From intake to impact: dietary modulation of the gut-brain axis across health and neurological disease.

The gut-brain axis (GBA) is an intricate, bidirectional communication network linking the gastrointestinal microbiota to the central nervous system. Mounting evidence underscores its critical role in the pathogenesis of neurological and neurodegenerative disorders. Diet serves as a primary modulator of this axis, possessing the capacity to profoundly reshape microbial diversity, metabolic output, and host-microbiota interactions. This review highlights the modulatory effects of distinct dietary patterns-specifically the Western, Mediterranean, and Ketogenic diets-on GBA signaling and overall neurological health. We comprehensively analyzed how these diets alter gut microbiota composition, influence the production of neuroactive microbial metabolites, and regulate neuroimmune signaling pathways. Furthermore, the mechanistic correlations between diet-driven microbiota alterations and the pathophysiology of neurodegenerative diseases were explored. By evaluating preclinical data on the neuroprotective potential of specific dietary components, this review underscores the therapeutic promise of microbiome-targeted dietary interventions while critically addressing the translational challenges for clinical application.