In 2010, the Journal of the American Medical Association reported that mammograms (which use doses of ionizing radiation) increased “the burden of low-risk cancers without significantly reducing the burden of more aggressively growing cancers, and therefore did not result in the anticipated reduction in cancer mortality.” Meanwhile a vitamin D test is a simple, safe, and inexpensive blood test that experts are deeming critical in terms of assessing risk for breast cancer.

A growing body of research is finding that women with optimal levels of vitamin D (50- 80ng/ml) significantly decrease their risk of developing breast cancer, while suboptimal levels (below 50 ng/ml) lead to a higher risk for developing the disease. Researchers from the University of Rochester Medical Center published a study in the April 2011 edition of the Annals of Surgical Oncology concluding that suboptimal vitamin D levels are “highly predictive of the presence of biological markers associated with more aggressive [breast cancer] tumors.” And a 2009 study determined that women with levels above 52 ng/ml had half the risk of developing breast cancer as those with levels at 13 ng/ml, leading researchers to estimate that 58,000 new cases of breast cancer could be prevented each year by raising vitamin D levels to 52 ng/ml.

How does vitamin D have such a powerful effect on breast health? Optimal levels of vitamin D enhance the creation and functioning of healthy cells throughout the body, encouraging cells to either grow normally or commit apoptosis (cell suicide) if they are abnormal. Vitamin D also regulates gene expression in the body, the process in which information from a gene is transformed into biochemicals the body needs to function and stay healthy. Vitamin D’s ability to stimulate the absorption of calcium may also play an important role in reducing the risk of breast cancer. Findings presented at the 2010 American Association for Cancer Research annual meeting suggested that since calcium acts to enhance DNA repair, if that biological process is disrupted it could lead to cancer– calcium can’t act without the help of vitamin D.

A woman’s vitamin D status is determined by measuring the level of 25-hydroxyvitamin D in blood serum. Current lab ranges are 30-80 ng/ml, though most functional healthcare practitioners recommend levels be at least 50 ng/ml – even higher in some cases. The two major forms of vitamin D are vitamin D2, or ergocalciferol, and vitamin D3, or cholecalciferol, which is the more biologically active form. Vitamin D3 can ultimately be obtained in three ways: from sun exposure (without sunscreen), certain foods, and supplementation.                                                                                                 

The amount of sun exposure necessary to produce 10,000 IU of D3 is about 20-30 minutes of afternoon sun for light-skinned females and a few times that for those with dark skin. What latitude a woman resides in will also impact her ability to get vitamin D from the sun; for example, those residing above around 37 degrees north won’t get enough exposure from November through early March. In addition to sunlight exposure, diseases that affect the parathyroid gland, liver, or kidney also can impair the synthesis of the active form of vitamin D.

Small amounts of vitamin D can be obtained through the diet, though very few foods naturally contain it. Those foods that do include fatty fish, fish liver oil, and eggs. Smaller amounts are found in meat and cheese. Most dietary vitamin D comes from fortified foods, such as milk, juices, and yogurt. Four ounces of wild caught salmon provides 411 IU of vitamin D while one cup of fortified, 2% cow’s milk provides about 100 IU. Since vitamin D is fat-soluble, a diet that is extremely low in fat may lead to a vitamin D deficiency.

Because so many of us cover our bodies in sunscreen before sun exposure and our diets lack an abundance of vitamin D-rich foods, it is important to supplement to bring blood levels to optimal levels. Many medical experts recommend between 3-5,000 IU daily – in the form of D3 which is the most bioavailable – for maintaining healthy levels.

You are only as good as your options, so having another test at your disposal can only add to your arsenal of preventative measures. Finding out your vitamin D levels and then supplementing to reach an optimal level may be one of the easiest and least expensive ways to maintain the health of your breasts.

References Available Upon Request