I cite empirical evidence that the cultivation of foodstuffs has
> "watered down" the bitter and pungent chemical load, favouring sweet and
> salty tastes.  This has resulted in a diet in contemporary humans, which is
> lacking in these compounds, and therefore lacking in the protection that
> these bitter and pungent compounds provide.
>

Domestication of plants and animals involves selecting for one of the most common forms of
mutation - neoteny.  Neoteny is the retention of juvenile traits into adulthood and results in
the the plant or animal being arrested in its' development.  Thus the thorobred horse looks like
a spindly colt instead of the squat undomesticated horse as pictured in cave dwellings. Corn is
an even better example as it took hundreds of years to discover its undomesticated form growing
wild in Mexico because it so little resembles our corn.

In plants, the fruit growing stage may be prolonged resulting in more carbohydrates and
preventing it from forming chemicals that protect the mature fruit and cause it to drop from the
stalk.  Without neoteny, wheat would have much more tough bran and be nearly impossible to
harvest as it would fall from the stalks onto the ground (domestic wheat requires threshing to
reproduce).

Some of the chemicals lacking in this immature fruit would be used by the plant to ward off
pathogens and parasites that would hinder reproduction.  These chemicals include
antibiotics,anti-fungals and anti-virals.  Mostly, these result in the fruit lasting longer
without spoiling thus enhancing reproductive sucess.

Other chemicals are used by plants to ward off larger animals.  These are also greatly reduced in
neotenized fruit.  Without this effect some common types of modern foods could be hazardous (new
strains of lima beans for instance must be tested for cyanides for this reason).

Compared to the total number of plants in the global biomass, Primates eat relatively few
species.  Vegetable foods edible to humans in nature (i.e. without technology) are edible to all
primates.  Most primates are on the move constantly looking for these plants traveling many miles
surrounded by plants in the rain forest looking for the just right ones.  Tens of millions of
years of evolution have made primates resistant to the toxins these edible plants contain.  They
may even be used by primates to ward off pathogens.  Our primate DNA recognizes them and responds
appropriately.

As well as these toxins, nonedible plants contain non toxic proteins that are not recognized in
the database known as our DNA.  Our bodies don't know weather these are toxins, pathogens or
short term anomolies.  After reaching a threshold of exposure however, the immune system may
mount an attack.  When this attack harms the body itself, you are said to have an autoimmune
disease.

Among paleolithic people who only eat foods edible to primates, autoimmune diseases are as rare
as they are in wild animals (practilly nil).  This is true even for those who eat no vegetables
at all (Inuit).  Among people who get a large part of their nutrition from plants not edible to
othe primates (i.e. grains, beans,potatoes), autoimmune diseases are rampant.  It has been
estimated that 95% of all Americans die of such disorders.

ref:

Ames,B.N. "Paleolithic Diet, Evolution and Carcinogens" Science 238, 1633-34

Budiansky, S. "The Covenant of the Wild:Why Animals Chose Domestication" New York, William Morrow
& Co., 1992

Stahl, A.B. "Hominid Dietary Selection Before Fire" Current Anthropology Vol. 25,No. 2, 4/84

Stefansson, V. "Cancer Disease of Civilization" New York, Hill and Wang,1960


Ray Audette
Author "NeanderThin:A Caveman's Guide to Nutrition"
http://www.sofdesign.com/neander

BTW the earliest example of a cultivated plant (several neatly planted rows - carbon dated to
25,000 years) was of a species of medicinal plant recently aproved for use (by referendum) in
California.