I was just diagnosed with low Vitamin D. I originally went to the doctor because of severe leg, feet, and hand cramps. He did blood work, and it turns out my level is 5.9. I am now on 50,000 iu per week and 2000 iu per day. I just started this week, but I honestly feel worse instead of better. My muscle cramps are much worse. Of course, I know it's early in the treatment, but I too, would like to know how long before I start feeling better. I work full time, and I am so exhausted, I can hardly function.