Weight loss, weight maintenance, and adaptive thermogenesis.

BACKGROUND: Diet-induced weight loss is accompanied by adaptive ie, a disproportional or greater than expected reduction of resting rate (RMR). OBJECTIVE: The aim of this study was to investigate whether thermogenesis is sustained during weight maintenance after weight loss. Subjects were 22 men and 69 women [mean +/- SD age: 40 +/- 9 y; body (BMI; in kg/m2): 31.9 +/- 3.0]. They followed a very-low-energy diet for followed by a 44-wk period of weight maintenance. Body composition was with a 3-compartment model based on body weight, total body water dilution), and body volume. RMR was measured (RMRm) with a ventilated addition, RMR was predicted (RMRp) on the basis of the measured body RMRp (MJ/d) = 0.024 x fat mass (kg) + 0.102 x fat-free mass (kg) + 0.85. Measurements took place before the diet and 8, 20, and 52 wk after the the diet. RESULTS: The ratio of RMRm to RMRp decreased from 1.004 +/- before the diet to 0.963 +/- 0.073 after the diet (P < 0.001), and the was sustained after 20 wk (0.983 +/- 0.063; P < 0.01) and 52 wk (0.984 P < 0.01). RMRm/RMRp was correlated with the weight loss after 8 wk (P < 20 wk (P < 0.05), and 52 wk (P < 0.05). CONCLUSION: Weight loss results adaptive thermogenesis, and there is no indication for a change in thermogenesis up to 1 y, when weight loss is maintained. This trial was registered at clinicaltrials.gov as NCT01015508