"GMO" stands for "Genetically Modified Organisms," and in the case of food, it usually refers to foods that have been genetically engineered for reasons unrelated to health or nourishment. You may also see the term "GE foods" (which stands for "genetically engineered" foods) or terms like "genetically altered" or "genetically modified" or "genetically improved" to describe these foods.
The process of genetically modifying foods is relatively new to the world of agriculture. In 1994, no GE food crops had been planted in the United States. Today, more than 165 million acres are planted each year. The Center for Food Safety, a non-profit public interest and environmental advocacy group headquartered in Washington, D.C., estimates that 70-75% of all grocery store products contain at least one genetically modified ingredient. You have almost certainly already consumed many GE foods, whether you knew it or not.
The health risks associated with GE foods have not been clearly identified. Given their meteoric rise within the food supply, little research has been done to determine their potential health risks. Since genes are the blueprint for making proteins, GE foods by definition contain novel proteins that were not present in the food prior to its genetic modification. Since proteins are often the basis for an allergic food reaction (our immune system will sometimes make antibodies to help neutralize proteins that are interpreted as being potentially dangerous to our health), many scientists have speculated that novel proteins in GE foods may cause these foods to trigger allergic reactions more frequently than their non-GE counterparts. Additionally, some scientists believe that the altered genetic and protein composition of GE foods may present problems for various regulatory systems in the body - including the immune and inflammatory system - and may cause disruption in cell signaling or in digestive tract function.
According to 2010 data from the U.S. Department of Agriculture, just over 90% of all U.S. soybeans, 90% of U.S. sugar beets, and 85% of U.S. corn crops are genetically modified. (Because many foods contain cottonseed oil, it's also worth noting that 90% of U.S. cotton crops are also genetically engineered.) This very high percentage of genetic engineering in the production of corn, soybeans and sugar beets greatly increases exposure to GE foods among U.S. consumers since processed components from these foods are found in so many processed and prepackaged products.
For corn, of course, the most common processing product is HFCS, or high fructose corn syrup. This product is found in literally thousands of processed foods, including sodas, baked goods, and many other foods. Other processed food ingredients that often come from corn include corn syrup, corn syrup solids, malt, maltodextrin, maltose, maltol, ethyl maltol, malt syrup, mannitol, dextrose, dextrin, and polydextrose. Of course, corn starch, corn flour, and corn oil are also corn-based ingredients. When produced in the U.S., all of the above ingredients are likely to have originated from genetically engineered corn, unless specifically certified as organic. (Genetic engineering is not allowed in the production of certified organic foods or food ingredients.)
As one of the most common GE foods in the U.S., soybeans can be even more difficult than corn to identify in processed and prepackaged foods. The list of processed food ingredients derived from soybeans is a long one and includes: hydrolyzed vegetable protein (HVP), textured vegetable protein (TVP), textured soy protein (TSP), textured soy flour (TSF), lecithin, meat analogs, isolated soy protein, isolated vegetable protein, soy protein concentrate, and structured protein fiber (SPF). Of course, soy bran, soy fiber, soy nuts, soy oil, soy sauce, soy grits, soy meal are also made from soybeans. When produced in the U.S., all of the above ingredients are likely to have originated from genetically engineered soybeans, unless specifically certified as organic. (Genetic engineering is not allowed in the production of certified organic foods or food ingredients.)
While the rise in genetic engineering of soybeans and corn has been relatively steady over the past 10 years, the rise in genetic engineering of sugar beets has been much sharper and more recent. Sugar beets currently supply approximately half of the processed sugar added to prepackaged foods in the U.S., and the vast majority of sugar beet seeds sold in the U.S. are genetically engineered seeds. Beet sugar is found in a wide variety of different processed foods, including cereals, baked goods, beverages, cereals, and candies. Chocolates are also sometimes sweetened with beet sugar. When produced in the U.S., beet sugar that is listed in the ingredients of any product above is likely to have originated from genetically engineered sugar beets, unless specifically certified as organic. (Genetic engineering is not allowed in the production of certified organic foods or food ingredients.)
Since the U.S. National Organics Program forbids the use of genetic modification in foods to be certified as organic, purchasing organic is a great way to lower your exposure to GE foods.
Unfortunately, no mandatory labeling laws for GE foods exist in the United States, even though England, France, Germany, New Zealand, Switzerland, China, Indonesia, and over 25 other countries require labeling of GE foods. (Certain GE food crops are actually banned in some countries, including England, Japan, Brazil, Norway, India, and Thailand). In the United States, the U.S. Food and Drug Administration (FDA) has generally discouraged the use of terms like "GMO-free" or "non-GMO" on food labels and has expressed concern about these terms as being misleading. From the FDA's perspective, any statement that implies superiority of a "GMO-free" food is misleading because they note that there is no scientific evidence to support any increased health risks associated with GE foods. While we agree that scientific studies are sadly lacking in this area, we also believe that GE foods can logically be expected to bring with them added health risks, and we would like to see all GE foods and non-GE foods clearly labeled for this reason. However, until such labeling is widely adopted, the only practical way to lower GMO risks is to select certified organic foods.
Center for Food Safety. (2008). Genetically engineered food. Campaign report available online at: http://www.centerforfoodsafety.org/campaign/genetically-engineered-food/crops/
Center for Food Safety and Applied Nutrition (CFSAN). (2001). Guidance for Industry: Voluntary Labeling Indicating Whether Foods Have or Have Not Been Developed Using Bioengineering; Draft Guidance. U.S. Food and Drug Administration (FDA), U.S. Department of Health and Human Services (DHHS), Silver Spring, MD.
Economic Research Service. (2011). Adoption of Genetically Engineered Crops in the U.S. National Agricultural Statistics Service (NASS) Data Set, U.S. Department of Agriculture, Washington, D.C.
Fernandez-Cornejo J and Caswell M. (2006). The First Decade of Genetically Engineered Crops in the United States. U.S. Department of Agriculture Economic Research Service, Economic Information Bulletin No. (EIB-11) 36pp. Available online at: http://www.ers.usda.gov/Publications/EIB11/.
Pew Initiative on Food and Biotechnology. (2004). Genetically Modified Crops in the United States. Pew Charitable Trusts, Washington, D.C. Available online at: http://www.pewtrusts.org/news_room_detail.aspx?id=17950