The effects of dairy consumption on metabolic risk factors for ischemic heart disease

Purpose. The aim of this study was to determine whether consuming 3 or more servings of dairy foods daily for 24 weeks resulted in a more favorable metabolic profile compared to consuming less than one serving of dairy daily, following an initial weight loss of 10% original body weight.; Design. The study was a randomized clinical trial.; Methods. Seventy-six participants (38 men and 38 women) were recruited for the study. Participants were healthy, obese (BMI 30-40), and age 18-55. All participants took part in a 36 week weight maintenance study. During the first 12 weeks, participants took part in a 1200 kcal weight loss diet, designed to achieve a minimum of ten percent weight loss. This weight loss diet was followed by 24 weeks of weight maintenance, during which time participants consumed either a high (>3 servings per day) or low (<1 servings per day) dairy diet. Self-reported minutes of physical activity, fruits and vegetables, and dairy consumption were reported weekly. Weight, waist circumference, blood (HDL-cholesterol, triglycerides, and glucose), and blood pressure were assessed every 12 weeks.; Results. Participants in the high dairy condition consumed more dairy (p<0.05), but consumed a similar number of fruits and vegetables compared to the low dairy condition. Physical activity was also similar between the two conditions. Participants in the high dairy condition consumed 1377+/-342 mg·day-1 of calcium, while participants in the low dairy condition consumed 620+/-106 mg·day-1 (p<0.05). There was no difference between conditions at any time point for body weight, waist circumference, HDL-cholesterol, plasma triglycerides, plasma glucose, or blood pressure (both diastolic and systolic). The prevalence of metabolic syndrome was reduced 66% in the study participants. Dairy consumption did not alter the reduction in metabolic syndrome.; Discussion. The data from the present study do not support the proposed relationship between dairy consumption and reduced metabolic risk for ischemic heart disease. Components of the metabolic syndrome were not reduced as a result of 24 weeks of 3 or more servings of dairy daily when compared to consuming 1 or fewer servings of dairy.