Prevalence of vitamin D deficiency and its associated factors in three regions of Saudi Arabia.

To measure prevalence of vitamin D deficiency in Saudi Arabia, unveil the life style, nutritional habits and status, as well as identify the potential risk factors. Method: A school-based survey targeting Saudi school students and employees was conducted during the  period from 2013 to 2014 using multistage cluster random sample in Central, Western and Eastern regions. The prevalence of vitamin D deficiency and difference between various population subgroups were calculated.