Higher Nonfat Dairy Intake Can Lower Blood Pressure

Middle-aged and older women can keep their blood pressure in check through regular consumption of nonfat dairy products, especially skim milk and yogurt, according to researchers from Brigham and Womens Hospital, and Harvard School of Public Health, Boston.

Until now, population studies on the inverse association between dairy product consumption and the incidence of hypertension had been limited to children, young adults, and adults in Mediterranean countries. For this study, Dietary Intake of Dairy Products, Calcium, and Vitamin D and the Risk of Hypertension in Middle-Aged and Older Women, the Harvard researchers examined the prospective associations between intake of dairy products, from both high-fat and low-fat food sources, as well as the major nutrient components in dairy products, calcium and vitamin D, with the risk of hypertension in more than 28,000 U.S. women ages 45 and older. Intake of dairy products, calcium and vitamin D at baseline were assessed from semiquantitative food-frequency questionnaires. During the 10 years of annual follow-up, 8,710 cases of hypertension were identified.

Women with the highest average intakes of low-fat dairy (between 2.0 and 9.6 servings per day) were 11% less likely to develop hypertension, compared to women with the lowest average intake (less than 0.27 servings per day). In addition, reductions in the risk of hypertension were reported for both dietary calcium (13% decrease) and dietary vitamin D (5% decrease). No benefits were found when the researchers considered supplemental calcium and vitamin D. In addition, high-fat dairy products were not associated with any changes in the risk of hypertension.

Women who consumed more low-fat dairy products were older, less likely to smoke and drink alcohol, more likely to be physically active, use multivitamins, and had a higher prevalence of diabetes and hypercholesterolemia. Low-fat dairy intake was also positively associated with intake of fruit and vegetables, whole-grains, and energy-adjusted potassium, fiber, calcium and vitamin D intake, while inversely associated with red meat intake and cholesterol intake. Women who consumed more high-fat dairy products had generally less favorable lifestyle and diet profile.