Researchers from the University of Toronto have found for the first time that women who were vitamin D deficient at the time of their breast cancer diagnosis were 94 percent more likely to have their cancer spread, and 73 percent more likely to die from their cancer, compared with women who were not vitamin D deficient.Researchers at the University of Toronto studied the correlation between vitamin D levels in the blood, the rate of breast cancer metastases -- the incidence of having the cancer spread -- and the overall survival rates of 512 women who were diagnosed with breast cancer between 1989 and 1995. The women were followed until 2006.
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