As you carefully provide your kids with energy-boosting breakfasts, picky-eater-proof lunches and balanced dinners, do you really know what’s in the foods you’re offering? Do you know, for instance, that GMOs are prevalent in our food system? Further, do you know what a GMO actually is? One dad went on a cinematic quest for these answers and more.

In the new documentary GMO OMG, which opens in theaters September 13, Jeremy Seifert explores the omnipresence of GMOs—genetically modified organisms; plants or animals produced through techniques of biotechnology—and the uncertainty of feeding his three young children lab-altered foods. What he learns: Most of the food we eat contains GMOs: wheat, corn, even livestock such as beef and chicken (animal feed contains GMOs). Virtually all commercial farms in this country use genetically modified seeds simply because they yield a larger crop—the plants’ engineered herbicide resistance enable farmers to spray swathes of land with chemicals that kill weeds but won’t kill crop, and their internal pesticide production wards off preying insects.

These GMO crops provide the raw ingredients that go into the food at restaurants, including fast-food chains, and grocery stores, including health-oriented markets. By some estimates, 80 percent of the packaged food in the United States and Canada contains genetically engineered ingredients. GMOs are everywhere; in one scene, Seifert discovers that the fish his children catch in a remote campsite stream are fed pellets containing GMOs. The big catch: the FDA does not require genetically engineered food to be labeled as such (though some companies test and label as non-GMO voluntarily), and the jury is out on the health risks of consuming these foods.

Norway, Austria, Germany, the United Kingdom, Spain, Italy, Greece, France, Luxembourg, Portugal, Thailand, China, Japan, the Philippines, Algeria, Egypt and Australia have all placed restrictions on, if not outright banned, the cultivation and distribution of GMOs. The U.S. does not even require foods containing GMOs to be labeled.

Though GMO crops are a quick fix for large yields, Seifert learns they may not be sustainable. He visits the Rodale Institute Farm, where no GMOs are used. The farmers there explain that GMO farming is effective only until weeds and pests become resistant to the herbicide and insecticide the crop is genetically modified to produce. In the long run, organic farms produce comparable yields to commercial farms, and even larger yields in times of drought or other weather crises.

Seifert also visits France to discuss a study conducted there on the effect of GMOs on lab rats. The results are troubling: Female rats fed a diet of GMO corn grew massive tumors and males experienced liver failure and increased hormone levels. The control group fed a natural diet did not exhibit these health problems.

“Where is the outrage?” Seifert asks in this eye-opening film. Squelched by big agricultural biotechnology corporations, he suggests. Monsanto, one of these corporations, spends millions of dollars to stop anti-GMO campaigns and research initiatives against GMOs like the study in France. And representatives from corporations like Monsanto refused to speak with him.

At the start of GMO OMG, Seifert asks passersby in his neighborhood whether they know what GMOs are. The majority of them do not. Once Seifert explains what they are, nearly all agree that states should label GMOs and restrict the cultivation of GMO crops. The film pulls no punches in its plea that Americans must educate themselves on GMOs and possible risks. At the very minimum, don’t we have a right to know what we’re feeding our children?

For more information, visit gmofilm.com and nongmoproject.org.