These new findings about breast cancer risk and sun exposure based on skin color measurements are consistent with previous research by John and colleagues that had shown that women who reported frequent sun exposure had a lower risk of developing breast cancer than women with infrequent sun exposure.
The researchers stressed that sunlight is not the only source of vitamin D, which can be obtained from multivitamins, fatty fish and fortified foods such as milk, certain cereals and fruit juices. Women should not try to reduce their risk of breast cancer by sunbathing because of the risks of sun-induced skin cancer, they said.
If future studies continue to show reductions in breast cancer risk associated with sun exposure, increasing vitamin D intake from diet and supplements may be the safest solution to achieve adequate levels of vitamin D, said Gary Schwartz, Ph.D., a co-researcher from the Comprehensive Cancer Center at Wake Forest University School of Medicine.
Since many risk factors for breast cancer are not modifiable, our finding that a modifiable factor, vitamin D, may reduce risk is important, said Sue Ingles, Ph.D., a co-researcher from University of Southern California Keck School of Medicine.
The researchers compared 1,788 breast cancer patients in the San Francisco Bay area with a matched control group of 2,129 women who did not have breast cancer. They included non-Hispanic white, Hispanic and African-American women, thus women with a wide range of natural skin color and a wide range of capacity to produce vitamin D in the body. Skin color is an important factor that determines how
|Contact: Karen Richardson|
Wake Forest University Baptist Medical Center