Dark chocolate inhibits platelet aggregation in healthy volunteers

Abstract number: P2002

Kennedy G., Innes A. J., Mclaren M., Belch J. J. F.

University of Dundee, UK

Introduction  

Cardiovascular disease (CVD) is well know as one of the major causes of death in Scotland. Flavonoids, found in red wine, fruit and vegetables, through a cardioprotective mechanism, have produced the ‘French Paradox’ of longevity. Flavonoids reduce platelet activation and hence atherogenesis and CVD. Flavonoids are also found in the cocoa fraction of chocolate, and thus chocolate may have cardioprotective potential. The aim of this study was to determine the ex vivo effects of chocolate on platelet activity in healthy volunteers.

Methods  

Thirty healthy volunteers were randomized to receive 100 g of either white, milk or dark chocolate. Pre-chocolate baseline, and 4 h postchocolate venous blood samples were obtained, and three measures of platelet function were undertaken: Platelet rich plasma aggregation (PRPA), Whole blood platelet aggregation (WBPA) and platelet nitric oxide (NO) production.

Results  

White chocolate had no effect on platelet function. Milk chocolate demonstrated a trend towards reduced function, but most results were not statistically significant. Dark chocolate reduced 1 and 0.5 mg mL^-1 collagen stimulated PRPA by 12% (P = 0.025) and 92% (P = 0.028), respectively. Collagen-stimulated WBPA was reduced by 16% (P = 0.049) and spontaneous unstimulated WBPA also demonstrated a trend towards reduced aggregation (14% reduction (P = 0.069)). In the dark chocolate group there was a reduction in plasma NO before (26%) and after aggregation (14%), however, this was only significant in the post aggregation data set (P = 0.018).

Conclusion  

Dark chocolate acutely reduces platelet activity, and has potential to reduce CVD and thromboembolic disease.