GMOs cause new food allergies
Every approved GMO crop undergoes rigorous allergenicity testing before entering the food supply. No novel allergies attributable to approved GMO foods have been documented. The rise in food allergy prevalence preceded GMO commercialization and occurs in countries with minimal GMO exposure.
What we know
Genetic modification of food crops involves inserting specific genes to produce desired traits such as pest resistance, drought tolerance, or an enhanced nutritional profile. A reasonable concern raised early in the development of the technology was that this process might inadvertently introduce new allergenic proteins into the food supply. To address this concern directly, international regulatory bodies including the FDA, USDA, EPA, WHO, and the European Food Safety Authority require comprehensive allergenicity assessments for every new GMO crop before it can be commercialized anywhere in the world.
These assessments examine several specific questions: whether the source organism of the inserted gene is already known to cause allergies in some people, whether the new protein shares structural or sequence similarities with known allergens using bioinformatic comparison databases, whether the protein is resistant to digestion by simulated gastric fluid (a property that would allow it to survive long enough in the gut to trigger an allergic response), and whether the protein binds IgE antibodies drawn from the serum of patients with known allergies. This screening process has a proven track record: in the one well-documented case where an allergenic protein was accidentally introduced, a Brazil nut storage protein transferred into experimental soybeans in the mid-1990s, the screening process detected the risk and the product was voluntarily withdrawn by its developer before it ever reached consumers or the commercial market.
A 2020 review published in the Journal of Food Allergy, drawing on decades of post-marketing surveillance data across multiple countries, found no evidence that any approved GMO food has caused allergic reactions in the general population once on the market. The National Academies of Sciences' comprehensive 2016 review of GMO safety reached the same conclusion after examining the broader evidence base. Critically, the rise in food allergy prevalence observed in Western countries began well before GMO crops were first commercially introduced in 1994, and a comparable rise in allergy prevalence has also occurred in countries such as the United Kingdom where GMO crop cultivation and consumption have remained minimal, undermining any simple causal story linking the two trends.
FDA guidance issued in 2023 reinforced that GMO foods are held to the same strict safety standards as all other foods sold in the United States, and explicitly states that approved GMOs are not more likely to cause allergic reactions than their conventional counterparts. Allergists and immunologists who study the broader rise in food allergies point instead to factors such as changes in early childhood dietary exposure patterns, the hygiene hypothesis, and shifts in gut microbiome composition, none of which are specific to genetically modified crops. Some GMO crops are in fact engineered specifically to reduce allergenicity rather than introduce it, such as experimental low-allergen soybean and peanut varieties developed using gene-silencing techniques to suppress the expression of naturally occurring allergenic proteins, an application of the same technology aimed at the opposite outcome from what the myth describes. Consumer confusion on this topic is compounded by the fact that food allergy prevalence genuinely has risen substantially since the 1990s in many high-income countries, a real and concerning public health trend that researchers attribute to multiple factors unrelated to crop genetics, making it easy for the two unconnected trends to be mistakenly linked in public discussion.
Common claims
- GMOs introduce new proteins that trigger food allergies.False for approved GMOs. All undergo allergenicity testing before market approval.
- The rise in food allergies is caused by GMOs.False. The allergy rise predates GMO commercialization and occurs in low-GMO countries.
- No GMO crop has ever been pulled for allergy concerns.False. Brazil nut-soy was voluntarily withdrawn before market, showing screening works.