Lactobacillus brevis SBC8803 and Improved Sleep Quality

Research synthesisLow evidenceModerate effect7 studies · 7 beneficial · 0 neutral · 0 harmful

Across 7 studies, all 7 reported beneficial effects on sleep quality, with the predominant effect size being moderate. The evidence is drawn from a mix of RCTs, clinical trials, and reviews, with 3 studies reaching statistical significance. The most targeted study for this specific strain (Lactobacillus brevis SBC8803) was a small pilot crossover trial in 17 males with slightly high insomnia scores showing significant improvement in waking and marginal improvement in daytime drowsiness.

Studied populations: healthy adults with relatively high stress levels; male subjects (age 41-69 y) with slightly high Athens Insomnia Scale 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). Evidence base is small (only 7 studies) — conclusions should be considered preliminary. Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests. Only one direct clinical trial on the specific strain SBC8803 was identified (a pilot crossover study with 17 participants), with other positive studies coming from reviews or related strains.

Generated May 12, 2026

10 of 10 papers

Bifidobacterium adolescentis SBT2786 Improves Sleep Quality in Japanese Adults with Relatively High Levels of Stress: A Randomized, Double-Blind, Placebo-Controlled Study.
- 2024-05-30
- RCT · n = 65
- Nutrients 16(11)
- - Hiroki Murakami
  - Taro Ko
  - Haruka Ouchi
  - Toshiharu Namba
  - Shukuko Ebihara
  - Shunjiro Kobayashi
- PubMed: 38892634
- DOI: 10.3390/nu16111702
3 Insights on
- Improved Sleep Quality
- High evidence
- Rigorous Journal
SBT2786 increased sleep time; however, it predominantly increased light sleep and did not improve subjective sleep quality. Interestingly, mood improvement was observed. A subgroup analysis was conducted on participants with high stress levels, and results showed that these participants experienced an increase in sleep duration and an improvement in sleepiness upon waking up and reported feeling well-rested during the day.
Effect
Beneficial
Effect size
Moderate
Effect of Heat-Killed Lactiplantibacillus plantarum SNK12 on Sleep Quality and Stress-Related Neuroendocrine and Inflammatory Biomarkers in Adults: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Trial.
- 2025-12-24
- RCT
- Life (Basel, Switzerland) 16(1)
- - Takumi Watanabe
  - Shiho Kurosaka
  - Yuriko Namatame
  - Toshio Kawahara
- PubMed: 41598182
- DOI: 10.3390/life16010026
4 Insights on
- Improved Sleep Quality
- High evidence
Compared with placebo, SNK improved Sleepiness on Rising (p = 0.032) and Initiation and Maintenance of Sleep (p = 0.010).
Effect
Beneficial
Effect size
Small
Significant
Yes
Effect of dietary heat-killed Lactobacillus brevis SBC8803 (SBL88™) on sleep: a non-randomised, double blind, placebo-controlled, and crossover pilot study.
- 2016-09-01
- Clinical Trial · n = 17
- Beneficial microbes 7(4)
- - Y Nakakita
  - N Tsuchimoto
  - Y Takata
  - T Nakamura
- PubMed: 27013460
- DOI: 10.3920/bm2015.0118
3 Insights on
- Improved Sleep Quality
- High evidence
- Rigorous Journal
The sleep journals revealed an improvement in 'waking' for the SBC8803 consumption periods (P=0.047), and there was a marginally significant effect on 'drowsiness during the following day' (P=0.067).
Effect
Beneficial
Effect size
Small
Significant
Yes
Microbiome-Based Therapeutics for Insomnia.
- 2024-12-09
- Review
- International journal of molecular sciences 25(23)
- - Chenyu Li
  - Sizhe Chen
  - Yun Wang
  - Qi Su
- PubMed: 39684918
- DOI: 10.3390/ijms252313208
1 Insight on
- Improved Sleep Quality
- Moderate evidence
- Rigorous Journal
consuming Lactobacillus brevis SBC8803 improved sleep quality in healthy adults
Effect
Beneficial
Effect size
Moderate
Insomnia: the gut microbiome connection, prospects for probiotic and postbiotic therapies, and future directions.
- 2026-04
- Review
- Journal of advanced research 82
- - Qiong Wu
  - Guangqi Gao
  - Lai-Yu Kwok
  - Huimin Lv
  - Zhihong Sun
- PubMed: 40651630
- DOI: 10.1016/j.jare.2025.07.005
2 Insights on
- Improved Sleep Quality
- Low evidence
Probiotics and postbiotics are beneficial microorganisms and their components and metabolites, which offer potential in modulating the gut microbiota of the host and alleviating insomnia. ... Probiotics can regulate sleep-wake behavior by modulating gut microbiota and its metabolites, influencing endocrine, neuronal, and immune responses.
Effect
Beneficial
Effect size
Moderate
Microbiota Composition and Probiotics Supplementations on Sleep Quality-A Systematic Review and Meta-Analysis.
- 2023-12-13
- Review
- Clocks & sleep 5(4)
- - Daniele Santi
  - Valentina Debbi
  - Francesco Costantino
  - Giorgia Spaggiari
  - Manuela Simoni
  - Carla Greco
  - Livio Casarini
- PubMed: 38131749
- DOI: 10.3390/clockssleep5040050
1 Insight on
- Improved Sleep Quality
- Low evidence
probiotics supplementation significantly reduced the self-assessed parameter of sleep quality and disturbances Pittsburgh Sleep Quality Index (PSQI) score compared with the placebo. No difference in the Epworth Sleepiness Scale (ESS) score was found.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Lactobacillus fermentum PS150 promotes non-rapid eye movement sleep in the first night effect of mice.
- 2021-08-11
- Scientific reports 11(1)
- - Alexander Lin
  - Ching-Ting Shih
  - Hsu-Feng Chu
  - Chieh-Wen Chen
  - Yu-Ting Cheng
  - Chien-Chen Wu
  - Cheryl C H Yang
  - Ying-Chieh Tsai
- PubMed: 34381098
- DOI: 10.1038/s41598-021-95659-3
3 Insights on
- Improved Sleep Quality
- Low evidence
- Rigorous Journal
- Animal Study
intervention with PS150 restored non-rapid eye movement (NREM) sleep length under the FNE... PS150 efficiently reduced both sleep latency and time spent restoring normal levels of REM sleep
Effect
Beneficial
Effect size
Moderate
Dietary Heat-Killed Lactobacillus brevis SBC8803 Attenuates Chronic Sleep Disorders Induced by Psychophysiological Stress in Mice.
- 2019-04-30
- Clinical Trial
- Journal of Nutritional Science and Vitaminology 65(2)
- - Sayaka Higo-Yamamoto
  - Saori Yamamoto
  - K. Miyazaki
  - Y. Nakakita
  - H. Kaneda
  - Y. Takata
  - Takeshi Nakamura
  - K. Oishi
- PubMed: 31061285
- DOI: 10.3177/jnsv.65.164
9 Insights on
- Improved Sleep Quality
- Low evidence
- Animal Study
dietary SBC8803 suppressed the reduction in wheel-running activity induced by CSD. Electroencephalography (EEG) revealed that SBC8803 significantly restored wakefulness and increased non-rapid eye movement (NREM) sleep during the second half of the active phase during CSD. The CSD-induced reduction in EEG slow wave activity... was significantly improved by SBC8803 supplementation.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Hypnotic Effects of Lactobacillus fermentum PS150TM on Pentobarbital-Induced Sleep in Mice.
- 2019-10-09
- Nutrients 11(10)
- - Alexander Lin
  - Ching-Ting Shih
  - Chin-Lin Huang
  - Chien-Chen Wu
  - Ching-Ting Lin
  - Ying-Chieh Tsai
- PubMed: 31600934
- DOI: 10.3390/nu11102409
2 Insights on
- Improved Sleep Quality
- Low evidence
- Rigorous Journal
- Animal Study
PS150TM, but not the other L. fermentum strains, significantly decreased the sleep latency and increased the sleep duration of mice... PS150TM could attenuate a caffeine-induced sleep disturbance in mice
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Dietary Prebiotics and Bioactive Milk Fractions Improve NREM Sleep, Enhance REM Sleep Rebound and Attenuate the Stress-Induced Decrease in Diurnal Temperature and Gut Microbial Alpha Diversity.
- 2017-01-10
- Frontiers in behavioral neuroscience 10
- - Robert S Thompson
  - Rachel Roller
  - Agnieszka Mika
  - Benjamin N Greenwood
  - Rob Knight
  - Maciej Chichlowski
  - Brian M Berg
  - Monika Fleshner
- PubMed: 28119579
- DOI: 10.3389/fnbeh.2016.00240
5 Insights on
- Improved Sleep Quality
- Low evidence
Test diet, compared to control diet, increased fecal Lactobacillus rhamnosus CFU, facilitated non-rapid eye movement (NREM) sleep consolidation (PND 71/72) and enhanced rapid eye movement (REM) sleep rebound after stressor exposure (PND 87).
Effect
Beneficial
Effect size
Moderate