The Effect of Berberis vulgaris (Barberry Fruit) on a Component of Metabolic Syndrome: A Randomized Clinical Trial

Background: The metabolic syndrome is associated with increased risks of cardiovascular diseases and diabetes mellitus. Objectives: As alternative medicine emerged worldwide, this study aimed to evaluate the efficacy of Berberis vulgaris (barberry fruit) in the treatment of metabolic syndrome. Methods: This is a randomized, placebo controlled, double-blind, trial with two treatment arms. A total of 60 patients with metabolic syndrome were randomly assigned to receive barberry or placebo tablets (one 550 mg tablets per day for 3 weeks). Total cholesterol, LDL, HDL, triglyceride, fasting blood sugar and hematocrit were measured before and after 21 days of treatment. Data were analyzed using Mann-Whitney U and paired t-test by SPSS (V.15) software. P-values < 0.05 were considered to be significant. Results: In the barberry group, there was a significant decrease in systolic blood pressure (pre-treatment 123.1 ± 13.1 vs. post-treatment 117.7 ± 13.2, P-value = 0.04), waist circumference (pre-treatment 105.9 ± 7.5 vs. post-treatment105 ± 7.7, P-value = 0.04) and hematocrit (pre-treatment 45 ± 3.6 vs. post-treatment 43.5 ± 2.7, P-value = 0.004) but other parameters did not change significantly. Serum cholesterol was significantly reduced after intervention in the barberry group (-17 ± 61.1 vs. 23.6 ± 45, P-value = 0.02). Conclusions: We observed a significant effect of barberry on systolic blood pressure and waist circumference. Further studies with larger samples are needed to longitudinally investigate the effect of metabolic syndrome.