The study looked at 32 studies over a 22-year period
In a new study published in the journal Allergy, researchers conducted a systematic review of studies on the prevalence of food allergy and food sensitization in Europe, in which they summarized the prevalence of tree nut allergy/sensitization to individual tree nuts.
The researchers searched for relevant papers published between 2000 and 2021 and identified a total of 32 studies. Although the review investigated all types of tree nuts —almond, Brazil nut, cashew, hazelnut, pistachio, pecan, pine nut, macadamia and walnut— meta-analysis was not possible in all cases.
The findings showed that self-reported lifetime prevalence was 0.8% for hazelnut and 0.4% for walnut. Self-reported point prevalence —that is, prevalence at the time of study— was 4.0% for hazelnut, 3.4% for Brazil nut, 2.0% for almond and 1.8% for walnut. Point prevalence of food-challenge-confirmed tree nut allergy was 0.04% for hazelnut and 0.02% for walnut.
This study provides the most comprehensive and up-to-date survey of the prevalence of specific tree nut allergies in Europe.
Spolidoro, G. C. I., Lisik, D., Nyassi, S., Ioannidou, A., Ali, M. M., Amera, Y. T., Rovner, G., Khaleva, E., Venter, C., van Ree, R., Worm, M., Vlieg-Boerstra, B., Sheikh, A., Muraro, A., Roberts, G., & Nwaru, B. I. (2024). Prevalence of tree nut allergy in Europe: A systematic review and meta-analysis. Allergy, 79(2), 302–323.