I'm also taking 50,000 IU of Vitamin D -- once a week with the plan to retest in 6 weeks. I had been taking 1,000 IU twice a day, then 2,000 twice a day, for around six months, and still my level was 21 at last testing. I hope the 50,000 brings it up. It's certainly easier to take one tiny pill once a week...
In the last few months I'm seeing a teeny improvement in my hair growth after just about five years of slowly but steadily balding. The only differences have been the D supplements, almost one year of .0375 Vivelle and nightly doses of niaspan, a prescription strength niacin pill. I don't know which, if any, of those changes are making some hair grow but something's definitely causing regrowth. Sadly, so far nothing to make any sort of a cosmetic difference, just enough to get me back in compulsive mode of checking my little spouting hairs each and every single time i'm in front of the bathroom mirror.
All the research and recommendations about how important Vitamin D and how many of us are really deficient is so interesting! Ricketts sounds so ancient and foreign, but there are plenty of cases in the US in recent years -- who knows what else D deficiency is responsible for (I think the link to MS is most fascinating and encouraging...)
(Of course, supplementing with the "mega" doses has to be done with monitoring and medical supervision...)