Efficacy of probiotic supplementation in influencing cognitive function in Alzheimer's disease: A systematic review and meta-analysis

source extracted confidence: high 2026-04-09
#probiotics #humans #alzheimer-disease #cognition #aged

Efficacy of probiotic supplementation in influencing cognitive function in Alzheimer's disease: A systematic review and meta-analysis

Liu et al., 2025 | J Food Sci | Meta Analysis

Citation

Liu Weitong, Guo Jinghan, ... Wang Yanqing. Efficacy of probiotic supplementation in influencing cognitive function in Alzheimer's disease: A systematic review and meta-analysis. J Food Sci. 2025-Jul;90(7):e70037. doi:10.1111/1750-3841.70037

Abstract

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline and behavioral changes. Emerging evidence suggests that the gut microbiota influences central nervous system function. Probiotic interventions may offer a promising therapeutic approach by modulating the gut microbiota composition and potentially improving cognitive outcomes in AD patients. This meta-analysis aimed to assess the effects of probiotic supplementation on cognitive function in AD patients by analyzing randomized controlled trials (RCTs). Following PRISMA 2020 guidelines and registered with PROSPERO (CRD42024508725), we conducted a comprehensive search across PubMed, Embase, Cochrane Library, and ClinicalTrials.gov through April 9th, 2024. Only double-blind RCTs comparing probiotic supplementation to placebo in patients aged 65 or older with clinically diagnosed AD were included. Primary outcomes were cognitive function scores from validated tools like MMSE and TYM. Our stringent inclusion criteria identified four double-blind RCTs with 251 participants aged 65 or older with clinically diagnosed AD. Statistical analysis using a random-effects model revealed significant cognitive improvement in probiotic-treated groups compared to placebo controls (Standardized Mean Difference [SMD] = 0.67; 95% CI [0.14, 1.19]; P < 0.05), though substantial heterogeneity was observed (I2 = 79.16%). Subgroup analyses indicated that probiotic formulation type, dosage, and baseline AD severity may influence cognitive outcomes. While these findings suggest probiotics may offer cognitive benefits for AD patients, the high heterogeneity and limited study number necessitate additional well-designed clinical trials to confirm these promising results and establish optimal treatment protocols for clinical implementation.

Key Findings

While these findings suggest probiotics may offer cognitive benefits for AD patients, the high heterogeneity and limited study number necessitate additional well-designed clinical trials to confirm these promising results and establish optimal treatment protocols for clinical implementation.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size 251
Age Range See abstract
Condition cognitive

MeSH Terms

  • Probiotics
  • Humans
  • Alzheimer Disease
  • Cognition
  • Aged
  • Gastrointestinal Microbiome
  • Randomized Controlled Trials as Topic
  • Dietary Supplements
  • Male
  • Female
  • Aged, 80 and over

Evidence Classification

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

Provenance

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