Lactobacillus helveticus Rosell-52 and Reduced Depression Symptoms

Research synthesisLow evidenceModerate effect4 studies · 4 beneficial · 0 neutral · 0 harmful

Across 4 studies, all reported beneficial effects of Lactobacillus helveticus Rosell-52 on depression symptoms, with effect sizes ranging from small to moderate. A 2025 meta-analysis of 7 RCTs found a significant moderate-sized reduction in depressive symptoms (SMD -0.55, p=0.03). The evidence base is small and drawn primarily from reviews and meta-analyses including multi-strain probiotics, so the specific contribution of this single strain is not fully isolated.

Studied populations: adults with depression; adults with cancer

Caveats: Evidence base is small (only 4 studies) — conclusions should be considered preliminary. 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). The highest-quality study (meta-analysis) reported high heterogeneity (I²=79%), indicating inconsistent effects across trials. Most data come from multi-strain probiotic interventions, making it difficult to attribute effects solely to Lactobacillus helveticus Rosell-52.

Generated Jun 11, 2026

4 of 4 papers

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
- Reduced Depression Symptoms
- High evidence
the probiotic group had a significant reduction in depressive symptoms compared to the placebo group (p = 0.03; SMD, -0.55; 95% CI, -1.04 to -0.06; I2 = 79%)
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Rewiring Mood: Precision Psychobiotics as Adjunct or Stand-Alone Therapy in Depression Using Insights from 19 Randomized Controlled Trials in Adults.
- 2025-06-17
- Review
- Nutrients 17(12)
- - Alexandra-Eleftheria Menni
  - Helen Theodorou
  - Georgios Tzikos
  - Ioannis M Theodorou
  - Eleni Semertzidou
  - Veroniki Stelmach
  - Anne D Shrewsbury
  - George Stavrou
  - Katerina Kotzampassi
- PubMed: 40573133
- DOI: 10.3390/nu17122022
4 Insights on
- Reduced Depression Symptoms
- Moderate evidence
- Rigorous Journal
Nineteen RCTs met the inclusion criteria, with all demonstrating a significant amelioration of depression status after probiotic/psychobiotic treatment... Probiotics, particularly multi-strain preparations and certain well-characterized single strains, seem to be noticeably beneficial in alleviating depressive symptoms in adults.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Probiotics for Anxiety and Depressive Symptoms in Cancer: A Systematic Review of Animal and Human Studies with Mechanistic Insights.
- 2025-12-25
- Review
- Microorganisms 14(1)
- - Zahra Amirkhanzadeh Barandouzi
  - Deborah Watkins Bruner
  - Yufen Lin
  - Hannah Choi
  - Layla R Zeki
  - Tobi Akangbe
  - Amruta Epari
  - Hongjin Li
- PubMed: 41597571
- DOI: 10.3390/microorganisms14010051
6 Insights on
- Reduced Depression Symptoms
- Low evidence
Some trials reported improvements in anxiety, and depressive symptoms, while others showed no significant differences compared with control groups.
Effect
Beneficial
Effect size
Small
Host-microbiome relationship in depression: can human induced pluripotent stem cells play a role in unravelling mechanisms?
- 2025-07-01
- Review
- NPJ biofilms and microbiomes 11(1)
- - Cristina Rosell-Cardona
  - John F Cryan
  - Gerard Clarke
  - Sarah Kittel-Schneider
- PubMed: 40595695
- DOI: 10.1038/s41522-025-00749-z
2 Insights on
- Reduced Depression Symptoms
- Low evidence
consuming Lactobacillus helveticus Rosell-52... has been associated with improvements in mood and stress-related outcomes in some studies, suggesting a potential role in depression research
Effect
Beneficial
Effect size
Small

Lactobacillus helveticus Rosell-52 and Reduced Depression Symptoms

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

Rewiring Mood: Precision Psychobiotics as Adjunct or Stand-Alone Therapy in Depression Using Insights from 19 Randomized Controlled Trials in Adults.

Probiotics for Anxiety and Depressive Symptoms in Cancer: A Systematic Review of Animal and Human Studies with Mechanistic Insights.

Host-microbiome relationship in depression: can human induced pluripotent stem cells play a role in unravelling mechanisms?