Global rise in food allergy prevalence

Research into the rising prevalence of food allergies identifies a complex interplay of genetic, environmental, and lifestyle factors. Genetic predisposition remains a major driver, with the risk to children increasing to 40% if one parent is allergic and 80% if both are.

Biological factors, particularly alterations in intestinal microbiota, are central to the issue. Reduced microbial diversity in early life—potentially linked to antibiotic use, cesarean births, shorter breastfeeding durations, and delayed introduction of allergenic foods—is a key concern. In adults, changes in gut microbiota and the consumption of ultra-processed foods may further disrupt immune regulation. Recent research published in JAMA Pediatrics, analyzing 2.8 million children across 40 countries, identified infant eczema (atopic dermatitis) as a major risk factor, with affected children facing nearly four times the odds of developing food allergies.

Further biological studies, such as the COCOA study, have identified specific epigenetic and inflammatory markers in children with persistent allergies, including hypermethylation of the RPS6KA2 and GCSAML genes, lower levels of the regulatory cytokine IL-10, and elevated Th2 cytokines.

Environmental and industrial factors also contribute. These include air pollution, climate change, pesticide exposure, and the use of food additives. In Spain, data from the Spanish Society of Allergology and Clinical Immunology suggests one in four people suffers from some form of allergy disorder, with industrial processes potentially increasing the aggressiveness of certain food proteins.