By Lisa Rapaport

(Reuters Health) – Roughly half of children and adults who say they’re allergic to sesame don’t have a history of convincing symptoms, a U.S. study suggests.

Researchers examined data on 78,851 children and adults and found that 102 kids and 149 adults had a convincing sesame allergy based on experiencing at least one clear immune reaction in the past.

Overall 0.53% of children in the study had a reported sesame allergy, but only 0.21% had a history of convincing symptoms. And while 0.44% of adults had a reported a sesame allergy, only 0.24% had convincing symptoms.

Only about one-third of children and adults with convincing sesame allergy symptoms reported use of epinephrine to treat a severe allergy attack, researchers report in JAMA Network Open.

“Sesame allergy can be just as dangerous as any other common food allergy as it may result in anaphylaxis, a potentially life-threatening allergic reaction,” said Dr. Ruchi Gupta, senior author of the study and director of the Center for Food Allergies and Asthma Research (CFAAR) at Northwestern Medicine and Lurie Children’s Hospital in Chicago.

Sesame is believed to be the ninth most common food allergy in the U.S., and mandatory labeling on packaged foods is only required for the top eight causes of allergies: milk, egg, fish, shellfish, tree nuts, peanuts, wheat and soybeans, Gupta said by email.

“The FDA is currently considering including sesame on this list,” Gupta said. “Sesame, specifically, is often a hidden ingredient is spices and sauces and sesame oil and seeds, and is commonly found in Asian cuisine.”

Just 55.5% of the kids and 37.7% of the adults with convincing sesame allergy symptoms had a doctor diagnose them with sesame allergies, the study found.

At the same time, about 41% of people who did have a physician-diagnosed sesame allergy didn’t actually have convincing symptoms.

About 37% of people with a convincing sesame allergy reported having had at least one severe reaction to sesame.

More than four in five people with sesame allergies had at least one other food allergy as well. Almost half of the time, this was a peanut allergy.

One limitation of the study is that researchers lacked data from allergy tests to confirm whether people really had a sesame allergy or to verify the severity of any allergies.

Allergic reactions to sesame can be similar to allergic reactions to other foods, said Jennifer Protudjer, author of an accompanying editorial and a researcher at the University of Manitoba in Canada.

Symptoms can include hives, itching or redness on the skin, swelling of the lips, nausea, vomiting, diarrhea, low heart rate or low blood pressure, coughing or difficulty breathing, Protudjer said by email.

“Anyone who has these symptoms within a few minutes of eating sesame should be treated with intramuscular epinephrine,” Protudjer said. “Even if the symptoms resolve quickly, they would be advised to go immediately to the nearest emergency room, or medical center, as symptoms can reappear.”

SOURCE: https://bit.ly/30Ei6fe and https://bit.ly/2LcbiyS JAMA Network Open, online August 2, 2019.