Several studies have evaluated the effect of food on alcohol pharmacokinetics; however, most studies have used oral alcohol administration, which cannot separate the influence of food on absorption from its influence on alcohol elimination. Alcohol clamping uses intravenous alcohol and provides a direct measure of the alcohol elimination rate (AER). Two studies, using alcohol clamping at 50 mg %, were conducted to investigate the effect of food and food composition on AER (g/h) in healthymen and women. In the first study, 20 subjects underwent two clamping sessions, one after a 12-hour fast and another 1 hour after consuming a 530-calorie breakfast. In the second study, 8 subjects underwent four clamping sessions: one after a 12-hour fast and, in each of three "fed" sessions, 1 hour after a 550-calorie high-fat, high-protein, or high-carbohydrate breakfast. Comparison of AERs from the first study showed an average 25% increase following food compared to thatfollowingfasting. Men showed significantly higher AERs compared to women; however, the food effect was similar in both genders. In the second study, the AER showed a significant average 45% increase following the meal, regardless of composition, compared with that following fasting. These findings indicate that food intake results in increased alcohol elimination rates. The increase was similar for meals of different compositions, suggesting that the food effect is not due to specific interactions with meal constituents. Probable mechanisms for the increased alcohol elimination includefood-induced increases in hepatic blood flow and in the activity of alcohol-metabolizing enzymes.