Alcohol consumption is associated with high concentrations of urinary hydroxytyrosol ; BACKGROUND: Previously, we reported the presence of hydroxytyrosol in red wine and higher human urinary recovery of total hydroxytyrosol than that expected after a single red wine intake. We hypothesized that the alcohol present in wine could promote endogenous hydroxytyrosol generation. OBJECTIVE: The objective was to assess the relation between alcohol consumption and urinary hydroxytyrosol concentrations. DESIGN: This was a cross-sectional study with baseline data from a subsample of the PREvención con DIeta MEDiterránea (PREDIMED) trial, an intervention study directed at testing the efficacy of the Mediterranean diet on the primary prevention of cardiovascular disease. Participants included 1045 subjects, aged 55-80 y, who were at high cardiovascular risk. Alcohol consumption was estimated through a validated food-frequency questionnaire. Urinary hydroxytyrosol and ethyl glucuronide, a biomarker of alcohol consumption, were measured. RESULTS: Urinary ethyl glucuronide concentrations were directly related to alcohol and wine consumption (P 20 g (2 drinks)/d and >10 g (1 drink)/d alcohol in men and women, respectively, were associated (P