Research

Hormonal

Long-term weight loss maintenance is physiologically opposed by metabolic adaptation (reduced energy expenditure) and hyperphagia (increased appetite), driven by neuroendocrine signals like leptin, making weight regain the default biological state.

Understand that after weight loss, your body biologically fights to regain weight through increased hunger and slower metabolism. This is not a failure of willpower but a physiological defense. Successful maintenance requires acknowledging this biological reality and often necessitates ongoing, lifelong behavioral or medical support to counter these natural drives.

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Following weight loss, this seemingly 'simple' feedback system is perturbed by internal physiological processes that oppose further weight loss and make it very difficult to maintain the newly achieved body mass... Adaptive increases in appetite and declines in expenditure occur in response to weight loss.
Emily W. Flanagan et al. · Obesity · 2023

Why this rating

Based on multiple landmark studies (CALERIE, Biggest Loser) and consistent findings across behavioral, surgical, and pharmacological interventions.

Source

New insights in the mechanisms of weight‐loss maintenance: Summary from a Pennington symposium

Emily W. Flanagan et al. · Obesity · 2023

narrative_reviewCited 34×
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