Gut Microbiota and Mental Health: Implications of the Gut-Brain Axis in Psychiatric Disorders

Abstract

Gut microbiota is a complex microbial ecosystem that regulates metabolic, immune, and neurophysiological functions, and its alteration has been associated with mental disorders. The objective of this study is to analyze the relationship between gut microbiota and mental health, assessing gut-brain axis mechanisms and potential therapeutic interventions. A systematic review of recent literature (2020–2025) was conducted using PubMed, Scopus, and Web of Science, including experimental animal studies, clinical trials, and meta-analyses related to gut microbiota, dysbiosis, and psychiatric disorders. The effects of probiotics, prebiotics, fecal microbiota transplantation, and functional diets were evaluated. Results show that the reduction of beneficial bacteria such as Firmicutes and Bacteroidetes, along with an increase in Proteobacteria, correlates with depression, anxiety, chronic stress, cognitive decline, and autism spectrum disorders. Probiotic and prebiotic interventions improve cognitive function, reduce depressive and anxious symptoms, and modulate inflammatory and neuroendocrine markers. Fecal microbiota transplantation also shows promising effects, although outcomes depend on donor selection and protocols. It is concluded that gut microbiota plays a crucial role in regulating the gut-brain axis and modulating mental disorders, and that therapeutic interventions aimed at restoring microbial balance have significant potential as complementary strategies in clinical practice.

Recepción: 11/09/2025

Aprobación: 04/12/2025