Spike in sesame allergies in children flagged by US medical research agency

05 Nov 2019 --- Research from the National Institutes of Health (NIH), a US medical research agency, has revealed that sesame allergy is becoming increasingly common among children. The NIH scientists also found that sesame antibody testing — an all-round controversial topic — accurately predicts whether a child with a food allergy is allergic to sesame. As concerns rise, the US Food and Drug Administration (FDA) has issued a request for epidemiological data to find out whether regulatory action requiring sesame to be labeled as an allergen on packaged foods will be necessary in the future.

“It has been a challenge for clinicians and parents to determine if a child is truly allergic to sesame,” says Anthony S. Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID), part of NIH. “Given how frequently sesame allergy occurs among children who are allergic to other foods, it is important to execute caution to the extent possible when exposing these children to sesame.” 

Published in the journal Pediatric Allergy and Immunology, this study found that only an estimated 20 to 30 percent of children with sesame allergy outgrow it.

Research parameters
Standard allergy tests, such as the skin-prick test and the allergen-specific antibody test, continue to yield inconsistent results in predicting sesame allergic reactions, the researchers highlight. Many studies evaluating the utility of these tests for sesame allergy have included only children suspected to have sesame allergy. 

Dr. Pamela Frischmeyer-Guerrerio, Deputy Chief of the NIAID Laboratory of Allergic Diseases and Chief of its Food Allergy Research Unit, led her research team to take a different approach and evaluated the sesame antibody test in a group of over a hundred children with food allergies whose sesame-allergic status was unknown.

The participants in the study ingested gradually increasing amounts of sesame under medical supervision to test whether they would react to the sesame or not. The scientists found that 15 of the 119 children were sesame-allergic, 73 were sesame-tolerant, and sesame-allergic status could not be determined for 31 children, mainly because they declined the oral food challenge. Among the 88 children whose sesame-allergic status was definitive, 17 percent had sesame allergy.

The scientists measured the amount of an antibody called sesame-specific immunoglobulin E (sIgE) in the blood of these 88 children. With this information, the researchers developed a mathematical model for predicting the probability that a child with food allergy is allergic to sesame. According to the model, children with more than 29.4 kilo international units of sIgE per liter of serum have a greater than 50 percent chance of being allergic to sesame. The researchers affirm that their model should be validated by other studies to ensure its efficacy, before it can be used in clinical practice. 

A growing concern
Sesame is among the 10 most common childhood food allergies. Severe reactions to sesame are common among sesame-allergic children. About 1.1 million people in the US have sesame allergy, according to a recently published study funded by NIAID. Right now, sesame is not recognized as a major allergen and therefore not required to be declared as an allergen on food labels. However, as more and more adults are indicating sesame intolerance, the FDA is compelled to reevaluate sesame’s status. 

The agency is therefore advancing a new effort for the consideration of labeling for sesame to help protect people who have sesame allergies. Its first step is to gather the necessary information on sesame and sesame allergies from epidemiologists, nutritionists, allergy researchers and physicians to find out to what extent sesame-related labeling regulations will have to be updated in the future. 

Open sesame to the public
Nuts and seeds have long been touted as healthy dietary additions for their protein, vitamin E and healthy fat content. A report released by Knorr and The World Wide Fund for Nature (WWF) highlighted their importance. The report notes that sesame seeds, alongside walnuts and flax seeds are strong ingredients in this category.

Meanwhile, a vast amount of research has gone toward studying children’s allergies. This is partly due to growing evidence that food allergies are rising globally, particularly among young children. Food companies are becoming increasingly aware of allergens in their products and consumers’ approach toward it. Responding to the steady increase in demand for non-allergen ingredients, EHL Ingredients overhauled production processes to completely segregate lines for ingredients containing allergens and non-allergen products. 

Edited by Anni Schleicher