Genetically Engineered Foods: Facts and Fears

Genetically engineered foods may already be on your menus. Are they safe? Healthy? We answer your questions...

In the not-too-distant future, your dinner plate may be filled with science experiments – salmon, meat and other foods that have been “engineered” by a technology firm. Sound yummy?

Salmon is the latest and most controversial food to come out of a test tube. The Food and Drug Administration’s (FDA) Veterinary Medicine Advisory Committee recently held hearings about AquAdvantage® Salmon, genetically engineered by the biotechnology company AquaBounty.

Consumer groups, including the Consumers Union, claim that more rigorous testing needs to be done to ensure that AquaBounty’s “super salmon” is safe for our health and the environment. The FDA agrees there’s not enough research available to determine safety.

So it’s unlikely you’ll see that particular product at the fish counter anytime soon. But unless you’re watchful, you’re probably eating other genetically engineered (GE) foods – in cake mixes, canned goods, cereals and more.

Should GE foods be on your plate? Are they potential health hazards? We asked scientists and nutrition experts to explain the issues behind this still-developing science.

What Is Genetic Engineering?
The process involves inserting foreign genes into the DNA of a plant, animal, bacteria or other organism. Genetic engineering can alter crops or animals, turning them into what’s known as a genetically modified organism (GMO), which is what you might see on food labels.

GEs are also used to develop drugs and vaccines.

"Most of the insulin prescribed [for diabetes] in America is genetically engineered,” notes Tina Ruggiero, a New York-based dietitian and co-author of the forthcoming book The Best Homemade Baby Food on the Planet (Fair Winds Press). And, last year, the FDA approved an anti-clotting drug made from proteins extracted from the milk of genetically engineered goats.

GE food manufacturers claim they’ll save the world, promising higher yields to feed a hungry planet because crops can be engineered to resist disease, insects and herbicides. For example, Monsanto’s GE corn can withstand the herbicide Roundup.

Animals can also be genetically modified to resist disease, as well as to grow faster. AquaBounty’s salmon includes growth hormones of Chinook salmon (the largest in the species) and antifreeze genes from an ocean pout, an eel-like fish.

By inserting these genes into the DNA of an Atlantic salmon, the fish grows faster, year-round, and reaches market weight in half the time of natural salmon. The fish are also engineered to be all female and sterile, so if they escaped from tanks, they would, theoretically, be unable to contaminate the wild fish population.

How is that different from crossbreeding, which farmers have always done with plants and livestock? Traditional crossbreeding creates new varieties through natural sexual reproduction. Horticulturists can crossbreed tomato varieties to create a hybrid, for example. But they can’t cross a tomato with a rose.

But genetic engineering can – by allowing developers to “move genes across species boundaries to produce novel organisms ... that do not occur in nature and, indeed, cannot be developed by natural means,” according to the Union of Concerned Scientists’ (UCS) policy statement.

“Legally, the FDA views genetic engineering as an extension of conventional breeding,” says Michael Hansen, Ph.D., senior scientist at the Consumers Union. Therefore, the agency doesn’t require the safety assessments it does for GE plant foods; non-GE foods have no assessments.

But Hansen and other consumer advocates contend that GMOs are different from natural varieties and therefore require rigorous safety standards. For example, in nature you couldn’t cross a tomato with spinach, which is a cold-season crop, to grow tomatoes year-round. But genetic engineering makes this a possibility.

Are GE Foods Safe to Eat?
The FDA says GE plants are safe because they’re not “materially” different from conventional plants.

“The FDA doesn’t require any safety studies whatsoever,” says Jeffrey Smith, of the anti-GMO consumer advocacy group Institute for Responsible Technology. “The policy was developed based on the assumption – since 1992 – that the agency is not aware of any information that GMOs are significantly different.”

But, unlike plants, the FDA classifies GE animals like a new drug – considered unsafe until proven otherwise. Last month’s hearings asked the advisory committee to evaluate AquaBounty’s AquAdvantage® Salmon on health and environmental safety, based on the company’s own research.

Hansen and other consumer advocates questioned that research.

“Many of the studies supporting this technology have sample sizes of [only] 5-7 fish,” says Chuck Benbrook, Ph.D., chief scientist at The Organic Center.

And none of AquaBounty’s studies reflected the actual conditions under which the fish would be commercially raised, Benbrook says.

Many experts are concerned that current genetic engineering is still in its infancy. Scientists can’t yet control where genes are inserted in DNA, and that can affect outcome, Hansen says.

Do GE Foods Have Health Risks?
Although the FDA deems GE foods safe, research has linked them with a large number of health issues, according to the American Academy of Environmental Medicine (AAEM), Union of Concerned Scientists and other groups. Among them: infertility, impaired immune function, accelerated aging, and disrupted insulin and cholesterol regulation. Other studies tie them to liver, kidney and gastrointestinal problems.

Mice fed GE corn are prone to infertility and birth defects, according to a 2008 study by Austria’s Federal Ministry of Health, Family and Youth. Another 2008 study, published in the Journal of Agricultural and Food Chemistry, revealed that mice fed a diet of GE corn were more likely to have impaired immune response than those who nibbled regular corn.

“Unfortunately, there’s no epidemiological data [on GE food fed to humans],” says Amy Dean, D.O., a member of the AAEM’s board of directors. “But what we’ve seen over the years is that patients are getting much sicker, and since GM foods have come on the market, chronic diseases are skyrocketing.”

Last year, AAEM members decided that the evidence against genetically modified foods was strong enough to issue a position paper, co-written by Dean, urging physicians to advise patients to avoid them.

Hansen points to one study of GE corn that compared the enhanced version with its natural variety, both grown under identical conditions. It demonstrated that “the process of genetic engineering took a gene for a known allergen that was normally turned off and turned it on,” he says. That means engineered corn could provoke an allergic reaction that its natural variety wouldn’t.

The World Health Organization (WHO) also urges testing for allergens in GE fare. The global health agency is also worried about the potential – though low – for genetic transfer of the allergen gene from engineered foods to people.

Other Concerns About GE Foods
Benbrook, Hansen and the UCS question the unintended environmental consequences of engineered foods. For example, take the case of GE salmon cultivated in inland tanks in the tropical highlands of Panama, not their native chilly Atlantic waters.

“It’s inevitable that raising these fish in Panama will degrade the nutritional quality of the salmon and create problems requiring antibiotic use,” Benbrook warns. That, in turn, could create antibiotic-resistant bacteria.

And if crops are engineered to be herbicide- and insecticide-resistant, there’s a chance that more insecticide-resistant pests and herbicide-resistant weeds will develop to adapt to them.

Environmentalists also cite diminished biodiversity, as GE super-crops could overtake natural varieties.

Besides, promises of increased yields don’t appear to be panning out. Last year, the UCS released a report analyzing two decades of research on GE crops in the United States and found that GE yields haven’t significantly increased over non-GE crops.

Are There Any Health Benefits?
Despite concerns about the current state of GE technology, many agree that bioengineering has tremendous potential for enhancing our health.

“The day will come when there will be foods bred to enhance nutrition and remove allergens,” Benbrook says.

We can create a greener movement with biotech and engineering if we do it responsibly, says Ruggiero, who owns a 360-acre farm in Alabama. “If it’s done with the public’s interest and benefit in mind, it can be very beneficial to human nutrition.”

For example, British researchers are working on a purple-hued tomato engineered with snapdragon genes to enhance its levels of the health-boosting antioxidant anthocyanin.

Which Foods Contain Genetically Modified Organisms?
Eight GE crops are used in our food supply: corn, soy, canola, cotton, sugar beets, papaya, zucchini and crookneck squash. The main crops, soybeans and corn, are in hundreds of foods, from vegetable oils and high-fructose corn syrup to supplements and food additives.

And many GE crops are used in livestock feed. In addition, this summer the Supreme Court lifted a ban on herbicide-resistant GE alfalfa, which could also be used in livestock feed.

Dairy producers may inject cows with an engineered synthetic form of bovine growth hormone called rbST or rbGH, which boosts milk production by up to 15%. This hormone can cause problems in cows, such as lameness, and the European Union and Canada have banned it for animal welfare.

Although rbST has been found safe for humans, consumer opposition has led many American retailers – including Kroger, Publix and Trader Joe’s – to ban dairy products with rbST.

There aren’t any genetically engineered animals in our food supply – yet. If approved, the GE salmon would be the first on the market.

How Do I Know If My Food Has Been Genetically Engineered?
“Most processed foods have some GM components in them,” Dean says. According to the nonprofit Non-GMO Project, about 80% of packaged foods contain GMOs.

And because most livestock feed is derived from GE crops, you’re indirectly ingesting GE foods when eating conventionally produced beef, pork or poultry.

A Center for Science in the Public Interest poll found that up to 70% of consumers want genetically engineered food to be labeled as such. But because the FDA decreed, in 1992, that GE foods are not “materially” different from other foods, therefore do not have to be labeled – they’re now abundant in our food supply.

Here’s how to avoid eating engineered foods:

Choose fresh, whole foods. For the most part, ears of corn and other produce will be GE-free, Benbrook says. Some fresh produce does come engineered, including papaya, zucchini and other squash, but they’re available only on a limited basis.

Avoid processed foods. Those typically include additives made from GE corn, soy, cotton and dairy.

Go organic. By definition, USDA-certified organic foods can’t contain GE components. That includes organic beef, dairy, poultry and pork products, which can’t be raised on GE feed.

Read labels carefully. The Non-GMO Project Verified seal appears on products that have been tested and vetted by a third party. Some foods carry variations of a “no GMOs” label, but that’s a voluntary – and unregulated -- designation.

What’s Your Food Safety IQ?
There's nothing worse than polishing off a delicious meal, only to be struck later with nausea, vomiting and diarrhea. Little did you know when you were enjoying your entrée that you'd be paying a heavy price within hours. Food poisoning, whether contracted in a restaurant or in your own home, is never fun. But are you unnecessarily putting yourself at risk?