Research

Hormonal

Leptin replacement therapy in adults with genetically confirmed leptin deficiency causes profound weight loss, resolution of type 2 diabetes, and recovery of hypogonadism.

If you have a rare genetic condition causing leptin deficiency, leptin replacement therapy can reverse morbid obesity, diabetes, and hypogonadism. However, this does not apply to the vast majority of people with common obesity, who typically have high leptin levels but are resistant to its effects. This treatment is not a general weight-loss solution for the general population.

ModerateSupportsMEDIUM confidence
We document here that leptin replacement therapy in leptin-deficient adults with established morbid obesity results in profound weight loss, increased physical activity, changes in endocrine function and metabolism, including resolution of type 2 diabetes mellitus and hypogonadism, and beneficial effects on ingestive and noningestive behavior.
Júlio Licinio et al. · Proceedings of the National Academy of Sciences · 2004

Why this rating

N=3 case series; highly specific genetic population limits generalizability.

Source

Phenotypic effects of leptin replacement on morbid obesity, diabetes mellitus, hypogonadism, and behavior in leptin-deficient adults

Júlio Licinio et al. · Proceedings of the National Academy of Sciences · 2004

DOI 10.1073/pnas.0308767101

case_series · n=3Cited 504×
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DOI resolved against Crossref · corpus check 2026-06-10

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