The objective of this study was to examine the relationship of alcohol consumption to target organ involvement and ambulatory blood pressure (BP) in a population of young borderline to mild hypertensive subjects. Participants were 793 male subjects, aged 18-45 years, from the HARVEST Study. The analysis was performed in three age-matched groups with similar body mass index. Casual and 24-h ambulatory BP monitoring, routine biochemistry, echocardiography, and albumin excretion rate were measured. The men were divided into three groups: 1) nondrinkers, 2) drinkers of < 50 g/day, and 3) drinkers of > or = 50 g/day. Office systolic BP was not significantly different among the three groups, whereas 24-h and daytime BPs increased progressively from the first to the third group (group 1 v 3; P = .01 for 24-h systolic BP and P = .02 for daytime systolic BP). These differences remained significant even after adjusting for smoking. Left ventricular mass index, interventricular septum thickness, and wall thickness increased progressively from group 1 to group 3; this difference also remained significant after adjusting for smoking and 24-h BPs. The albumin excretion rate was much higher in group 3 than in group 1 (P = .003), but when 24-h BP was added to the model the difference was no longer significant. These results indicate that alcohol has a detrimental effect on the heart and the kidney. Alcohol's effect on LV wall thickness appears to be direct, whereas its action on albumin excretion rate seems to be mediated mainly by its effect on BP.