Vitamin D protects against breast cancer
MedWire News: Vitamin D supplements, taken daily, reduce the risk of breast cancer and other tumors in postmenopausal women, results of a US study suggest.
Dr Joan Lappe and colleagues from Creighton University in Omaha, Nebraska, explain that there is a growing body of evidence indicating that high levels of vitamin D may help protect against a variety of conditions, including cancer.
To investigate, the researchers studied 1179 women aged 55 years or older from rural eastern Nebraska. The participants took 1400–1500 mg calcium supplements, calcium plus 1100 IU vitamin D3 supplements, or placebo every day for 4 years.
Over the course of the study, 50 of the participants developed cancer, including 19 breast, 3 colon, and 7 lung tumors.
Women in the calcium plus vitamin D3 group had a 60% lower incidence of cancer than those in the placebo group, and women in the calcium-only group had a 47% lower incidence.
Analysis confined to cancers that occurred after the first year of the study revealed a 77% lower risk of cancer among women taking the calcium plus vitamin D3 supplement, compared with placebo.
"The findings are very exciting. They confirm what a number of vitamin D proponents have suspected for some time but that, until now, have not been substantiated through clinical trial," said Dr Lappe.
"Vitamin D is a critical tool in fighting cancer as well as many other diseases."
The research is published in the American Journal of Clinical Nutrition.
Am J Clin Nutr 2007; 85: 1586–1591
http://www.ajcn.org/cgi/content/abstract/85/6/1586
© 2006 CMG