The debate over genetically modified organisms is heating up. Occupymonsanto.com reports that, in just a single week, more than 60 GMO protests are scheduled to take place surrounding the anniversary of the Occupy Movement, starting September 17. The protests will mark a high point in the past eight months of increasing agitation.

Ever since Proposition 37—a measure that would require mandatory labeling of GMO ingredients—made it onto California’s November ballot, the issue has escalated rapidly. Major food companies are throwing millions of dollars at a campaign to thwart the bill, while less wealthy organizations—the Right to Know Campaign and Non-GMO Project among them—are working furiously to grow awareness where they lack funds.

Both sides say the issue is a matter of access to infomation. Proponents of Prop 37 say consumers have a right to know what they’re eating, while opponents argue that labeling would cause undue panic among consumers, who will misunderstand the labeling.

MORE: 18 Companies That Oppose GMO Food Labeling

In the end, regardless of how labeling laws shake out come November, you’ll decide what you buy and eat. So here’s a quick guide to help you navigate the fraught issue of genetically modified foods.

What exactly is a GMO?

GMO stands for “genetically modified organism” and can refer to plants or animals created by way of gene-splicing techniques. Splicing merges DNA from different species to create combinations that would not occur naturally in nature. Genetic engineering is not to be confused with cross-breeding (the practice of combining, for example, dog breeds).

Biotechnology companies are largely engineering GMO crops to resist direct application of herbicide. This allows the crop plants to live while surrounding weeds die.

Why have other countries banned GMO crops?

More than 40 countries—including all of Europe, as well as Japan and India—have at least some requirements governing the labeling of genetically modified foods. In Europe, labeling laws are strict, and many genetically engineered crops are banned outright.

So what do 40 countries acknowledge that the U.S. doesn’t? One of the most compelling arguments driving labeling laws is that we just don’t know what GMOs are capable of. They’re a relatively recent development in agriculture, and we’ve yet to see their long-term effects. However, animal testing has linked GMOs with cancer, miscarriage, organ damage, and other health problems, which some countries have determined is enough evidence to put on the brakes.

Beyond health effects, genetically modified seeds restrict biodiversity and create hairy situations between organic farmers and those using genetically modified seeds. Genetically modified pollen or even the seeds themselves can drift into organic fields; with patenting laws making it possible for companies to sue farmers who use their seeds without permission, the act of planting crops can become a legal nightmare.

How prevalent are GMOs in the U.S.?

Genetically modified foods make their way into the food system in not-so-obvious ways, such as ingredients in prepackaged foods and as corn syrup in your fruit juice.

The Center for Food Safety breaks it down: 85 percent of U.S. corn, 91 percent of soybeans, 88 percent of cotton (cottonseed oil is in food products), and 95 percent of sugar beets are genetically engineered. Many of these major crops enter packaged foods in various forms. Estimates suggest “upwards of 70 percent of processed foods on supermarket shelves” contain genetically modified ingredients.

While plenty of big food companies are trying to shut down labeling to protect their bottom line, some food companies have come out in favor of labeling, among them Stonyfield Farm, Organic Valley, and Chipotle Mexican Grill, who have signed on to support the “Yes on Prop 37” campaign.

What can I do?

If you want to avoid GMOs completely, the easiest thing you can do is buy certified organic foods and seeds (if you’re growing your own produce). Stringent requirements for organic foods require that, among other things, they cannot be genetically modified.

For other foods that are not produce, such as crackers, noodles, breads, and other processed foods, you need to get a little savvier. “Organic” on a label doesn’t always mean 100 percent organic.

By: Megan Bedard

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