Beneficial effects of green cardamom on serum SIRT1, glycemic indices and triglyceride levels in patients with type 2 diabetes mellitus: a randomized double-blind placebo controlled clinical trial.

Cardamom has antioxidant and anti-inflammatory effects which may help to remedy diseases. Studies on the health benefits of cardamom in diabetic patients are very limited. Thus, this study is designed to determine the effect of cardamom supplementation on blood lipids and glycemic indices in type 2 diabetic patients. To investigate the mechanism of cardamom effect on blood glucose and lipid levels, serum sirtuin-1 (SIRT1) was assessed.

In a parallel, double-blind randomized, placebo-controlled clinical trial, 83 overweight or obese type 2 diabetic patients were randomly allocated into an intervention (n = 41) or a control group (n = 42). The intervention and the placebo group received 3 g of green cardamom or rusk powder, respectively for 10 weeks. Physical activity level, dietary intake, anthropometric measurements (weight, height and waist circumference), glycemic indices [glucose, insulin, hemoglobin A1c (HbA1c)], blood lipids [triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c)] and SIRT1 levels were measured. Body mass index and homeostasis model assessment as an index of insulin resistance (HOMA-IR) were calculated before and after intervention. Compared to the control group, a significant decrease in serum HbA1C (-0.4%), insulin (-2.8 µIU dL^-1 ), HOMA-IR (-1.7) and TG (-39.9 mg dL^-1 ), and an increase in SIRT1 (2.3 ng mL^-1 ) was observed in cardamom group. There were no significant changes in serum TC, HDL-c and LDL-c levels between the two groups before and after adjustment for potential confounders including glyclaside dose, duration of disease and weight.

Our results showed that cardamom can decrease HbA1c, insulin level, HOMA-IR and TG level via increase in SIRT1 concentration in type 2 diabetes mellitus patients. © 2019 Society of Chemical Industry.