I just had to share. This is a fantastic article that came out in Sept. 2008 on Vitamin D deficiency and how to treat it. Two things stood out to me. First, the vitamin D dosage and its therapeutic effect is dependent on your weight. Second, taking 1,000 IU a day over 3-4 months will usually get your number up by 10 ng/ml. Thus, if you had an initial level of 10 you would have to take 3,000 IU a day for several months to get to the level of 40. (but it's not linear)
Anyhow, there is lots of other good stuff in here.
http://www.vitamindcouncil.org/PDFs/...deficiency.pdf