Persistent Metabolic Adaptation 6 Years After "The Biggest Loser" Competition

Obesity (Silver Spring). 2016 Aug;24(8):1612-9. doi: 10.1002/oby.21538. Epub 2016 May 2.

Abstract

Objective: To measure long-term changes in resting metabolic rate (RMR) and body composition in participants of "The Biggest Loser" competition.

Methods: Body composition was measured by dual energy X-ray absorptiometry, and RMR was determined by indirect calorimetry at baseline, at the end of the 30-week competition and 6 years later. Metabolic adaptation was defined as the residual RMR after adjusting for changes in body composition and age.

Results: Of the 16 "Biggest Loser" competitors originally investigated, 14 participated in this follow-up study. Weight loss at the end of the competition was (mean ± SD) 58.3 ± 24.9 kg (P < 0.0001), and RMR decreased by 610 ± 483 kcal/day (P = 0.0004). After 6 years, 41.0 ± 31.3 kg of the lost weight was regained (P = 0.0002), while RMR was 704 ± 427 kcal/day below baseline (P < 0.0001) and metabolic adaptation was -499 ± 207 kcal/day (P < 0.0001). Weight regain was not significantly correlated with metabolic adaptation at the competition's end (r = -0.1, P = 0.75), but those subjects maintaining greater weight loss at 6 years also experienced greater concurrent metabolic slowing (r = 0.59, P = 0.025).

Conclusions: Metabolic adaptation persists over time and is likely a proportional, but incomplete, response to contemporaneous efforts to reduce body weight.

Trial registration: ClinicalTrials.gov NCT02544009.

MeSH terms

  • Absorptiometry, Photon
  • Adult
  • Basal Metabolism / physiology*
  • Body Composition / physiology
  • Body Mass Index
  • Body Weight / physiology*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Obesity, Morbid / metabolism*
  • Weight Loss / physiology*

Associated data

  • ClinicalTrials.gov/NCT02544009