The Effect of Prebiotics and Probiotics on Levels of Depression, Anxiety, and Cognitive Function: A Meta-Analysis of Randomized Clinical Trials

source extracted confidence: high 2026-04-09
#humans #probiotics #depression #anxiety #cognition

The Effect of Prebiotics and Probiotics on Levels of Depression, Anxiety, and Cognitive Function: A Meta-Analysis of Randomized Clinical Trials

Zandifar et al., 2025 | Brain Behav | Meta Analysis

Citation

Zandifar Atefeh, Badrfam Rahim, ... Pourjafar Hadi. The Effect of Prebiotics and Probiotics on Levels of Depression, Anxiety, and Cognitive Function: A Meta-Analysis of Randomized Clinical Trials. Brain Behav. 2025-Mar;15(3):e70401. doi:10.1002/brb3.70401

Abstract

INTRODUCTION: Recent studies have emphasized the relationship between mental health and the human intestine microbiota. In this study, we evaluate the effect of consuming Biotics, on levels of depression, anxiety, and cognitive function. METHODS: This meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. We searched MEDLINE (PubMed), Cochrane Library, Scopus, Web of Science, and ClinicalTrials.gov. All full-text articles and major reviews were manually searched for additional studies. RESULTS: The initial analysis was based on the concept that consuming Biotics causes changes in anxiety, measured using various instruments. This analysis showed that consuming Biotics significantly reduced anxiety in our study participants (SMD = 0.2894, Z = 2.46, P = 0.0139, I^2 = 92.4%). The meta-analysis included 4295 samples (2194 in the experimental group and 2101 in the control group). In terms of depression, the analysis showed that consuming Biotics significantly reduced depression in our study participants (SMD = 0.2942, Z = 2.13, P = 0.0335, I^2 = 91.7%). The meta-analysis included 3179 samples (1603 in the experimental group and 1576 in the control group). Regarding cognitive function, the analysis showed that consuming Biotics significantly improved cognitive function in our study participants (SMD = 0.4819, Z = 3.00, P = 0.0027, I^2 = 77.9%). The meta-analysis included 915 samples (470 in the experimental group and 445 in the control group). CONCLUSIONS: Our results indicate that most recent studies support the effectiveness of probiotics in reducing symptoms of anxiety, depression, and cognitive issues despite some discrepancies in the findings. People with mild symptoms may experience greater benefits from taking probiotics. TRIAL REGISTRATION: PROSPERO registration ID: CRD42024589507.

Key Findings

The initial analysis was based on the concept that consuming Biotics causes changes in anxiety, measured using various instruments. This analysis showed that consuming Biotics significantly reduced anxiety in our study participants (SMD = 0.2894, Z = 2.46, P = 0.0139, I^2 = 92.4%). The meta-analysis included 4295 samples (2194 in the experimental group and 2101 in the control group). In terms of depression, the analysis showed that consuming Biotics significantly reduced depression in our study

Outcomes Measured

  • anxiety
  • depression

Population

Field Value
Population See abstract
Sample Size 4295
Age Range See abstract
Condition anxiety

MeSH Terms

  • Humans
  • Probiotics
  • Depression
  • Anxiety
  • Cognition
  • Randomized Controlled Trials as Topic
  • Prebiotics
  • Gastrointestinal Microbiome

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Review
  • Vertical: probiotics-mood

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09