The absorption and elimination characteristics of alcohol have been studied in healthy fasted and nonfasted human volunteers using low single doses. In non-fasted subjects, carbohydrate reduced overall alcohol bioavailability by about 96 percent, compared to 90 per cent for fat and 75 per cent for protein. Inhibition of absorption in nonfasted subjects appeared to be due to less alcohol being available for absorption rather than a reduced absorption rate. Serum alcohol levels in fasted subjects were interpreted in terms of both first-order and zero-order absorption followed by first-order elimination. Of the two proposed models, that utilizing zero-order absorption provided a marginally better fit to observed data.