The U.S. Department of Agriculture has specific guidelines that food producers must comply with if they want to use the "organic" label. Animal products cannot be given antibiotics or growth hormones, and plants cannot be grown with conventional pesticides or fertilizers made with synthetic ingredients or sewage. Genetic engineering and irradiation, exposing crops to radiation to kill bacteria and other pests, are also prohibited for plants to be considered organic.
There are three levels of organic to look for in stores. "One hundred percent organic" means products are made entirely from organic ingredients, "organic" means that at least 95 percent of a product's ingredients are organic, and "made with organic ingredients" indicates that at least 70 percent of ingredients are organic. While going organic may be better for the environment, Frechman says it's "not necessarily" the healthier option. "The science is mixed," she says.
According to the FDA, food items labeled "fresh" must be raw or unprocessed, and never have been frozen or heated. They also cannot contain any preservatives. However, "fresh" does not mean that fruits and vegetables have been picked recently, or that animals were killed at a certain time. As Frechman says, "fresh" produce may have bacteria from sitting in a store or on a truck for a long time, so make sure you wash all fruits and vegetables.
Genetically modified foods—whose DNA has been altered with the help of modern technology—do not have to be labeled, though their safety is still up for debate in the scientific community. (According to the World Health Organization, "GM foods currently available on the international market have passed risk assessments and are not likely to present risks for human health.") The majority of corn and soy—primary ingredients in junk food—are genetically modified, so researchers estimate that 70 percent of all processed foods contain some genetically modified ingredients, though you wouldn't know it to look at the packaging. The only way to avoid genetically modified foods is to buy 100 percent organic. But be on the lookout for new policy changes—a California ballot measure will ask voters in November whether the state should require that all genetically modified foods be labeled.