Associations Between Concentrations of Vitamin D and Concentrations of Insulin, Glucose, and HbA1c Among Adolescents in the United States

OBJECTIVE-Our objective was to examine the associations between concentrations of vitamin D and concentrations of insulin, glucose, and HbA(1c) in a nationally representative sample of adolescents in the U.S. RESEARCH DESIGN AND METHODS-We used data for 1,941 adolescents, aged 12-17 years, who participated in the National Health and Nutrition Examination Survey between 2001 and 2006. RESULTS-Adjusted concentrations of insulin were similar to 24% lower among male subjects with a concentration of vitamin D >= 75 nmol/L than among male subjects with a concentration of vitamin D < 50 nmol/L (P = 0.003). Concentrations of vitamin D were inversely associated with concentrations of glucose only among Mexican American male subjects (P = 0.007). No significant associations between concentrations of vitamin D and HbA(1c) were detected. CONCLUSIONS-Our results support an inverse association between concentrations of vitamin D and insulin primarily in adolescent male subjects.