Vitamin D, Calcium May Cut Cancer Risk

June 8, 2007 — -- I'll never forget my mother's health advice to us as children: Drink your milk, eat your greens and get plenty of fresh air and sunshine.

When it comes to cancer prevention, it turns out mom was right.

Two new studies have uncovered exciting evidence of exceptionally strong cancer-protective effects of calcium and vitamin D from food or supplement sources.

The first study was published last week in the journal Archives of Internal Medicine by Dr. Jennifer Lin and colleagues from Harvard. They report that premenopausal women with high levels of vitamin D and calcium in their diets have a lower risk of breast cancer compared to women with lower intakes of these nutrients.

The second study, published in today's issue of the American Journal of Clinical Nutrition by Dr. Joan M Lappe and colleagues at Creighton University, goes even further: Dietary supplementation of these nutrients reduces the risk of multiple types of cancer.

Together, these studies provide robust evidence of the beneficial effects that calcium and vitamin D can have on cancer prevention.

Research over the past half-century has pointed to a relationship between calcium, vitamin D and reduction of cancer risk, although the results have not been definitive.

In the 1950s, for example, scientists examined weather data and health statistics to show that areas of the country with the highest amount of sunshine, which stimulates the body to make vitamin D, had the lowest rates of colon cancer death.

Since that time, studies in both humans and animals have pointed toward cancer-preventive effects of both vitamin D and calcium, mainly for breast and colon cancers, but for other cancers as well, ranging from prostate cancer to non-Hodgkin's lymphoma.

Lin and her Harvard colleagues focused on these nutrients' effects on breast cancer by analyzing data from the Women's Health Study, funded by the National Institutes of Health.