Serum Zinc Concentration Is Inversely Associated with Insulin Resistance but Not Related with Metabolic Syndrome in Nondiabetic Korean Adults

Although zinc was known to be associated with insulin metabolism and diabetes, the relationship of serum zinc concentration with insulin resistance (IR) and metabolic syndrome (MetS) was not well investigated in general population. The aim of this study is to evaluate the relationships of serum zinc concentration with IR and MetS in a nondiabetic adult population. This cross-sectional study included 656 men and 825 women who were nondiabetic adults from the fifth Korea National Health and Nutrition Examination Survey conducted in 2010. Serum zinc concentration and metabolic parameters were measured. IR was estimated by homeostatic model assessment (HOMA2). MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Serum zinc concentration was negatively correlated with homeostasis model assessment for insulin resistance (HOMA2-IR) in men (r = −0.104, P = 0.008), but not in women. After adjusting for conventional cardiovascular risk factors, the inverse correlation was significant in both men and women (B = −0.262, SE = 0.060 for men, and B = −0.129, SE = 0.052 for women). However, serum zinc concentration was not different between the groups with and without MetS (P = 0.752 for men and P = 0.371 for women). In conclusion, serum zinc concentration was inversely associated with IR but not related to MetS in nondiabetic adult population.