Influence of Drinking Conditions on Alcohol Metabolism in Healthy Men with <i>ALDH</i>2*1/*1 Genotype: Comparison between Different Alcoholic Drinks with or without Meal

Abstract

The influence of drinking conditions on alcohol metabolism and drunkenness was investigated in healthy men with ALDH2*1/*1 genotype aged from 40 to 60 who were occasional or habitual drinkers. The investigation was performed by open intersection competitive drinking tests at an ethanol dose of 0.32 g/kg under 4 different drinking conditions: beer without a meal [B(–)], shochu (a distilled spirit) without a meal [S(–)], beer with a meal [B(+)] and shochu with a meal [S(+)]. The blood alcohol concentration (BAC) and BAC-AUC (area under the curve) were lower in the B(–) than in the S(–). The blood acetaldehyde concentration (BAcH) and the serum acetate concentration (SAce) were also lower in the B(–) than in the S(–). The meal markedly decreased BAC, BAC-AUC and BAcH-AUC for both alcoholic beverages. Subjective drunkenness was stronger in order of B(+) < S(+) < B(–) < S(–), depending on BAC. Ethanol degradation rate (EDR: mg/kg/h) was higher in order of S(–) < B(–) < S(+) < B(+), which may be caused by differences in the numbers of glucide calories in the drinking conditions because some glucide is contained in beer (3.0 g/100 ml) but not in the spirit shochu. The ratio of lactic acid to pyruvic acid in the blood, which reflects the ratio of NADH/NAD + in liver cells, was higher in the S(–) than in the B(–), and was decreased by the meal for both alcoholic beverages. These results suggested that glucide increase the rate of alcohol metabolism by supplying pyruvic acid to decrease the ratio of NADH/NAD + , which lowers BAC and relieves drunkenness. Thus, the intake of glucide calories while drinking is important to reduce the pharmacological and toxicological actions of alcohol.