evidence table

Probiotics Depression Meta-Analysis Evidence Table

Structured evidence table for Probiotics Depression Meta-Analysis, generated from 2 reusable source documents in the Migaku knowledge base.

topicclaimevidence levelcitationsource
Probiotics Depression Meta-AnalysisProbiotic monotherapy was associated with a small but statistically significant reduction in depressive symptoms (SMD = -0.38, 95% CI: -0.57 to -0.18, p = 0.0002, I² = 51%).1Haiyan L (2026)Efficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
Probiotics Depression Meta-AnalysisConclusion Probiotic monotherapy may provide modest improvement in depressive symptoms and is generally safe for unmedicated individuals with mild to moderate depression.1Haiyan L (2026)Efficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
Probiotics Depression Meta-AnalysisObjective To assess the independent efficacy and safety of probiotics in unmedicated adults with depression, with a focus on studies approximating monotherapy conditions.1Haiyan L (2026)Efficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
Probiotics Depression Meta-AnalysisMethods This systematic review and meta-analysis followed PRISMA 2020 guidelines and was registered with PROSPERO (CRD420251015474).1Haiyan L (2026)Efficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
Probiotics Depression Meta-AnalysisConclusion In this randomized, double‑blind, placebo‑controlled pilot trial, both probiotic and placebo groups showed significant improvements in depressive and anxiety symptoms over time, with no significant between‑group differences.2Mosavat SH (2026)Effect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
Probiotics Depression Meta-AnalysisProbiotic supplementation was associated with non‑significant trends in selected inflammatory markers, suggesting possible immunological effects that warrant further investigation.2Mosavat SH (2026)Effect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
Probiotics Depression Meta-AnalysisBackground Substance-Induced Depressive Disorder (SIDD) accounts for a high health burden and requires new therapies.2Mosavat SH (2026)Effect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
Probiotics Depression Meta-AnalysisBidirectional communications between the gut and the brain mediated by the microbiota point to a possible influence of probiotics as a tool for preserving mental health.2Mosavat SH (2026)Effect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
topicProbiotics Depression Meta-Analysis
claimProbiotic monotherapy was associated with a small but statistically significant reduction in depressive symptoms (SMD = -0.38, 95% CI: -0.57 to -0.18, p = 0.0002, I² = 51%).
evidence level1
citationHaiyan L (2026)
sourceEfficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
topicProbiotics Depression Meta-Analysis
claimConclusion Probiotic monotherapy may provide modest improvement in depressive symptoms and is generally safe for unmedicated individuals with mild to moderate depression.
evidence level1
citationHaiyan L (2026)
sourceEfficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
topicProbiotics Depression Meta-Analysis
claimObjective To assess the independent efficacy and safety of probiotics in unmedicated adults with depression, with a focus on studies approximating monotherapy conditions.
evidence level1
citationHaiyan L (2026)
sourceEfficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
topicProbiotics Depression Meta-Analysis
claimMethods This systematic review and meta-analysis followed PRISMA 2020 guidelines and was registered with PROSPERO (CRD420251015474).
evidence level1
citationHaiyan L (2026)
sourceEfficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
topicProbiotics Depression Meta-Analysis
claimConclusion In this randomized, double‑blind, placebo‑controlled pilot trial, both probiotic and placebo groups showed significant improvements in depressive and anxiety symptoms over time, with no significant between‑group differences.
evidence level2
citationMosavat SH (2026)
sourceEffect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
topicProbiotics Depression Meta-Analysis
claimProbiotic supplementation was associated with non‑significant trends in selected inflammatory markers, suggesting possible immunological effects that warrant further investigation.
evidence level2
citationMosavat SH (2026)
sourceEffect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
topicProbiotics Depression Meta-Analysis
claimBackground Substance-Induced Depressive Disorder (SIDD) accounts for a high health burden and requires new therapies.
evidence level2
citationMosavat SH (2026)
sourceEffect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.
topicProbiotics Depression Meta-Analysis
claimBidirectional communications between the gut and the brain mediated by the microbiota point to a possible influence of probiotics as a tool for preserving mental health.
evidence level2
citationMosavat SH (2026)
sourceEffect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.

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Source documents

  1. Efficacy of probiotic intervention in unmedicated depression: a systematic review and meta-analysis.
  2. Effect of probiotic supplement on improvement of depressive symptoms in patients with substance-induced depressive disorder: a randomized, double-blind, placebo-controlled clinical trial.