Gut Microbiota and Food Allergy: Mechanistic Pathways, Early-Life Programming, and Microbiota-Targeted Strategies

Food allergies have emerged as a pressing global health concern, particularly in industrialized countries. Recent advances in immunology and microbiome research highlight the critical role of gut microbiota in modulating immune responses and shaping susceptibility to food allergies. Dysbiosis in microbial composition is increasingly associated with severe allergic responses and reduced immune regulatory activities. This review paper thoroughly examines the complex association between gut microbiota and food allergy, using latest human cohort research, animal models, and molecular insights. Key aspects addressed include early-life microbial colonization, immune system imprinting, and the role of microbial metabolites in immune tolerance. In addition to short-chain fatty acids (SCFAs), emerging modulators such as bile acids (acting through FXR and TGR5 pathways) and indole derivatives (activating the aryl hydrocarbon receptor to promote IL-22 production) are evaluated for their immunoregulatory potential. Emerging microbiome-targeted therapies, including probiotics, prebiotics, synbiotics, faecal microbiota transplantation (FMT), and tailored dietary regimens, are examined comprehensively for their therapeutic potential. Informed by a critical appraisal of 172 peer-reviewed studies published through 2025, this review identifies key microbial signatures of tolerance and proposes microbiota-targeted strategies for prevention and treatment. Emphasis is placed on early-life interventions and the integration of multi-omics platforms to translate microbial insights into clinically actionable solutions for managing food allergies