Vitamin D Description
Vitamin D -
Vitamin D is a fat-soluble
vitamin. Vitamin D is found in food, but also can be made in your
body after exposure to ultraviolet rays from the sun. Vitamin D
exists in several forms, each with a different activity. Some forms
are relatively inactive in the body, and have limited ability to
function as a vitamin. The liver and kidney help convert vitamin D
to its active hormone form. The major biologic function of vitamin D
is to maintain normal blood levels of calcium and phosphorus.
Vitamin D aids in the absorption of calcium, helping to form and
maintain strong bones. It promotes bone mineralization in concert
with a number of other vitamins, minerals, and hormones. Without
vitamin D, bones can become thin, brittle, soft, or misshapen.
Vitamin D prevents rickets in children and osteomalacia in adults,
which are skeletal diseases that result in defects that weaken
bones. Fortified foods are the major dietary sources of Vitamin D.
One cup of Vitamin D fortified milk supplies about one-fourth of the
estimated daily need for this vitamin for adults. Although milk is
fortified with vitamin D, dairy products made from milk, such as
cheese, yogurt, and ice cream are generally not fortified with
vitamin D. Only a few foods naturally contain significant amounts of
vitamin D, including fatty fish and fish oils.
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