Genetically engineered foods have had foreign genes (genes from other plants or animals) inserted into their genetic codes.
Genetic engineering can be done with plants, animals, or microorganisms. Historically, farmers bred plants and animals for thousands of years to produce the desired traits. For example, they produced dogs ranging from poodles to Great Danes, and roses from sweet-smelling miniatures to today's long-lasting, but scent-free reds.
Selective breeding over time created these wide variations, but the process depended on nature to produce the desired gene. Humans then chose to mate individual animals or plants that carried the particular gene in order to make the desired characteristics more common or more pronounced.
Genetic engineering allows scientists to speed this process up by moving desired genes from one plant into another -- or even from an animal to a plant or vice versa.
Potential benefits of genetically engineered food include:
More nutritious food
Disease- and drought-resistant plants that require fewer environmental resources (water, fertilizer, etc.)
Decreased use of pesticides
Increased supply of food with reduced cost and longer shelf life
Faster growing plants and animals
Food with more desirable traits, such as potatoes that absorb less fat when fried
Medicinal foods that could be used as vaccines or other medications
Potential risks include:
Modified plants or animals may have genetic changes that are unexpected and harmful.
Modified organisms may interbreed with natural organisms and out-compete them, leading to extinction of the original organism or to other unpredictable environmental effects.
Plants may be less resistant to some pests and more susceptible to others.
Tomatoes, potatoes, squash, corn, and soybeans have been genetically altered through biotechnology. Many more foods have engineered ingredients and more are being developed. Check with the Food and Drug Administration (FDA) for more information.
The Food and Drug Administration (FDA) regulates production and labeling of genetically engineered foods. Some people have raised concerns that the genes from one food that are inserted into another food may cause an allergic reaction. For instance, if peanut genes are in tomatoes, could someone with a peanut allergy react to tomatoes?
In January 2001, the FDA's Center for Food Safety and Applied Nutrition proposed that developers of bioengineered food submit scientific and safety information to the FDA at least 120 days before the food is marketed. Further details on these foods may be found on the FDA website.
Genetically engineered foods are generally regarded as safe. There has been no adequate testing, however, to ensure complete safety. There are no reports of illness or injury due to genetically engineered foods. Each new genetically engineered food will have to be judged individually.
Sudak N, Harvie J. Integrative strategies for planetary health. In: Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 105.
Committee on Identifying and Assessing Unintended Effects of Genetically Engineered Foods on Human Health, National Research Council. Safety of genetically engineered foods: Approaches to assessing unintended health effects. National Academies Press. 2004.
Key S, Ma JK, Drake PM. Genetically modified plants and human health. J R Soc Med. 2008;101(6):290-298.
Jeffrey Heit, MD, Internist with special emphasis on preventive health, fitness and nutrition, Philadelphia VA Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.