The comparative effectiveness of oral administration of fructose, glucose sucrose and alanine has been investigated on the rates of blood alcohol clearance, and acetaldehyde removal in man. Oral administration of fructose was found to exert the most pronounced effect. It increased the rate of blood alcohol clearance by about 100%. Orally administered alanine was found to be least effective in increasing the rate of blood alcohol clearance after blood alcohol had reached peak levels, perhaps due that poor absorption of alanine. Fructose administration partially prevented the ethanol-mediated increase inlactate/pyruvate and beta-hydroxybutyrate/acetoacetate in the blood. Fructose exerted the most pronounced antiketogenic effect and the levels of circulating free fatty acids decreased in the 24-hour fasted patients upon administration of fructose with ethanol compared to ethanol alone. Oral administrations of fructose, glucose, sucrose or alanine did not significantly change the levels of acetaldehyde in the blood. Combined administration of fructose with ethanol resulted in an increase in the levels of blood sorbitol. The mechanism through which fructose exerts its stimulatory effect on the metabolism of ethanol in the liver has been discussed.