Coffee consumption and serum aminotransferases in middle-aged Japanese men

We investigated the relation between coffee drinking and serum aspartate am inotransferase (AST) and alanine aminotransferase (ALT) concentrations amon g 7313 Japanese men receiving a health examination, excluding former alcoho l drinkers and men with a history of chronic liver disease. Serum AST > 40 and/or ALT > 40 U/L was defined as liver inflammation. Adjustment was made for alcohol use, smoking, body mass index, serum marker for hepatitis virus infection, and other possible confounders. Adjusted odds ratios of liver i nflammation were 1.00 (reference), 0.80, 0.69, and 0.61 for men drinking < 1, 1-2, 3-4, and greater than or equal to 5 cups of coffee daily, respectiv ely. Among 6898 men without liver inflammation, serum AST and ALT were inve rsely associated with coffee consumption, and alcohol-related rise in AST w as attenuated with coffee drinking. These findings suggest coffee may have an effect of suppressing the rise of serum aminotransferase, partly by inhi biting the alcohol-related elevation. Studies regarding biological mechanis m are warranted. (C) 2001 Elsevier Science Inc. All rights reserved.