CHILDHOOD food allergy risk begins early, shaped by a complex interaction of genetic, environmental, and clinical factors, according to a large systematic review and meta-analysis. Analysing data from 190 studies involving approximately 2.8 million participants across 40 countries, researchers identified the most robust predictors of food allergy development before 6 years of age, offering new insights to guide prevention strategies and clinical decision-making.
Global Data Clarify Drivers of Childhood Food Allergy
Food allergy incidence confirmed by oral food challenge was estimated at 4.7%, highlighting the growing global burden of allergic disease in early life. The investigators assessed 342 potential risk factors, using multivariable analyses and rigorous evidence grading to determine which were most strongly associated with allergy onset.
Among the most influential predictors were early allergic conditions, supporting the concept of the “atopic march.” Infants with atopic dermatitis during the first year of life had nearly fourfold higher odds of developing food allergy, while allergic rhinitis and wheeze were also strongly linked. Biological markers of impaired skin barrier function, including increased transepidermal water loss and filaggrin gene sequence variations, emerged as key contributors, reinforcing the role of skin integrity in sensitisation pathways.
Modifiable early-life exposures were also identified. Delayed introduction of allergenic solid foods, particularly peanut after 12 months of age, was associated with increased risk, aligning with evolving infant feeding recommendations that encourage earlier allergen exposure. Antibiotic use in infancy and during pregnancy showed modest but notable associations, suggesting a potential role for microbiome disruption.
The analysis further highlighted demographic and familial influences. Male sex, being first born, family history of allergy, parental migration, and self-identification as Black were all linked to higher risk, while caesarean delivery showed a smaller but measurable association. In contrast, factors such as low birth weight, post-term birth, maternal diet, and prenatal stress were not significantly associated with food allergy development.
Implications for Prevention Strategies in Paediatric Allergy
Taken together, the findings suggest that childhood food allergy arises from a convergence of genetic susceptibility, early allergic disease, environmental exposures, and social determinants. The authors emphasise that recognising both major and minor risk factors may help clinicians identify infants at highest risk and implement earlier preventive interventions. As the prevalence of food allergy continues to rise globally, these results provide an important evidence base to inform future guidelines, policy decisions, and research aimed at reducing disease burden in children.
Reference
Islam N et al. Risk factors for the development of food allergy in infants and children: a systematic review and meta-analysis. JAMA Pediatr. 2026. doi:10.1001/jamapediatrics.2025.6105.
