A vitamin D deficiency is linked with all sorts of health problems.
I was on carbamazepine medicine for 20 years to help control my epileptic seizures. It is believed that carbamazepine can destroy Vitamin D over time. I now have moderate to severe arthritis. Carbamazepine has been around since mid 1970's, and I'm surprised my vitamin D level was not routinely analyzed since I started taking the drug in 1997.