Differential responses of serum gamma-glutamyltransferase to alcohol intake in Japanese males.

We studied the association of gamma-glutamyltransferase (GGT) and other serum markers of liver injury with daily alcohol consumption in a healthy population of 1,043 Japanese males. A positive correlation between daily alcohol consumption and biochemical markers, such as log GGT (r = 0.432), log AST (r = 0.244) or log LAP (r = 0.246), was seen in all drinkers. However, there was a negative correlation, such as log GGT (r = -0.434), log AST (r = -0.424) or log LAP (r = -0.430), in heavy drinkers who consumed more than 70 g ethanol a day. On the other hand, a positive correlation, such as log GGT (r = 0.426), log AST (r = 0.247) or log LAP (r = 0.216) was found in moderate drinkers who consumed less than 70 g ethanol a day. Interestingly, there was a tendency toward negative association between alcohol consumption and the Tokyo University ALDH2 Phenotype Screening Test (TAST) score in the heavy drinkers, and there was a tendency toward positive association between GGT and TAST score in this group. Our results suggest that there are 2 groups of drinkers, those with elevated GGT (good responders) and those with normal GGT (poor responders) despite heavy drinking.