title: National Estimates of Serum Total 25-Hydroxyvitamin D and Metabolite Concentrations Measured by Liquid Chromatography-Tandem Mass Spectrometry in the US Population during 2007-2010.
abstract: The 2007-2010 NHANES provides the first US nationally representative serum 25-hydroxyvitamin D [25(OH)D] concentrations measured by standardized liquid chromatography-tandem mass spectrometry.
  
  
  
  We describe patterns for total 25(OH)D and individual metabolites in persons aged ≥1 y stratified by race-ethnicity and grouped by demographic, intake, physiologic, and lifestyle variables.
  
  
  
  We measured 25-hydroxycholecalciferol [25(OH)D3], 25-hydroxyergocalciferol [25(OH)D2], and C3-epimer of 25(OH)D3 [C3-epi-25(OH)D3] in serum samples (n = 15,652) from the 2007-2010 cross-sectional NHANES [total 25(OH)D = 25(OH)D3 + 25(OH)D2].
  
  
  
  Concentrations (median, detection rate) of 25(OH)D3 (63.6 nmol/L, 100%) and C3-epi-25(OH)D3 (3.40 nmol/L, 86%) were generally detectable; 25(OH)D2 was detectable in 19% of the population. Total 25(OH)D, 25(OH)D3, and C3-epi-25(OH)D3 displayed similar demographic patterns and were strongly correlated (Spearman's r > 0.70). Concentrations of 25(OH)D2 (90th percentile) were much higher in persons aged ≥60 y (17.3 nmol/L) than in younger age groups (≤4.88 nmol/L). We noted significant race-ethnicity differences in mean total 25(OH)D [non-Hispanic blacks (NHBs), Hispanics, and non-Hispanic whites (NHWs): 46.6, 57.2, and 75.2 nmol/L, respectively] and in the prevalence of total 25(OH)D <30 nmol/L overall (24% of NHBs, 6.4% of Hispanics, and 2.3% of NHWs) as well as stratified by season (winter months: 30% of NHBs, 7.5% of Hispanics, and 3.8% of NHWs; summer months: 17% of NHBs, 4.4% of Hispanics, and 1.6% of NHWs). Persons with higher vitamin D intakes (diet, supplements, or both) and those examined during May-October had significantly higher total 25(OH)D. Significant race-ethnicity interactions in a multiple linear regression model confirmed the necessity of providing race-ethnicity-specific estimates of total 25(OH)D.
  
  
  
  Race-ethnicity differences in the prevalence of low total 25(OH)D remained strong even after adjustment for season to account for the NHANES design imbalance between season, latitude, and race-ethnicity. The strong correlation between C3-epi-25(OH)D3 and 25(OH)D3 may be because the epimer is a metabolite of 25(OH)D3. The presence of 25(OH)D2 mainly in older persons is likely a result of high-dose prescription vitamin D2.
authors.affiliation: National Center for Environmental Health, CDC, Atlanta, GA;
authors.forename: Rosemary L
authors.initials: RL
authors.lastname: Schleicher
authors.affiliation: National Center for Environmental Health, CDC, Atlanta, GA;
authors.forename: Maya R
authors.initials: MR
authors.lastname: Sternberg
authors.affiliation: National Center for Health Statistics, CDC, Hyattsville, MD;
authors.forename: Anne C
authors.initials: AC
authors.lastname: Looker
authors.affiliation: Office of Dietary Supplements, NIH, Bethesda, MD; and.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Yetley
authors.affiliation: National Center for Health Statistics, CDC, Hyattsville, MD;
authors.forename: David A
authors.initials: DA
authors.lastname: Lacher
authors.affiliation: Office of Dietary Supplements, NIH, Bethesda, MD; and.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Sempos
authors.affiliation: Office of Dietary Supplements, NIH, Bethesda, MD; and.
authors.forename: Christine L
authors.initials: CL
authors.lastname: Taylor
authors.affiliation: Department of Preventive Medicine and Epidemiology, Loyola University, Chicago, IL.
authors.forename: Ramon A
authors.initials: RA
authors.lastname: Durazo-Arvizu
authors.affiliation: National Center for Environmental Health, CDC, Atlanta, GA;
authors.forename: Khin L
authors.initials: KL
authors.lastname: Maw
authors.affiliation: National Center for Environmental Health, CDC, Atlanta, GA;
authors.forename: Madhulika
authors.initials: M
authors.lastname: Chaudhary-Webb
authors.affiliation: National Center for Health Statistics, CDC, Hyattsville, MD;
authors.forename: Clifford L
authors.initials: CL
authors.lastname: Johnson
authors.affiliation: National Center for Environmental Health, CDC, Atlanta, GA; cpfeiffer@cdc.gov.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Pfeiffer
mesh_terms: D015652:25-Hydroxyvitamin D 2 / Q000097:blood; D000293:Adolescent; D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000368:Aged; D002112:Calcifediol / Q000097:blood; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004032:Diet; D019587:Dietary Supplements; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012621:Seasons; D053719:Tandem Mass Spectrometry / Q000379:methods; D014481:United States / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*; D014815:Vitamins / Q000097:blood; D044465:White People; D055815:Young Adult
chemical_list: D014815:Vitamins; D014807:Vitamin D; D015652:25-Hydroxyvitamin D 2; C104450:25-hydroxyvitamin D; D002112:Calcifediol
keywords: 25-hydroxyvitamin D2; 25-hydroxyvitamin D3; C3-epimer of 25-hydroxyvitamin D3; LC-MS/MS; NHANES