Randomized, double-blind, placebo-controlled, cross-over study on the antihypertensive effect of dietary integration with Grana Padano DOCG cheese

Abstract

Cow-milk fermentation induced by Lactobacillus helveticus produces peptides with sustained ACE inhibitory activity, mainly dues to 2 tripeptides (valyl-prolyl-proline and isoleucil-prolyl-proline) that have shown to lower blood pressure (BP) in experimental animals and in humans. Grana Padano DOCG, an Italian semi-fat hard cheese, has shown a potent in-vitro ACE-inhibitory effect due its high concentration of such tripeptides. In a previous randomized, open-label, controlled study, the daily dietary integration with Grana Padano cheese was accompanied by significant decrease in systolic and diastolic BP in hypertensive patient (Crippa et al, J Clin Hypertens, 2013). Present data refers to a randomized, double-blind, placebo-controlled, cross-over study in which 30 mild-moderate hypertensive individuals, presenting with BP values not on target (>140 and /or >90 mmHg) after their usual and stable (3 months at least) treatment. All patients received, in random fashion, a dietary integration with Grana Padano Cheese (30 g per day) and placebo (obtained with flavored bread mixed with fats and salts in concentrations equal to those of the cheese). BP was evaluated at baseline and at the end of the active and placebo treatment (2 months each) by: -Office BP (OBP) -Automated Office BP -Ambulatory BP (ABP) monitoring. Automated Office BP was measured by using the BpTRU, (VSM MedTech Ltd, Vancouver, Canada), an automated oscillometric device that provides multiple blood pressure measurements in an office setting in the absence of a healthcare professional. It allows 6 consecutive readings at 1 minute intervals and provides the average of the last 5 measurements. Results: Dietary integration with Grana Padano cheese resulted in a significant decrease in systolic and diastolic Office and Automated Office BP (BpTRU) mean values (Student’s t test: p< 0.05 and p < 0.025). No changes in BMI, total and HDL cholesterol, triglycerides, blood glucose, serum sodium and potassium levels were found after the dietary integration both with respect to baseline and placebo.