Partial substitution of carbohydrate intake with protein intake from lean red meat lowers blood pressure in hypertensive persons

• Published in: The American journal of clinical nutrition 2006-04, Vol.83 (4), p.780-787
• Main Authors: Hodgson, Jonathan M, Burke, Valerie, Beilin, Lawrence J, Puddey, Ian B
• Format: Article
• Language: English
• Subjects: antihypertensive effect; Biological and medical sciences; Blood Glucose - metabolism; Blood pressure; Blood Pressure - drug effects; Blood Pressure - physiology; Body Weight - drug effects; Carbohydrates; cardiovascular diseases; Cardiovascular Diseases - blood; diastolic blood pressure; Diet; dietary carbohydrate; Dietary Carbohydrates - administration & dosage; Dietary Carbohydrates - metabolism; dietary protein; Dietary Proteins - administration & dosage; Dietary Proteins - metabolism; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Humans; Hypertension; Hypertension - diet therapy; Hypertension - metabolism; lean meat; Lipids - blood; Male; Meat; Middle Aged; nutritional intervention; patients; portal hypertension; Potassium - urine; Proteins; red meat; Sodium - urine; systolic blood pressure; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/83.4.780

BACKGROUND: Compared with carbohydrate intake, dietary intake of plant protein can lower blood pressure in humans, but the effects of animal protein intake on blood pressure have yet to be investigated. OBJECTIVE: We aimed to determine whether partial substitution of carbohydrate intake with animal protein intake from lean red meat changes blood pressure and other markers of cardiovascular disease risk in hypertensive persons. DESIGN: Hypertensive persons (n = 60) were recruited to an 8-wk parallel-design study. The participants were randomly assigned either to maintain their usual diet (control group) or to partially replace energy intake from carbohydrate-rich foods with protein from lean red meat (protein group). Measurements were performed at baseline and at the end of the intervention. RESULTS: Compared with the control group, the protein group had a significantly higher protein intake [x (95% CI) percent of energy: 5.3% (3.7%, 6.9%), P < 0.001] and a corresponding lower carbohydrate intake [-5.3% of energy (-7.9%, -2.7%), P < 0.001]. Body weight and intakes of fat, alcohol, and fiber were not significantly different between the groups. Compared with the control group, the clinic, 24-h, awake, and asleep systolic blood pressures were lower [-5.2 (-10.3, -0.1), -4.0 (-7.4, -0.6), -4.7 (-8.9, -0.5), and -4.7 (-10.3, -0.1) mm Hg, respectively, P < 0.05] and fasting plasma glucose concentrations were higher [0.33 mmol/L (0.09, 0.58 mmol/L), P = 0.008] in the protein group. These differences were independent of age, sex, and changes in weight, alcohol intake, or urinary sodium and potassium excretion. Diastolic blood pressure and heart rate, arterial compliance, blood lipids, and serum insulin were not significantly different between the groups. CONCLUSION: Within the context of other studies, these results suggest that modest substitution of carbohydrate-rich foods with protein-rich foods may lower blood pressure in hypertensive persons.