Vitamin D and breast cancer




Cancer Research

Related Monographs

Consumer Data: Vitamin D Breast Cancer
Professional Data: Vitamin D Breast Cancer


The incidence of breast cancer has been increasing steadily for decades. In 1972 when President Nixon declared our national war on cancer, a woman’s lifetime risk of developing breast cancer was 1 in 20. Today breast cancer rates have escalated to the point where women’s lifetime risk of developing breast cancer is 1 in 8. In the year 2000, the American Cancer Society estimates that nearly 182,800 women will be diagnosed with breast cancer and approximately 40,800 women will die from it. This means that every three minutes a woman in the United States is diagnosed with breast cancer and every twelve minutes, a woman dies from this dreaded disease. Breast cancer has become the second largest cause of cancer death in women, after skin cancer, and the leading cause of death for women between the ages of 35 and 54. Consequently, some physicians and research scientists are now referring to this as the breast cancer epidemic.

An article published in the February 2001 issue of the journal, Cancer Research, evaluated the role that vitamin D plays in breast cancer cells. Vitamin D is a fat-soluble vitamin that is converted in the kidneys to the hormone calcitrol, which is actually the most active form of vitamin D. The effects of this hormone are targeted at the intestines and bones. The authors of this particular study conducted in Israel set out to determine if vitamin D works as a pro-oxidant in breast cancer cells. The mechanism by which vitamin D affects breast cancer cells is a complex maze of enzyme reactions. The results of this study indicated to the authors that vitamin D does in fact act as a pro-oxidant in breast cancer cells. They state that vitamin D, "causes an increase in the overall cellular redox potential that could translate into modulation of redox-sensitive enzymes and transcription factors that regulate cell cycle progression, differentiation, and apoptosis", or cell death.1


1. Koren R, et al. Vitamin D is a prooxidant in breast cancer cells. Cancer Res 2001 Feb 15;61(4):1439-44.