Vitamin D Intake and Status Are Associated with Lower Prevalence of Metabolic Syndrome in U.S. Adults: National Health and Nutrition Examination Surveys 2003–2006

Abstract

Previous reports have shown that metabolic syndrome and some metabolic syndrome components are associated with serum 25-hydroxyvitamin D [25(OH)D]. Using the National Health and Nutrition Examination Surveys (NHANES), 2003-2006, we evaluated the associations of vitamin D intake (n=3543) and vitamin D status [25(OH)D; n=3529], with the prevalence of metabolic syndrome and its components in adults 20 years and older. Exclusion criteria included nonfasted subjects, those pregnant and/or lactating, and, for intake analyses, those with unreliable 24-h recall records. Subjects were separately classified into quartiles of vitamin D intake (both including and excluding supplements) and serum 25(OH)D. Logistic regression was used to determine odds ratios (OR) for metabolic syndrome after adjusting for multiple confounders. Those in the highest quartile of serum 25(OH)D had 60% lower odds for metabolic syndrome as compared to those in the lowest quartile [OR=0.40; 95% confidence interval (CI) 0.27, 0.59]. Elevated waist circumference (OR=0.57; 95% CI 0.39, 0.84), low high-density lipoprotein cholesterol (HDL-C) (OR=0.54; 95% CI 0.39, 0.75), and high homeostasis model assessment of insulin resistance (HOMA-IR) (OR=0.40; 95% CI 0.29, 0.55) were the main components associated with serum 25(OH)D. Compared with the lowest vitamin D intake quartile (excluding supplements), those in the highest intake quartile had 28% lower odds for metabolic syndrome (OR=0.72; 95% CI 0.58, 0.90). No components of metabolic syndrome were significantly associated with dietary intake of vitamin D with supplements included or excluded. We conclude that higher 25(OH)D, and, to a lesser degree, greater dietary vitamin D intake, are associated with reduced prevalence of metabolic syndrome.