All About Genetically Modified Foods

Farmers, ranchers, and vintners have been modifying and improving crops, livestock, and wine for thousands of years. This has been performed through cross-fertilization and selective breeding.

Recent advances in genetics, however, have made this process smoother and faster. Today's agricultural and food industries use genetic engineering to develop new and better foods and food-related products.

Modifying foods by deleting or inserting certain genes into a plant is similar to cross-fertilization, a process that has produced varieties of apples, hybrid corn, and the tangelo, a hybrid of the tangerine and the grapefruit.

When cross-fertilization and other traditional modification methods are used, thousands of genes from several plants are mixed to produce offspring. It may take many years and attempts to produce the desired traits. Today, scientists use genetic engineering to make a desired product. This allows them to move only the desired genes, which makes the process quicker as well as more precise and predictable. By controlling the insertion of one or two genes into a plant, scientists can give it a specific desired characteristic.

The first genetically modified (GM) food product for human consumption was a tomato, which went on the market in 1994. It had a longer "shelf life" than other tomatoes. Since then, potatoes, squash, corn, potatoes, and sugar beets have joined the ranks of GM foods. According to the Grocery Manufacturers of America, up to 75 percent of all processed foods sold in grocery stores may have GM ingredients.

Benefits and risks

The FDA, USDA, and EPA all oversee GM food production. The FDA determines that foods made with GM plants are safe to eat, the USDA makes sure the GM plants are safe to grow, and the EPA regulates the pesticides used on GM plants.

GM foods are generally regarded as safe. However, the safety of each new GM food should be judged individually.

There are many advantages to GM foods. One advantage is that by selectively breeding for desired traits, farmers and scientists have produced plants and animals that are more resistant to disease, drought, and pests. This enables fewer pesticides and less water to be used during the growing process. Other advantages are improved taste and nutritional value, increased production of food, and a quicker growing period.  

GM foods could benefit areas of the world where malnutrition is a problem. They can be bioengineered to contain certain nutrients. "Golden rice," for instance, has been developed to contain beta-carotene, a precursor of vitamin A. Vitamin A deficiency can cause blindness and a weakened immune system. It is also common in certain developing countries that depend on rice.

Although no reports of illness or injury from GM foods have been reported, there may be risks that have not yet been observed. Environmental concerns include the possibility of plant and animal extinction from modified plants or animals crossbreeding with their unmodified cousins. Another concern is if plants developed to be resistant to certain pests could become vulnerable to other pests. Other concerns include the introduction of "super weeds" if a plant transfers a gene to a weed or if GM plants could cause unexpected allergic reaction. 

Further concerns hinge on social and political issues, such as if countries that develop GM crops make them available to underdeveloped countries or if they will ensure the safety of their products. 

Future of genetically modified foods

The first GM plants were developed to make it easier for farmers to grow crops for animal feed or to be processed into oils. These "first generation" crops were able to resist certain pests and diseases or tolerate herbicides that got rid of weeds. Ongoing research is being done to develop GM crops that are more tolerant to cold, heat, drought, or salt.

A "second generation" of GM crops is aimed directly at consumers. These include fruits and vegetables--like that first tomato--that have a longer shelf life, improved taste, and added nutrients. Ongoing research is being done to develop GM foods, such as citrus fruits that are less bitter.

A "third generation" of GM crops is exploring ways to use plants to create edible vaccines and antibiotics, as well as substances such as anticoagulants, blood substitutes, and hormones. Additional ideas include plants that can absorb and trap toxic substances and trees that withstand disease.

Labeling of genetically modified foods

You may not be able to tell when you're buying GM foods because the FDA generally doesn't require manufacturers and producers to label them as such. The reason for this is that GM foods are considered no different in quality or safety from conventionally produced foods. A GM label would be required only if the GM food were obviously or significantly different. For instance, if the food contained different nutrients or possible allergens.