Sesame allergy is more common than you thought

Northwestern Medicine researchers have discovered that sesame allergy affects more than 1 million children and adults in the US — more than previously estimated — yet sesame labelling is currently not required by US law, as opposed to other allergens like peanut and milk.

Study investigators administered an internet and telephone survey to more than 50,000 US households. The survey asked detailed information about any suspected food allergies, including specific allergic reaction symptoms, details about clinical diagnosis of food allergies and demographic information. They obtained responses for a nationally representative sample of approximately 80,000 children and adults, with the results published in JAMA Network Open.

Results indicate that more than 1.5 million children and adults in the US (0.49% of the population) report a current sesame allergy, and more than 1.1 million (0.34% of the population) report either a physician-diagnosed sesame allergy or a history of sesame-allergic reaction symptoms. The data also indicated that many individuals who report sesame allergies and experience potentially severe allergic reactions are not obtaining clinical diagnosis of their allergies.

“Clinical confirmation of suspected food allergies is essential to reduce the risk of unnecessary allergen avoidance as well as ensure patients receive essential counselling and prescription of emergency epinephrine,” said first author Christopher Warren, an investigator with Stanford’s Sean N. Parker Center for Food Allergy and Asthma Research.

Unlike allergies such as milk or egg, which often develop early in life and are outgrown by adolescence, sesame allergy affects children and adults to a similar degree. In addition, four in five patients with sesame allergy have at least one other food allergy: more than half have a peanut allergy, a third are tree-nut allergic, a quarter are egg-allergic and one in five are allergic to cow’s milk.

“Our study shows sesame allergy is prevalent in the US in both adults and children and can cause severe allergic reactions,” said lead study author Dr Ruchi Gupta, a professor of pediatrics and medicine at the Northwestern University Feinberg School of Medicine.

The study provides the first up-to-date estimates on the current prevalence of sesame allergy among US children and adults in all 50 states. It also directly informs ongoing regulatory rule-making by the US Food and Drug Administration (FDA), which is currently considering whether sesame should be added to the list of key food allergens for which mandatory product labelling is required.

Unlike in other countries, such as Australia, current US law does not require sesame-containing products be labelled, only mandating labelling of the top eight allergenic foods/food groups — peanut, milk, shellfish, tree nuts, egg, wheat, soy and finfish — along with proteins derived from them. Furthermore, sesame products are often labelled in a potentially confusing manner, such as tahini, which increases the risk of accidental ingestion.

“It is important to advocate for labelling sesame in packaged food,” Dr Gupta said. “Sesame is in a lot of foods as hidden ingredients. It is very hard to avoid.”

Image credit: ©stock.adobe.com/au/Natasha Breen