Vitamin D

Vitamin D is essential to maintain normal amounts of calcium and phosphorus in blood.  A major function is to facilitate the absorption of calcium, indirectly helping form and maintain strong bones and preventing osteoporosis in the long run.

Vitamin D is a fat-soluble vitamin not naturally found in many foods.  Fish is a great source to obtain the vitamins. Cheese and egg yolks also contain some vitamin D, but in small amounts.  Although it is not naturally found in a plethora of items, many food companies enhance their products with the vitamin.  For example, during the 1930’s the United States was having a problem with a high population getting rickets so they implemented a milk fortification program.  Doing so essentially eliminated the problem.  Since then, some brands of orange juice, cereal, and yogurt have also added the vitamin to their products.

Interestingly enough, vitamin D is also able to be absorbed through the sun’s rays and is a significant source of how people acquire the recommended amount.  Therefore, it has been nicknamed the Sunshine Vitamin.  Ultraviolet B (UVB) rays come through the clouds and are absorbed by the skin and converted into vitamin D.   The suggested amount of sunlight exposure varies slightly from each source; however, it is thought that as little as ten minutes a day is ample to prevent vitamin D deficiencies.  The time of day, amount of cloud coverage, sunscreen, and season can all affect the amount absorbed.  People living above the 42 degree north latitude line, which crosses from Boston to the northern border of California, will not be able to absorb the recommended amount from November until February.  During this time it is important for those individuals to make sure they get the adequate amount from their diets.

If you take a multivitamin it is most likely you get anywhere from 50 – 1,000 International Units (IU).  The Adequate Intake level established by the U.S. Institute of Medicine of the National Academy...