Effects of probiotic supplementation on depression, anxiety, and sleep quality in healthy participants: A systematic review and meta-analysis
- 1Department of Pharmacy, the Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan Province 646000, China; School of Pharmacy, Southwest Medical University, Luzhou, Sichuan Province, 646000, China
- 2Department of Traditional Chinese Medicine, the Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan Province, 646000, China; Correspondence to: 25 Taiping Street, Jiangyang District, Luzhou City, Sichuan Province, China.
- 3Department of Pharmacy, the Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan Province 646000, China; Correspondence to: 25 Taiping Street, Jiangyang District, Luzhou City, Sichuan Province, China.
Abstract
This systematic review and meta-analysis evaluated the effects of probiotic supplementation on depression, anxiety, and sleep quality in healthy adults. PubMed, Cochrane Library, Web of Science, and Embase were searched from inception to September 18, 2026. Randomized controlled trials (RCTs) comparing probiotics with placebo for ≥ 4 weeks were included. Data from 20 studies involving 1508 participants were analyzed using Stata 17.0. Random-effects or fixed-effects models were selected according to heterogeneity. The GRADE approach was used to assess evidence certainty. Probiotics significantly reduced depression scores (SMD = −0.23, 95% CI: −0.36 to −0.10, P < 0.01; I² = 4.67%) and improved sleep quality (SMD = −0.37, 95% CI: −0.52 to −0.22, P < 0.01; I² = 41.67%). However, the overall effect on anxiety was not significant (SMD = −0.11, 95% CI: −0.31–0.09, P = 0.27; I² = 61.41%). Subgroup analyses were exploratory and unadjusted; no definitive conclusion can be drawn regarding intervention duration or strain type. GRADE certainty was moderate for depression and sleep quality, but very low for anxiety. In conclusion, probiotic supplementation may alleviate depressive symptoms and improve sleep quality in healthy adults, whereas its effect on anxiety remains inconclusive. Larger, standardized RCTs are needed to confirm these findings and clarify strain-specific effects.
Related
- What is the impact of oral probiotic supplementation on the HOMA-IR insulin resistance index in pregnant women with gestational diabetes mellitus without antidiabetic medication during the current pregnancy? A systematic review and meta-analysis
- Comparative efficacy of digital health intervention delivery modalities on quality of life, anxiety, and depression in coronary heart disease: a systematic review and network meta-analysis
- Temporal associations between pain and anxiety/depression in young people: A systematic review and meta-analysis of longitudinal, prospective, population- and community-based studies
- Prevalence of depression and anxiety among patients with Behçet's disease: a systematic review and meta-analysis.
- In randomized controlled trials with nutrient supplementation, participants with subjective memory complaints should not be combined with those having a mild cognitive impairment diagnosis
BibTeX
@article{liu2026effects,
title = {{Effects of probiotic supplementation on depression, anxiety, and sleep quality in healthy participants: A systematic review and meta-analysis}},
author = {Qinhan Liu and Ling Zhang and Yaomin Wang and Jun Li and Yaling Li},
journal = {Pharmacological Research},
year = {2026},
month = oct,
doi = {10.1016/j.phrs.2026.109716},
url = {https://doi.org/10.1016/j.phrs.2026.109716},
note = {CC BY},
}
RIS
TY - JOUR
TI - Effects of probiotic supplementation on depression, anxiety, and sleep quality in healthy participants: A systematic review and meta-analysis
AU - Qinhan Liu
AU - Ling Zhang
AU - Yaomin Wang
AU - Jun Li
AU - Yaling Li
PY - 2026
DA - 2026/10/31
JO - Pharmacological Research
DO - 10.1016/j.phrs.2026.109716
UR - https://doi.org/10.1016/j.phrs.2026.109716
AB - This systematic review and meta-analysis evaluated the effects of probiotic supplementation on depression, anxiety, and sleep quality in healthy adults. PubMed, Cochrane Library, Web of Science, and Embase were searched from inception to September 18, 2026. Randomized controlled trials (RCTs) comparing probiotics with placebo for ≥ 4 weeks were included. Data from 20 studies involving 1508 participants were analyzed using Stata 17.0. Random-effects or fixed-effects models were selected according to heterogeneity. The GRADE approach was used to assess evidence certainty. Probiotics significantly reduced depression scores (SMD = −0.23, 95% CI: −0.36 to −0.10, P < 0.01; I² = 4.67%) and improved sleep quality (SMD = −0.37, 95% CI: −0.52 to −0.22, P < 0.01; I² = 41.67%). However, the overall effect on anxiety was not significant (SMD = −0.11, 95% CI: −0.31–0.09, P = 0.27; I² = 61.41%). Subgroup analyses were exploratory and unadjusted; no definitive conclusion can be drawn regarding intervention duration or strain type. GRADE certainty was moderate for depression and sleep quality, but very low for anxiety. In conclusion, probiotic supplementation may alleviate depressive symptoms and improve sleep quality in healthy adults, whereas its effect on anxiety remains inconclusive. Larger, standardized RCTs are needed to confirm these findings and clarify strain-specific effects.
SN - 1096-1186
ER -