Sesame - Allergy

Allergy

Sesame seeds and sesame oil are a serious allergen to some people. Even some infants have been found to exhibit allergies to sesame. In Australia the occurrence of allergy to sesame seed was estimated to be 0.42 percent among all children, while in the United Kingdom the allergic reaction was found to affect 0.04 percent of adults. The occurrence of allergy to sesame in patients with some form of food allergy was found to be much higher than in the general population, ranging from 0.5 percent in Switzerland to 8.5 percent in Australia. In other words, allergy to sesame affects a small percentage of overall human population, but sesame allergy is high in people who already show symptoms of allergy to other foods.

The symptoms of sesame seed allergy can be classified into:

• Systemic reactions: Primarily presenting anaphylaxis characterized by symptoms including hives (urticaria), lip and eyelid swelling (angioedema ) sneezing, nasal itching, congestion, rhinorrhea, wheezing, cough, tightness of throat, hoarse voice, difficulty in breathing, abdominal pain, unconsciousness, shock with drop of blood pressure. In the systemic reactions can also be included severe reactions like dizziness, drowsiness, chills and collapse as has been reported in patients after ingestion of a falafel burger.
• Other symptoms: Facial or generalized redness (“flushing”), hives (urticaria) on smaller or larger parts of the body, swelling of the eyelids, lips or other parts of the face, itching of the eyes or of the skin in general, hay fever symptoms in the eyes and eczema. Respiratory symptoms observed include hay fever, asthma, cough, wheeze, or difficulty in breathing. Gastrointestinal symptoms: Itching in the mouth and/or tongue soon after chewing and ingesting (Oral allergy syndrome) and abdominal pain.

Amounts as low as 100 mg of sesame seeds or flour and 3 ml of oil can trigger allergic reactions in severe cases of sesame allergic individuals. Most patients, however, show allergic reactions after consuming 2–10 grams of sesame seeds or flour. The onset of the symptoms may occur within a few minutes up to 90 minutes after ingestion of a sesame seed product. Most patients had other allergic diseases such as asthma, hay fever, and eczema, and most patients also had a relative with an allergic disease. More than two thirds of the patients with sesame allergy also had food allergic reactions to other foods.

Prevalence of sesame allergy varies per country. While it is one of the three most common allergens in Israel, sesame allergy prevalence is considered small relative to other allergens in the United States. Some experts consider sesame allergies to have "increased more than any other type of food allergy over the past 10 to 20 years" in the United States. Such increasing prevalence led Canada to issue regulations that require food labels to note the presence of sesame.

In addition to products derived from sesame such as tahini and sesame oil, persons with sesame allergies are warned to stay away from a broad assortment of processed foods including baked goods, tempeh, and generic "vegetable oil." In addition to possible food sources, individuals allergic to sesame have been warned that a variety of non-food sources may also trigger a reaction to sesame, including adhesive bandages, cosmetics, hair care products, perfumes, soaps and sunscreens, drugs, some fungicides and insecticides, lubricants, ointments and topical oils, and pet food.

At least one study found that "standard skin and blood testing for food allergies doesn’t predict whether a child has true sesame allergy." In which case, a food challenge under the direction of a physician may be required to properly diagnose a sesame allergy.

There appears to be cross-reactivity between sesame allergens and peanut, rye, kiwifruit, poppy seed, and various tree nuts (such as hazelnut, black walnut, cashew, macadamia and pistachio).