Researchers Ponder Possible Benefits of Sunshine Vitamin
By Thomas H. Maugh II
June 10, 2008
LOS ANGELES TIMES -- Medical researchers are homing in on a new wonder drug that can significantly reduce the risk of heart disease, cancer, diabetes and many other diseases — sunshine. A study to be released today found that men who are deficient in the so-called ‘sunshine vitamin,’ vitamin D, have more than double the normal risk of suffering a heart attack. Another study last week found that low levels of vitamin D increase the risk of diabetes, and a study last month linked deficiencies to an increased risk of dying from breast cancer.
The new findings join a growing body of evidence indicating that an adequate level of the vitamin, which most people can get from 20 daily minutes in the sun, is crucial to maintaining good health. Not every scientist agrees, and there is controversy about what should be considered an adequate level of vitamin D in the blood. But sentiment gradually is shifting toward a higher intake. "We don't have a cause-and-effect relationship here yet, "said biochemist Hector DeLuca of the University of Wisconsin, to prove that higher doses of vitamin D prevent these diseases.
DeLuca was the first to demonstrate how the vitamin interacts with the endocrine system, which manages the body's hormonal balance. But the links are so suggestive "that we have to pay attention to keeping blood levels up where they will protect," he said. Until the protective effect is proved, he added, "What's wrong with keeping an adequate level of vitamin D in the blood in case it is?"
Until recently, vitamin D was viewed primarily as a protective agent against diseases of the bone, such as rickets, osteomalacia and osteoporosis. Recommendations for the vitamin are based on preventing these disorders and call for a relatively small intake — a minimum of 400 international units (IU’s) per day and perhaps twice that for elderly people, who don't get outdoors much.
The vitamin is produced from natural precursors in the body by exposing skin to ultraviolet B in sunlight. Caucasian sunbathers can get 20,000 IU’s in 20 minutes at noon in summer. But any additional exposure simply damages skin. Darker-skinned people need three to five times the exposure to produce the same amount. Sunblock interferes with production by screening out ultraviolet light.
