Effect of Vitamin D Oral Supplements on 25 OH Vitamin D Levels
Effect of Vitamin D Oral Supplements on 25 OH Vitamin D Levels
Vitamin D deficiency is common world wide. 25 OH vitamin D level is the best indicator of
 vitamin D status. Vitamin D supplements are available as vitamin D2 or D3, in small daily or
 large weekly/monthly doses. Controversy continues on the relative potency of vitamin D2
 compared to D3 and of daily compared to weekly or monthly doses, in increasing/maintaining
 total 25 OH vitamin D level.

 The investigators plan to conduct a controlled trial to compare the effect of various vitamin
 D supplements on 25 OH vitamin D levels in healthy adults with starting 25 OH vitamin D level
 between 20 to 50 nmol/L.
Inclusion Criteria:

 -  Healthy adults living in Riyadh area who consume no more than one serving of milk/day,
 do not take vitamin supplement, habitually have less than 10 hr of sun exposure per
 week, don't suffer from granulomatous conditions, liver disease, or kidney disease,
 and don't take anticonvulsants, barbiturates, or steroids.

 -  25 OH vitamin D level between 20 to 50 nmol/L.