Sesame allergies seem to be a lot more common that previously thought. According to a new study out this weekend, as many as 1.5 million Americans could be allergic to sesame, and the findings may prompt the Food and Drug Administration to require new warning labels that identify sesame in foods.
Researchers at Northwestern University in Chicago looked at nationally representative survey data involving more than 50,000 households across the country. The survey specifically asked respondents to report the foods, if any, they were allergic to, as well as if their allergy had ever been confirmed by a doctor. They were also told to report the symptoms they experienced during their most severe reaction, choosing from a list of symptoms.
Based on the responses, the team found that 0.49 percent of people reported having a food allergy to sesame. At least 0.23 percent were found to have a convincing allergy to sesame—defined as experiencing at least one very common symptom of food allergy, such as hives or a swollen throat. And another 0.11 percent reported being diagnosed with a sesame allergy by their doctors, but didn’t report one of these symptoms.
These might seem like small numbers, but even if you only combined the percentage of people who had a convincing or diagnosed sesame allergy (0.34 percent), that’d still amount to about 1.1 million children and adults in the U.S. That’s a higher toll than found in previous research, which suggested that 0.1 to 0.2 percent of Americans had a sesame allergy. And if the admittedly strict criteria used by the team is leading to an underestimation of the problem, then the number would be even higher.
“Overall, a total of 0.49 percent of the US population, or more than 1.5 million children and adults, may have a current sesame allergy, indicating a greater perceived burden of sesame allergy than previously acknowledged,” the authors, whose study was published Friday in JAMA Network Open, wrote.
The results are especially relevant in light of the FDA’s recent decision to consider mandating warning labels for sesame, similar to labels that warn about the presence of eight major food allergens, like dairy, eggs, and tree nuts. Last October, in order to guide that decision, the agency put out an open request for scientists to provide them information on the prevalence of sesame allergy in the U.S. It was that call that prompted the researchers to publish this study, based on earlier work they had done with the same data.
According to the study, there might actually be more people in the U.S. with a possible sesame allergy than there are people allergic to certain tree nuts like pine and macadamia nuts. Sesame labels are also already mandated in some other countries, including Australia, Canada, Europe, and New Zealand. Last July, Illinois became the first U.S. state to do the same.
“It’s going to be challenging,” lead author Rachi Gupta told NPR, referring to the implementation of the recent Illinois law. “But hopefully it’s the first step for it to become a national law.”
Without a national law, many products will continue to not warn people about sesame—with potentially disastrous consequences. In the current study, a third of people with convincing sesame allergies reported needing emergency room care at least once because of their reactions. People in general were also less likely to be diagnosed with sesame allergy than others with more widely known allergies.