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Genetically modified foods (GMFs)


Also listed as: Genetically modified organisms (GMOs), Genetically engineered foods, GMFs, GMOs
Related terms
Future research
Author information
Labeling requirements

Related Terms
  • Biotechnology, biolistics, canola, corn, crops, DNA, enzymes, genes, genetics, genetically altered, genetically engineered, genetically engineered crops, genetically modified, genetically modified crops, genetically modified nut trees, genetically modified products, genetically modified sweet potatoes, genetically modified rice, genetically modified tomatoes, genomics, protoplast transformation, recombinant DNA, soybeans, vaccines.

  • Since the 1990s, scientists have been able to change the genetic makeup of plants and animals that are used for human consumption. These food products are called genetically modified foods (GMFs), or genetically modified organisms (GMOs). GMFs are produced to enhance or improve the organism's natural traits.
  • In order to produce GMFs, scientists combine genes from different organisms. For instance, researchers have added genes to plants, such as corn, to make them more nutritious or to give them insect resistance. This is done through a process called recombinant DNA technology.
  • Although the terms "genetic modification" and "biotechnology" are often used interchangeably, they are slightly different. Genetic modification specifically involves living organisms, including animals, plants, and bacteria. Biotechnology is a more general term that includes the modification of living organisms, as well as their components, such as enzymes. For instance, biotechnology has been used to create microbes that produce large amounts of enzymes that are necessary for the production of wine, beer, yogurt, and cheese.
  • Many foods in the United States, including corn, soybeans, and canola, are genetically modified. In 2003, it was estimated that about 167 million acres in 18 countries were planted with genetically modified crops. Other genetically modified crops, such as rice with increased iron and vitamins, have been suggested to help reduce the amount of malnutrition in the world, especially in underdeveloped countries. Crops may also be genetically modified so they can withstand harsher temperatures than non-modified foods. As a result, these crops may help provide food to areas of the world where crops are difficult to grow.
  • In addition to crops, animals have also been genetically engineered. For instance, researchers can genetically alter animals, including chickens and cows, to increase their productivity of meat, eggs, and milk.
  • Although researchers believe that GMFs most likely do not have any negative effects on human health, long-term studies are needed to evaluate the safety of GMFs for human consumption.
  • Not all genetically modified plants are grown as food crops. Plants, including trees, have been genetically modified to help reduce groundwater pollution. These plants are designed to reduce the amount of heavy metal pollution in contaminated soil.

  • General: There are four main ways to create genetically modified foods (GMFs).
  • Biolistics: Biolistics has been used to genetically alter plants. It involves directly inserting new genes into the plant. Microscopic pieces of gold or titanium are coated with the new gene and loaded into a cartridge (sometimes called a "gene gun"). The microscopic particles are fired through the plant cells, leaving behind the new DNA. The DNA then combines with the plant chromosomes.
  • Injection: Injections are mainly used in animals. New DNA is injected through a very thin needle into the nucleus of a single cell, usually a fertilized egg that is later inserted into a female uterus. This procedure is often unsuccessful because in many cases, the cells do not express the desired traits of the new DNA.
  • Protoplast transformation: Protoplast transformation is often used to create genetically modified plants. Enzymes are first used to dissolve the cell wall of the plant. This leaves behind a protoplast. Then DNA is added and the cell is grown in a special environment to help the protoplast re-grow cells walls. This new plant is now genetically altered.
  • Vectors: Vectors have been used to create genetically altered plants and animals. Scientists change the genetic makeup of a virus or bacterium so it carries new DNA instead of viral or bacterial DNA. In other words, the disease-causing genes are removed, and new genes are inserted. The vector is then inserted into the organism's cells or tissue.

  • Humans: Although genetically modified foods (GMFs) are widely available in the United States, long-term studies have not been performed to determine the safety of these products. Many researchers have called for well-designed, long-term studies to determine whether or not GMFs have any negative health effects on humans.
  • Preliminary evidence suggests that GMFs may trigger allergic reactions. Researchers speculate that introducing a gene into a plant may create a new allergen, which may cause allergic reactions in sensitive people. Allergic reactions may also be triggered because modified foods contain genes from other organisms that the consumer may be allergic to. For instance, researchers decided against adding a gene from the Brazil nut to soybeans because it is possible that individuals who are allergic to Brazil nuts may have an allergic reaction to the modified soybeans.
  • It has also been suggested that GMFs may damage the body's organs. One animal study found that genetically modified sweet potatoes damage the intestines of rats when compared to rats that received non-modified sweet potatoes. However, researchers claim this study was flawed.
  • Animals: Scientists have changed the genes of animals, including chickens and cows, for many reasons. Researchers have used genetic modification to increase an animal's productivity of meat, eggs, and milk. They have also used it to improve the animals' health and feed efficiency.
  • Crops: Crops, including rice, corn, soybeans, sweet potatoes, apples, tomatoes, cantaloupes, and other fruits and vegetables, have been genetically modified to improve taste and quality (including color and size), reduce maturation time, increase nutrition, increase tolerance to extreme temperatures, as well as to improve resistance to disease, pests, and herbicides.

  • General: Genetically modified foods (GMFs) are produced to enhance or improve the organism's natural traits. Since the 1990s, GMFs have been gaining popularity in the research community and food industry, especially in industrialized countries, such as the United States. According to the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA), there are more than 40 genetically modified plants that have completed all of the federal requirements to be sold in the United States.
  • Socioeconomic: In recent years, GMFs have become increasingly available in developing countries. This is because it has been suggested that these foods may improve nutrition in poor countries with food shortages.
  • Opponents of GMFs argue that the industry will increase developing nations' dependence on industrialized nations because these poor nations rely on the financial benefits of exporting their crops to wealthier nations. They also suggest that industrialized nations, including the United States and many European countries, may exploit the natural resources of poorer, less-developed countries.
  • Ethical: Another argument against GMFs is that artificially altering living things is a violation of natural organisms' intrinsic value. Some individuals believe that changing the genetic makeup of a living organism is morally wrong.
  • As GMFs continue to gain popularity, new laws will be needed to address the ethical and social issues surrounding GMFs.
  • Environmental: Genetically modified crops can potentially infiltrate other non-modified crops that are growing nearby. This can happen when water runs off into nearby crops. It can also occur if the seeds or pollen from genetically modified crops are carried in the wind to neighboring crops.
  • A new type of technology, called terminator technology, has been introduced as a way to restrict the use of GMFs. Terminator technology causes the second generation of GMFs to be sterile. Manufacturers of genetically modified crops can use this technology to protect their products from unauthorized use. However, farmers must buy a fresh batch of seeds each year. Opponents of terminator technology argue that this type of technology could negatively impact the financial livelihood of the poorer farmers. Although terminator technology is not yet commercially available, it is important to note that many countries, including the United States and Canada, have patent laws that prohibit farmers from re-using patented seeds without signing licensing agreements.

  • Although genetically modified foods (GMFs) are widely available in the United States, long-term studies have not been performed to determine the safety of these products.


Future research
  • Humans: Researchers are looking into ways to produce vaccines through genetically modify foods (GMFs). For instance, researchers are trying to develop bananas that produce human vaccines against infectious diseases, such as hepatitis B. Researchers are also working to develop vaccines in other plants, including tomatoes and potatoes. Scientists hope that these plants will be much easier to ship, store, and administer than traditional vaccines, which need to be refrigerated.
  • Animals: Researchers are also trying to produce genetically modified fish that mature more quickly than normal.
  • Crops: Scientists are currently working to produce fruit and nut trees that grow their nuts years earlier than normal.

Author information
  • This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (

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Labeling requirements
  • In January 2000, an international trade agreement for labeling GM foods was established. More than 130 countries, including the United States, which is the world's largest producer of GMFs, signed the agreement. The policy states that exporters must label all GMFs so that importing countries can decide whether or not they want to purchase the products.
  • Once a country purchases imported GMFs, that nation can decide whether or not to label the products.
  • Currently, GMFs that are sold inside the United States do not have to be labeled as genetically modified. This prevents consumers from making an informed decision about many of the foods they eat.
  • In contrast, all of the European Union nations, as well as Australia, China, Japan, New Zealand, and several other countries, require that foods that are made with genetically modified ingredients are labeled.

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The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.

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