Key milk nutrients, calcium and vitamin D, may do more than just help keep your bones strong. Increasing intake of calcium and vitamin D could reduce the risk for cancer in women by at least 60 percent, according to a new study published in the American Journal of Clinical Nutrition. (1)

The four-year clinical trial included more than one thousand women over the age of 55 in one of three supplement groups:
1) calcium (1400-1500mg) plus vitamin D (1100 IU vitamin D)
2) calcium only (1400-1500 mg) or
3) a placebo.

The researchers found that the risk of developing cancer was 60 percent lower for those who took calcium and vitamin D and 47 percent lower for those taking calcium alone, compared to the placebo.

Fifty women developed nonskin cancer through the course of the four-year study, including breast, colon, lung and other cancers. When researchers excluded the 13 cancers diagnosed during first year of the study, determining these cancers were likely present at the study onset, the protective effect of calcium and vitamin D was even greater, with a 77 percent lower risk for cancer for those taking calcium plus vitamin D compared to the placebo.

With an estimated 10.5 million Americans living with cancer, researchers on a quest for new means to prevent or delay the occurrence of this deadly disease are encouraged by these findings.

“This is the first clinical trial to show that boosting vitamin D status can affect the overall risk for cancer – a proposition that has tremendous public health potential,” said lead author Dr Joan Lappe, a nutrition researcher from Creighton University in Omaha. “By choosing vitamin-D rich foods like milk and taking a supplement Americans can help improve their vitamin D levels and potentially impact their cancer risk.”

Milk is the primary source of calcium and an excellent source of vitamin D in the American diet. In fact, government reports indicate that more than 70 percent of the calcium in our nation’s food supply comes from milk and milk products. (2), (3), (4), (5) Additionally, milk is one of the few food sources of vitamin D, which is fast emerging as a “super nutrient.”

Several recent studies have reported similar conclusions, suggesting that calcium and vitamin D may reduce the risk for breast cancer in premenopausal women and colon cancer in older women. (6), (7)Together, these findings give Americans even more reason to meet the recommended three servings of lowfat or fat-free milk each day, providing 900 mg of calcium and 300 IU of vitamin D daily.

1) Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. American Journal of Clinical Nutrition. 2007;85:1586-1591.

2) Gerrior S, Bente L, Hiza, H. (2004). Nutrient Content of the U.S. Food Supply, 1909-2000. (Home Economics Research Report No. 56). U.S. Department of Agriculture, Center for Nutrition Policy and Promotion.

3) Dietary Guidelines for Americans 2005, U.S. Department of Agriculture, www.healtheirus.gov/dietaryguidelines.

4) Cotton PA, Subar AF, Friday JE, Cook A. Dietary sources of nutrients among US adults, 1994 to 1996. Journal of the American Dietetic Association. 2004; 104:921-930.

5) Weinberg L, Berner LA, Groves JE. Nutrient contributions of dairy foods in the United States, Continuing Survey of Food Intakes by Individuals, 1994-1996, 1998. Journal of the American Dietetic Association. 2004; 104:895-902.

6) Lin J, Manson JE, Lee I, Cook NR, Buring JE, Zhang SM. Intakes of Calcium and Vitamin D and Breast Cancer Risk in Women. Archives of Internal Medicine. 2007;167:1050-1059.

7) Feskanich D, Ma J, Fuchs CS, Kirkner GJ, Hankinson SE, Hollis BW, Giovannucci EL. Plasma vitamin D metabolites and risk of colorectal cancer in women. Cancer Epidemiology Biomarkers and Prevention. 2004;13:1502-1508.