Dark Chocolate May Improve Vascular Function in Smokers
Study suggests effect may be due to antioxidants found in dark but not white chocolate
THURSDAY, Dec. 22 (HealthDay News) -- Dark chocolate contains antioxidants that may reduce the negative effects of smoking on platelet reactivity and endothelial cell function, and lower smokers' risks of developing atherosclerosis, according to a scientific letter published in the January issue of Heart.
Roberto Corti, M.D., of the University Hospital, Zurich, Switzerland, and colleagues randomly assigned 20 male smokers to eat either 40 grams of dark chocolate (74% cocoa solids) or 40 grams of white chocolate. At baseline and two hours after the subjects ate the chocolate, the researchers assessed endothelial cell function by flow-mediated dilatation (FMD) and measured platelet reactivity by an in vitro shear stress assay.
The investigators found that dark chocolate improved FMD from 4.4% to 7%, an effect that lasted up to eight hours, but that white chocolate had no effect on FMD. They also noted that dark chocolate decreased platelet adhesion from 5% to 3%, but that white chocolate had no effect. The authors determined that total antioxidant status increased significantly in the dark-chocolate group but not in the white-chocolate group.
"Dark chocolate has a much higher polyphenol (a heterogeneous group of antioxidants) content per gram than do other antioxidant-rich foods such as wine, tea or berries," the authors write. "Therefore, only a small daily treat of dark chocolate may substantially increase the amount of antioxidant intake and beneficially effect vascular health."
The study was funded by the Swiss National Research Foundation.