Characteristics of the included trials investigating the acute effects of grape polyphenols.

R, randomized; DB, double-blind; PC, placebo-controlled; CO, crossover; FMD, flow-mediated dilation.1Study designed alcoholized group and de-alcoholized group to investigate the effects of grape polyphenols on FMD; therefore, we separated the study into 2 trials: alcoholized trial and de-alcoholized trial.2Karatzi’s study designed red wine+olive group and red wine+green olive group to investigate the effect of grape polyphenols on FMD respectively, so we separated Karatzi’s study into 2 trials: olive trial and green olive trial.