Research

Hormonal

Exogenous leptin administration is safe and produces statistically significant but clinically modest weight loss in humans, primarily in those with leptin deficiency, while most obese individuals exhibit leptin resistance.

Leptin therapy is safe and can lead to weight loss, but it is not a cure-all for obesity. It works best for the rare individuals who are truly leptin-deficient. For the majority of obese people who have high leptin levels (leptin resistance), the weight loss is modest and similar to other existing medications. Daily injections are required, though side effects are generally mild (skin redness).

ModerateQualifiesMEDIUM confidence
Phase I and II trials recently showed that leptin administration to humans is safe... leptin treatment in addition to a diet reduced by 500 kcal/d resulted in highly variable but statistically significant weight reduction... most obese people have high endogenous leptin levels, indicating leptin resistance... therapy with leptin is expected to be efficacious in the few persons with leptin deficiency.
Christos S. Mantzoros · Annals of Internal Medicine · 1999

Why this rating

Based on Phase I/II trials and a case study of a leptin-deficient patient; Phase III results are noted as ongoing or pending confirmation.

Source

The Role of Leptin in Human Obesity and Disease: A Review of Current Evidence

Christos S. Mantzoros · Annals of Internal Medicine · 1999

DOI 10.7326/0003-4819-130-8-199904200-00014

narrative_reviewCited 587×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →