Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive muscle atrophy and weakness. Although dysphagia is a universal feature of this illness, the nutritional and metabolic status of ALS patients has received little attention. We performed serial measurements of muscle power, body composition, energy expenditure, nitrogen balance, and dietary intake on ALS patients on three occasions over 6 mo in the General Clinical Research Center of the University of Kentucky Medical Center. Data were analyzed in reference to the time of death. Regression analysis demonstrated progressive decreases in body fat, lean body mass, muscle power, and nitrogen balance and an increase in resting energy expenditure as death approached. The changes in body composition were greater in males. Energy and protein consumption averaged 84% and 126% of the recommended dietary allowances, respectively, but did not correlate with complaints of dysphagia. We conclude that ALS patients have a chronically deficient intake of energy and recommended augmentation of energy intake rather than the consumption of high-protein nutritional supplements.