Aim: To test the efficacy of a proprietary nutraceutical combination in reducing insulin resistance associated with the metabolic syndrome (MetS).
Methods: Sixty-four patients with MetS followed at a tertiary outpatient clinic were randomly assigned to receive either placebo or a proprietary nutraceutical combination (AP) consisting of berberine, policosanol and red yeast rice, in a prospective, double-blind, placebo-controlled study. Evaluations were performed at baseline and after 18 wk of treatment. The homeostasis model assessment of insulin resistance (HOMA-IR) index was the primary outcome measure. Secondary endpoints included lipid panel, blood glucose and insulin fasting, after a standard mixed meal and after an oral glucose tolerance test (OGTT), flow-mediated dilation (FMD), and waist circumference.
Results: Fifty nine patients completed the study, 2 withdrew because of adverse effects. After 18 wk there was a significant reduction in the HOMA-IR index in the AP group compared with placebo (ΔHOMA respectively -0.6 ± 1.2 vs 0.4 ± 1.9; P < 0.05). Total and low density lipoprotein cholesterol also significantly decreased in the treatment arm compared with placebo (Δlow density lipoprotein cholesterol -0.82 ± 0.68 vs -0.13 ± 0.55 mmol/L; P < 0.001), while triglycerides, high density lipoprotein cholesterol, and the OGTT were not affected. In addition, there were significant reductions in blood glucose and insulin after the standard mixed meal, as well as an increase in FMD (ΔFMD 1.9 ± 4.2 vs 0 ± 1.9 %; P < 0.05) and a significant reduction in arterial systolic blood pressure in the AP arm.
Conclusion: This short-term study shows that AP has relevant beneficial effects on insulin resistance and many other components of MetS.
Keywords: Berberine; Homeostasis model assessment index; Insulin resistance; Metabolic syndrome; Nutraceuticals.