To Your Health

Q. I don't know whether to be worried about genetically modified food or not. Should I be, and if so why?

A. Genetic modification was going on for years before this current controversy broke out. It is known as hybridization and has been considered beneficial because it results in what is called "hybrid vigor." For instance, Americans have been eating modified (hybrid or crossbred) corn for decades, but hybridization only works for species that can interbreed. Today's genetically modified foods are different in that they can be produced by the insertion of genes from an entirely different species.

Although a lot is published about GM foods, it is mainly in the form of commentaries and letters to the editor. Solid research published in reputable journals on the safety of GM foods is surprisingly scant. GM foods might be as safe as conventional foods but public distrust runs high. It is important that debate be based on scientific evidence and not driven by the financial interests of multinational companies on the one hand or ill-informed public fears on the other.

The benefits cited for GM foods include increased nutritional value and natural pest/disease-resistance, which would reduce the use of pesticides. Possible detrimental outcomes include producing foods with novel toxins or allergens and development of antibiotic-resistant microorganisms or herbicide-resistant weeds. As an example of the benefits, a strain of rice with higher vitamin A content has already been developed, which promises to reduce the incidence of blindness in developing countries. On the other side, an internal insecticide in GM corn might threaten the life of monarch butterflies.

A push for labeling of GM foods has widespread support from consumers but is of course opposed by the biotech industry. And, although two-thirds or more of Americans desire labeling of GM foods, half said they would pay $10 or less per year for labeling. Such information might be of little practical worth to the majority of the population, but someone with a life-threatening allergy to peanuts would need to know if a GM food contained genetic material derived from peanuts.

Tommy Thompson, U.S. Secretary of Health and Human Services, recently told the 15,000 attendees of BIO 2002 that the Bush administration opposes mandatory labeling of genetically modified foods. It is thought that such labeling would tend to frighten consumers by implying that GM foods are somehow inferior to conventional foods. At present there is no evidence that the presence of foreign DNA in a food is in any way detrimental to a human consuming that food, though there is concern that the protein coded by the DNA might be allergenic to some individuals. Most believe it is the responsibility of companies developing genetically modified foods, and of regulatory authorities that approve their marketing, to ensure that they are at least as safe as the traditional foods they are intended to replace.

We are in the unenviable position of having to make decisions with less information than we need. Until the dust settles, it is prudent for children, pregnant women, and people with known food allergy to avoid GM foods. GM foods are probably safe for most of us to eat, but effects on the environment are difficult to predict at present.