title: Association between serum vitamin D status and metabolic syndrome in Korean young men.
abstract: OBJECTIVE
  This study examined the relations of serum vitamin D levels to body fatness, cardiorespiratory fitness (CRF), and metabolic risk factors in young adults in Korea.
  
  
  METHODS
  Between 2007 and 2009, 799 young men completed a health examination. Body fatness, CRF based on a maximal treadmill exercise test, and measurements of metabolic risk factors were measured in study participants. Participants were classified by serum vitamin D levels as deficient (<12.5 ng·mL), insufficient (≥12.5 to <20 ng·mL), and sufficient (>20 ng·mL) and by CRF as unfit (lowest 20%) and fit (remaining 80%) based on age-standardized distribution of V˙O2max values in this study population. Body fatness, CRF, and metabolic risk factors were evaluated according to serum vitamin D classification. A clustered metabolic risk score was computed by summing standardized scores for waist circumference, resting blood pressures, triacylglycerols, the inverse of high-density lipoprotein cholesterol, glucose, and insulin.
  
  
  RESULTS
  Linear decreases in body fatness and metabolic risk factors were observed, as was a linear increase for CRF across incremental vitamin D categories. A linear decrease was found in the clustered metabolic risk score across incremental vitamin D categories. Compared to the fit group (reference), the unfit group had significantly higher risks for serum vitamin D inadequacy before and after adjusting for age, smoking, and body fatness parameters.
  
  
  CONCLUSIONS
  The findings of the study suggest that increasing vitamin D intake, eating a healthy diet, and getting enough outdoor physical activity should be promoted as nonpharmacologic means to improve CRF and prevent a clustering of metabolic risk factors in young adults.
authors.affiliation: 1College of Sport Science, Sungkyunkwan University, Suwon, REPUBLIC OF KOREA; and 2Pohang University of Science and Technology, Pohang, REPUBLIC OF KOREA.
authors.forename: Chang-Duk
authors.initials: CD
authors.lastname: Ha
authors.forename: Tae-Kyung
authors.initials: TK
authors.lastname: Han
authors.forename: Shin-Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Jin-Kyung
authors.initials: JK
authors.lastname: Cho
authors.forename: Hyun-Sik
authors.initials: HS
authors.lastname: Kang
mesh_terms: D000328:Adult; D001823:Body Composition / Q000502:physiology; D003430:Cross-Sectional Studies; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000209:etiology*; D016017:Odds Ratio; D010101:Oxygen Consumption; D010808:Physical Examination; D010809:Physical Fitness / Q000502:physiology; D056910:Republic of Korea; D012307:Risk Factors; D014807:Vitamin D / Q000097:blood* / Q000378:metabolism; D014808:Vitamin D Deficiency / Q000150:complications*; D055815:Young Adult
chemical_list: D014807:Vitamin D