The author of this blog is a primary care internal medicine physician. Since 2005 he has ordered over 9,000 25-hydroxyvitamin D levels and treated over 7,000 patients with vitamin d insufficiency. He has follow-up of 1 to 8 years on a large percentage of these patients. The 7,000 figure is higher than most vitamin D studies.
USA TODAY ONLINE LETTER TO THE EDITOR, April, 2009 TAKING VITAMIN D. March, 2009 TWITTER WEB SITES, March, 2009 VITAMIN D IN THE NEWS, December, 2008 VITAMIN D, AN OVERVIEW, December, 2008 GETTING YOUR VITAMIN D RESULTS, December, 2008