Vitamin D From Diet And Sunshine Is Associated With A Reduced Risk Of Breast Cancer

French researchers have found that a combination of vitamin D from diet or supplements and from exposure to sunlight works best to protect postmenopausal women from breast cancer. The researchers analyzed data collected over ten years from 67,721 women. They found that postmenopausal women who lived in regions with the greatest exposure to sunshine and whose diets included dietary or supplemental vitamin D had a significantly lower risk of breast cancer, compared to women with high amounts of exposure to sunlight but low consumption of vitamin D. However, the researchers found no association between dietary/supplemental vitamin D alone and reduced cancer risk. They concluded that “a threshold of vitamin D exposure from both sun and diet is required to prevent breast cancer” and that threshold is difficult to reach in the less-sunny northern latitudes.