A vitamin D test measures your blood's vitamin D levels to see if they are too high or too low. Low vitamin D levels can ...
Vitamin D is essential for many bodily processes, particularly the development of healthy bones. A 25-hydroxy vitamin D test can reveal whether the vitamin D levels in a person’s blood are within a ...
Historically, 400 IU (10 ug) of vitamin D was recommended for better health because it closely approximated the amount of vitamin D in a teaspoonful of cod liver oil. However, 800 to 1,000 IU is the ...