Fear Factor: The Truth About Genetically Modified Foods

Consumers don’t always know whether their food or beverage contains genetically modified ingredients, and hundreds of groups are calling for mandatory labels. However, almost all major medical groups and independent scientists say GMO labels aren’t necessary.

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Next to the nutrition information label that’s on all packaged foods that are in your grocery store, you might find a new label—“non-GMO”—which typically is accompanied by an illustration of a butterfly on a leaf.

The voluntary label is at the heart of a nationwide battle over what it means for a food to contain genetically modified organisms (GMOs) and whether companies should be required to tell consumers about the technology that’s used to produce their food.

Hundreds of pro-labeling environmental groups, organic-food manufacturers and activist organizations, such as Center for Food Safety, Greenpeace and National Organic Coalition, focus on the potential health risks of GMOs and argue for transparency in the food industry.

In the past 5 years, the Non-GMO Project, which is an 11-year-old organization that verifies beverages and foods that contain no more than 0.9 percent GMOs, verified almost 35,000 products.

Some major grocery stores and national restaurant chains are jumping on board, too. Chipotle eliminated most GMOs from its menu in 2015, and Whole Foods committed to label all genetically modified foods that are on its shelves by 2018.

In July 2016, Vermont will become the first state to require the labeling of foods that contain GMOs. Connecticut and Maine approved similar legislation, but those laws will go into effect only if adjoining states make the same move. Labeling ballot initiatives failed in California (2012), Washington (2013), Colorado (2014) and Oregon (2014). During the 2015 legislative session alone, state governments considered at least 100 GMO-related bills, according to National Conference of State Legislatures.

As of mid-2015, 64 countries had mandatory labeling laws for GMOs.

Still, many independent scientists and almost all major medical groups, which include American Medical Association, British Royal Society and World Health Organization (WHO), say mandatory GMO labeling isn’t necessary. Thousands of studies and safety assessments over the past 20 years failed to show any negative health or nutritional effects from eating genetically modified foods. One study that was published in 2014 included data on at least 100 billion animals and found no detrimental health effects after the introduction of genetically modified feed.

The House of Representatives approved a bill in July 2015 that would prevent states from making GMO-labeling laws and mandate that GMO labeling would remain voluntary for food manufacturers. The bill is called the “Safe and Accurate Food Labeling Act,” but labeling proponents dub it the “Denying Americans the Right To Know Act” or DARK. They say consumers have the “right to know” what’s in their beverages and foods. The Senate held a hearing to discuss potential GMO laws in October 2015, but no timeline exists for any votes.

The debate raises important questions about how GMO labeling laws might affect consumers. Would labeling create easier, more transparent access to healthful foods? Would costs increase? Consensus on these questions remains distant. For now, the issue remains mired in politics and money, while lobbying efforts on both sides spin the issue in opposite directions. The agriculture and food industries emphasize the safety of GMOs and spent $52 million in the first half of 2015 to get that message across, according to federal lobby and disclosure forms. The organic-food industry supports labeling efforts and spent $2.5 million in the first half of 2015 to get its point across, according to federal lobby and disclosure forms.

HEALTH FEARS. Genetic engineering, or modification, manipulates an organism’s DNA, usually by adding genes. Scientists have used genetic modification on plants for decades. At least 90 percent of corn, cotton, soybeans and sugar beets that are grown in the United States now are modified genetically. Because processed foods contain ingredients that are derived from genetically modified crops—including corn oil, soy lecithin and soy proteins—75 percent of supermarket products contain GMOs, according to trade group Grocery Manufacturers Association (GMA).

However, because the federal government doesn’t require labeling of genetically modified foods, consumers typically have no way to know whether their food contains GMOs. Pro-labeling groups argue that GMOs haven’t been assessed sufficiently for long-term  health effects (at least 20 years), while most medical groups and independent scientists insist that rigorous testing addressed those concerns.

If consumers want to avoid GMOs, they can seek out products that have been certified by Department of Agriculture (USDA) to be organic, which, by definition, are free of genetically modified ingredients. They also can look for the Non-GMO Project label, which companies can attach to their products by paying for third-party certification. The number of products that carry the Non-GMO label has doubled every year, Executive Director Megan Westgate tells us.

FOOD FORECAST. Labeling opponents worry that a family of four could pay an extra $500 per year for groceries. Labeling advocates’ estimates range from less than $1 to just over $15 per person per year.

FOOD FORECAST. Labeling opponents worry that a family of four could pay an extra $500 per year for groceries. Labeling advocates’ estimates range from less than $1 to just over $15 per person per year.


On the anti-labeling side, scientists and others who argue that GMOs are safe say GMO labels are misleading and stigmatizing. For instance, when shoppers see a “bird-friendly” label on, say, a brand of coffee, they often assume that all brands are harmful to birds, says Kent Messer, who is a behavioral economist at University of Delaware in Newark and the co-author of a report that was published in October 2015 on food labeling and consumer behaviors.

“Right now, we generally have yes or no labels that imply that something is good or bad,” Messer says. The likelihood that consumers will view GMO labels as warning labels is worrisome to Alison Van Eenennaam, who is a biotechnology specialist at University of California-Davis, because many GMO products address important agricultural problems, she says. Some advances include rice that’s enhanced with vitamin A, oranges that contain a spinach gene that makes them immune to a devastating insect pest and papayas that are immune to a virus that almost drove the tropical fruit to extinction. Van Eenennaam says stigmatizing GMOs could stifle scientific progress.

GMO labels might mislead in other ways, too, experts say. The GMO category doesn’t include foods that are developed through genetic techniques, such as mutagenesis, which involves zapping a plant with chemicals or radiation to see what mutations emerge. Nor does GMO apply to crops that were bred to include genes that were discovered through genetic engineering.

Loopholes in labeling laws also could leave many GMO foods unlabeled, says GMA’s Mike Gruber. Vermont’s law, for example, exempts any product that’s inspected by USDA. Gruber envisions a soup aisle where the minestrone would be labeled but the vegetable beef soup wouldn’t, even though both contained GMOs.

A better system, Messer says, would be to include two labels—one that discloses GMOs and one that explains scientific consensus on the issue.

ENVIRONMENTAL ASSAULT. In addition to health concerns and a desire for more transparency in labeling, environmental groups and organic-food companies say mandatory labeling will reduce the use of toxic herbicides. Their argument focuses on glyphosate, which is categorized as a probable human carcinogen by WHO.

Glyphosate is the world’s most widely used weed-killing herbicide and an active ingredient in Monsanto’s Roundup, which farmers spray on crops that were modified genetically to tolerate it. As GMOs have become more common, so, too, has the use of glyphosate, says Mary Ellen Kustin, who is a senior policy analyst at Environmental Working Group (EWG), which is a nonprofit research organization.

USDA data show that between 1992 and 2012, the use of glyphosate increased sixteenfold, Kustin says. As weeds become resistant to glyphosate, growers use more of it and turn to other toxic pesticides, including 2,4-D, which is an ingredient in Agent Orange. Glyphosate now is prevalent in waterways nationwide, according to EWG.

However, the connection between glyphosate and GMOs might not be so clear-cut, says weed scientist Andrew Kniss of University of Wyoming. Even though the use of glyphosate increased since 1992, he says GMO technology isn’t necessarily to blame.

Overall crop acreage increased over the same period, and that would lead to more herbicide use, Kniss says. Farmers used plenty of chemicals before Roundup came along, Kniss says, and weeds developed resistance to those, too.

Also up for debate is whether glyphosate is harmful in the first place. Industry groups and independent scientists challenge WHO’s classification of glyphosate as “probably carcinogenic” to humans, pointing to a scarcity of evidence in its report along with other major studies that demonstrate the chemical’s safety. Environmental Protection Agency and European Food Safety Authority classify glyphosate as noncarcinogenic.

Would labeling affect herbicide use? Chipotle’s experience provides a cautionary tale. To go GMO-free, the restaurant chain says it switched to sunflower oil that wasn’t modified genetically from soybean oil that was. However, sunflowers are bred to be resistant to a different class of herbicides, Kniss says, and those chemicals are responsible for the development of more herbicide-resistant superweeds than glyphosate is. Chipotle’s nongenetically modified corn, meanwhile, is likely to be treated with a variety of other herbicides, including 2,4-D.

“By buying something that doesn’t have GMOs, that says nothing about whether or not that particular product has been treated with [chemicals],” Kniss says.

After interviewing 12 experts, we believe that non-GMO labels aren’t a reliable way to ensure that a food contains fewer chemicals than does a GMO variety. GMO-free, in other words, doesn’t mean herbicide-free.

PRICE TAGS. Since California introduced a ballot proposition in 2012 to mandate the labeling of genetically modified foods, the food industry has warned that a patchwork of state laws would lead to a spike in food prices. Companies would have to create state-specific labels, Gruber says. Products that are labeled to comply with one state’s laws inevitably would end up on shelves in another state that has different laws. Companies would have to pay fines for violating those laws, he says.

If food companies decide to avoid the headache by switching to non-GMO ingredients, operating costs would increase, because many non-GMO ingredients cost more than GMO varieties do, experts tell us. That’s because it costs more to grow non-GMO crops, and the yields typically are lower. Labeling opponents worry that companies will pass the increased costs on to consumers, which could result in as much as an extra $500 per year in grocery bills for a family of four, according to a Cornell University study.

Labeling advocates’ estimates range from less than $1 to just more than $15 per person per year.

A major reason for the discrepancy in the two estimates is that no one knows whether GMO labeling would change the way that Americans shop. For example, in Europe, strong anti-GMO sentiments and mandatory labeling (on any product that contains more than 0.9 percent GMO) make it nearly impossible to find genetically modified products in stores there.

What’s clear is that labeling has the potential to change behavior, Messer says. For example, the 2010 introduction of rBST-free (hormone-free) milk labels led to a rapid shift in the dairy aisles as shoppers made it clear that they preferred the labeled versions.

“My anticipation is that if GMO labeling is mandated, that will have a major impact on the market,” Messer says. “Consumers will be highly reluctant to purchase anything that says it contains GMOs.”

Transparency is good, but GMO labels won’t give consumers necessarily the information that they believe that they’re getting.

Emily Sohn has covered health and science issues for 15 years. She has written for Discovery News, Nature, the L.A. Times and the Washington Post.

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