LINK STUDIED — The vitamin D in milk and certain foods and that are produced from exposure to sunlight may play a role in reducing breast cancer risk.
Vitamin D and breast cancer link
Try as they may, the thousands upon thousands of medical researchers, scientists and doctors around the world have not yet figured out a way to eradicate cancer. Ongoing studies examining the disease as well as its risk factors may not have yielded a cure, but they certainly have helped shape a number of different methods of reducing risk and improving treatments.
Breast cancer is a prolific disease affecting a quarter of a million women in the United States each year, annually claiming the lives of roughly 40,000 women. The Canadian Cancer Society says breast cancer accounted for 13.9 percent of the 36,100 female cancer deaths in 2013. Breast cancer remains the second most common cause of cancer deaths in women, and females are continually on the lookout for ways to reduce their risk of developing this potentially deadly disease.
Vitamin D may help reduce breast cancer risk, and it may even help women already diagnosed in their fight against the disease. According to a meta-analysis of five studies published in the March 2014 issue of Anticancer Research, patients diagnosed with breast cancer who had high vitamin D levels were twice as likely to survive when compared with those who had low levels of vitamin D. This analysis studied more than 4,500 breast cancer patients over a nine-year period.
The study’s authors also found that a vitamin D level of 50 ng/ml is associated with a 50 percent lower risk for breast cancer. In addition, a study published in the American Journal of Preventative Medicine in 2007 found that a higher level of vitamin D is associated with a 50 percent lower risk of colorectal cancer.
Vitamin D is most often credited with helping the body maintain its balance of calcium and phosphorous by controlling how much of these nutrients are absorbed from foods and added to bones.
Although not fully understood, vitamin D also plays a role in other areas of the body, including the nervous system, muscles and immune system. Vitamin D also affects inflammation as well as cell growth and death, which may help prevent cancer growth.
Women who are born with the BRCA1 gene mutation are at an increased risk for developing breast and ovarian cancers. BRCA1 genes are tumor suppressor genes that, when formed properly, work to prevent cells from growing into cancerous cells. When people have mutated or altered versions of these genes, cancer cells can grow unchecked. Vitamin D may play a role in turning off the pathway by which cancerous tumors grow.
Vitamin D receptors are found on the surface of cells where they receive chemical signals. By attaching themselves to a receptor, says the Vitamin D Council, these chemical signals direct a cell to divide or die. Vitamin D receptors in breast tissue can cause cells to die or stop growing and may prevent cancer cells from spreading to other parts of the body. In turn, vitamin D may be protecting the breast against cancer. However, this is a complex area of study that is not fully understood. Right now it cannot be said with certainty that vitamin D can fully prevent cancer growth.
Observational research has indicated that women with low levels of vitamin D have a greater risk for breast cancer, particularly women who are post-menopausal.
Vitamin D3 is naturally produced in the body through exposure to ultraviolet sunlight and, like vitamin D2, can be absorbed from food. Vitamin D can be found in fish oils, liver, cheese, egg yolks and supplemented dairy products.