The image of a single, wholesome stalk of corn-on-the-cob is as resonant of the country as apple pie. Best of all, the nutritional value of corn, the most quintessentially American of foods, is not only lauded by nutritionists, but is also backed by history. Unfortunately, some fear the health claims of corn may no longer be supported when it comes to the new GMO varieties.
The Story of Maize
Several thousand years ago, Aztec and Mayan Indians in Mexico and Central America domesticated a large, wild grain plant that grew in the area that would eventually become known as "maize." Maize spread to North America over time and the natives there introduced the plant to the European colonists when they arrived; without maize, historians suggest, the Europeans may not have survived the winters of their New World (although the crop the European settlers cultivated would now be referred to as 'field corn'). At the time, only a small amount was eaten fresh — most of the harvest was cooked in fried cakes, breads and puddings, dried for winter storage, or ground into cornmeal and corn flour. Additionally, the colonists used the corn for livestock feed, which is how the variety is used today. Sweet corn varieties were only developed beginning in the 1700s.
According to the Environmental Protection Agency, the U.S. produces more corn than any other country. The "corn belt" — the greatest area of production — is located in the Midwest, includes Iowa, Illinois, Indiana and Ohio. Over the years, cross-pollination during cultivation caused genetic changes that transformed corn into the shape and size we are familiar with today. There are currently thousands of strains of corn, with more than 200 varieties of sweet corn alone. All the varieties, though, can be divided into four basic groups: field corn, sweet corn, popcorn and ornamental corn.
Nutritional Value of Corn
According to the U.S. Department of Agriculture (USDA), one ear of corn provides about 6 percent of the daily requirement of Vitamin C and 10 percent of the daily requirement of fiber. Specifically, corn provides insoluble fiber, which is mainly found in whole grains and vegetables. Corn passes through the gastrointestinal tract relatively intact, and therefore speeds up the passage of food and waste through the gut.
A single ear of corn provides 3 grams of protein, though it is not considered a 'complete protein' with sufficient quantities of all nine essential amino acids. This is easily remedied when corn is combined with beans or another legume, which is how it has and continues to be prepared by many of the native cultures in America.
Corn is also a source of folic acid and niacin. The folic acid provided by a one-cup serving of corn is about 15 percent of the daily requirement. A type of B vitamin, folic acid is responsible for enzyme metabolism and DNA synthesis. The same size serving offers about 12 percent of the requirement of niacin, or Vitamin B3.
Although the above values hold true as of April 2009, when the report was published by the USDA, debate persists regarding the effects of genetic modifications.
The New (GMO) Corn
In 2005, approximately 52 percent of US corn acres were planted using seeds incorporating biotechnology. By 2012, 88 percent of corn grown in the U.S. were genetically modified (GM) strains, according to the U.S. Department of Agriculture. Corn — as well as soybeans, cotton and wheat — has been modified to improve resistance to weeds and insects in order to help farmers boost productivity. Though they pay more to buy GM seeds, U.S. farmers may find them worthwhile; others claim that traditional seeds are not available to purchase and U.S. farmers are forced to accept the GM seeds.
The three main federal agencies responsible for regulating the use of organisms derived from biotechnology are the USDA's Animal and Plant health Inspection Service (APHIS), the U.S. Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA). In 2002, the USDA established the Biotechnology Regulatory Services (BRS) to better regulate field testing, interstate movement, and importation of genetically engineered (bio technology) organisms. BRS evaluates genetically engineered organisms to ensure they are as environmentally safe as their traditionally bred counterparts.
"During 2005, over 1,400 biotech notifications were acknowledged, over 500 permits were approved, and 6 articles were deregulated," states the USDA website.
The USDA's expenditures on research related to biotechnology amounts to about $220 million annually. This division of our government conducts biotech-related research and has also developed DNA markers, software, genome databases, and genetic resources to facilitate crop breeding. USDA's Agricultural Research Service has released more than 400 new crop germplasm lines/varieties since 2000, often in partnership with university and private sector breeders.
Nutritional Value of GMO Corn
In 2009, the International Journal of Biological Science published an article that analyzed blood and organ system data from trials with rats fed three strains of commercialized genetically modified corn. The researchers' analysis revealed new side effects linked with GM corn consumption — specifically, there were issues caused to the kidney and liver, the dietary detoxifying organs. Other effects were noticed in the heart, adrenal glands, spleen, and haematopoietic system.
"We conclude that these data highlight signs of hepatorenal toxicity, possibly due to the new pesticides specific to each GM corn. In addition, unintended direct or indirect metabolic consequences of the genetic modification cannot be excluded," the authors wrote.
The study received a good deal of criticism at the time and some might consider it "debunked." Yet the editor-in-chief of the journal is the well-respected Dr. Chuxia Deng, who is employed by the National Institutes of Health within the Department of Health and Human Services (HHS). Clearly, he as well as the peer scientists who reviewed the article believed this research worthy of publication — none of them have recanted to the article since its publication.
In 2012, Moms Across America, a self-defined "coalition of unstoppable America moms," published a report on their blog which also gave rise to heated debate about GMO products. The 2012 Nutritional Analysis - Comparison of GMO Corn versus Non-GMO Corn was conducted by an independent, outsourced, major food company. According to the analysis, the GMO corn contains a similar amount of nutrients but also a number of elements absent from traditional corn, including chlorides, formaldehyde and glyphosate, and in harmful quantities.
In an article published this year, Cyrus Martin, senior scientific editor at Current Biology, discusses the psychology of the production and consumption of GMO foods. He maintains that the reason GMO food continues to be "unpalatable" to many people in many parts of the world has to do with economics and culture.
"While all of the food safety scares surrounding GM food continue to be debunked as fast as they materialize, there are no doubt potential risks that are not yet fully understood... And there is nothing to say that new varieties of GM food could, in principle, potentially be harmful," he writes. Ultimately, he argues that science marches on.
"On the horizon are GM crops that can grow in inhospitable corners of the earth, such as the dry and salty environs. And we are now seeing the application of GM technology to animals, such as salmon engineered to reach market weight more quickly through the expression of genes encoding growth hormones." He concludes that whether or not these new technologies are adopted widely will depend on the ability of scientists as well as governments to make a convincing case to the public.
de Vendômois JS, Roullier F, Cellier D, Séralini GE. A comparison of the effects of three GM corn varieties on mammalian health. International Journal of Biological Science. 2009.
Martin C. The psychology of GMO. Current Biology. 2013.