title: Vitamin D status in Saudi school children based on knowledge.
abstract: BACKGROUND
  The prevalence of vitamin D deficiency in the kingdom of Saudi Arabia is rising unexpectedly in every age group. Apart from several risk factors, the lack of awareness is posing a serious threat for low vitamin D levels in children as well. The aim of our study was to compare the knowledge and status of vitamin D in Saudi school children.
  
  
  METHODS
  Saudi students, 1188 boys (15.1 ± 2.2 years) and 1038 girls (15.1 ± 2.0 years), were recruited and a pre-designed questionnaire with regards to knowledge about vitamin D was administered. Blood samples were collected and serum 25hydroxyvitamin D (25(OH)D was measured.
  
  
  RESULTS
  A significantly higher percentage of boys answered correctly than girls regarding knowledge questions as sun exposure (p = 0.002, and 0.011), breastfeeding (p < 0.001) and diseases (p < 0.001). The percentage of girls was significantly higher who thought that fruits and vegetables are not rich sources of vitamin D (24.7% girls vs. 15.4% boys; p < 0.001and 29.6% girls vs. 20.9% boys p < 0.001), respectively. Boys had a higher prevalence and frequency of sun exposure than girls (p < 0.001 for both). Girls showed a significantly higher percentage of sunscreen use and full covering during sun exposure (p = 0.001 for both).Vitamin D deficiency was significantly higher in girls than boys (47.0% versus 19.4.0%; p < 0.001). Vitamin D status in boys was significantly higher than girls (p < 0.001). In girls, those who answered correctly about vitamin D related disease (p = 0.03) and sources (p = 0.015), demonstrated significantly higher vitamin D levels.
  
  
  CONCLUSIONS
  The awareness of vitamin D and sunlight in children needs to be improved by provision of trained physicians and school teachers. Creating more areas where girls can uncover freely during routine works and outdoor activities will help increase their vitamin D levels.
authors.affiliation: King Abdulaziz Medical City, College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, 11426, Saudi Arabia. alaslawi@hotmail.com.|Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. alaslawi@hotmail.com.
authors.forename: Yousef
authors.initials: Y
authors.lastname: Al-Saleh
authors.affiliation: Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. aldaghri2011@gmail.com.|Biomarkers Research Program Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia. aldaghri2011@gmail.com.
authors.forename: Nasser M
authors.initials: NM
authors.lastname: Al-Daghri
authors.affiliation: Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. nasiruddin2006@gmail.com.|Biomarkers Research Program Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia. nasiruddin2006@gmail.com.
authors.forename: Nasiruddin
authors.initials: N
authors.lastname: Khan
authors.affiliation: Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. halfawaz@ksu.edu.sa.|Department of Food Science and Nutrition, College of Food Science and Agriculture, King Saud University, Riyadh, Saudi Arabia. halfawaz@ksu.edu.sa.
authors.forename: Hanan
authors.initials: H
authors.lastname: Alfawaz
authors.affiliation: Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. alothman65@gmail.com.|College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia. alothman65@gmail.com.
authors.forename: Abdulaziz M
authors.initials: AM
authors.lastname: Al-Othman
authors.affiliation: King Abdulaziz Medical City, College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, 11426, Saudi Arabia. msa85@yahoo.co.uk.|Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. msa85@yahoo.co.uk.
authors.forename: Majed S
authors.initials: MS
authors.lastname: Alokail
authors.affiliation: Prince Mutaib Bin Abdullah Chair on Osteoporosis, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. chrousos@gmail.com.|First Department of Pediatrics, Athens University Medical School, Athens, 11527, Greece. chrousos@gmail.com.
authors.forename: George P
authors.initials: GP
authors.lastname: Chrousos
mesh_terms: D000293:Adolescent; D004032:Diet; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D015995:Prevalence; D012529:Saudi Arabia / Q000453:epidemiology; D017678:Sex Distribution; D013472:Sunlight; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*
chemical_list: D014807:Vitamin D