Clinical Abstracts-With Comments by Adriane Fugh-Berman, MD

September 2000; Volume 2; 72

Can a Cup of Cocoa a Day Keep an MI Away?

Source: Rein D, et al. Cocoa inhibits platelet activation and function. Am J Clin Nutr 2000;72:30-35.

Design/Setting/Subjects: Controlled, three-arm study in 30 healthy, nonsmoking subjects 24-50 years old. Ten subjects (four men and six women) were in each group. Subjects ingested a cocoa beverage; a control beverage (containing the same amount of caffeine and sugar as the cocoa beverage), or water. Peripheral blood was taken two and six hours later and platelet activation was measured, utilizing activation-dependent platelet antigens and platelet microparticle formation utilizing labeled monoclonal antibodies and flow cytometry.

Treatment: A 300 ml cocoa beverage was used. The beverage contained 18.75 g procyanidin-enriched cocoa powder (Co-coapro™, Mars, Inc., Hackettstown, NJ) and provided 897 mg total epicatechin and oligomeric procyanadins, 17 mg caffeine, 285 mg theobromine, and 12.5 g sucrose mixed with distilled water. The control beverage contained 17 mg caffeine and 12.5 g sucrose.

Results: Epinephrine or ADP-stimulated expression of fibrinogen-binding confirmation of glycoprotein IIb-IIIa decreased in the cocoa group at both time points tested compared to baseline. These parameters increased after consumption of the caffeine-containing beverage; there was no change in the water group. ADP-stimulated P-selectin expression was also decreased by cocoa. Platelet microparticle formation increased after caffeine and water consumption but decreased after cocoa consumption. In vitro, primary hemostasis in response to epinephrine was inhibited six hours after cocoa consumption; the caffeine-containing beverage inhibited ADP-induced primary hemostasis at two and six hours.

Funding: Not stated. However, Mars Inc. is listed as one of the affiliations.

Comments: Can hot chocolate prevent heart attacks? These results indicate that cocoa inhibits platelet activation and appears to have an aspirin-like effect on platelet function. The authors note that flavonoids may be responsible for all or some of this effect. As the researchers put it, "regular intake of active cocoa components may contribute to a lower thrombotic risk." Good news about chocolate is always welcome. As I write this, I’m eating chocolate-covered soybeans, which didn’t sound like a good idea but are not bad at all. Flavonoids, phytoestrogens, methylxanthines, and sugar all in one product; this candy is a multifunctional food.