Cowpea (Vigna unguiculata) is a legume that is widely cultivated and very important for the nutrition and health of millions of people, particularly in Africa, Asia, South America, and Southern Europe. Cowpea is emerging as a low-cost alternative protein in other regions raising concerns that its use in food may potentially put some legume-allergic people at risk.
A small study in Luxemburg identified four novel allergens in cowpea, among which storage proteins were found to play an important role. The study also sought to assess the cross-reactivity of cowpea with peanut allergy in people with legume allergies. Twenty-seven children (average age 6) were recruited to the trial and IgE-cross-reactivity between cowpea, pea, and peanut was determined using ELISA inhibition assays. Basophil activation tests were performed to evaluate sensitivity and reactivity of the participants’ basophils toward legumes.
Most participants with legume-allergy, mostly those with peanut allergy, were found to be sensitised to cowpea. Based on these results, the authors advise allergists to be aware of, potentially test for, and assess the risk presented by cowpea allergy, especially in people who are allergic to pea, lentil, and peanut.
With increasing use of cowpea protein as a plant-based protein alternative, cowpea joins the group of legumes that can cause allergic reactions but are not yet subjected to allergen labelling requirements, including chickpea, pea, and lentil.
Reference: Chentouh, MM, Codreanu-Morel, F, Boutebba, A, et al. Allergenic risk assessment of cowpea and its cross-reactivity with pea and peanut. Pediatr Allergy Immunol. 2022; 33:e13889. DOI: 10.1111/pai.13889. Open Access.