Hi Marriane, My doctor, Dr. Ben Thrower, is the director of the MS Center at Sheperd Center here in GA and he has been doing a lot of research on the effects of Vitamin D and MS.....if you can, try to pull up some articles on it.....within the last year they started checking my level and the first time it was checked it came back as 9.7 which apparently is way below normal....so he put me on a very high prescription dose of Vitamin D....he said the over the counter vitamin D is too synthetic or something like that .....I am on 100,000 units once per week.....the pharmacist even questioned the dosage but when I told him my level he totally understood....it has since come up a bit , but he still has me on the same dosage.....apparently the best way to get vitamin d is from the sun....but I cannot stay out in the sun long at all.... so , do some research and you will see that there are plenty of studies going on about vitamin D and MS......and my doctor is doing extensive studies on this....   Karen Atlanta, GA