title: The prevalence and determinants of use of vitamin D supplements among children in Alberta, Canada: a cross-sectional study.
abstract: BACKGROUND
  Limited cutaneous synthesis due to low sun exposure and inadequate dietary intake makes vitamin D supplementation a necessity for many Canadian children. Identification of the factors associated with supplement use is necessary for public health awareness campaigns, but they have not been identified previously. Therefore, the purpose of this study was to assess the prevalence and the determinants of the use of vitamin D supplements among children in the province of Alberta, Canada.
  
  
  METHODS
  In 2014, a representative sample of grade five students (10-11 y) in Alberta (n = 2686) was surveyed. Data on dietary intake and use of vitamin D supplements were obtained using a modified Harvard Youth/Adolescent Food Frequency questionnaire. Mixed effect multiple logistic regression was employed to identify the key correlates of supplement use.
  
  
  RESULTS
  Use of vitamin D supplements by children was 29.45 % although only 11.83 % took supplements daily. Children who resided in a metropolitan area (OR = 1.32; 95 % CI:1.06-1.65), were more physically active (2nd tertile: OR = 1.39; 95 % CI:1.09-1.78 and 3rd tertile: OR = 1.70; 95 % CI:1.33-2.16), or whose parents completed college (OR = 1.35; 95 % CI:1.05-1.74) were more likely to take vitamin D supplements. Prevalence of use was highest among those who had a high vitamin D diet and those with under/normal body weight status, although supplement use was not statistically associated with either dietary vitamin D intake or weight status.
  
  
  CONCLUSIONS
  A considerable proportion of children did not take vitamin D supplements. Region of residence, physical activity level and parental education were determinants of supplement use, independent of child's gender, household income, weight status and dietary practices. We suggest prioritizing public health efforts to support strategies to make parents aware of the importance of providing the correct dose of vitamin D supplements for their children to meet dietary recommendations.
authors.affiliation: School of Public Health, University of Alberta, Population Health Intervention Research Unit, 3-50 University Terrace, 8303 112 Street, Edmonton, AB, T6G2T4, Canada. lalani.m@ualberta.ca.
authors.forename: Lalani L
authors.initials: LL
authors.lastname: Munasinghe
authors.affiliation: Agricultural, Food & Nutritional Science, University of Alberta, 4-378 Edmonton Clinic Health Academy, 11405 87 Avenue, Edmonton, AB, T6G1C9, Canada. nwillows@ualberta.ca.
authors.forename: Noreen
authors.initials: N
authors.lastname: Willows
authors.affiliation: School of Public Health, University of Alberta, 3-299 Edmonton Clinic Health Academy, 11405 87 Avenue, Edmonton, AB, T6G1C9, Canada. yan.yuan@ualberta.ca.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: School of Public Health, University of Alberta, Population Health Intervention Research Unit, 3-50 University Terrace, 8303 112 Street, Edmonton, AB, T6G2T4, Canada. paul.veugelers@ualberta.ca.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Veugelers
mesh_terms: D000416:Alberta; D001835:Body Weight; D002648:Child; D003430:Cross-Sectional Studies; D004032:Diet; D019587:Dietary Supplements / Q000706:statistics & numerical data*; D004522:Educational Status; D015444:Exercise; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D010290:Parents; D015995:Prevalence; D011795:Surveys and Questionnaires; D014505:Urban Population; D014807:Vitamin D / Q000008:administration & dosage*; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D014815:Vitamins; D014807:Vitamin D