Dr. Clark Spencer Larsen, director of the La Florida Bioarchaeology Project, has proposed a new theory on the demise of some Native American Tribes, based on studies performed on their excavated bones.

Through his research, he has found evidence that some of the tribes of Florida suffered serious and widespread disease, partially due to the fact that their eating pattern shifted after the Spanish arrived. From their previous traditional hunter/gatherer well-balanced diet, rich in seafood and a variety of plants and animals, they changed to a more homogenous diet based almost entirely on corn.

Researchers found much more evidence of anemia, dental cavities, osteoarthritis, bone infections and other problems in the bones of Native Americans who lived after the arrival of Europeans, than in those who lived prior to their arrival.

There are several reasons given by Dr. Larsen for the nutritional problems caused by a corn-dominated diet. First is the fact that corn contains high amounts of sugar, which not only promote cavities, but contributes to poor oral health in general.

Corn is also an inadequate source of protein, usually deficient in 3 of the 8 essential amino acids: lysine, isoleucine, and tryptophan. The 8 essential amino acids are so-named because they must be obtained from the diet, since the body is unable to manufacture them.

Another problem with corn is that it contains significant amount of phytate, which is a chemical that binds to iron and inhibits its absorption by the body. Therefore, a diet high in phytate can make people more prone to iron-deficiency anemia, as well as other problems associated with poor iron status.

Lastly, corn is also a poor source of certain minerals such as calcium and some vitamins such as niacin (B3). Deficiencies of niacin or the amino acid tryptophan can result in a condition known as Pellagra, which is common in corn-eating communities. It can cause a variety of symptoms such as dermatitis, diarrhea, and depression.

Scientific American June 2000; 80-85