Research
Hormonal
Leptin therapy is effective for weight loss only in patients with leptin deficiency (low circulating levels), not in those with leptin resistance (high levels).
Leptin injections are only effective for people with a specific genetic deficiency causing low leptin levels. For most people with obesity, leptin levels are high, and leptin injections do not work.
GoodQualifiesHIGH confidence
Treatment of patients with leptin mutations with recombinant leptin markedly reduces food intake and causes profound weight loss. However, leptin has no effect in animals or patients carrying the other obesity mutations, each of which abrogates leptin signaling.
Why this rating
Based on genetic studies and clinical trials in specific subgroups.
Source
On the causes of obesity and its treatment: The end of the beginning
Jeffrey M. Friedman · Cell Metabolism · 2025
DOI 10.1016/j.cmet.2025.01.026
narrative_reviewCited 21×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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