HEALTH NEWS

Study Title:

The Problem of Hibernation Metabolism Following Weight Loss

Study Abstract

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 10% 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 10% 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.

Study Information

Michael Rosenbaum, Jules Hirsch, Dympna A Gallagher and Rudolph L Leibel
Long-term persistence of adaptive thermogenesis in subjects who have maintained a reduced body weight.
American Journal of Clinical Nutrition
2008 October
Columbia University College of Physicians & Surgeons–New York Presbyterian Medical Center, New York, NY