According to the report released by the Institute of medicine that the only thing vitamin D and calcium have been proven to help is with avoiding rickets and maintaining strong bones. Too much of everything is bad, that is the rule of the thumb.
According to Dr. Holick who was the first person to identify the major circulating form of vitamin D in human blood and to determine vitamin D is synthesized in yhe skin says that "You cannot obtain enough vitamin D to your diet. The 3 steps strategy reccomended are injest food that naturally contain or are fortified with vitamin D along with sensible sun exposure and taking vitamin d supplement. Control of vitamin D ensuring enough vitamin D to Body is reccommended."