The Great Sun Debate

Who knew sunshine could be so controversial? On the one hand, there are health experts who claim a large percentage of Americans are suffering from a vitamin D deficiency caused, in part, by this country’s overuse of sunscreen. (Other explanations include cloudy climates and lack of outdoor activities.) They argue that to get enough vitamin D, which is critical for proper muscle and both health, people need time in the sun, preferably short periods without protection. Then there are experts like those at the American Academy of Dermatology (AAD) who claim that unprotected exposure to the sun’s rays is a potential health hazard. Who is right? That remains to be seen, as researchers continue to untangle the issues associated with both sides.

“An estimated 30 to 60 percent of adults are vitamin D-deficient,” says Michael Holick, Ph.D., M.D., author of The UV Advantage and Professor of Medicine, Physiology and Biophysics, Director of the General Clinical Research Center, and Director of the Bone Health Care Clinic at Boston University Medical Center. Many experts say adults should get 1,000 International Units (IU) of vitamin D per day, which is difficult to obtain through food. Therefore, Holick says that people can supplement this daily requirement by exposing themselves to natural sunlight. He advocates that those with average skin tones spend five to 10 minutes in the sun, two to three times per week from the spring to fall, without sunscreen. (People with lighter skin should spend less time, and people with darker skin should spend more time.) Holick’s beliefs are backed by a number of recent studies that suggest vitamin D can lower the risk of diabetes as well as cancers of the breast, colon, ovaries, and prostate.

On the other side of the debate are experts such the AAD and Barbara Gilchrest, M.D., Professor and Chair of the Department of Dermatology at the Boston University School of Medicine and Boston Medical Center (BMC). They maintain that if people make a conscious effort, they can get enough vitamin D from foods, such as salmon, fortified milk and supplements, and that the harmful effects of sunlight outweigh the benefit of vitamin D production. "Any individual or organization that advocates intentional sun exposure as the preferred means of producing vitamin D is doing a tremendous disservice to the public," said Dr. Gilchrest in a prepared statement issued by the AAD. "Ultraviolet (UV) radiation is a known carcinogen that is responsible for photo aging and for well over 1 million cases of skin cancer every year in the United States.”

For more information about this ongoing debate, visit www.aad.org/public or www.uvadvantage.org. or or talk to your doctor.