Regulators long ago blessed the use of genetically modified organisms to grow such staple foods as corn and sugar beets. Scientific consensus backs the regulators.

But in an age of “Big Food” skepticism, consumers have increasingly become wary of GMOs, the acronym itself striking a menacing tone.

“I am trying to be much more aware of pesticides and GMOs,” said Patty Crater of Edina as she recently left a Cub Foods supermarket. “It’s in the back of my mind all of the time.”

Indeed, a study earlier this year by a prominent research group shows a greater divide on the GMO issue between scientists and consumers than even climate change. The same survey showed 50 percent of consumers look for labels indicating the absence of GMOs.

Food manufacturers are squarely in the middle of the debate. They’re courting consumers’ wariness by increasingly slapping “no GMO” labels on products bereft of the controversial technology. At the same time, they’re quashing efforts for mandatory labeling of food that does include GMO ingredients.

Foodmakers such as Minnesota’s General Mills, Hormel and Land O’Lakes have spent tens of millions of dollars to fight mandatory labeling, winning a victory last week when the U.S. House passed a bill that forbids states from forcing companies to add to labels when ingredients are GMO.

While the Republican-backed bill killing mandatory GMO labeling clearly gives the food industry what it wants, how much it actually threatens consumers is not clear at all.

“My constituents, like most Americans, have no idea what a GMO is,” Rep. Collin Peterson, D-Minn., said recently. “It’s a term created by the green movement in Europe to give a bad name to something.”

Are the GMOs safe?

GMOs are common in the nation’s farm fields.

At least 90 percent of U.S. corn, soybean, sugar beet and canola production comes from seeds that have been genetically modified in order to better kill insects and weeds. These crops provide a bevy of ingredients for processed foods. The result: 70 to 80 percent of the food most Americans eat contain some ingredients ultimately derived from GMO seeds.

Supporters of mandatory GMO labeling, like scientist Doug Gurian-Sherman of the Center for Food Safety, argue that GMO safety research has been “oversimplified” and that “there has been no epidemiological testing on GMO foods.”

But groups such as the National Academy of Sciences, the American Medical Association and the European Commission agree that GMO foods are safe.

A gaping divide separates public perception of GMO foods and researchers’ reality. A 2015 survey by the Pew Foundation found that 88 percent of the largest group of U.S. scientists — the American Association for the Advancement of Science — believe genetically modified foods are “generally safe.” Just 37 percent of U.S. adults do, the survey found.

The gap between scientists and the public over GMOs was wider than in six other prominent science issues, including climate change. Two-thirds of the public believes scientists don’t have a clear understanding about the health effects of GMO crops, according to the Pew study.

Supporters of mandatory GMO labeling released a survey in anticipation of last week’s House vote and in Minnesota, 84 percent of those surveyed favored labeling GMO foods.

Involving government

Consumer suspicion about GMOs is part of a backlash against conventional food production, from qualms about artificial colors to antibiotic use in food animals.

“It’s the age of transparency,” said Melissa Abbott, culinary insights director at the Hartman Group, a market researcher. “The consumer is really scrutinizing food companies more than ever before.”

GMO awareness took off in 2012, Abbott said, when California had a referendum to require mandatory labeling of food with GMO ingredients. The effort failed, but “the California vote did really bring [GMO labeling] into the mainstream,” she said.

Similar mandatory-GMO referendums have since also failed in Washington, Oregon and Colorado. But in 2014 the Vermont legislature voted for mandatory GMO labeling in 2016. Maine and Connecticut also passed measures, although they would only kick in after a minimum number of other states also have passed GMO laws. The bill passed by Congress this week would prohibit all state efforts, which the food industry argues creates a costly crazy quilt of regulation.

Records examined by the Star Tribune show that General Mills, Land O’Lakes, CHS Inc., Hormel and Schwan Food each spent money lobbying for the House to pass the bill. Trade groups representing those companies and several other state businesses chipped in more.

Nationwide, supporters of the bill outspent opponents $30 million to $10 million, according to the open records group Maplight.

Food companies react

As attention to GMOs has grown, so have efforts to market products calling out their absence.

In 2010, only 1.6 percent of new food and drink products made “non-GMO” labeling claims, according to Mintel, a consumer researcher. By 2012, that number had climbed a bit to 2.8 percent. But after the fanfare of GMO labeling referendums, 10.2 percent of new products were launched with non-GMO claims in 2014.

That was almost as many as the number of new products making “organic” claims in 2014, according to Mintel. Organic food by nature is non-GMO, but it’s also raised under stringent federal guidelines on pesticide and fertilizer use. Unlike the “organic” label, non-GMO hasn’t been defined by the U.S. Department of Agriculture. It would be by the law that passed the House last week.

A non-GMO label developed by a nonprofit group — and involving testing the products — has taken off as a marketing tool for food makers. Since the label launched in 2010, the Non-GMO Project has verified close to 35,000 products, including 10,000 just this year.

The group has reviewed 1,500 brands, working with “mom and pop” foodmakers to large packaged-food companies like PepsiCo, Kellogg Co., and General Mills, said Courtney Pineau-Bos, the Non-GMO Project’s associate director. “Everyone is feeling the demand.”

General Mills has particularly made use of the Non-GMO Project label, affixing it to about 200 products under brands such as Annie’s, Cascadian Farms, Muir Glen and Larabar. At least 150 of those items are also organic, and sport the USDA’s “organic” label.

Some products, such as popcorn, that have always come from non-GMO sources but never bore a label are now being marked, for example, ConAgra Foods’ Orville Redenbacher popcorn (the traditional, non-microwave variety).

Non-GMO is becoming a new “tier” within the packaged-food market, said Hartman’s Abbott. It’s the new “natural,” but without that controversial food claim’s negative side, she said.

The widely used “natural” label is so ambiguous that it’s sparked a raft of lawsuits against foodmakers. “Even though there is no government standard, non-GMO is very specific,” Abbott said.

Issue likely won’t die

Sixty-four other countries have mandatory GMO labeling provisions that allow shoppers to make a choice, said Gary Hirshberg, the retired CEO of Stonyfield Farm and chairman of the advocacy group Just Label It. You can be “agnostic” about GMO safety and still make a case for doing the same thing in the U.S., he said.

“I look for GMO labels,” wrote Anne Griffin-Lewin on the Star Tribune’s Facebook page. “I don’t know if GMOs are good or bad. I suspect it is some of each.” But, she added: “I think they should be labeled so we can all make informed decisions.”

Griffin-Lewin was one of dozens of readers responding to a query posted by the Star Tribune on GMOs and GMO labeling. Many agreed with her. But several others labeled mandatory GMO labeling as simply pandering to anti-science sentiment.

“The labeling is useless,” wrote Kristin Dittmann. “Food and drug labeling is done for a reason, and GMOs aren’t specifically harmful.”