The Vitamin D Debate.

Byline: --LINDSY VAN GELDER

With all the talk about the evils of sun exposure, it's easy to forget that sun may be beneficial to your health. Ultraviolet rays contribute to aging and wrinkling, but they also help the body generate necessary vitamin D--and studies indicate that many people are not getting enough of it.

Those who live in sunny southern climates are less likely to die from diseases such as breast cancer and lung cancer than people in the north, according to Dick Setlow at the U.S. Department of Energy's Brookhaven National Laboratory and other scientists in Norway. They think that increased vitamin D production from sun exposure underlies the heightened ability to survive certain cancers. Women with the highest levels of the vitamin have a slower rate of cell aging and lower levels of C-reactive protein, a marker for unhealthy inflammation, according to The American Journal of Clinical Nutrition . But when researchers evaluated healthy people under 30, more than 60 percent of them lacked adequate vitamin D at the end of a Boston winter. Although expert opinion is mixed about the extent to which sunscreen use interferes with vitamin D production, some sun-phobic women have been shocked to ...