Drinking and Obesity: Alcoholic Liver Disease/Nonalcoholic Fatty Liver Disease Interactions.

Alcohol and obesity are the main risk factors for alcoholic liver disease and nonalcoholic fatty liver disease (NAFLD), respectively, and they frequently coexist. There are considerable synergistic interaction effects between hazardous alcohol use and obesity-associated metabolic abnormalities in the development and progression of fatty liver disease. Intermittent binge-drinking has been shown to promote steatohepatitis from obesity-related steatosis, and binge-drinking is associated with progression to cirrhosis even when average alcohol intake is within the currently used criteria for a NAFLD diagnosis. Recent longitudinal studies in NAFLD have shown that light-to-moderate alcohol use is associated with fibrosis progression and incident clinical liver disease, suggesting that there is no liver-safe limit of alcohol intake in the presence of NAFLD; a J: -shaped association between alcohol and all-cause mortality remains controversial. The interaction effects between alcohol and obesity make the present strict dichotomization of liver disease into alcoholic and NAFLD inappropriate, and require attention in future research, public health policy, individual counseling, and risk stratification.