The effect of barberry (Berberis vulgaris L.) supplementation on blood pressure: A systematic review and meta-analysis of the randomized controlled trials

Abstract

Objective: We identified and quantified the results of randomized clinical trials by examining the effect of barberry supplementation on blood pressure. Methods: We conducted a comprehensive search in the medical bibliographic database up to May 2020 on randomized clinical trials investigating the effect of barberry supplementation on adult blood pressure. Intensive literature searches and data extraction according to a prefixed scheme was performed independently by two investigators. Results: Through 5 randomized clinical trial studies, 350 subjects with 175 cases for the intervention group and 175 cases for control group were included in our study. The intervention period ranged from 4 to 12 weeks. In general, barberry supplementation did not have a significant effect on systolic blood pressure (WMD: -4.15 mmHg; 95 CI: -10.3, 1.99, P = 0.185) and diastolic blood pressure (WMD: -1.22 mmHg; 95 CI: -6.26, 3.82, P = 0.635). Our study was heterogeneous and subgroup analysis did not eliminate heterogeneity. Conclusion: Totally, based on this study, we cannot conclude that barberry supplementation has beneficial effects on blood pressure. Also, all included studies had limitations such as different in geographical situations, Dietary of participants, health conditions, and pharmacological forms of berberis. Therefore, further study in this area is recommended.