Meta-analysis of randomized controlled trials of the effects of probiotics in Parkinson's disease

: Oral probiotic consumption significantly improved motor symptoms, gastrointestinal dysfunction, anxiety, and depression in patients with PD. Notably, oral probiotics also reduced the use of laxatives and increased GSH levels in the serum of patients with PD. In future studies, more high-quality evidence from large-scale RCTs is needed to determine the exact effects of probiotic treatment on PD.