Sun May Lower Risk of Endometrial Cancer

More evidence for Vitamin D's role in cancer prevention.

NYT November 27, 2007

Women in the sunniest countries seem to get endometrial cancer less often than those who live far from the equator.

Using a large World Health Organization database, researchers have found lower rates of the cancer, which strikes the lining of the uterus, in populations with a higher exposure to UVB radiation, the ultraviolet light that causes the skin to produce vitamin D.

“There is a mathematical relationship,” said Cedric F. Garland, a professor of family and preventive medicine at the University of California, San Diego, and a co-author of the study, which appears in the November issue of Preventive Medicine.

The researchers assembled information on endometrial cancer in 107 countries. In both Northern and Southern Hemispheres, the higher the latitude, the higher the risk — even after adjusting for many variables. They also found that higher rates of meat eating, per capita health expenditure and the percentage of the population that was overweight were each associated with a higher risk of endometrial cancer.

Though the researchers did not measure vitamin D levels, Dr. Garland said, “we believe that vitamin D accounts for the finding, since the geographic distribution corresponds to that of other cancers which have been shown in studies of individuals to be related to levels of vitamin D.”