Energy balance

The doubly labeled water technique provides accurate measurements of total energy expenditure in healthy adults when performed in experienced laboratories, but significant between-laboratory variability exists that can lead to physiologically impossible results in less experienced settings.

If you are using Doubly Labeled Water to measure energy expenditure, ensure your laboratory is experienced with the technique. The method is accurate, but results vary significantly between labs. Use standardized isotope standards and calculation methods (like the 2-point or modified methods) to minimize error, especially if your subject has a low ratio of water intake to energy expenditure.