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Genetically engineered foods


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 bacteria and other microorganisms. We have bred plants and animals for thousands of years to produce the desired traits. For example, we 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 that gene in order to make the desired characteristics more common or more pronounced.

We have been genetically engineering plants since the 1990s. 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.

Alternative Names:

Bioengineered foods; GMOs; Genetically modified foods


Potential benefits of genetically engineered food include:

  • More nutritious food
  • Tastier food
  • Disease- and drought-resistant plants that require fewer environmental resources (such as water and fertilizer)
  • 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 medicines

Potential risks include:

  • Modified plants or animals may have genetic changes that are unexpected and harmful.
  • Modified organisms may interbreed with natural organisms. This could lead to the extinction of the original organism or to other unpredictable environmental effects.
  • Plants may be less resistant to some pests and more susceptible to others.
Food Sources:

Tomatoes, potatoes, squash, corn, and soybeans have been genetically altered through biotechnology. Many more foods contain engineered ingredients and more are being developed. Check with the Food and Drug Administration (FDA) for more information.

Side Effects:

The Food and Drug Administration 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 sold. Further details on these foods may be found on the FDA website.


In addition to the FDA, the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Agriculture (USDA) regulate bioengineered plants and animals.

Genetically engineered foods are generally regarded as safe. There has not been enough 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.


Food and Drug Administration. Questions & Answers on Food from Genetically Engineered Plants. Last updated July 22, 2014. Accessed Nov. 3, 2014.

Key S, Ma JK, Drake PM. Genetically modified plants and human health. J R Soc Med. 2008;101:290-298.

Sudak NL, Harvie J. Integrative strategies for planetary health. In: Rakel D, ed. Integrative Medicine. 3rd ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 105.

United States Dept. of Agriculture, Animal and Plant Health Inspection Service. Biotechnology. Accessed Nov. 3, 2014.

U.S. Environmental Protection Agency. EPA's Regulation of Biotechnology for Use in Pest Management, May 2014. Accessed Nov. 3, 2014.

Review Date: 10/28/2014
Reviewed By: Emily Wax, RD, The Brooklyn Hospital Center, Brooklyn, NY. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2002 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

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