Research

Hormonal

Chronic caloric overfeeding resulting in a 10% weight gain causes a more than 3-fold elevation in basal serum leptin levels in healthy humans, correlating linearly with increased body fat percentage.

Gaining 10% of your body weight through overfeeding causes your leptin levels to triple. This is a normal physiological response to increased fat mass, not a malfunction. The paper suggests this high leptin state is associated with the development of leptin resistance, where the body's ability to use leptin to regulate energy balance is impaired.

GoodSupportsHIGH confidence
the weight gain due to overfeeding resulted in a more than 3-fold elevation of basal serum leptin at both 5 and 7 weeks (2.0 + 0.4 vs. 6.5 + 1.2 vs. 6.07 + 1.0 ng/mL; P < 0.02)... The magnitude of the leptin rise and the change in the percentage of body fat showed a linear correlation (r = 0.88; P < 0.01).
Jerzy W. Kolaczynski et al. · The Journal of Clinical Endocrinology & Metabolism · 1996

Why this rating

Controlled clinical trial with healthy subjects, clear statistical significance, but small sample size (n=8).

Source

Response of leptin to short-term and prolonged overfeeding in humans.

Jerzy W. Kolaczynski et al. · The Journal of Clinical Endocrinology & Metabolism · 1996

DOI 10.1210/jcem.81.11.8923877

clinical_trial · n=14Cited 409×
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DOI resolved against Crossref · corpus check 2026-06-10

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