Both before and after adjusting for sex, plasma triglyceride (TG) (p < 0.001 both) (Fig. 1F) and serum leptin (p = 0.010 and p = 0.028, respectively) (Fig. 1I) were significantly higher, while quantitative insulin sensitivity check index (QUICKI) (p = 0.034 and p = 0.027, respectively) (Fig. 1D), plasma high-density lipoprotein cholesterol (HDL-C) (p < 0.001 both) (Fig. 1G), and serum adiponectin (p = 0.005 and p = 0.022, respectively) (Fig. 1K) were significantly lower in participants with MetS compared to those without MetS. Here, INS is linked to metabolic syndrome.