Protein and fat absorption in prolonged diarrhoea in infancy

15N-yeast protein absorption, nitrogen and fat retention, stool reducing substances, and lactate concentrations were measured in 22 infants who had had severe diarrhoea for 7 days. Stool losses of nitrogen and fat were large, and an appreciable proportion appeared to be endogenous. The supply of nitrogen and energy might have been a limiting factor in tissue repair if stool weight exceeded 30 g/kg body weight a day. These results differ from those in older children with kwashiorkor complicated by diarrhoea of similar severity.