Doubly Labeled Water for Maintenance Energy

The energy intake required for weight maintenance during baseline and the subsequent energy deficit prescribed to achieve the desired caloric restriction were calculated from 4-week data including two 14-day periods by doubly labeled water (DLW). During the first DLW study (B1) participants followed their usual diet at home. During the second DLW study (B2), participants were provided with a weight maintenance diet. During B2, subjects were weighed every morning and changes in body weight were obtained by regression analysis every 3 days over the 2 week period and energy intake was adjusted as needed to maintain a stable body weight (<±250 g). Values from the animal literature for tissue gain or loss were used to assign energy values to weight changes as previously described [11] (link) and adjustments were made to determine energy intake for weight maintenance. Individual energy requirements were then calculated as the average of total daily energy expenditure (TDEE) during B1 and the final energy intake for weight maintenance (after adjustments) during B2.