title: Decrease in vitamin D status in the Greenlandic adult population from 1987-2010.
abstract: BACKGROUND
  Low vitamin D status may be pronounced in Arctic populations due to limited sun exposure and decreasing intake of traditional food.
  
  
  OBJECTIVE
  To investigate serum 25(OH)D3 as a measure of vitamin D status among adult Inuit in Greenland, predictors of low serum 25(OH)D3 concentrations and the trend from 1987 to 2005-2010.
  
  
  METHODS
  A total of 2877 randomly selected Inuit (≥ 18 years) from the Inuit Health in Transition study were included. A sub-sample (n = 330) donated a blood sample in 1987 which allowed assessment of time trends in vitamin D status.
  
  
  RESULTS
  The geometric mean serum 25(OH)D3 (25[OH]D2 concentrations were negligible and not reported) in 2005-2010 was lowest among the 18-29 year old individuals (30.7 nmol/L; 95% CI: 29.7; 31.7) and increased with age. In all age-groups it decreased from 1987 to 2005-2010 (32%-58%). Low 25(OH)D3 concentrations (<50 nmol/L) were present in 77% of the 18-29 year old and decreased with age. A characteristic seasonal variation in 25(OH)D3 concentrations was observed (range 33.2-57.1 nmol/L, p<0.001), with the highest concentrations in August to October. Age (2.0% per year increase; CI: 1.7, 2.2), female gender (7.1%; CI: 2.0; 12.5), alcohol intake (0.2% per increase in drinks/week; 0.0; 0.4), and traditional diet (10.0% per 100 g/d increase; CI: 7.9; 12.1) were associated with increased serum 25(OH)D3, whereas smoking (-11.6%; CI: -16.2; -6.9), BMI (-0.6%; CI: -1.1; -0.2) and latitude (-0.7% per degree increase; CI: -1.3; -0.2) were associated with decreased concentrations.
  
  
  CONCLUSIONS
  We identified a remarkable decrease in vitamin D status from 1987 to 2005-2010 and a presently low vitamin D status among Inuit in Greenland. A change away from a traditional diet may well explain the observed decline. The study argues for the need of increased dietary intake of vitamin D and supplementation might be considered.
authors.affiliation: National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
authors.forename: Nina O
authors.initials: NO
authors.lastname: Nielsen
authors.affiliation: Steno Diabetes Centre, Gentofte, Denmark.
authors.forename: Marit E
authors.initials: ME
authors.lastname: Jørgensen
authors.affiliation: Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Friis
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Melbye
authors.affiliation: Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Bolette
authors.initials: B
authors.lastname: Soborg
authors.affiliation: Department of Public Health, Aarhus University, Aarhus, Denmark.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Jeppesen
authors.affiliation: Department of Clinical Biochemistry and Immunology, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Marika
authors.initials: M
authors.lastname: Lundqvist
authors.affiliation: Department of Clinical Biochemistry and Immunology, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Arieh
authors.initials: A
authors.lastname: Cohen
authors.affiliation: Department of Clinical Biochemistry and Immunology, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: David M
authors.initials: DM
authors.lastname: Hougaard
authors.affiliation: National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark; Greenland Centre for Health Research, University of Greenland, Nuuk, Greenland.
authors.forename: Peter
authors.initials: P
authors.lastname: Bjerregaard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000097:blood; D001110:Arctic Regions; D004032:Diet; D019587:Dietary Supplements; D005247:Feeding Behavior; D005260:Female; D006116:Greenland; D006801:Humans; D008297:Male; D008875:Middle Aged; D014807:Vitamin D / Q000008:administration & dosage / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood* / Q000178:diet therapy / Q000473:pathology
chemical_list: D014807:Vitamin D