Inter-relationship of the Intestinal Microbiome, Diet, and Mental Health

Purpose of the Review: An unbalanced microbiota (dysbiosis) has been associated with or causative for a large array of human pathologies, including cognitive/emotional-related disorders. This review focuses on recent findings that address the restoration of a dysbiotic microbiota by dietary interventions with the main purpose of influencing brain function. Recent Findings: Recent research strongly suggests a critical connection between dietary habits, cognitive performance, and microbiota, but a thorough study of this inter-relationship presents a significant challenge. Although gut microbiota composition may be altered by environmental variables, it is fairly stable during adulthood and old age, and the analysis of gut microbial composition is not enough to fully understand the impact of a nutritional intervention in the gut microbiota and its consequences on the brain. Novel findings suggest the need for including the analysis of the metabolome and specific biomarkers of the microbial metabolism for the understanding of the effect of nutritional interventions on brain function. Summary: This review explores evidences pointing towards diet having a pivotal impact on the host’s development and progression of mental disorders through the regulation of microbiota composition and functionality. It is also discussed the role of key microbial metabolites as essential biomarkers to a better understanding of the complexity of the inter-relationship between microbiota, diet, and mental health. © 2018, Springer International Publishing AG, part of Springer Nature.