# Nutrition and Gut Microbiome in the Prevention of Food Allergy

## TL;DR

This review explores how nutrition and gut microbes may help prevent food allergies, but finds mixed results from current studies.

## Contribution

The paper systematically reviews recent trials on probiotics, prebiotics, and synbiotics for food allergy prevention.

## Key findings

- Most trials found no significant reduction in IgE-mediated food allergy with probiotics, prebiotics, or synbiotics.
- Early exposure to allergenic foods and Lactobacillus rhamnosus GG showed some promise in preventing cow’s milk allergy.
- Study design inconsistencies limit the generalizability of results.

## Abstract

Background: Food allergies are increasingly recognized as a global health concern, influenced by early-life nutrition and the gut microbiome. This systematic review examined randomized controlled trials from 2005 to 2025 assessing the effects of probiotics, prebiotics, and synbiotics in preventing food allergies. Methods: Fourteen studies involving 5685 participants, including pregnant women, infants, and children with or without diagnosed food allergies, were analyzed. While several interventions demonstrated modulation of gut microbiota and immune responses, most trials reported no statistically significant reduction in IgE-mediated food allergy compared with placebo. Results: Some evidence suggested benefits from early exposure to allergenic foods and specific probiotic strains, such as Lactobacillus rhamnosus GG, particularly in cow’s milk allergy. However, heterogeneity in study designs, strains, dosages, and diagnostic criteria limited generalizability. Conclusions: Overall, microbiome-targeted nutritional interventions show biological plausibility but inconsistent clinical efficacy. Future large-scale, standardized, and mechanistic studies integrating microbiome, genetic, and environmental data are warranted to define optimal strategies for allergy prevention.