DNA Proves Humans Designed as Starch Eaters

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DNA Testing Proves Humans Are Designed as Starch Eaters

 

Diet and the evolution of human amylase gene copy number variation by

George H. Perry published in the October 2007 issue of Nature Genetics

found that there are more copies of genes that produce

starch-digesting enzymes, known as amylases, in the human saliva than

there are in lesser primates. The average human has roughly

three times more copies of the salivary amylase genes than do

fruit-eating apes and monkeys. Even among humans the number of

copies was dependent upon the amount of starchy vegetables in their

respective diets. For example, populations who eat more starch (such

as rural Japanese) were found to have more copies than do people

living on lower starch diets with meat and fish added (for example,

Yakut of the Arctic). These findings confirm the predominant

importance of starchy vegetables and grains in the human diet.

 

(Amylases are enzymes secreted by the salivary glands and pancreas to

break down starches into maltose-a double-sugar made up of two

glucose molecules-and dextrin. The genes that produce amylase are

not present at all in the saliva of carnivorous animals, such as cats,

because these animals are not supposed to eat starchy vegetables.)

 

Comment: The researchers begin their article by noting,

"Starch consumption is a prominent characteristic of agricultural

societies and hunter-gatherers in arid environments." Recorded

human history tells of most populations living on starch-based diets.

Some examples are the ancient Egyptians who lived on wheat, the Incas

who lived on potatoes, the Aztecs and Mayans who lived on corn, and

the Japanese who lived on buckwheat and later rice. The

few peoples who have based their diets on meat have lived at the

extremes of the earth's environment, such as the Eskimos in the

Arctic and a few small gatherings living deep in the jungles of South

America and Africa.

 

These researchers reasoned further that starchy foods, like tubers,

were crucial to the successful evolution of early humans, because

starches offer important advantages. Their abundant,

readily-available calories provide for the energy required for the

evolutionary enlargement of our brains. The modern human brain uses

20% of our daily calories, and the preferred fuel for the brain is

glucose, derived most efficiently by digesting starches. With

attainment of the knowledge of the use of fire, which occurred

concurrently with our brain development, starches became a goldmine of

brain-feeding calories.

 

The ability to use starch also opened up the opportunity for early

humans to migrate out of Africa-to colonize of the rest of the

planet. Starches were widely distributed geographically and easy to

gather-tubers, like potatoes, are easily dug up out of the ground.

Bulbs, corms, and tubers act as underground storage units for

concentrated starches and last in the ground throughout the winter.

These starches were a critical food source for the ancestors of

early and modern humans. Once harvested, starches, such as potatoes

and grains, can be stored at ambient temperatures for long periods of

time-providing nutrition throughout the year. Fruit eating would not

offer these advantages because fruits are relatively low in calories,

spoil quickly, and in the more northern and southern latitudes fruits

are available only seasonally. Primates who live on fruit diets are

tied to the tropical jungles.

 

Proponents of meat-based diets preach that the introduction of meat

into the human diet was responsible for the evolutionary development

of the human brain. One of this study's principle

authors said this theory is improbable. Nathaniel Dominy pointed

out, "Even when you look at modern human hunter-gatherers, meat is a

relatively small fraction of their diet. They cooperate with language,

use nets; they have poisoned arrows, even, and still it's not that

easy to hunt meat. To think that, two to four million years ago, a

small-brained, awkwardly bipedal animal could efficiently acquire

meat, even by scavenging, just doesn't make a whole lot of

sense."

 

Before the availability of DNA testing many other observations have

proven we are designed to be primarily plant-eaters. Our teeth

are for grinding, not the tearing of animal flesh. Our

intestines are long and convoluted for digestion of fibrous

plant-foods; meat-eaters' intestines are much shorter and relatively

simple for quickly digesting and eliminating the digested flesh.

For a more complete discussion of our anatomy and physiology which

establishes us as primarily plant-food eaters see my July 2003

newsletter: Meat in the Human Diet.

 

Through the modern science of DNA we have discovered an essential

truth locked in our genes: humans are starch eaters. The failure

to abide by this truth has resulted in unprecedented human disease due

to malnutrition from over-nutrition, and an impending environmental

collapse from the livestock industries supporting Western people's

perverse diet. Applying correct information about human

nutrition results in miraculous cures of dietary diseases (for

example, obesity, type-2 diabetes, inflammatory arthritis, and the

ravages of atherosclerosis). The eventual return of humans to

their starch-based diet will be a huge step in solving our

environmental crises, as well.

 

Perry GH, Dominy NJ, Claw KG, Lee AS, et al. Diet and the evolution of

human amylase gene copy number variation. Nat Genet. 2007

Oct;39(10):1256-60. Epub 2007 Sep 9.