Long known as a critical vitamin for bone health, other roles for vitamin D in the body are becoming evident. This fat-soluble vitamin is important in cell proliferation, growth and differentiation. It may also be important in the prevention of diabetes and diseases of chronic inflammation. As new insights emerge about the varied actions of vitamin D, it has become a subject of increasing interest to cancer researchers.
Cancer
Research on the connection between low vitamin D and elevated breast cancer risk is inconsistent. The Office of Dietary Supplements reports that there has not been strong evidence of a protective role for vitamin D in breast cancer prevention. Epidemiological studies of colon cancer suggest that vitamin D may be protective against those tumors. However, additional research is needed before vitamin D can be recommended for prevention of any type of cancer in the general population.
Other Health Benefits
Together with calcium, vitamin D is essential for the maintenance of strong bones. The University of Maryland Medical Center notes that a vitamin D supplement reduces the risk of rickets and osteomalacia, a disease of bone softening. In postmenopausal women, vitamin D plus a calcium supplement helps to maintain bone mass, decrease the incidence of fractures and prevent osteoporosis.
Sources
Vitamin D is synthesized by the body when the skin is exposed to sunlight and stored for later use. However, people in many areas of the northern hemisphere may not receive enough sunlight throughout the winter months to sustain vitamin D stores. Vitamin D is also present in fortified foods such as milk and other dairy products.
Recommendations
Research on the effectiveness and appropriate doses for vitamin D in prevention and treatment of breast cancer is still ongoing. The National Cancer Institute has not yet found sufficient evidence to recommend additional vitamin D supplementation for cancer patients or those at high risk. According to the ODS, adults should receive the recommended daily allowance of 600 International Units of vitamin D per day.
