Vitamin D is a fat-soluble vitamin that is made by the body after exposure to ultraviolet rays from the sun. Vitamin D can also be obtained by taking supplements and from eating certain foods.

What does Vitamin D do in the body?

Vitamin D helps maintain normal blood levels of calcium and phosphorous. It aids in the absorption of calcium, helping to form and maintain strong bones. Vitamin D also modulates neuromuscular, immune and other cellular functions.

What does Vitamin D testing assess?

Vitamin D tests generally assess the total volume of 25-Hydroxyvitamin D (25OHD), which is the form of Vitamin D circulating in the blood. Vitamin D tests may also provide information on the levels of Vitamin D2 and D3, which comprise total Vitamin D levels.

Why do physicians test for Vitamin D?

A physician generally will order a test to determine the level of Vitamin D in a patient’s body. A physician would typically evaluate a test result in connection with several other factors affecting a patient’s health, such as medical history, gender and age.

For more information about Vitamin D testing please watch this new video on Why It Matters and How It’s Done.

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