Research

Hormonal

Restoring leptin levels to pre-weight loss concentrations reverses brain activity changes and metabolic adaptations (increased energy expenditure) induced by caloric restriction, thereby sustaining weight loss.

If you have lost weight, your body fights back by lowering leptin, which increases hunger and slows metabolism. This paper suggests that replacing leptin to pre-weight-loss levels can stop this fight-back mechanism. However, this is not a general weight-loss drug for currently obese people, as most have high leptin and don't respond to it. It may be relevant for a small subset of obese individuals with low leptin levels.

GoodSupportsHIGH confidence
Restoration of leptin levels maintained weight loss and reversed the changes in brain activity. Thus, leptin is a critical factor linking reduced energy stores to eating behavior. Potentially, leptin therapy could sustain weight loss by overriding the tendency toward energy conservation.
Rexford S. Ahima · Journal of Clinical Investigation · 2008

Why this rating

Based on human clinical trials (Rosenbaum et al.) using fMRI and metabolic measurements, though it is a commentary summarizing other studies.

Source

Revisiting leptin’s role in obesity and weight loss

Rexford S. Ahima · Journal of Clinical Investigation · 2008

DOI 10.1172/jci36284

narrative_reviewCited 197×
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DOI resolved against Crossref · corpus check 2026-06-10

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