Changes in body composition and resting energy expenditure after rapid weight loss: is there an energy-metabolism adaptation in obese patients?

Identifier:  PC:1604

Handle: https://hdl.handle.net/20.500.11797/PC1604

Authors:  J Salas Salvado; S Valtueña; S Blanch; M Barenys; R Solà

Abstract:
The aim of this study was to assess changes in resting energy expenditure (REE) related to changes in fat free mass (FFM) in nine morbid obese (BMI 43 +/- 5.1 kg/m2) hospitalised females on VLCD. REE was measured by 30 min indirect calorimetry before and after 28 days of hospitalisation. Changes in FFM were assessed by bioelectrical impedance analysis (BIA), hydrostatic weighing (HW) and nitrogen balance (N). REE decreased 11.5% from 7.8 +/- 1.0 to 6.9 +/- 0.8 MJ/d. Total weight loss was 8.4 +/- 1.9 kg or 7.4% with an estimated FFM loss of 3.4 +/- 1.8 (BIA), 2.9 +/- 1.9 (HW) and 1.8 +/- 1.0 (N). As the fall in REE was larger than the loss of FFM, it is concluded that morbid obese patients develop an energy saving adaptation during rapid weight loss.