The Effects of Probiotics Consumption on Blood Pressure, Lipid Profile, Glycemic Indices, and Inflammatory Parameters in Overweight and Obese Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Recent evidence suggests that probiotic supplementation might have beneficial impacts on improving obesity-related metabolic and inflammatory impairments in animal models and humans. This systematic review and meta-analysis aimed to review the existing literature about the effects of probiotics on blood pressure, glycemic control, lipid profile, inflammatory factors, and C-reactive protein levels in people with overweight or obesity. Comprehensive research was conducted across various online databases, including PubMed/MEDLINE, Cochrane, EMBASE, SCOPUS, Web of Science, and ProQuest, as well as ClinicalTrials.gov, ISRCTN, and ICTRP registry platforms. Screening of reference lists was also carried out until March 2023 to identify any relevant randomized controlled trials focusing on the impacts of probiotics on cardiovascular risk factors in obesity, without any language restrictions. The accumulated studies underwent screening and exclusion based on predetermined criteria by four independent researchers. Following this, a meta-analysis was carried out for the determined groups and subgroups. Finally, the quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Twenty-six eligible randomized controlled trials, including 1755 overweight and obese adults, were included in the meta-analysis. Administration of probiotics led to a slight to low-sized beneficial effect on systolic blood pressure (SBP) (standardized mean difference [SMD] = -0.09; 95% CI: -0.45, 0.26;  = 0.605), diastolic blood pressure (DBP) (SMD = -0.27; 95% CI: -0.53, -0.02;  = 0.037), fasting plasma glucose (FPG) (SMD = -0.16; 95% CI: -0.26, 0.06;  = 0.002), fasting insulin (SMD = -0.22; 95% CI: -0.34, 0.00;  = 0.001), total cholesterol (TC) (SMD = -0.10; 95% CI: -0.20, -0.01;  = 0.039), Low-density lipoprotein- Cholesterol (LDL-C) (SMD = -0.11; 95% CI: -0.21, -0.01;  = 0.020), High-density lipoprotein- Cholesterol (HDL-C) (SMD = 0.07; 95% CI: -0.07, 0.20;  = 0.316), triglyceride (TG) (SMD = -0.15; 95% CI: -0.27, -0.02;  = 0.022), and C-reactive protein (CRP) (SMD = -0.34; 95% CI: -0.63, -0.05;  = 0.020). The findings of the present study indicate that oral supplementation with probiotics yields a small, yet statistically significant beneficial effect on blood pressure, glucose and lipid metabolism, and CRP concentration. However, it's important to note that the present evidence is not conclusive and further large-scale trials along with additional meta-analyses are warranted to fully evaluate the potential of probiotics as a new strategy for preventing cardiovascular risk factors in overweight and obesity. It's worth mentioning that this review has been registered on PROSPERO under the registration number CRD42022323003, ensuring transparency and accountability in the research process.