SynthesisCMAJ open
The effect of interventions targeting gut microbiota on depressive symptoms: a systematic review and meta-analysis.
Synthesis in CMAJ open. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers, 7 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
26 citing papers in PubMed, 7 syntheses or guidelines pooled it, 48 citations in OpenAlex.
- The effects of oral probiotic intervention on brain structure and function in human adults: a systematic review.NPJ biofilms and microbiomes · 2026Pooled it
- Effects of Prebiotics and Probiotics on Symptoms of Depression and Anxiety in Clinically Diagnosed Samples: Systematic Review and Meta-analysis of Randomized Controlled Trials.Nutrition reviews · 2025Pooled it
- Efficacy and safety of gut microbiome-targeted treatment in patients with depression: a systematic review and meta-analysis.BMC psychiatry · 2025Pooled it
- Clinical efficacy of fecal microbiota transplantation in alleviating depressive symptoms: a meta-analysis of randomized trials.Frontiers in psychiatry · 2025Pooled it
- Probiotics as a Tool for Regulating Molecular Mechanisms in Depression: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.International journal of molecular sciences · 2023Pooled it
- The current state of research for psychobiotics use in the management of psychiatric disorders-A systematic literature review.Frontiers in psychiatry · 2023Pooled it
- The Gut Microbiome in Depression and Potential Benefit of Prebiotics, Probiotics and Synbiotics: A Systematic Review of Clinical Trials and Observational Studies.International journal of molecular sciences · 2022Pooled it
- The Safety, Efficacy, and Feasibility of Fecal Microbiota Transplantation in a Population With Bipolar Disorder During Depressive Episodes: A Pilot Parallel Arm Randomized Controlled Trial: Sécurité, efficacité et faisabilité de la transplantation de microbiote fécal chez une population atteinte de troubles bipolaires, au cours d'épisodes dépressifs : essai pilote contrôlé à répartition aléatoire et à groupes parallèles.Canadian journal of psychiatry. Revue canadienne de psychiatrie · 2026Trial
- Gut microbiota-targeted interventions for depression in adolescents and young adults: Mechanisms, evidence strength and clinical strategies-A narrative review.General psychiatry · 2026Review
- Tryptophan metabolism in glaucomatous optic neuropathy: from metabolic dysregulation to therapeutic opportunities.Journal of translational medicine · 2026Review
- Psychobiotics in Mental Health - Between Hope, Evidence, and the Need for Precision.Alpha psychiatry · 2026Article
- Linking Obesity and Depression Through the Gut-Brain Axis: The Impact of Short-Chain Fatty Acids and Inflammation.Nutrients · 2026Review
- "Attacking" the Gut-Brain Axis with Psychobiotics: An Umbrella Review of Depressive and Anxiety Symptoms.Pharmaceuticals (Basel, Switzerland) · 2026Review
- Harnessing Dietary Tryptophan: Bridging the Gap Between Neurobiology and Psychiatry in Depression Management.International journal of molecular sciences · 2026Review
- Zinc and Cobalt exposure influencebioRxiv : the preprint server for biology · 2025Article
- A comprehensive overview of the effects of probiotics, prebiotics and synbiotics on the gut-brain axis.Frontiers in microbiology · 2025Review
- Gut microbiota as a novel target for treating anxiety and depression: from mechanisms to multimodal interventions.Frontiers in microbiology · 2025Review
- Gut microbiota, nutrients, and depression.Frontiers in nutrition · 2025Review
- Patient Perceptions of Microbiome-Based Therapies as Novel Treatments for Mood Disorders: A Mixed Methods Study: Perceptions des patients sur les thérapies basées sur le microbiome pour les troubles de l'humeur : une étude à méthodes mixtes.Canadian journal of psychiatry. Revue canadienne de psychiatrie · 2024Observational
- Butyrate- and Beta-Hydroxybutyrate-Mediated Effects of Interventions with Pro- and Prebiotics, Fasting, and Caloric Restrictions on Depression: A Systematic Review and Meta-Analysis.Life (Basel, Switzerland) · 2024Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
11 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundDespite their popularity, the efficacy of interventions targeting gut microbiota to improve depressive symptoms is unknown. Our objective is to summarize the effect of microbiome-targeting interventions on depressive symptoms.
methodsWe conducted a systematic review and meta-analysis. We searched MEDLINE, Embase, PsycINFO, Database of Abstracts of Reviews of Effects, Cochrane Database of Systematic Reviews and the Cochrane Controlled Register of Trials from inception to Mar. 5, 2021. We included studies that evaluated probiotic, prebiotic, synbiotic, paraprobiotic or fecal microbiota transplant interventions in an adult population (age ≥ 18 yr) with an inactive or placebo comparator (defined by the absence of active intervention). Studies must have measured depressive symptoms with a validated scale, and used a randomized controlled trial study design. We conducted a random effects meta-analysis of change scores, using standardized mean difference as the measure of effect.
resultsSixty-two studies formed the final data set, with 50 included in the meta-analysis. Probiotic, prebiotic, and synbiotic interventions on depressive symptoms showed statistically significant benefits. In the single studies evaluating each of fecal microbiota transplant and paraprobiotic interventions, neither showed a statistically significant benefit.
interpretationDespite promising findings of benefit of probiotic, prebiotic and synbiotic interventions for depressive symptoms in study populations, there is not yet strong enough evidence to favour inclusion of these interventions in treatment guidelines for depression. Critical questions about species administered, dosage and timing relative to other antidepressant medications remain to be answered. STUDY REGISTRATION: PROSPERO no. 143178.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.