【英文原文】
Sunshine & Cancer
Although too much exposure to the sun’s ultraviolet rays can cause skin cancer,sunshine may have a protective effect against some cancers,U.S.scientists said in April.They suspect vitamin D,the so-called sunshine vitamin that is also found in fortified milk and dairy products,cod liver oil and some fatty fish,can help to slow down the speed at which cancer cells divide.“This study found inverse associations between both residential and occupational exposure to sunlight and mortality from female breast and colon cancers,”said Dr.Michael Freedman of the National Cancer Institute.
In research reported in Occupational and Environ-mental Medicine,Freedman and his team studied deaths from breast,ovarian,colon,prostate and skin cancers in 24U.S.states between 1984and 1995to determine the impact of sunlight on t he diseases.Not surprisingly they found more deaths from skin cancer in sunnier states but the number of people who died from the other cancers was lower in the sunshine areas.Working outdoors in a sunny climate was also associated with fewer breast and colon cancer deaths but not with the other cancers.Freed man said more research is needed to explain the association between sunlight and certain cancers.