Previous research has indicated that consumption of high amounts of cocoa-containing foods can lower blood pressure (BP), believed to be due to the action of the cocoa polyphenols (a group of chemical substances found in plants, some of which, such as the flavanols, are believed to be beneficial to health). “A particular concern is that the potential BP reduction contributed by the flavanols could be offset by the high sugar, fat and calorie intake with the cocoa products, ” the authors write. The effect of low cocoa intake on BP is unclear.

Dirk Taubert, M.D., Ph.D., of University Hospital of Cologne, Germany, and colleagues assessed the effects of low regular amounts of cocoa on BP. The trial, conducted between January 2005 and December 2006, included 44 adults (age 56 through 73 years; 24 women, 20 men) with untreated upper-range prehypertension (BP 130/85 – 139/89) or stage 1 hypertension (BP 140/90 – 160/100). Participants were randomly assigned to receive for 18 weeks either 6.3g (30 calories) per day of dark chocolate containing 30mg polyphenols or matching polyphenol-free white chocolate.