Efficacy of Salvia officinalis extract on the prevention of insulin resistance in euglycemic patients with polycystic ovary syndrome: A double-blinded placebo-controlled clinical trial

•S. officinalis extract significantly improves anthropometric indices in patients with PCOS.•Insulin resistance markers in PCOS patients can be improved by consumption of S. officinalis extract.•S. officinalis can be used for prevention of metabolic complications in PCOS patients; however more studies are needed yet. At the present study, we aimed at evaluating the effect of Salvia officinalis (S. officinalis) extract on "anthropometric indices" and "insulin resistance markers" in Polycystic Ovary Syndrome (PCOS) patients. This was a randomized, triple-blinded, controlled trial performed in gynecology hospitals affiliated to Iran University of Medical Sciences. Sixty PCOS patients diagnosed according to Rotterdam criteria. Consumption of the 330 mg oral S. officinalis extract or placebo capsules daily for eight weeks. Body mass index (BMI), waist to hip ratio (WHR), blood pressure, homoeostatic model assessment-insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI). Results showed a statistically significant decrease in the BMI (P = 0.001) in S. officinalis group, but, there were no significant differences between the two groups for WHR (P = 0.164). Although we failed to find a significant effect of S. officinalis extract on systolic blood pressure (P = 0.283) but using a multivariate model showed a significant difference between two groups regarding diastolic blood pressure (P = 0.025). Also, the consumption of S. officinalis extract, compared to the placebo, resulted in a significant decrease in Insulin levels (P