Is there a role of gut microbiota in mental health?

Research on the interaction between gut microbiota and the brain may have implications for our understanding of brain function, cognition, behavior and mental health. The literature on gut microbiota and its role in the pathophysiology and potential treatment of mental disorders has proliferated in recent years. Several neurodevelopmental disorders, including autism spectrum disorders, schizophrenia and attention-deficit/hyperactivity disorder, have been linked to the gut microbiota. The present perspective discusses the promise and pitfalls of gut microbiota research in relation to mental health. The manipulation of intestinal microbes in animals has revealed connections between gut microbiota and both normal and pathological brain functions. The hope fueling this research is that gut microbiota could be harnessed to prevent and treat mental disorders. The links observed between an imbalance of gut microbiota and impaired behavioral and mental states in humans are correlational. It is therefore essential to establish cause and effect relationships. No distinct gut microbiota patterns linked to different mental disorders have yet been identified. Large-scale, longitudinal trials need to examine whether the gut microbiota is a valid therapeutic target for mental disorders and whether pre-clinical findings and initial results of intervention trials (e.g., administration of probiotics) are of clinical relevance.