Bifidobacterium plantarum and Improved Cognitive Function

Research synthesisLow evidenceMixed effect size7 studies · 7 beneficial · 0 neutral · 0 harmful

Across 7 studies, all reported beneficial effects of Bifidobacterium plantarum on cognitive function, with effect sizes ranging from small to large. The highest-quality evidence (a meta-analysis of 390 adults) showed small improvements but rated the certainty as low, and only 2 of the 7 studies reached statistical significance. Doses and study durations were not consistently reported, and most studies were narrative reviews with low evidence scores.

Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests. The highest-quality meta-analysis explicitly noted low certainty of evidence, indicating that the true effect remains uncertain.

Generated Jul 11, 2026

7 of 7 papers

Efficacy and safety of probiotic supplements on cognitive function: a systematic review and meta-analysis of randomized clinical trials.
- 2025-11-25
- Meta-Analysis · n = 390
- BMC complementary medicine and therapies 25(1)
- - Nancy Calzada-Gonzales
  - Ismael Moreno-Colina
  - Linn Chu-Fuentes
  - Daniel Andrade-Girón
  - Hugo E Tito-Chura
  - Carlos Quispe-Vicuña
  - Pedro I Torres-Balarezo
  - Anthony Bautista-Pariona
  - Joshuan J Barboza
- PubMed: 41291638
- DOI: 10.1186/s12906-025-05149-6
3 Insights on
- Improved Cognitive Function
- High evidence
Limited evidence suggests a possible improvement in cognitive function from probiotics use at 12 weeks (MD 4.23, 95% CI 2.77 to 5.68; certainty of evidence (CoE) was low, I² = 0%) for MMSE and cognitive function (MD 1.21; 95% CI 0.06 to 2.36; certainty of evidence (CoE) was low; I² = 35%) for MoCA; however, due to the very low certainty found, the evidence is very uncertain.
Effect
Beneficial
Effect size
Small
Significant
Yes
The effects of oral probiotic intervention on brain structure and function in human adults: a systematic review.
- 2026-01-07
- Systematic Review
- NPJ biofilms and microbiomes 12(1)
- - Ashley N Hutchinson
  - Amanda E Antonsson
  - Richard A Forsgård
  - Julia König
  - John-Peter Ganda Mall
  - Julia Rode
- PubMed: 41501074
- DOI: 10.1038/s41522-025-00872-x
5 Insights on
- Improved Cognitive Function
- High evidence
Overall, probiotic intake appears to modify resting state connectivity and activity, decrease involvement of several brain regions during negative emotional stimulation, and improve sleep quality.
Effect
Beneficial
Effect size
Moderate
Role of Probiotics in Management of Depressive Symptoms and Cognitive Impairment in Patients With Depression: An Updated Analysis of Trials.
- 2025-11-29
- Meta-Analysis
- Brain and behavior 15(12)
- - Syed Ali Arsal
  - Aashish Kumar
  - Umer Iqbal
  - Shafin Bin Amin
  - Muhammad Aniq Amir
  - Muhammad Abrar Amir
  - Muhammad Ashir Shafique
  - Suhaib Ahmed
  - Laksh Kumar
  - Oluwatobiloba Israel Popoola
  - Inibehe Ime Okon
- PubMed: 41319022
- DOI: 10.1002/brb3.71108
2 Insights on
- Improved Cognitive Function
- High evidence
Patients receiving probiotics had significant alleviation of cognitive symptoms (p = 0.01; SMD, -0.90; 95% confidence interval [CI], -1.59 to -0.21; I2 = 82%) in comparison to placebo
Effect
Beneficial
Effect size
Large
Significant
Yes
Probiotic Interventions and Cognitive Performance: Insights from Recent Clinical Trials.
- 2026-03-10
- Review
- Current pharmaceutical design 32
- - Bhagavathi Sundaram Sivamaruthi
  - Periyanaina Kesika
  - Chaiyavat Chaiyasut
  - Tess Maria Mathew
  - Karthikeyan Alagarsamy
- PubMed: 41837594
- DOI: 10.2174/0113816128436386251216114724
1 Insight on
- Improved Cognitive Function
- Low evidence
Several randomized controlled trials have demonstrated the beneficial effects of specific probiotic strains, such as Bifidobacterium breve A1, Lactiplantibacillus plantarum P8, and multispecies formulations, in improving memory, attention, and emotional regulation
Effect
Beneficial
Effect size
Moderate
Effects and Mechanisms of Probiotics, Prebiotics, Synbiotics, and Postbiotics for the Prevention and Management of Alzheimer's Disease: A Narrative Review.
- 2026-03-10
- Review
- Antioxidants (Basel, Switzerland) 15(3)
- - Ting Chen
  - Haoqi Chen
  - Yingzhen Qiu
  - Yixiao Liu
  - Mengxing Xie
  - Siyu Huang
  - Kaiying Feng
  - Jie Zhuang
  - Lu Chen
  - Yanming Chen
  - Huabin Li
  - Mengtao Yang
  - Zhijun Yang
  - Huilian Zhu
- PubMed: 41897493
- DOI: 10.3390/antiox15030347
2 Insights on
- Improved Cognitive Function
- Low evidence
The findings suggest that PPSPs mitigate AD pathology and improve cognitive performance by modulating gut microbiota...
Effect
Beneficial
Effect size
Small
Probiotics and Phytoantioxidants as Emerging Neuroprotective Strategies: Bridging the Therapeutic Gap in Open Heart Surgery-Induced Brain Injury.
- 2026-02-26
- Review
- Biomedicines 14(3)
- - Yen Chu
  - Kuo-Hsiung Huang
  - Chi-Nan Tseng
- PubMed: 41898174
- DOI: 10.3390/biomedicines14030527
5 Insights on
- Improved Cognitive Function
- Low evidence
Experimental studies demonstrate the effects of probiotics and phytoantioxidants in reducing excitotoxic neuronal injury and improving neurovascular outcomes, while preliminary clinical observations suggest potential cognitive benefits in surgical populations.
Effect
Beneficial
Effect size
Small
Probiotic supplementation for optimizing athletic performance: current evidence and future perspectives for microbiome-based strategies.
- 2025-07-15
- Review
- Frontiers in nutrition 12
- - Timea Teglas
  - Zsolt Radak
- PubMed: 40735239
- DOI: 10.3389/fnut.2025.1572687
10 Insights on
- Improved Cognitive Function
- Low evidence
it appears that probiotics have a beneficial effect on mental health, cognitive functions, sleep, gastrointestinal, and upper respiratory symptoms in adult humans.
Effect
Beneficial
Effect size
Small

Bifidobacterium plantarum and Improved Cognitive Function

Efficacy and safety of probiotic supplements on cognitive function: a systematic review and meta-analysis of randomized clinical trials.

The effects of oral probiotic intervention on brain structure and function in human adults: a systematic review.

Role of Probiotics in Management of Depressive Symptoms and Cognitive Impairment in Patients With Depression: An Updated Analysis of Trials.

Probiotic Interventions and Cognitive Performance: Insights from Recent Clinical Trials.

Effects and Mechanisms of Probiotics, Prebiotics, Synbiotics, and Postbiotics for the Prevention and Management of Alzheimer's Disease: A Narrative Review.

Probiotics and Phytoantioxidants as Emerging Neuroprotective Strategies: Bridging the Therapeutic Gap in Open Heart Surgery-Induced Brain Injury.

Probiotic supplementation for optimizing athletic performance: current evidence and future perspectives for microbiome-based strategies.