The gut-brain axis and depressive symptoms: A systematic review of randomized clinical trials with probiotics

Abstract

Objective: Currently, the gut-brain axis has been highlighted as an important aspect for understan-ding behavior and mental illnesses. The present study aimed to analyze the effects of probiotic consumption on depressive symptoms and major depression. Methods: A review of randomized, double or triple blind and placebo-controlled trials, published between 2010 and 2020, was performed in Pub-Med, Science Direct and Google Scholar. Results: Eight articles were selected to compose the sample. Findings between studies are controversial, and indicate that a causal relation between probiotic consumption and relieve of depressive symptoms is not yet established. Conclusion: More randomized, double or triple blind, placebo-controlled trials are necessary to consistently verify the causal relation between probiotic consumption and relieve of depressive symptoms.