One of the first things many women do to lose weight is to stop eating cheese, milk and other dairy products. According to a new long−range study of women and hypertension, however, this may not be wise.

After following nearly 30,000 women for a decade, this study found strong evidence that eating low−fat dairy foods is associated with a lower risk of developing hypertension, or high blood pressure.

Interestingly, increasing consumption of calcium and vitamin D in pill form had little or no effect on blood pressure.

There was also a beneficial effect on blood pressure for women who had a high intake of calcium and vitamin D, both of which are abundant in dairy products.

Interestingly, increasing consumption of calcium and vitamin D in pill form had little or no effect on blood pressure. The authors of this study offer no theory about why this might be. However, other studies — including those on the healthful effects of dietary calcium — have found greater benefits from nutrient or vitamin−rich whole foods than from supplements containing those same vitamins and nutrients.

The bottom line is that the "complete nutrition profile" of foods is key to their health effects, says lead researcher Dr. Lu Wang, of Brigham and Women's Hospital in Boston.

The study followed 28,886 U.S. women, 45 or older. Over 10 years, 8,710 of the women developed high blood pressure, but the risk was 11 percent lower for those whose diet was high in low−fat dairy versus those who ate less low−fat dairy. Regardless of calcium content, high−fat dairy products carried no blood pressure−reducing benefit. The reason, speculates Wang's team, is that the saturated fat in whole milk compensates for any blood−pressure benefits of calcium or other nutrients.

U.S. dietary guidelines call for Americans to consume three servings of milk products per day. "Our study findings support this recommendation and emphasize the importance of low−fat dairy products," Wang said.

The study appears in the February 7, 2008 issue of the (online) medical journal Hypertension.