STATEMENT: WEIGHT REGAIN IS NOT INFLUENCED BY SLOWDOWN OF RESTING METABOLIC RATE DUE TO WEIGHT LOSS
Journal: Persistent metabolic adaptation 6 years after “The Biggest Loser” competition
Author: Fothergill E, Guo Juen, Howard Lilian, Kerns Jennifer C, Knuth Nicolas D, Brychta Robert, Chen Kong Y, Skarulis Monica C, Walter Mary, Walter Peter J, Hall Kevin D
Weight loss is accompanied by a slowing of resting metabolic rate (RMR) that is often greater than would be expected based on the measured changes in body composition. This phenomenon is called “metabolic adaptation” or “adaptive thermogenesis,” and it acts to counter weight loss and is thought to contribute to weight regain (1, 2).
Metabolic adaptation acts to decrease energy expenditure and thereby impedes the rate of weight loss during an intervention. However, “The Biggest Loser” participants with the greatest weight loss at the end of the competition also experienced the greatest slowing of RMR at that time (3). Similarly, those who were most successful at maintaining lost weight after 6 years also experienced greater ongoing metabolic slowing. These observations suggest that metabolic adaptation is a proportional, but incomplete, response to contemporaneous efforts to reduce body weight from its defended baseline or “set point” value (14).
Metabolic adaptation persists over time and is likely a proportional, but incomplete, response to contemporaneous efforts to reduce body weight.
In conclusion, we found that “The Biggest Loser” participants regained a substantial amount of their lost weight in the 6 years since the competition but overall were quite successful at long‐term weight loss compared with other lifestyle interventions. Despite substantial weight regain, a large persistent metabolic adaptation was detected. Contrary to expectations, the degree of metabolic adaptation at the end of the competition was not associated with weight regain, but those with greater long‐term weight loss also had greater ongoing metabolic slowing. Therefore, long‐term weight loss requires vigilant combat against persistent metabolic adaptation that acts to proportionally counter ongoing efforts to reduce body weight.