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Nutrition Column

Vitamin D proves more important than calcium in preventing disease.

Over 50 percent of elderly and 32 to 41 percent of young adults are deficient in vitamin D - a leading cause of degenerative disease.

With much attention these days on calcium and the fortification of foods ranging from milk to orange juice to antacids, the intake of calcium as a whole has improved. Most women are aware of the Food and Nutrition Board's daily recommended intake level (RDI) for calcium of between 800 and 1200 mg, depending on one's age and health status.

Vitamin D is another story. A large amount of research has found that over half of all free living and institutionalized seniors are reported to be vitamin D deficient. And the problem is not limited to the elderly.

In a study of young girls in Maine (ages 10 to 13 years old) 20 percent and 43 percent were deficient in vitamin D at the end of the summer and winter, respectively. Another study on 18 to 29 year-old medical students found 32 percent were deficient at the end of the winter months.

So what is the result of deficient vitamin D levels? Research by vitamin D expert M.D., Ph.D. Michael Holick, as well as work performed by other groups, has linked low plasma vitamin D levels with a host of degenerative diseases including type I diabetes, cancer, heart disease, hypertension, muscle weakness, autoimmune disorders, and as expected osteoporosis.

While it was once thought that adequate exposure to sunlight, and its UVB rays, would provide enough of a stimulus for our own bodies to produce enough pro-vitamin D within the skin cells- the above studies confirm that this is not the case. In all regions of the continental United States the exposure to sunlight is not adequate in winter months to stimulate adequate production within the body. And even in the summer if too much sunscreen (as low a SPF 8)is used or not enough exposure time is met then plasma levels remain low.

The current RDI for vitamin D stands between 200 and 600 IU. In order to assure adequate blood levels of vitamin D and to prevent disease most experts are urging the government to raise the RDI to 1000 IU. Some are even recommending 2000 IU daily.

It is estimated that 1000 IU daily is needed to satisfy the bodies needs and to maintain a blood concentration of at least 20 ng/ml -with a level of 30 ng/ml preferable for maintenance of health.

The only way to determine your vitamin D status is to have your blood levels checked. Once checked, and if you are low,you and your physician can determine whether a supplement, more fortified foods, or more time in the sun (without sunscreen) is the remedy for your deficiency.

Written by Dr.Sternlicht for on 11.29.05