Logistic regression results showed that two groups, those with MetS defined by both definitions (OR = 6.07, 95% CI: 4.20–8.78) and those with MetS defined only by IDF (OR = 2.54, 95% CI: 1.52–4.23) were significantly more likely than the reference group (those without MetS) to have elevated fasting insulin. Here, INS is linked to metabolic syndrome.