Sourced from: Infinite Health Blog, by Dr. Davis,
originally posted on the Wheat Belly Blog: 2012-12-20
Anybody know a Neolithic dentist?
For over two million years, the Homo species
has been a scavenger and gatherer, then a hunter and gatherer.
Homo evolved from the Australopithecines in
eastern Africa, east of the Great Rift Valley. Some 4 million years ago,
4-foot tall Australopithecines, with prognathic snouts, small 450 cc
brains, but the first bipedal (upright) primate, started spending less time
in the trees and more on the ground, consuming a nearly pure vegetarian diet,
existing on a wide variety of wild plants. They likely had large colons and
smaller small intestines to accommodate the large quantity of bowel flora
required to digest the otherwise indigestible polysaccharide fibers of their diet.
The first hominid that most anthropologists regard as
the first Homo species was Homo habilis with slightly
larger brains than Australopithecus, upright bipedal gait, a
probable scavenger of animals. They likely observed the true predators,
the ones with big canine teeth and claws like lions and leopards, tackle
other animals, successfully killing and consuming them. After these
predators were sated, Homo habilis noticed that the skull
containing the brain and the bones containing edible marrow remained,
along with whatever other fragments remained. Our Homo ancestors
therefore scavenged what the true predators left behind. We learned that
stones were useful tools to crack open the skull to access the brain,
or to get the marrow in the bones.
Consuming animal flesh and learning to use tools
as hammers, then knife edges, spears, and hatchets, allowed us to hunt and
kill our own game. The bigger the game, the greater the danger, the greater
the advantage of communication, which led to the development of language
and the uniquely human vocal apparatus. The next Homo species in
the evolutionary sequence was Homo erectus, a wonderfully
successful strain of hominids who became masters of stone tools and the
methods of the hunt, including trapping and herding, with the capacity for
group hunt, cooperation, and communication.
In the evolutionary sequence of the Homo
species, consumption of animal flesh, the development of tools, and the
need for communication and collaboration all led to the progressive growth
of brain size. As brain size increased, pelvic size could not keep pace and
Homo newborns were born incompletely developed, requiring an
extended time after delivery before achieving independence, much longer
than other primates. The prolonged nature of human child rearing enhanced
the enculturation process.
The sequence continues with the evolution of
Neandertalensis and Cro Magnon, the latter being the first of the
Homo sapiens, the forerunners of modern humans, appearing some
180,000 years ago. Brains volumes reached a height of around 1600 cc,
teeth were virtually free of decay and deformity, with consistent evidence
for nutritional adequacy with absence of signs, for instance, of iron
deficiency or malnutrition. (The Wikipedia image at left shows the largest
brained Homo that ever lived, Cro Magnon.) While life for early
Homo certainly had its challenges, such as nematode infestation
from poorly-cooked fish, or traumatic injury (leg fractures were uniformly
fatal), malnutrition was not generally a problem for Homo.
Pre-Neolithic life was, from a nutritional viewpoint, quite good . . .
That is, until around 10,000 years ago when
Homo sapiens first added grains. The
hunter-gatherer cultures of the Fertile Crescent added wild einkorn
and emmer wheat. The inhabitants of southeast Asia added rice that
grew wild. The Native Americans living in the southeastern coastal
North America, MesoAmerica, and the west coast of south America added
maize. The inhabitants of central Africa added millet and sorghum.
(Of course, the timeline of grain incorporation is not quite as clean
as this. Maize, for instance, gathered and then cultivated in what is
now modern Peru something like 4000 years ago. For the sake of
simplicity, we will call it roughtly 10,000 years Before Present.)
What happened to Homo sapiens who added grains? The
anthropologists tell us that grain-consuming Homo:
–Experienced an explosion of tooth decay. While
tooth decay was rare among scavenger-hunter-gatherers, it became commonplace
in grain consuming humans. Tooth decay was accompanied by tooth abscess and
–Shrinkage of the face and jaw–The gruel or porridge tha
t grains commonly yielded meant less dependence on vigorous mastication. As
the face and jaw shrunk, teeth also shrunk but did so inadequately, commonly
leading to tooth crowding (thus braces in kids today).
–Iron deficiency–Anthropologists look for porotic hyperostosis
or cribra orbitalia, skull evidence of inadequate iron intake or overexposure to
blockers of iron absorption (e.g., phytates in grains). (Nematode infestation
can add to the effect.)
–Malnutrition–Evidenced by horizontal ridges in the incisors
and canine teeth.
–Reduction in stature–Height was reduced by several
centimeters. Bone diameter (e.g., femur diameter) was likewise reduced, what
the anthropologists call reduced “robusticity.”
–Reduction in brain size–While the cause-effect connection
is uncertain, roughly coincident with grain consumption, brain size decreased
by 11%–a first in the evolution of Homo.
(Interestingly, the only exception to the above
observations are southeast Asian cultures who consumed rice, arguing that
rice is somehow different.)
That’s as much as can be inferred from the
remains of humans dating back that far. We unfortunately cannot reconstruct
soft tissue diseases like colon cancer, heart disease, or dementia.
Nonetheless, one pattern is clear: When humans first incorporated grains
into their diet 10,000 years ago, corresponding to less than 0.4% of
the time Homo species have walked the earth, we suffered
substantial downturns in health evidenced by tooth decay, deformity,
Ancient grains were an expedient, a convenience,
a dietary patch in times of deprivation, or the means to increased
accessibility that permitted social differentiation away from an
egalitarian society. Of course, these humans consumed wild
grains, not the modern grains that we have today, courtesy of
agribusiness. It’s much worse for us.