RANDOMIZED STUDY OF THE EFFECTS OF COCOA-RICH CHOCOLATE ON THE VASCULAR FUNCTION AND THE VENTRICLE-ARTERIAL COUPLING OF YOUNG AND HEALTHY ADULTS

Abstract

Objective: The purpose of this study was to evaluate and explore the benefits of long-term dark chocolate intake in young healthy adults by measuring cardiovascular function. Design and method: A randomized study was conducted in 30 healthy participants aged 18 to 27 years. Half of the participants ingested a 20 g dose of low cocoa chocolate (LCC:∼55%; 12,61 ± 1,35 mg equivalent of epichatequin/g) and the others ingested a daily dose of 20 g of high cocoa chocolate (HCC:∼90%; 18,19 ± 2,64 mg equivalent of epichatequin/g). A baseline evaluation was performed before the participants started ingesting the assigned chocolate for a 30 days period, after which a final evaluation was performed. Each evaluation included heart ultrasonography, carotid-femoral pulse wave velocity (PWV) and carotid pulse wave analysis (PWA), flow mediated slowing (FMS) and an analysis of the ventricular-arterial coupling (VAC). Results: The baseline evaluation presented similar values within normal range in both groups. The positive vascular effects were overall more distinct in the group eating chocolate with the highest content in cocoa. No structural modifications on the heart were found after the intervention, notwithstanding cardiac function was improved on certain functional parameters in the HCC group only. A statistically significant improvement was depicted over the brachial and central systolic and pulse pressures in the HCC group, and a trend for improvement in the AiX and the FMS was also observed in the HCC but not in the LCC. The VAC parameters were similar at baseline between groups, but showed a significant improvement in the HCC group after intervention, increasing from 0.674 to 0.719 (p = 0.004), so that the post-intervention VAC was significantly higher in the HCC group compared with the LCC group (p < 0.05). In addition, significant variation was observed in both groups regarding arterial elastance, LV elastance, stroke work and potential energy, with greater mean differences identified in the HCC. Conclusions: This study shows that regular consumption of HCC has beneficial effects over the cardiovascular system in young and healthy adults, improving vascular function by reducing central brachial artery pressures, promoting vascular relaxation, and enhancing VAC.