Evidence map›Paper›PMID 41501907›Full record

SynthesisBMC psychology2026

Probiotic intake and mental health in healthy working adults: a systematic review and meta-analysis of randomized controlled trials.

Sihem Ben Fredj, Hela Kechiche, Asma Chouchen, Imen Akkari, Rim Ghammam, Nawel Zammit, Nour Douss, Afef Skhiri, Maher Maoua, Jihen Maatoug and 2 more

Abstract readSystematic ReviewMeta-Analysis
PubMed Full text at PMC Publisher
In one paragraph

Synthesis in BMC psychology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from 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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Sihem Ben FredjDepartment of Preventive Medicine "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia. benfredj.sihem@famso.u-sousse.tn.
Hela KechicheFaculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Asma ChouchenDepartment of Occupational Medicine, "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Imen AkkariDepartment of Gastrology, University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Rim GhammamDepartment of Preventive Medicine "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Nawel ZammitDepartment of Preventive Medicine "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Nour DoussFaculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Afef SkhiriDepartment of Preventive Medicine "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Maher MaouaDepartment of Occupational Medicine, University Hospital Sahloul of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4011, Tunisia.
Jihen MaatougCommunity and Preventive Medicine Department, Primary health Care Corporation, P.O. Box: 26555, Al Mina Street, Doha, Qatar.
Imed HarrabiDepartment of Preventive Medicine "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.
Olfa El MaalelDepartment of Occupational Medicine, "LR19SP03", University Hospital Farhat Hached of Sousse, Faculty of Medicine of Sousse, University of Sousse, Sousse City, 4000, Tunisia.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundWorkers face significant mental health challenges from stress, anxiety, and depression, impacting individuals, organizations, and society. Emerging research indicates a link between the gut microbiome and mental well-being, suggesting probiotics as a potential support. This study objectively evaluated probiotic supplementation's effects on depression, anxiety, stress, sleep, and related biological markers in this population.

methodsWe conducted a systematic review and meta-analysis following PRISMA 2020 guidelines. EMBASE, Cochrane Library, and PubMed were searched for randomized controlled trials assessing probiotic supplementation on a range of psychological outcomes. The primary outcomes were perceived symptoms of depression, anxiety, stress, and sleep quality. The secondary outcomes were physiological markers of mental health, such as cortisol and C-reactive protein levels, in working populations. Eligible studies included healthy employed adults (≥ 18 years), without psychiatric, neurodegenerative, genetic, infectious, or endocrine disorders, including pregnancy.

resultsTwelve studies involving 3,350 participants were incorporated. Probiotic consumption had a modest yet statistically significant positive effect on subclinical psychological outcomes, including symptoms of depression, anxiety, and stress, in healthy working adults (standardised mean difference (SMD) = -0.21, 95% CI [-0.34, -0.09], p = 0.001). These findings were maintained despite moderate statistical heterogeneity that was likely due to variations in probiotic strains, dosages, and duration of supplementation used. Moreover, the probiotic interventions were associated with a statistically significant reduction in cortisol levels, a key biomarker of physiological stress (SMD = -0.26, 95% confidence interval [CI] [-0.45, -0.08], p = 0.005). Conversely, no statistically significant effects were observed for probiotic supplementation on the C-reactive protein levels, a marker of systemic inflammation. However, due to the lack of available evidence, it was impossible to draw firm conclusions about the effects of probiotics on sleep quality and biomarkers of oxidative stress.

conclusionThis systematic review and meta-analysis provide preliminary evidence suggesting that probiotic supplementation may hold promise as an approach to improve mental well-being within working populations. However, further high-quality randomised controlled trials targeting this population are needed to determine the optimal probiotic strains, dosages, and treatment durations for addressing specific mental health outcomes.

trial registrationPROSPERO number CRD42024510170.

Indexed as

AnxietyDepressionMental HealthProbioticsStress, PsychologicalAdultHumansRandomized Controlled Trials as TopicAnxietyDepressionMental healthOxidative stressProbioticsSleep disordersStressWork

Identifiers

PMID41501907
PMCPMC12874913

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

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 Socratic graph.