Long-term persistence of adaptive thermogenesis in subjects who have maintained a reduced body weight

• Published in: The American journal of clinical nutrition Vol. 88; no. 4; pp. 906 - 912
• Main Authors: Rosenbaum, Michael, Hirsch, Jules, Gallagher, Dympna A, Leibel, Rudolph L
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Nutrition 01.10.2008; American Society for Clinical Nutrition; American Society for Clinical Nutrition, Inc
• Subjects: adaptation; Adaptation, Physiological; Adult; Basal Metabolism - physiology; Biological and medical sciences; body composition; Body Composition - physiology; body weight; calorimetry; Calorimetry, Indirect; Circadian Rhythm; Diet, Reducing; energy balance; energy expenditure; Energy Intake - physiology; Energy Metabolism - physiology; Feeding. Feeding behavior; Female; Food, Formulated; Fundamental and applied biological sciences. Psychology; heat production; Human body; Humans; liquid diet; Male; Metabolism; Nutrition; Obesity - diet therapy; Obesity - metabolism; physical activity; resting energy expenditure; Thermogenesis - physiology; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Weight; Weight control; weight loss; Weight Loss - physiology; Human; Thermogenesis; Long term; Body weight; WHO
• ISSN: 0002-9165; 1938-3207; 1938-3207
• DOI: 10.1093/ajcn/88.4.906

BACKGROUND: After weight loss, total energy expenditure--in particular, energy expenditure at low levels of physical activity--is lower than predicted by actual changes in body weight and composition. An important clinical issue is whether this reduction, which predisposes to weight regain, persists over time. OBJECTIVE: We aimed to determine whether this disproportionate reduction in energy expenditure persists in persons who have maintained a body-weight reduction of greater-than-or-equal10% for >1 y. DESIGN: Seven trios of sex- and weight-matched subjects were studied in an in-patient setting while receiving a weight-maintaining liquid formula diet of identical composition. Each trio consisted of a subject at usual weight (Wtinitial), a subject maintaining a weight reduction of greater-than-or-equal10% after recent (5-8 wk) completion of weight loss (Wtloss₋recent), and a subject who had maintained a documented reduction in body weight of >10% for >1 y (Wtloss₋sustained). Twenty-four-hour total energy expenditure (TEE) was assessed by precise titration of fed calories of a liquid formula diet necessary to maintain body weight. Resting energy expenditure (REE) and the thermic effect of feeding (TEF) were measured by indirect calorimetry. Nonresting energy expenditure (NREE) was calculated as NREE = TEE - (REE +TEF). RESULTS: TEE, NREE, and (to a lesser extent) REE were significantly lower in the Wtloss₋sustained and Wtloss₋recent groups than in the Wtinitial group. Differences from the Wtinitial group in energy expenditure were qualitatively and quantitatively similar after recent and sustained weight loss. CONCLUSION: Declines in energy expenditure favoring the regain of lost weight persist well beyond the period of dynamic weight loss.