The foods most likely to contain genetically modified organisms include corn, soy, sugar beets, zucchini and yellow squash, according to the Non-GMO Project. Ingredients such as high fructose corn syrup, molasses, lactic acid and textured vegetable protein also frequently contain GMOs.
GMOs are organisms that contain DNA from one or more other species, according to Organic Valley. Common reasons for planting genetically modified crop strains include generating larger yields, improving disease resistance and preserving crops in drought-prone areas. Other GMO crops resist strong pesticides and herbicides. This enables farmers to kill insects and weeds with powerful chemicals without harming the crops.
One way to avoid consuming GMOs is to purchase foods labeled "USDA Organic." Foods with this designation contain no GMOs, preservatives or artificial colors, according to the Organic Trade Association. Organic crops must be grown without synthetic pesticides or irradiation.
Organic labeling regulations also apply to livestock. Certified organic meat must come from animals that were raised on organic feed and were not treated with antibiotics or synthetic hormones, according to the Non-GMO Project.
Farmers, ranchers and food manufacturers undergo rigorous testing to ensure that they remain compliant with federal organic labeling regulations. Compliance verification measures include surprise inspections and contamination testing, according to the Organic Trade Association and the Non-GMO Project.