Comparison of body protein metabolism during total parenteral nutrition using glucose or glucose and fat as the energy source

Direct measurement of body protein metabolism using L-(1-14C) leucine during total parenteral nutrition following cholecystectomy demonstrated no significant difference between isocaloric isonitrogenous regimens containing glucose alone (n = 5) or with a fat emulsion (n = 5) as the energy substrates. It would appear that providing the obligatory requirement for glucose is met (about 150g d(-1)), fat and carbohydrate calories are inter-changeable with regards to fueling protein metabolism in the early period following moderately severe trauma.