doubly labelled water

Doubly labelled water (DLW) is a diagnostic metabolic tracer used to measure the average daily metabolic rate, or total energy expenditure (TEE), in humans over a period of time. It consists of water in which both the hydrogen and oxygen atoms have been replaced with non-radioactive stable isotopes: deuterium (2H) and oxygen-18 (18O). Following oral administration, the deuterium is eliminated from the body exclusively as water, while the oxygen-18 is eliminated as both water and carbon dioxide. By analyzing the differential disappearance rates of these isotopes from urine samples collected over 7 to 14 days, the rate of carbon dioxide production can be calculated, providing a highly accurate estimate of energy expenditure. In clinical research conducted by the University of Edinburgh, DLW is utilized to investigate the physiological mechanisms of weight loss and energy balance changes in patients with Type 1 Diabetes following islet transplantation.

Other names

doubly labeled waterDLW2H218Ostable isotope water