Does vitamin D fight breast cancer?

Vitamin D's role in breast cancer prevention is still up for debate. There's some evidence that vitamin D does protect against the disease, but a 2008 National Women's Health Initiative study of more than 36,000 menopausal women found that those who took 400 international units (IUs) of vitamin D per day were no more protected from breast cancer than those who swallowed a placebo (a sugar pill containing no active ingredients). Plus, the Institute of Medicine recently said there's no evidence to show that vitamin D helps prevent breast cancer. Even so, some experts argue that more research needs to be done to see if higher doses of vitamin D might be useful in fighting breast cancer.
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
A study shows that vitamin D interacts with some genes associated with breast cancer. Cells need to be turned on to fight breast cancer; vitamin D can penetrate cells and turn on the genetic code to fight cancer.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.