Should You Worry About a Shea Butter Allergy?
By Dr. Ulrike Ziegner (Bio Below)
Potential food allergens lurk in sometimes unexpected places, as any seasoned food allergy patient can tell you. If you’re one of those patients, and you’ve been diagnosed with a tree nut allergy, you may have noticed tree nut ingredients in a non-food source: beauty products. Shea butter is one such ingredient, found not only in many confectionery food items, but in cosmetic and skin care products as well. Many patients with tree nut allergies question whether products containing shea butter are safe to use and wonder if they could have a shea butter allergy. So, let’s find out if one can be allergic to shea butter.
Is Shea Butter a Nut?
We’ll start with a basic understanding of the biology of an allergy. If you are allergic to a substance, it’s because your body’s immune system has mistakenly identified it (or a protein in it) as an invader. The immune system produces a specific antibody, called immunoglobulin E, or IgE, to fight the “invader”—your allergen—the next time you’re exposed to it. Many patients also experience a cross-reactive allergic response, in which the immune system recognizes a similar protein in another substance as an allergen. This is why it’s common for patients with an allergy to one tree nut, for example, to react to other types of tree nuts.
While foods are among the least common allergy triggers (the USDA estimates that approximately 2 percent of adults and up to 8 percent of children have a true food allergy), patients with food allergies are often especially vigilant about their condition—and with good reason. Food allergies can be especially dangerous, and doctors typically advise patients to carefully avoid exposure to their allergens. For those with a tree nut allergy, one of the most prevalent food allergies, that means avoiding all tree nut products, including nut oils and butters. Following the passage of the Food Allergen Labeling and Consumer Protection Act of 2004, which requires labeling of eight common food allergens—including tree nuts—the FDA issued a list of tree nuts subject to the labeling requirement, shea nuts among them. As of a January 2015 update, the FDA still considers the shea nut a tree nut, although the agency indicates that the list is based on “broad scientific categories,” not on whether a specific nut actually causes allergies.
Should you worry about an allergy to shea butter?
Probably not. The shea butter found in candy and beauty products is usually made from refined oil extracted from shea tree nuts. Unlike other nut butters (almond or cashew butter, for instance), which are protein-rich purees of whole nuts, the protein (the allergy-causing particle) in shea butter has been removed in the refining process, but not necessarily for raw or unrefined shea butter. One study identified extremely small amounts of protein in shea butter, but saw no IgE binding, that is, no allergy potential. In fact, there is no clinical evidence of allergy to shea butter—or to shea nuts, for that matter.
While the research suggests it is extremely unlikely, it is possible to develop a shea butter allergy. And some shea allergies can cause severe reactions, just as any allergen can. Based on one study’s findings, which suggest that applying another food-based oil, peanut oil, to the skin may lead to an allergy in certain circumstances, it might seem like shea butter could have the same result. Indeed, you can find numerous anecdotal reports of reactions to shea butter online from tree nut allergy patients. And citing a latex-like substance found in certain shea butter brands, some patients who are sensitive to latex also report cross-reactions. Still other patients use shea butter to treat allergy-related eczema, although there is no clear-cut scientific evidence of its potential anti-inflammatory properties.
Some self-reported reactions to shea butter can be found online, though may not be caused by an actual allergy. Many patients who believe they have an allergy to food, for example, actually have a sensitivity, and skin reactions are often simply non-allergic irritations. That’s why it’s so important to talk to your allergist if you have—or believe you may have—an allergy to food or any other substance. Your allergist will conduct tests to arrive at a proper diagnosis and, if necessary, help you develop a comprehensive, effective treatment and avoidance plan.
Bio: Ulrike Ziegner, MD, PhD is an Allergy and Asthma Specialist at Riviera Allergy Medical Center. She is board-certified with the American Board of Allergy & Immunology; American Board of Pediatrics and a fellow of the American College of Allergy, Asthma & Immunology; American Academy of Allergy, Asthma & Immunology; American Academy of Pediatrics. In her free time, Dr. Ziegner enjoys spending time with her family and friends, playing tennis and listening to classical music.