Vitamin D Deficiency Linked to Breast Cancer

Sometimes, the basics of nutrition can make a difference. The Breast Cancer Research Foundation's Pamela Goodwin, MD, Senior Investigator at the Samuel Lunenfeld Research Institute of Mount Sinai Hospital at the University of Toronto, has demonstrated this principle.

Her research presented at this year's American Society of Clinical Oncology Annual Meeting in Chicago, May 30-June 3 shows a correlation between low vitamin D levels and poor breast cancer prognosis. A moderate supplement, similar to that recommended for maintaining bone health, may be the key to avoiding deficiency.

Media reports on Goodwin's findings have already been published in The New York Times, The Associated Press, The Los Angeles Times and Bloomberg News.

In a study of Canadian women, Goodwin discovered that vitamin D deficiency is common among breast cancer patients and is associated with higher-grade breast cancer tumors. She also discovered that patients with vitamin D deficiency had an increased risk of recurrence and lower overall survival rates than those with sufficient vitamin D levels. Vitamin D is produced by the body in the presence of sunshine and occurs in many foods such as fatty fish, eggs and whole milk. The nutrient helps regulate cell growth and differentiation, offsetting cancer cell aggressiveness.

"Breast cancer is still the most common cancer among Canadian women," says Goodwin. "This research helps us to identify a correlation between vitamin D levels in breast cancer patients and encourages us to seek further knowledge."

The research also indicates that very high blood levels of vitamin D may increase risk of death in women with breast cancer. This preliminary observation requires further investigation.

Goodwin's study tracked 512 Toronto women with early stage breast cancer more than 12 years after their initial diagnosis, and revealed that women under age 50, those who were overweight and those who consumed few grains and cereals had the lowest vitamin D levels. The vitamin D was measured in blood samples taken during both summer and winter months.

In addition to moderate supplementation of vitamin D, Dr. Goodwin recommends that patients consider having their blood levels of vitamin D checked to ensure they are in the healthy range.

"This work adds an important new link in the chain of evidence connecting proper amount of vitamin D with overall good health," said Dr. Larry Norton, MD, Deputy Physician-in-Chief of Breast Cancer Programs at Memorial Sloan-Kettering Cancer Center and Chairman of the Executive Board of Scientific Advisors of The Breast Cancer Research Foundation.