ECTS2013 Poster Presentations Calciotropic and phosphotropic hormones and mineral metabolism (33 abstracts)
1King Abdulaziz Medical City, National Guard, Riyadh, Saudi Arabia; 2King Fahad Medical City, Riyadh, Saudi Arabia; 3King Abdulaziz Medical, Jeddah, Saudi Arabia; 4Boston University Medical Center, Boston, Massachusetts, USA.
Low levels of 25-hydroxyvitamin D have been documented among inhabitants of the wider Middle East and North African countries. Sunlight has long been recognized as a major provider of vitamin D. In this study we aimed to determine the optimum time for sun exposure in the Central region of Riyadh, Saudi Arabia. Ampoules containing 7-dehydrocholesterol in ethanol were exposed to sunlight every hour starting from sunrise until sunset in July and December. Our results demonstrated that the time of the day has a major influence in vitamin D production. In this study, summer conversion of previtamin D3 was observed to be elevated between 0900 and 1500 h with peak hours between 1000 and 1200 h. During wintertime however, the conversion begins later at around 0930 h until 1400 h, with peak hour around 1100 h. In conclusion, the optimum time to get sun exposure for vitamin D production in Riyadh, during summer time is from 0830 h and before 1030 h, as well as after 14 h until 16 h while during wintertime its from 1000 h to 1400 h. These timings are important on a public health perspective, as its free, safe and enjoyable. Furthermore its a highly efficacious way for management and prevention of vitamin D deficiency.