title: Effect of physical activity and sun exposure on vitamin D status of Saudi children and adolescents.
abstract: BACKGROUND
  Accumulating evidence suggests an increased prevalence of vitamin D deficiency in the Middle East. In this context, we aimed to determine whether the prevalence of vitamin D deficiency is related to degree of physical activity and sun exposure among apparently healthy Saudi children and adolescents, a little studied population.
  
  
  METHODS
  A total of 331 Saudi children aged 6-17 years (153 boys and 178 girls) were included in this cross sectional study. Levels of physical activity and sun exposure were determined using a standard questionnaire. Anthropometry, serum calcium and 25-(OH) vitamin D were analyzed.
  
  
  RESULTS
  All subjects were vitamin D deficient, the majority being moderately deficient (71.6%). Age was the single most significant predictor affecting 25 (OH) Vitamin D levels, explaining 21% of the variance perceived (p = 1.68 x 10-14). Age-matched comparisons revealed that for groups having the same amount of sun exposure, those with moderate or are physically active will have higher levels of vitamin D status, though levels in across groups remained deficient.
  
  
  CONCLUSIONS
  Vitamin D deficiency is common among Saudi children and adolescents, and is influenced by both sun exposure and physical activity. Promotion of an active outdoor lifestyle among Saudi children in both homes and schools may counteract the vitamin D deficiency epidemic in this vulnerable population. Vitamin D supplementation is suggested in all groups, including those with the highest sun exposure and physical activity.
authors: Prince Mutaib Chair for Biomarkers of Osteoporosis, King Saud University, Riyadh, Kingdom of Saudi Arabia.
authors: Abdulaziz
authors: A
authors: Al-Othman
authors: Sara
authors: S
authors: Al-Musharaf
authors: Nasser M
authors: NM
authors: Al-Daghri
authors: Soundararajan
authors: S
authors: Krishnaswamy
authors: Deqa S
authors: DS
authors: Yusuf
authors: Khalid M
authors: KM
authors: Alkharfy
authors: Yousef
authors: Y
authors: Al-Saleh
authors: Omar S
authors: OS
authors: Al-Attas
authors: Majed S
authors: MS
authors: Alokail
authors: Osama
authors: O
authors: Moharram
authors: Shaun
authors: S
authors: Sabico
authors: George P
authors: GP
authors: Chrousos
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood; D002112:Calcifediol / Q000097:blood / Q000172:deficiency*; D002648:Child; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006306:Health Surveys; D006801:Humans; D016014:Linear Models; D008297:Male; D015995:Prevalence; D012529:Saudi Arabia / Q000453:epidemiology; D013472:Sunlight; D011795:Surveys and Questionnaires; D014808:Vitamin D Deficiency / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*
chemical_list: D015415:Biomarkers; D002112:Calcifediol