Edible seeds becoming major food allergens
The inclusion of seeds in food and food products may be a contributing factor in the increase of seed allergies.
Hypersensitivity to seeds such as sesame, sunflower, poppy, pumpkin, flax, and mustard has evolved as a large source of food allergies, with sesame being the most prevalent, according to a study in Allergy.
Researchers from Louisiana State University Health searched for articles on hypersensitivity reactions to commonly consumed seeds published from January 1930 to March 2016.
Compared with other seeds, allergy to sesame was reported more frequently, with an estimated prevalence of 0.1% to 0.2%. In countries such as Israel and Saudi Arabia, sesame is in the top 5 of most common foods to trigger food-induced anaphylaxis. In the European Union, sesame is on the mandatory list of allergen labeling. However, sesame is not yet part of mandatory labeling in the United States.
The increased inclusion of sesame seeds, as well as sesame seed oils, in children's diets may be contributing to the increase in seed hypersensitivity. Cases of allergic contact dermatitis have been reported from exposure to seed oils; however, the most common symptoms include oral allergy symptoms and anaphylaxis. Other seeds, such as sunflower, poppy, pumpkin, flax, and mustard, while not as common, were also reported as seed allergens. Symptoms mostly included anaphylaxis.
Diagnosing seed allergies should be conducted through skin testing (SPT) as well as serum IgE levels and an oral challenge test. Hypersensitivity to seeds may not show up in one test but can appear in another. For example, tahini, or sesame paste, can be positive in some patients with negative SPT to commercial seed preparation.
According to the authors, “With the increasing inclusion of seeds in many foods and the global popularity of various ethnic foods, seed allergy is expected to increase…. Until specific immunotherapy protocols are developed, management is basically strict avoidance which can be difficult considering the often hidden incorporation of such seeds in diet.”
- Patel A, Bahna SL. Hypersensitivities to sesame and other common edible seeds. Allergy. 21 June 2016. DOI: 10.1111/all.12962