The role of probiotics in the treatment of depressive disorders. A critical review

Depressive disorders are a widespread problem in modern medicine. According to current data from the World Health Organisation, an estimated 280 million people worldwide suffer from depression. In recent years, there have been reports of a correlation between the composition of the gut microbiota and the development of depressive disorders and attempts to modify it through the use of psychobiotics. The literature from the PubMed database published between 2018-2023 has been explored. 596 articles were selected based on the keywords "probiotics" and "depression". Six randomized clinical trials were finally included in the analysis. As defined elsewhere, psychobiotics are probiotic bacteria which supplemented in adequate amounts, interact with the gut-brain axis and show beneficial effects on patients' mental health. Results from recent RCTs suggest that daily probiotic supplementation significantly reduces the severity of depression compared to placebo (p