Genetically modified foods have genes from other plants or animals inserted into their genetic codes, according to the University of Maryland Medical Center. Benefits include the ability to create food that has a longer shelf-life and is more disease-, pest- and drought-resistant, which could lead to decreased use of pesticides, water and fertilizers. Foods containing genetically modified plants or animals are not required to be labeled, so it is difficult to identify them. However, the U.S. Department of Agriculture sets the standards for organic foods, and prohibits the use of genetically modified crops in organic farming.
Look for the PLU, or price lookup, code on produce labels. The PLU code for conventional produce has four numbers, genetically modified produce has five numbers starting with the number 8, while organically grown produce has five numbers, starting with the number 9. Look for the number 8 to identify the genetically modified produce.
Read the ingredients of all packaged food to to see whether they contain the top genetically modified plants: soy, corn, canola and cottonseed as well as tobacco, tomatoes, lettuce and wheat. Blended oils made with soy, corn, canola or cottonseed oils, for instance, are most likely made with genetically modified crops, while pure olive oil or walnut oil are not. Genetically modified beets are used to produce almost all of the white sugar in the United States.
Search the Food and Drug Administration, National Research Council, the World Health Organization, the Food and Agriculture Organization of the United Nations, and the Organization for Economic Cooperation and Development websites for information about all aspects of genetically modified crops.
Write to food manufacturers and ask whether the ingredients in their foods are made with genetically modified crops.