The Effect of Lactobacillus Consumption on Human Blood Pressure: a Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVES Previous clinical studies have shown controversial results regarding the effect of Lactobacillus supplementation on blood pressure (BP). The purpose of this systematic review and meta-analysis is to examine the effect of Lactobacillus consumption on BP. METHODS Eligible randomized controlled trials (RCTs) were searched from five electronic databases until May 2020. In total, 18 studies were included in our meta-analysis. Quality of the selected studies was assessed, and a random-effects model was used to calculate the overall effect sizes of weighted mean differences (WMD). This systematic review was registered in PROSPERO with the number: CRD42019139294. RESULTS Lactobacillus consumption significantly reduced systolic blood pressure (SBP) by -2.74 mmHg (95% confidence interval, -4.96 to -0.51) and diastolic blood pressure (DBP) by -1.50 mmHg (95% confidence interval, -2.44 to -0.56) when comparing with the control group. Subgroup analysis showed that type 2 diabetes mellitus (T2DM) patients, Asian individuals, or borderline hypertension participants were more sensitive to daily consumption of Lactobacillus. And the effect of Lactobacillus on BP-reduction was more significant in capsule form, with the dose was above 5 × 109 colony-forming unit (CFU)/day or lasted for more than 8 weeks. CONCLUSIONS Our present study suggests that Lactobacillus consumption in capsule form when the daily dose is above 5 × 109 CFU for more than 8 weeks can decrease SBP or DBP in T2DM patients, borderline hypertension participants or Asian individuals.