Tree nuts and allergy: a review
In recent years, research has emphasized the health benefits of tree nuts, particularly in cardiovascular disease prevention, metabolic health, and neurological function. However, they are also among the most common food allergens, capable of triggering severe reactions, including anaphylaxis. Food allergies result from immune responses to food proteins, involving rapid mediator release, such as histamine.
Proteins are the primary allergens in tree nuts, with key families including seed storage proteins, lipid transfer proteins (LTPs), and pathogenesis-related proteins (PR-10). These proteins differ in stability during heat processing and digestion, affecting allergic reaction severity.
Almonds contain allergens Pru du 6 and Pru du 4, while Brazil nuts have Ber e 1, a seed storage protein. Walnuts’ major allergens, Jug r 1 (2S albumin) and Jug r 3 (LTP), contribute to cross-reactivity with hazelnuts and pecans. Hazelnuts contain Cor a 1 and Cor a 9, whereas cashews and pistachios, with Pis v 1 and Pis v 3, exhibit strong cross-reactivity with other tree nuts and seeds. Macadamia nuts, though allergenic, cause fewer reactions.
Despite their nutritional benefits, tree nuts present significant allergenic risks, varying across nut types. This review underscores the importance of balancing their health advantages with their potential to cause severe allergic responses.
Keywords: allergenic proteins, anaphylaxis, tree nut allergy, vegetal protein.
