Two patients with malabsorption syndrome and weight loss refractory to conventional pharmacologic and dietary therapy were evaluated on a metabolic ward. Baseline studies indicated moderate to severe protein-energy malnutrition, and severe energy, fat, and nitrogen malabsorption. Metabolic balance studies on low-fat elemental formulas infused nasoenterally over 18-hour periods indicated improved retention of nitrogen, phosphorus, calcium, magnesium, and energy when compared with a solid food diet. Because this dietary modification appeared to correct their malabsorption, both patients learned to insert the nasoenteral tube themselves, and a low-calorie solid-food diet combined with nocturnal tube feedings was continued at home. During the next 9 to 12 months, both patients had increases in body weight, and in the mass of fat-free tissue, skeletal muscle, and fat. This therapeutic approach may correct life-threatening semistarvation in selected patients.