title: Serum 25-Hydroxyvitamin D Concentration Is Independently Inversely Associated with Insulin Resistance in the Healthy, Non-Obese Korean Population.
abstract: BACKGROUND
  We evaluated the associations between 25-hydroxyvitamin D (25(OH)D) concentrations in serum and insulin resistance in the healthy Korean population.
  
  
  METHODS
  We conducted this cross-sectional analysis in 1,807 healthy Korean people (628 men and 1,179 women) aged 30 to 64 years in the Cardiovascular and Metabolic Disease Etiologic Research Center study. All participants were assessed for 25(OH)D, fasting glucose, and insulin levels, and completed a health examination and lifestyle questionnaire according to standard procedures. Insulin resistance was defined as the homeostasis model assessment insulin resistance higher than the 75 percentile.
  
  
  RESULTS
  Compared to those in the highest tertile (≥14.3 ng/mL), the odds ratio (OR) for insulin resistance was 1.37 (95% confidence interval [CI], 1.01 to 1.86) for the 1st tertile (<9.7 ng/mL) and 1.19 (95% CI, 0.08 to 1.62) for the 2nd tertile (9.7 to 14.3 ng/mL) after adjusting for age, gender, waist circumference, alcohol consumption, smoking status, physical exercise, season, and cohort. After stratification of the subjects by adiposity, these associations remained only in non-obese subjects (lowest tertile vs. highest tertile, multivariable OR, 1.64; 95% CI, 1.05 to 2.56).
  
  
  CONCLUSIONS
  Serum 25(OH)D has an independent inverse association with insulin resistance in the healthy, non-obese Korean population, even among people with vitamin D insufficiency.
authors.affiliation: Department of Endocrinology and Metabolism, Kosin University College of Medicine, Busan, Korea.
authors.forename: So Young
authors.initials: SY
authors.lastname: Ock
authors.affiliation: Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Korea.|Cardiovascular and Metabolic Disease Etiology Research Center, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Kyoung Hwa
authors.initials: KH
authors.lastname: Ha
authors.affiliation: Department of Endocrinology and Metabolism, Kosin University College of Medicine, Busan, Korea.
authors.forename: Bu Kyung
authors.initials: BK
authors.lastname: Kim
authors.affiliation: Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.|Cardiovascular and Metabolic Diseases Etiology Research Center, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyeon Chang
authors.initials: HC
authors.lastname: Kim
authors.affiliation: Cardiovascular and Metabolic Diseases Etiology Research Center, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jee Seon
authors.initials: JS
authors.lastname: Shim
authors.affiliation: Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea.|Cardiovascular and Metabolic Diseases Etiology Research Center, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Myung Ha
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Cardiovascular and Metabolic Diseases Etiology Research Center, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Me
authors.initials: YM
authors.lastname: Yoon
authors.affiliation: Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon, Korea.|Cardiovascular and Metabolic Disease Etiology Research Center, Ajou University School of Medicine, Suwon, Korea. djkim@ajou.ac.kr.
authors.forename: Dae Jung
authors.identifier: http://orcid.org/0000-0003-1025-2044
authors.initials: DJ
authors.lastname: Kim
keywords: Insulin resistance; Obesity; Vitamin D