Safflower (Carthamus tinctorius L.) oil could improve abdominal obesity, blood pressure, and insulin resistance in patients with metabolic syndrome: A randomized, double-blind, placebo-controlled clinical trial

Carthamus tinctorius L. (Safflower) has been widely recommended to treat metabolic disorders in traditional herbal medicine in Persia, China, Korea, Japan, and other East-Asian countries. The anti-hypercholesterolemic and antioxidant effects of this plant have been well documented, but its protective effects against Metabolic Syndrome (MetS) have not been fully illustrated.The present study aimed to evaluate the effects of safflower oil on MetS risk factors.In this randomized, double-blind, placebo-controlled clinical trial, 67 patients with MetS were administered either divided 8 g safflower oil or placebo daily for 12 weeks. All patients were advised to follow their previous diets and physical activities.Safflower oil resulted in a significant reduction in waist circumference (-2.42 ± 3.24 vs. 0.97 ± 2.53, p<0.001), systolic blood pressure (-8.80 ± 9.77 vs. -2.26 ± 8.56, p = 0.021), diastolic blood pressure (-3.53 ± 7.52 vs. -0.70 ± 6.21, p = 0.041), fasting blood sugar (-5.03 ± 10.62 vs. 2.94 ± 7.57, p = 0.003), and insulin resistance (-0.59 ± 1.43 vs. 0.50 ± 1, p = 0.012), but an increase in adiponectin level (0.38 ± 0.99 vs. -0.09 ± 0.81, p = 0.042) in the treatment group in comparison to the placebo group. The results revealed a direct relationship between leptin level and Body Mass Index (BMI) in both groups (p<0.001). In addition, increase in BMI resulted in a non-significant decrease in adiponectin level in both groups. Moreover, no significant difference was observed between the two groups regarding lipid profiles, leptin serum level, serum creatinine concentration, and other outcomes.Safflower oil without lifestyle modification improved abdominal obesity, blood pressure, and insulin resistance in patients with MetS.