Background: Malnutrition is common in alcoholic cirrhosis. Bedside nutritional assessment techniques may be unreliable in patients with chronic liver disease. The aim of this study was to quantify changes in body composition and compare methods for measuring body composition in alcoholic cirrhosis. Methods: Thirty-eight men with alcoholic cirrhosis were compared with 16 age-matched healthy men. Body composition was assessed using anthropometry and bioelectrical impedance to determine fat-free mass and body fat, deuterium oxide dilution to measure total body water, in vivo neutron activation analysis to measure total body protein, and dual energy x-ray absorptiometry to measure bone mineral content and total body fat mass. Results: With increasing severity of cirrhosis, total body water increased, whereas total body protein decreased with a significant decrease in serum albumin levels. Total body protein levels, expressed as an index, were a more sensitive indicator of protein depletion than serum albumin levels. When patients were assessed by anthropometry and bioelectrical impedance for fat-free mass, there was no reduction compared with controls. Conclusions: Anthropometry and bioelectrical impedance do not accurately reflect changes in body composition associated with chronic liver disease. Quantification of body composition changes in alcoholic cirrhosis requires the use of direct methods such as in vivo neutron activation analysis, dual energy x-ray absorptiometry, or deuterium oxide dilution.