The most accurate way to determine how much vitamin D is in the body of a person is the 25-hydroxy vitamin D test. In the kidneys, 25-hydroxy vitamin D is turned into an active form of the vitamin.
The active form of the vitamin can be measured in the blood. Also, this form of vitamin D helps control the level of calcium and phosphate in the body. Normal limits range from 30.0-74.0 ng/ml. A lower level indicates a vitamin D deficiency and should be medically intervened.
Treatment for vitamin D deficiency involves increasing the amount of vitamin D through diet, supplements, or spending a longer period in the sun. People who have a concentration of less than 20 ng/ml of vitamin D require treatment.
The recommended daily dose of vitamin D is 600 IU for people aged 10-70 years and 800 IU for adults over 70 years of age to optimize bone health.
Sun protection inhibits vitamin D production, so discuss with your doctor about options for taking vitamin D as supplements, especially if there are other risk factors that predispose to vitamin D deficiency. Before talking to your doctor, you should know what are the risks, symptoms and causes of Vitamin D deficiency.