Researchers gave 36,282 postmenopausal women, aged 50 to 79, 1,000 mg of elemental calcium plus 400 IU of vitamin D per day or a placebo. After seven years of follow-up, while there were no differences between groups overall, in a subgroup of women who had had a previous non-melanoma skin cancer, those in the calcium-vitamin D group had 57 percent fewer melanomas than the placebo group.
Discussing the results, study authors said, βIn preventive medicine, we want to target people most at risk for the disease. If you previously had a non-melanoma skin cancer, calcium plus vitamin D might reduce your risk for the more deadly melanoma.β