Probiotic supplementation can positively affect anxiety and depressive symptoms: A systematic review of randomized controlled trials

In this 2016 systematic review, the databases Medline, PsycINFO, PubMed, Scopus, and Web of Science were searched for randomized controlled trials (published between January 1990 and January 2016) that investigated the effect of probiotic supplementation on depression and anxiety symptoms. Little support was found for the therapeutic use of probiotics in depression and anxiety from the ten trials included in this review (4 clinically diagnosed, 6 non-clinical). But the findings imply humans may benefit psychologically from these probiotics, despite the inconsistencies in methodologies between the included studies. Future studies are imperative now to add to the current knowledge on probiotics and its developmental, modulatory, and metagenomic impacts on the GI microbiota. [NPID: probiotics, gut-brain axis, gut microbiota, gut bacteria, microbiota, gut microbiome, stress, prebiotics, depression, anxiety, GI microbiota]

Year: 2016

Reference: Pirbaglou, M., Katz, J., de Souza, R. J., Stearns, J. C., Motamed, M., & Ritvo, P. (2016). Probiotic supplementation can positively affect anxiety and depressive symptoms: a systematic review of randomized controlled trials. Nutrition research (New York, N.Y.), 36(9), 889–898. https://doi.org/10.1016/j.nutres.2016.06.009

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