I have been suffering from muscle stiffness and knee joint pains for last 3 years and the doctors said it is because of deficiency of vitamin d, also it takes time to go in gears after rising from the bed especially feeling lazy but once I am on my toes no problems. I am taking vitamin d tablets once in a week for the last 2 and half years, but no improvement. Can you please suggest me any remedy to eradicate this from the root with no side effects of the treatment. Also I am taking vitamin a, c.