Resting metabolic rate and total energy expenditure in acute and weight recovered patients with anorexia nervosa and in healthy young women.

Because little is known about energy requirements in anorectic patients before and after weight gain we measured resting metabolic rate (RMR) by indirect calorimetry and total energy expenditure (TEE) by the doubly labeled water method in 6 patients with anorexia nervosa (body mass index [BMI] = 15.1 +/- 1.3 kg/m2), in 6 weight-recovered anorectics (BMI = 21.2 +/- 2.1 kg/m2), and in 12 healthy age-matched women (BMI = 20.5 +/- 1.9 kg/m2). No significant differences were found between the weight-recovered anorectic women and the healthy controls in RMR (1,330 +/- 131 kcal/day [weight-recovered]; 1,419 +/- 197 [controls]) and in TEE (2,602 +/- 637 kcal/day [weight-recovered]; 2,596 +/- 493 kcal/day [controls]). The RMR was significantly lower in the acutely ill anorectic patients (1,171 +/- 113 kcal/24 hr) than in weight-recovered anorectics and in healthy controls. The TEE was significantly lower in the anorectic group (1,946 +/- 192 kcal/day) than in the healthy controls.