Vitamin D Deficiency Makes Breast Cancer More Deadly

Vitamin D Deficiency Makes Breast Cancer More Deadly
Women with low levels of vitamin D when they’re diagnosed with breast cancer are more likely to die from the disease than those who have higher levels of the vitamin, doctors are reporting.

The finding — part of a growing body of evidence that connects vitamin D to several types of cancer — was just published, ahead of the upcoming American Society of Clinical Oncology conference. It was based on a University of Toronto study of 512 women diagnosed with breast cancer between 1989 and 1995. Researchers kept track of the women’s health through 2006.

Vitamin D levels were broken into three categories: “deficient” (192 of the women were in this group) “insufficient” (197 women) and “sufficient” (124 women). (Even among healthy women, high rates of vitamin D deficiency are common.)

Those with deficient levels were 73% more likely to die than those with sufficient levels. Cancer was also significantly more likely to spread to other parts of the body in women with vitamin D deficiency, the researchers found.

Previous studies have connected low vitamin D levels with higher risk of colon, prostate and breast cancer, as well as higher mortality from the cancers, according to this NEJM article.