Measurement of energy expenditure

Abstract

At the present state of the art, energy expenditure is measured with indirect calorimetry, where energy production is calculated from oxygen consumption, carbon dioxide production and urine-nitrogen loss. Daily energy expenditure consists of three components, i.e., maintenance expenditure, diet-induced energy expenditure and activity-induced energy expenditure. Designing studies to evaluate intervention effects on energy expenditure, including drugs, should be based on the energy expenditure component as targeted. The indicated method for the measurement of maintenance expenditure and diet-induced energy expenditure is a respiration chamber or a ventilated hood. Activity-induced energy expenditure is measured under free-living conditions with doubly labelled water. Energy expenditure can additionally be estimated with prediction equations for maintenance expenditure, based on height, weight, age and gender; doubly labelled water validated accelerometers to assess activity-induced energy expenditure; and measurements of food intake as evaluated with the doubly labelled water technique.