Prevalence of tree nut allergy and exposure to tree nuts in children aged 1–12 years: An observational cohort study in the Netherlands

INTRODUCTION: Prevention of tree nut allergies requires understanding of regional prevalence, typical consumption patterns, and age of initial tree nut introduction. Despite guidelines advocating early introduction of allergenic foods (<12 months), data about early introduction and consumption patterns of tree nuts remains limited. AIM: To assess parent-reported prevalence of tree nut allergy and analyze tree nut consumption patterns, including age of first exposure: METHODS: An observational cohort study was conducted in the region of Limburg, in the Netherlands. Parents of children aged 1-12 years were invited to complete a digital questionnaire assessing parent-reported tree nut allergy and tree nut consumption patterns. RESULTS: Among 1867 respondents, 111 (5.9%) reported one or more tree nut allergies. The most reported are walnut (3.8%), hazelnut (3.3%), and cashew (3.2%). Most children had some exposure to tree nuts, but the frequency of consumption remains low. Only 24.2% report initial introduction of tree nuts in the first year of life, but this increased in younger children compared to older children in our cohort. Main reasons for tree nut consumption include perceived health benefits and allergy prevention; barriers include taste preferences, choking risk, known allergies, and product availability. CONCLUSION: Parent-reported tree nut allergy is relatively common, while tree nut consumption is limited and is often initially introduced after the age of 12 months. These findings highlight the need for targeted prevention strategies, particularly focused at hazelnut, walnut, and cashew, including clear guidance for parents and healthcare providers on safe early introduction of tree nuts.