“You can’t know for sure if the food you are eating is a product of genetic engineering,” concedes Kathleen Merrigan, PhD, director of the agriculture, food, and environment program at Tufts University Friedman School of Nutrition, Science, and Policy. “Seventy percent of processed food is likely to contain some product of genetic engineering, usually a corn- or soy-based ingredient.”

For now, the best way to avoid GMOs is to seek out organic products. Foods certified by the USDA National Organic Program have been grown from conventional, non-GMO seeds. However, because this program focuses on how foods are grown—not on how they are segregated, transported, or stored—organic crops could very well become cross-pollinated by or commingled with GMO crops.

If you are concerned about keeping organic crops non-GMO, contact your local and state representatives to encourage better legislation to protect them.