fish hooks, weirs,
fishing spears etc; also by the absence of fossilized fish bones in our
ancestors camps. How then did our ancestors acquire N-3 fats unless
they ate foods of aquatic origin? There are different forms of omega 3
fats; the 18 carbon fat (linolenic acid) occurs widely in the plant
kingdom, particularly in green leafy vegetables. The 20 and 22 carbon
omega 3 fats occur almost exclusively in foods of animal origin. Data
from our laboratory shows that the omega 6/omega 3 (N6/N3) ratio for
wild herbivore muscle tissue is between 3-4:1 whereas the lowest
N6/N3ratio occurs in the brain of wild herbivores and is about 1:1.
Because plants contain small amounts of total fats and because their N3
fats (linolenic acid) must be chain elongated and desaturated by the
liver to form the 20 and 22 carbon fats which are essential for cell
structure and function, animal tissues provide a more readily available
source of N3 fatty acids. Muscle and organ tissues of wild animals,
because they provided the majority of the calories for our ancestors
were the environmental template which shaped our present day N3 and N6
requirements. Estimates from our laboratories suggest that the
evolutionary N6/N3 ratio would have been between 2.5 -4.0 which is much
lower than current estimates of 10-15:1 for most western diets.
Cordially,
Loren Cordain, Ph.D.
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