Sunny Facts - Vitamin D And You

A study by researchers at the University of California found that solar ultraviolet B (UVB) radiation can significantly reduce the risk of 16 different types of cancer by naturally stimulating the production of vitamin D in the skin. The study's authors are Cedric F. Garland, Dr. P.H., from the Department of Family and Preventive Medicine at the University of California, San Diego, and William B. Grant, Ph.D., director of the Sunlight, Nutrition and Health Research Center (SUNARC). "Enhancing vitamin D status appears to be the single most important simple thing people can do to reduce their risk of cancer, apart from avoiding tobacco and moderation in the intake of alcohol," say Cedric Garland and William Grant. It has been frequently reported that those who work outdoors have a reduced risk of developing melanoma. The reasons appear to be twofold: • They develop a tan that blocks the penetration of ultraviolet radiation so it can't produce the free radicals that can lead to melanoma. • They produce lots of vitamin D.

The researchers recommend that people get their vitamin D from exposure to natural sunlight. Fair-skinned people who live in sunny regions of the country can produce about 1,500 IU of vitamin D in 20 minutes of exposure at noon if only 10 to 20 percent of their body is exposed -- such as chest, back and arms. People should try to expose more of their skin surface for a shorter amount of time, rather than stay in the sun longer with minimal skin exposure, the study says. Darker-skinned people may need up to four times as long to make the same amount of vitamin D as fair-skinned people. The study recommends wearing hats to avoid prolonged sun exposure on more sensitive parts of the body, such as the face, and to keep moving when in the sun. Garland and Grant caution fair-skinned people to avoid over-exposure, since the skin produces sufficient vitamin D in just 20 minutes a day. To Your Health, John Hall