To Your Health
May, 2014 (Vol. 08, Issue 05)
Surviving Breast Cancer: The Power of Vitamin D
By James P. Meschino, DC, MS
Many doctors and researchers are convinced vitamin D plays an important role in preventing various cancers, including breast cancer. Over the past 20-25 years, various studies suggest women with higher blood levels of vitamin D have an associated lower incidence of breast cancer.
In recent years (2007), a large four-year clinical trial involving 1,179 healthy, postmenopausal women over the age of 55 reported that participants supplemented with vitamin D (1,100 IU per day) and calcium (1,400-1,500 mg per day) showed a 77 percent reduction in incidence of all combined invasive cancers, including breast cancer, compared to women given placebo only.
But what about women who have already experienced breast cancer? Can vitamin D supplementation help prevent breast cancer recurrence, progression and related fatality? A study published in March 2014 in Anticancer Research has now shown that breast cancer survivors would be well-advised to keep their vitamin D blood level within the ideal range. The study showed that breast cancer patients with high levels of vitamin D in their blood were twice as likely to survive the disease compared to women with low levels of vitamin D.
These researchers analyzed data from five large breast cancer studies involving a total of 4,443 breast cancer patients, with an average follow-up period of nine years. The data showed that women with an average vitamin D blood level of 30 ng/ml experienced survival rates double that of women with an average vitamin D blood level of only 17 ng/ml. The researchers pointed out that the average vitamin D blood level in patients with breast cancer in the United States is 17 ng/ml.
Vitamin D has been shown to reduce cancer development and progression in a number of ways: 1) It slows down the rate of cell division, which reduces the likelihood that cancerous mutations will emerge. 2) It promotes maturation (differentiation) of newly formed cells, which reduces transformation to a cancerous state. 3) It favorably modulates the function of immune cells, many of which are responsible for identifying and destroying emerging cancer cells.
In addition, vitamin D is responsible for increasing the cell's production of a surface receptor (antennae) known as "E-cadherin," which enables the cell to bind to and communicate with adjacent cells or supporting tissues. Very aggressive cancer cells tend to have low levels of E-cadherin, which enables them to replicate unchecked by adjacent cells. This gives cancer cells the green light to invade adjacent tissues and spread into the blood and lymphatic system in their quest to metastasize throughout the body.
Vitamin D toxicity is not known to occur until reaching a vitamin D blood level at or above 100 ng/ml, so there is a large margin of safety when taking vitamin D supplements. However, talk to your doctor about checking your blood levels of vitamin D before substantially increasing intake.
James Meschino, DC, MS, practices in Toronto, Ontario, Canada and is the author of four nutrition books, including The Meschino Optimal Living Program and Break the Weight Loss Barrier.