The Relationship between Coffee Drinking and Liver Function Tests in Korean Men

Abstract

Background: Coffee is known to have a protective effect on liver enzymes. There are a limited number of Asian studies on this subject. We investigated the relationship between coffee and liver function tests in Korean men on a large scale. Methods: Study participants were consecutive men who had a regular health checkup in a university hospital in Korea. Information on coffee intake, alcohol drinking, and smoking was collected through selfadministered questionnaires. Results: A total of 3,844 men were enrolled in this study. Coffee drinking was positively associated with smoking and alcohol drinking. Coffee drinking was inversely associated with aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) concentrations (r = À1.33, p = 0.008 and r = À6.35, p = 0.007, respectively). Also, increasing levels of coffee consumption was inversely associated with AST and GGT in a multivariate model ( p < 0.001 and p < 0.001, respectively). The relationship between coffee drinking status and alanine aminotransferase (ALT) did not reach statistical significance. However, heavy coffee consumption ( ‡ 3 cups/day) was significantly inversely related to ALT compared with mild coffee consumption ( < 1 cup/day) and non-coffee drinkers in multivariate analyses ( p = 0.032). All multivariate models were adjusted for age, body mass index, regular exercise, smoking amount, and alcohol drinking status. Conclusions: Coffee drinking was inversely associated with AST and GGT in apparently healthy Korean men. The relationship showed a dose-response pattern. It was suggested that ALT was lower in heavy coffee consumers ( ‡ 3 cups/day) compared with mild coffee consumers ( < 1 cup/day) and non-coffee drinkers.