About 20 years ago, a company now owned by Monsanto (MON) introduced the Flavr Savr tomato -- the first genetically modified organism approved for consumption in the United States. Since then, farmers across the country have been using more and more GMOs every year.
It's a practice that has come under increasingly intense scrutiny. Activists who are worried about the potential for human health problems, as well as environmental damage, have started demanding that food containing GMOs be labeled as such.
Prop 37, a California ballot measure to mandate GMO labeling, failed at the polls in 2012, and a similar measure lost last month in Washington state. In both campaigns, the largest makers of GMOs -- Monsanto, DuPont (DD), and Dow Chemical (DOW) -- provided the ad funding that helped turn the tide.
But what many people don't realize is that they've been consuming products with GMO ingredients for years.
The Institute for Responsible Technology has a brochure breaking down GMO presence in many different types of foods. Here are 10 of the most popular foods that likely contain GMOs.
10 Foods You'll Have to Give Up to Avoid Eating GMOs
Pre-made soups can contain a large number of ingredients containing GMOs. For instance, Campbell's (CPB) popular condensed Tomato Soup lists high fructose corn syrup as its second biggest ingredient. According to the Non-GMO Project, nearly 88 percent of all corn planted in the United States is GMO.
It doesn't stop at HFCS, though. Take the company's Cream of Mushroom soup, which lists vegetable oil as its third ingredient. It specifically says the oil does come not only from corn, but from cottonseed, canola, and/or soybeans. However, in America, says the Non-GMO Project, 90 percent of cottonseed, 90 percent of rapeseed (the source of canola), and 94 percent of soybeans are GMOs.
Frozen foods are often sweetened with HFCS, according to IRT. And even if HFCS isn't on the ingredient list, the presence of non-cane sugar likely means GMOs are included. Sugar beets provide half of all consumable sugar in America, and 95 percent of those sugar beets are grown using GM seeds, according to the Non-GMO Project.
Many parents might be surprised to find out they've been feeding their infants GMOs. Both milk and soy products regularly show up the ingredient list for baby foods. In America, according to the Non-GMO Project, 94 percent of all soy is GM. Meanwhile, 88 percent of the corn fed to cows contains GMOs, meaning that such organisms are part of the food chain that ends with milk being produced and fed to infants.
If you didn't expect juice to make this list, that probably means you know a little something about GMOs: The Hawaiian papaya is the only genetically modified fruit readily available to average American consumers. The vast majority of fruits are don't have GMO variants in the marketplace. But in order to entice kids to drink more juice, many companies add HFCS or non-cane sugar. For instance, Minute Maid -- owned by Coca-Cola (KO) -- offers a 20-ounce bottle of fruit punch that has HFCS as the second largest ingredient and contains 71 grams of sugar.
The chances are fairly slim that you'd encounter GMOs when dealing strictly with grains (other than corn) in their natural grainy state. But when you're eating cereals, especially those made for children, there's much more than just grains in your bowl. General Mills' (GIS) Honey Nut Cheerios -- America's top-selling brand -- has sugar and corn starch listed as two of the top three ingredients -- both likely to contain GMOs.
Vegetable oil can be made from several different plants. Some of the most popular are corn, soy, and cottonseed. All three of these crops -- when sourced from the United States -- have a greater than 88 percent chance of being GMOs, according to the Non-GMO Project. Canola oil's parent plant -- the unfortunately named rapeseed -- is also highly likely to be a GMO, as 90 percent of all rapeseed plants from the United States come from GM seeds.
It's a favorite of vegetarians, vegans and other healthy-eating enthusiasts for its high protein content, but the main ingredient in tofu is soy milk, and the vast majority of soybeans from America -- 94 percent -- are GMOs.
We aren't at the point yet where scientists have begun to genetically modify livestock the same way that they have with plants. (Though there was a now-defunct GMO experiment involving pigs dubbed the Enviropig.) But as the saying goes, "You are what you eat." If we take that to heart, then we might view most livestock as simply large GMO consolidators. The main ingredient in the diet of many forms of livestock is corn feed, which usually contains GMO varieties.
Until agribusinesses start genetically modifying the cows, it might feel like a stretch to think of their milk as a GMO product. But since GMO corn feed is the main source of nutrition for dairy cows, consumers should know that GMOs are dominant in the food chain that eventually ends with the milk in your refrigerator, the IRT says.
No type of food is more likely to introduce GMOs into your system than soda. Though our soda consumption has declined, it's still the fourth most popular type of food/drink in the United States. These drinks are pumped full of sugar or -- far more often -- HFCS. And as you know by now, that means they're virtually guaranteed to contain GMO ingredients.
Of course, if any one of these products are marked "USDA Organic" or "Non-GMO," then you know for sure that GMOs aren't present. However, you usually have to pay a premium for such products. For instance, a gallon of standard whole milk runs around $3.29, but its organic counterpart can cost as much as $6.99.
In the end, it's up to each person to determine how important -- if at all -- avoiding GMOs is, and how much you are willing to spend to avoid them.