Scott H. Sicherer, M.D., responds:
Genetically modified (“GM”) foods are those produced from GM organisms (“GMOs”), which are typically crops, including fruits, vegetables and grains. Prior to modern biologic techniques, farmers might have selected and bred better tasting or more hearty strains of their crops, a form of genetic engineering.
In the past decades, it has become possible to insert genes that can, for example, make a plant resistant to specific diseases or insects, make a plant easier to grow with less chemical weed killers, or improve how it ripens.
Arguments for pursuing GM foods include the need to keep up with worldwide food production needs; to reduce costs, pollution, and use of chemicals to manage crops; and to develop foods with better nutrients. About 85 to 90 percent of corn and soy produced in the United States is GM.
The general safety of GM foods is a topic of strong interest in the international
public health community. There is broad scientific consensus that GM foods on
the market pose no greater risk than their normal counterparts, although there are skeptics and critics. Nonetheless, there are no documented ill effects. Regulatory and scientific agencies have developed international guidelines to address safety, with attention to nutrition, toxicity and a variety of concerns in addition to allergy.
With regard to allergy, the potential concerns include: transfer of a known
allergen, creation of a new allergen, or having a plant produce more of a protein
that is or may be an allergen. The Codex Alimentarius Commission of the World
Health Organization has recommended a “weight-of-evidence” approach to evaluate GM foods for allergy risks, meaning that multiple forms of safety assessment are undertaken and considered. These include studies to address: Has the protein introduced caused allergy or illness when previously eaten? Does the protein resemble the many well-characterized allergenic proteins? Does it behave like typical allergens, for example with resistance to digestion? Does it alter the amount of proteins, including any allergens, the plant was making?
Although there is currently no evidence that GM foods are more allergenic or have somehow contributed to the apparent increase in food allergies, there are no comprehensive studies on this topic. Most experts do not include GM foods high on their “working list” of reasons for the increase in food allergy because there is little scientific reason to suspect a connection, and many other theories are more compelling. However, attention to the risk of allergy is an ongoing concern.
Additional crops and also GM animals are under study. Experiments are
also underway to use genetic engineering to develop less allergenic forms of common food allergens. It remains a key focus to ensure the safety of these foods from an allergic point of view in the future, but the products currently on the market have been widely studied and appear to be safe.
This article was originally published in the Summer 2013 issue of FARE’s Food Allergy News. Read more of the newsletter here.