The Effect of Probiotics on Oxidized LDL Levels: A Systematic Review and Meta-Analysis of Clinical Trials

Abstract

Background It has been widely reported that the use of probiotics has beneficial effects on the prevention and treatment of a wide range of human diseases. Previous clinical trials have investigated the effect of probiotics on oxLDL, but the results are controversial.Objective This study aimed to conduct a systematic review and meta-analysis of clinical trials to assess the effect of probiotic consumption on oxLDL levels.Methods A comprehensive search was conducted in PubMed, ISI Web of Science, and Scopus using the appropriate search strategy. After the screening, seven studies comparing the effects of probiotic consumption with the control were included in the analysis. A random-effects analysis was used to estimate the overall effect size.Results Probiotic supplementation significantly reduced oxLDL (Hedge's: -1.18; 95 CI:-1.85, -0.52) compared to the control group. Subgroup analysis showed that reduction was greater in the unhealthy group compared to healthy subjects (-2.05 vs. -0.84). The results also showed that probiotic supplementation reduced TC by -14.77 mg/dl (95 CI: -24.46, -5.08), LDL-C by -10.03 mg/dl (95 CI: -16.05, -4.001), LDL-C/HDL-C ratio by -0.37 (95 CI: -0.66, 0.07), and TG by -14.86 mg/dl (95 CI: -23.45, -6.28) but the effects on HDL-C and glucose were not significant.Conclusion In this study, probiotic supplementation was found to improve oxLDL concentrations and have favorable effects on lipid profiles, but no significant positive effect on HDL-C and glucose was reported. However, the findings should be interpreted with caution due to the low number of included studies.