What is a GMO?

GMO stands for genetically modified organism. Breeders of plants and animals have long attempted to modify the genes of living things by selectively breeding the most successful organisms. This is a form of genetic modification. In most cases, however, GMO refers to changing the genes of an organism in a laboratory setting.

For thousands of years, humans have used breeding methods to modify organisms. Corn, cattle, and even dogs have been selectively bred over generations to have certain desired traits. Within the last few decades, however, modern advances in biotechnology have allowed scientists to directly modify the DNA of microorganisms, crops, and animals.

Conventional methods of modifying plants and animals—selective breeding and crossbreeding—can take a long time. Moreover, selective breeding and crossbreeding often produce mixed results, with unwanted traits appearing alongside desired characteristics. The specific targeted modification of DNA using biotechnology has allowed scientists to avoid this problem and improve the genetic makeup of an organism without unwanted characteristics tagging along.

Most animals that are GMOs are produced for use in laboratory research. These animals are used as “models” to study the function of specific genes and, typically, how the genes relate to health and disease. Some GMO animals, however, are produced for human consumption. Salmon, for example, has been genetically engineered to mature faster, and the U.S. Food and Drug Administration has stated that these fish are safe to eat.

GMOs are perhaps most visible in the produce section. The first genetically engineered plants to be produced for human consumption were introduced in the mid-1990s. Today, approximately 90 percent of the corn, soybeans, and sugar beets on the market are GMOs. Genetically engineered crops produce higher yields, have a longer shelf life, are resistant to diseases and pests, and even taste better. These benefits are a plus for both farmers and consumers. For example, higher yields and longer shelf life may lead to lower prices for consumers, and pest-resistant crops means that farmers don’t need to buy and use as many pesticides to grow quality crops. GMO crops can thus be kinder to the environment than conventionally grown crops.

Genetically modified foods do cause controversy, however. Genetic engineering typically changes an organism in a way that would not occur naturally. It is even common for scientists to insert genes into an organism from an entirely different organism. This raises the possible risk of unexpected allergic reactions to some GMO foods. Other concerns include the possibility of the genetically engineered foreign DNA spreading to non-GMO plants and animals. So far, none of the GMOs approved for consumption have caused any of these problems, and GMO food sources are subject to regulations and rigorous safety assessments.

Are GMOs safe?

In the absence of credible, independent, long-term feeding studies, the safety of GMOs is unknown. 

Are GMOs labeled?

Sixty-five countries around the world, including Australia, Japan and all of the countries in the European Union, require genetically modified foods to be labeled. Canada does not require any GMO labeling.

Under the USDA's National Bioengineered Food Disclosure Standard (NBFDS), some – but not all – products containing GMOs must be labeled in the United States. In its current form, categorical exemptions prevent this law from delivering the transparency Americans deserve.

Which foods might contain GMOs?

Most packaged and processed foods contain ingredients derived from corn, soy, canola and sugar beet — and the vast majority of those crops grown in North America are genetically modified.

The Non-GMO Project also considers livestock, apiculture, and aquaculture products at high risk because genetically engineered ingredients are common in animal feed. This impacts animal-derived products such as eggs, milk, meat, honey, and seafood.

GMOs also sneak into food in the form of processed crop derivatives and inputs derived from other forms of genetic engineering, such as synthetic biology. Some examples include hydrolyzed vegetable protein, corn syrup, molasses, sucrose, textured vegetable protein, flavorings, vitamins, yeast products, flavors, proteins, sweeteners, microbes, enzymes, oils and fats.

How do GMOs affect farmers?

Because GMOs are novel life forms, biotechnology companies have been able to obtain patents to control the use and distribution of their genetically engineered seeds. Restrictive license agreements erode farmers' right to save seed. Relying on third-party corporations to provide farmers with both GMO seed and chemical inputs such as herbicide makes those farmers beholden to Big Ag, posing a serious threat to farmer sovereignty and to the national food security of any country where they are grown.

What are the impacts of GMOs on the environment?

The most common genetically modified crops grown worldwide have been engineered for herbicide tolerance.7 In the first 20 years of the GMO experiment, the use of toxic herbicides, such as Roundup (glyphosate), increased fifteenfold.8 The use of these herbicides has led to a decline in native plants, which has downstream effects on biodiversity. Additionally, the overuse of herbicides has led to the emergence of pesticide-resistant “superweeds” and “superbugs,” which can only be killed by spraying more toxic chemicals. 

Most GMOs are a direct extension of chemical agriculture and are developed and sold by the world’s largest chemical companies. The long-term impacts of these GMOs are unknown. Once released into the environment, these novel organisms cannot be recalled.

In the future, GMOs are likely to continue playing an important role in biomedical research. GMO foods may provide better nutrition and perhaps even be engineered to contain medicinal compounds to enhance human health. If GMOs can be shown to be both safe and healthful, consumer resistance to these products will most likely diminish.