eileen

Nice article...

Vitamin D plays role in fighting diseases
By Suzanne Bohan, MediaNews
Article Last Updated: 01/21/2008 09:15:37 PM PST
For decades, most people paid little attention to vitamin D - called the "sunshine vitamin," because sun rays absorbed by the skin synthesize the nutrient that regulates calcium and helps build strong bones and teeth.
But to their surprise, scientists are learning that vitamin D appears to play an underappreciated role in preventing just about every major disease, from cancer and cardiovascular disease to multiple sclerosis and Type 1 diabetes.
"There are so many things that vitamin D may do that are beneficial," said Dr. David Feldman, a professor at Stanford University's School of Medicine, who has studied the health effects of the nutrient for 25 years.
"I'm afraid if it's hyped too much, people are going to think nothing can be this good, that it works on all these diseases," Feldman said.
About a decade ago, scientists began using radioactive material to illuminate cellular details and study the role of vitamin D in the body.
Feldman said they found vitamin D receptors in the intestinal tract, where the nutrient shuttles calcium into the bloodstream, and in bones. Receptors were also found in the kidneys, indicating that the nutrient plays a pivotal role in the functioning of the tissue.
But scientists were surprised when they found receptors in other parts of the body, including the brain, heart, prostate, breast tissue and immune cells. "We started finding them in all these other places," Feldman said. "In animals, we found, to our surprise, they were everywhere. At low levels, but everywhere."
Dr. Michael Holick, a scientist at Boston University Medical Center, said Americans typically get more than 90percent of their vitamin D from the sun.
But there is growing concern about a vitamin D deficiency in the U.S., because many people stay indoors most of the day and protect themselves in clothes and sunscreen - which block vitamin D synthesis - when they are outdoors.
The problem is especially prevalent among people of color. The melanin that shades the skin and protects against sunburn also slows, by sixfold or more, the synthesis of vitamin D. Experts say a Vitamin D deficiency is widespread among black Americans and might be linked to their high rates of prostate cancer and hypertension.
Feldman is among the many vitamin D researchers who advocate taking daily vitamin D supplements.
Holick also advises people to get 10 minutes to 15 minutes of sun exposure, two to three times per week during nonwinter months, and after that, put on sunscreen. Vitamin D is stored in fat, so adequate levels built up during the sunny season can get people through the winter.

SOURCE LINK: http://origin.dailynews.com/news/ci_8039132

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under-exposure to uv rays is as dangerous as over-exposure...This is "D" life! (eileen)