Casual chocolate consumption and inhibition of platelet function.

Observational studies have associated reduced cardiovascular mortality with chocolate consumption. Feeding studies of high-dose, flavanol-rich chocolate show antiplatelet effects, but the effect of casual chocolate consumption on platelet function is unknown. Healthy adults (N=1535) were proscribed from consuming foods affecting platelet function, including chocolate, for 48 hours and completed a 24-hour dietary recall before ex vivo platelet testing with the Platelet Function Analyzer (PFA)-100 (Dade Behring, Inc, Deerfield, IL) test and in vivo testing with urinary 11-dehydro thromboxane B2 (Tx-M) measurements. Some participants (n=141) reported ignoring the prohibition of consuming chocolate before platelet testing. Despite having similar baseline characteristics, chocolate consumers had longer PFA closure times (130 vs 123 seconds, P=.005) and decreased Tx-M levels (175 vs 290 ng/mol creatinine, P=.03). Chocolate remained a significant independent predictor of both ex vivo and in vivo platelet function testing after adjusting for confounders. The authors concluded that even consuming modest amounts of commercial chocolate has important antiplatelet effects.