Hypertension, or high blood pressure, is the most commonly treated condition in primary care settings and is a major and modifiable risk factor of cardiovascular and kidney diseases [1]. The most recent evidence suggests that nearly one-third of American adults have high blood pressure and the condition is especially prevalent in older adults, with 65% of those older than 60 years being affected [2]. Lifestyle modifications such as the adoption of the Dietary Approaches to Stop Hypertension (DASH) diet have been proven effective for decreasing blood pressure in adults with high blood pressure [3, 4]. The DASH emphasizes increased consumption of fruits/vegetables, whole-grains, lowfat dairy, nuts, and poultry/fish and reduced intakes of sodium, sugar, and red meats (including pork). However, the effects of incorporating pork into the DASH diet pattern have not been previously studied. We therefore designed a DASH diet intervention study to test whether including a large amount of pork in the DASH diet had an effect on the expected improvements in blood pressure in older adults with high blood pressure. Nineteen study participants (13 women and 6 men) completed the 18-week study. On average, participants were older (61 years), obese (BMI 31.2 kg/m2), and had elevated blood pressure (130/85 mm Hg). During weeks 1-2, participants were counseled to continue following their normal eating pattern and baseline measurements of blood pressure, body composition (weight, % body fat, and waist circumference), fasting blood glucose, insulin, and lipid concentrations, and food intake were collected. Participants were then randomly assigned to consume the DASH diet with either pork (DASH-P) or chicken/fish (DASH-CF) as the major protein source for 6 weeks (weeks 3-8). Measurements of blood pressure, body composition, and fasting blood samples were repeated during weeks 7-8 to evaluate changes in these study outcomes. Participants were counseled to return to their normal pattern for a “wash-out” period (weeks 9-12) and then consumed the alternate protein source during weeks 13-18. Measurements of blood pressure, body composition, and fasting blood samples were repeated again during weeks 11-12 and 17-18. Systolic and diastolic blood pressure were assessed manually (seated and laying down) and with a 24hr blood pressure monitoring system. After DASH-CF, manual systolic and diastolic blood pressure both decreased 6 mmHg, and 24hr systolic blood pressure decreased 8 mm Hg and diastolic blood pressure decreased 5 mm Hg. After DASH-P, manual systolic blood pressure decreased 8 mm Hg and diastolic blood pressure decreased 5 mm Hg, and 24hr systolic blood pressure decreased 7mmHg and diastolic blood pressure decreased 3 mm Hg. Our statistical analyses confirmed that changes in blood pressure were significant and were not different for DASH-P vs. DASH-CF. These results indicate that substitution of lean pork for chicken and fish as the major source of protein does not influence the effectiveness of a DASH diet to improve blood pressure control in older adults with high blood pressure. For additional information contact Wayne W. Campbell, PhD, Professor, Department of Nutrition Science, Purdue University, 765-494-8236, [email protected].
Contribute to Pork Research
Discover how you can help improve the pork industry by checking out research RFPs or sharing your own ideas. If you have a research idea, we want to know! Here’s your chance to make a difference.