If something is labeled "organic," (such as edamame or corn chips), can it contain GMO soybeans or corn?
— Diane T., via email
The simple answer is: No — so long as the organic designation is certified by the U.S. Department of Agriculture. Purchasing certified-organic foods is the main safeguard against consuming genetically modified organisms, GMOs for short.
Genetic engineering is the science that creates GMOs by inserting DNA from one species into a different — usually entirely unrelated — species. Among the most infamous examples is the splicing of salmon-scale genes into tomato DNA to yield fruits with stronger skins.
Anti-GMO sentiment in the mid-1990s influenced the USDA's decision to disallow GMOs in organic foods.
It is possible, however, to purchase products that are not certified organic but guaranteed to be free of GMOs. Tofu, for example, is made from soybeans, very often a genetically modified crop in the United States. Tofu manufacturers recognize that while consumers may not choose a bean curd because it's organic, they do want one that doesn't contain GMOs.
Scientists say their work yields foods that are easier to grow, more productive, resistant to disease or spoilage or just more visually appealing. These traits usually cannot be imparted through traditional plant-breeding methods and often involve the use of bacteria or viruses.
GMO proponents also argue that manufacturers are ensuring a stable food supply. Opponents argue that genetic engineering was not adequately tested before entering the U.S. food supply, so there's no way to know the long-term effects of GMO consumption.