The New York Times has, over the years, had many articles on Vitamin D Jane Brody was the most recient: Reasons That Vitamin D May Matter She allows that 1,000 IU is good, but wants to wait for a clinical trial to finish in 2016 before recommending 2,000 IU We doubt that the 2016 clinical trial using 2,000 IU will show much benefit for the obese woman who makeup that entire trial.
35 completed random controlled clinical trials with positive results http://www.vitamindwiki.com/tiki-index.php?page_id=2303
60 overviews of vitamin D - examples: MS, how much to take, Toxicity, Obesity, seniors, http://www.vitamindwiki.com/tiki-browse_categories.php?parentId=57
700+ intervention clinical trials (take vitamin D and see what happens) http://www.vitamindwiki.com/tiki-index.php?page_id=2210
26 reasons for vitamin D deficiency - 12 of which are new in the past 40 years http://www.vitamindwiki.com/tiki-index.php?page_id=1586
Published recommendations for vitamin D around the world http://www.vitamindwiki.com/tiki-index.php?page_id=1293 - - - - - - - - - - - - - - - - - - - - - - - - - - Tried again to post a comment - this time without any URLs - in case that was the problem - It worked!!
Actually there already have been more than 35 completed random controlled clinical trials of vitamin D with positive results.
Vitamin D is looking so promising that there are >700 intervention clinical trials (take vitamin D and see what happens), far more than the total for all other supplements ever.
There are more intervention trials for vitamin D than any other medical drug, substance, or device - - - - - - - - -