by Barbara Ruhs, M.S., R.D.
If you were fed infant formula as a baby, or have eaten fast food, breakfast cereal, margarine, frozen yogurt or artificial sweetener, chances are that you've consumed genetically modified organisms (GMOs.) GMOs are ubiquitous in the food supply -- present in 75 to 80 percent of processed foods in the U.S., according to the
Most recently, GMOs received national attention after the defeat of
Here are some answers to common questions about GMOs.
What are GMOs?
A GMO is an organism that has been genetically altered using a laboratory process, also referred to as biotechnology or genetic engineering (GE), in which genes from the DNA of one species are extracted and artificially placed into the genes of another organism to produce a desired trait in the plant. Genes may come from other plants, bacteria, viruses, insects, animals or even humans.
Which foods contain GMOs?
First introduced in the mid-1990s, the primary sources of GMO foods are in industrial crops, including soybeans, corn/maize, rapeseed (canola oil), cotton, and sugar beets. Predominantly, these crops are transformed into food ingredients used in processed foods (see "Common GMO Ingredients in Foods"). Additionally, due to the low cost of production, many of these crops are also used as animal feed for agricultural animals in feed lots raised for meat. The produce department is the only other location in the supermarket where you may find GMOs today -- for example, in Hawaiian-grown papaya and some varieties of zucchini and summer squash.
What are the benefits of GMOs?
Traditional cross-breeding to create desirable traits in a plant, a form of agricultural technology that has been used by farmers for centuries, is considered "natural." In fact, many of the plant foods that you find in the produce department of your local grocery store are a product of traditional plant breeding. Just consider the multitude of apples on the market today, each variety having its own desired characteristics for a multitude of use and taste preferences. However, scientists using traditional cross-breeding, could take years to create such desired characteristics in plants.
Modern agricultural advances have led scientists to develop more time-efficient techniques, including genetic engineering, which can offer greater precision in isolating specific genes for important traits that have the potential to offer benefits. Historically, agricultural biotechnology has been driven by the demand to improve agricultural efficiency, including increasing production yields by protecting plants from natural pests, reducing water and maximizing land usage.
More recently, attention has focused on improving nutritional quality, food production functionality (appearance and durability), and environmental sustainability. Some plants have been genetically modified to help them survive -- in the mid-1990s, genetic engineering saved the Hawaiian papaya from extinction. The papaya ring-spot virus had previously wiped out crops in the '60s and '70s and when traditional plant-breeding failed, researchers turned to genetic engineering and successfully saved the papaya.
What are the risks to the environment?
Many experts raise concerns about the potential effects of GMOs on the environment. Plants have been genetically engineered to have built-in herbicide resistance, so that herbicides can be applied to the GMO crops without harming them. Eventually, new, stronger weeds will evolve requiring even higher doses of herbicide application to combat them. According to a study published in Environmental Sciences Europe by
GE crops may also lead to other negative environmental effects, ultimately damaging the natural balance of nature's ecosystems. Insecticide-resistant crops may also increase the use of chemical pesticides that ultimately may wipe out beneficial insects, such as bees, that play an important role in pollination. Furthermore, there is concern regarding the reduction in crop diversity as a result of the mass cultivation of single GE plant varieties, which could threaten the long-term viability of our global food supply.
Are GMOs safe?
A large question mark remains on the long-term consequences of GMO intake on human health -- much skepticism remains concerning their relationship to cancer risk, allergies, and digestive disorders. Recently, a highly publicized research paper, published in the
How are GMOs labeled?
Outside of the U.S., much of the world, including