Dear Dr. Roach: I'm a 68-year-old female who is in good health. I currently take vitamin D3. The only prescription that I'm on is rosuvastatin. It has been brought to my attention by my cousin, who is ...

Another study found that vitamin D deficiency is common in people with rheumatoid arthritis (RA), and may be linked to musculoskeletal pain. Not having enough vitamin D can: affect your immune system ...