From The New York Times:
Shoppers who want to know whether they’re purchasing genetically engineered foods do have a few options.
For starters, there is a good chance that any product with soybeans, corn, sugar beets (often used for sweetening) and canola (or canola oil) has G.M.O.s., since genetically modified versions of these crops are so widely planted in the United States.
On the other hand, certified organic produce carrying the green and white circular “U.S.D.A. organic” seal cannot be genetically modified, and organic livestock must be fed only organic ingredients. But processed foods with multiple ingredients can be labeled organic if at least 95 percent of the content is organic.
And a growing number of food producers that don’t use genetically modified ingredients in their products are seeking certification by the Non-G.M.O. Project. They carry a “Non-G.M.O.” label with a logo of a red butterfly on a blade of grass.