Objective Hypermetabolism in cirrhosis is associated with a high risk of complications and mortality. However, studies about underlying mechanisms are usually focussed on isolated potential determinants and specific etiologies, with contradictory results. We aimed at investigating differences in nutrition, metabolic hormones, and hepatic function between hypermetabolic and nonhypermetabolic men with cirrhosis of the liver. Patients and methods We prospectively enrolled 48 male cirrhotic inpatients. We evaluated their resting energy expenditure (REE) and substrate utilization by indirect calorimetry, body composition by dual-energy X-ray absorptiometry, liver function, and levels of major hormones involved in energy metabolism by serum sample tests. Patients with ascites, specific metabolic disturbances, and hepatocellular carcinoma were excluded. Results REE and REE adjusted per fat-free mass (FFM) were significantly increased in cirrhotic patients. Overall, 58.3% of cirrhotic patients were classified as hypermetabolic. Groups did not differ significantly in age, etiology of cirrhosis, liver function, presence of ascites, use of diuretics, â-blockers, or presence of transjugular intrahepatic portosystemic shunts. Hypermetabolic cirrhotic patients had lower weight, BMI (P< 0.05), nonprotein respiratory quotient (P< 0.01), leptin (P<0.05), and leptin adjusted per fat mass (FM) (P<0.05), but higher FFM% (P< 0.05) and insulin resistance [homeostatic model assessment-insulin resistance (HOMA-IR)] (P<0.05). Only HOMA-IR, leptin/FM, and FFM% were independently related to the presence of hypermetabolism. Conclusion Hypermetabolic cirrhotic men are characterized by lower weight, higher FFM%, insulin resistance, and lower leptin/FM when compared with nonhypermetabolic men. HOMA-IR, FFM%, and leptin/FM were independently associated with hypermetabolism, and may serve as easily detectable markers of this condition in daily clinical practice.