WebMD Now: Are GMOs Safe?

Cereal for breakfast, salad for lunch, cookie for a snack? Chances are, you've eaten a GMO food today. They're found in 80% of packaged foods in the US and in crops such as corn, soy, zucchini, and yellow summer squash. GMO stands for Genetically Modified Organism, but what is that exactly? Basically, it's any plant or animal whose DNA has been changed in a lab. It's done to help crops hold up against disease and to resist pests. Food can also be enhanced to have more nutrients or a longer shelf life, and they can help farmers grow more food.

Sounds great, right? So why such a fuss? Well, some people worry that GMOs create Frankenfoods that makes them unsafe to eat. But so far, there is no evidence that these foods cause any health problems. Each of these GMOs is evaluated by the FDA and must meet all the same requirements as traditionally grown food.

Another concern? What are they doing to the environment? See, these plants are engineered to survive being sprayed with herbicide, which kills the weeds around them. But there's a concern that the weeds could build a resistance and also survive being sprayed, which means farmers may have to use more and more herbicide. Some data suggests that this is already happening.

If you do decide you'd rather be GMO-free, there are ways to avoid them if you keep your eyes peeled. Mostly they're found in processed foods. Right now, most fresh produce isn't GMO, though dairy, beef, chicken, and pork could be from animals that ate GMO feed, so check the labels. Some food producers do label their foods, so look for fresh, whole, unprocessed foods marked as Non-GMO or Certified Organic or USDA Organic. Organic foods can't have any GMOs. So when in doubt, read the label.