Research

Hormonal

Leptin resistance, caused by defects in blood-brain barrier transport or intracellular signaling (e.g., SOCS3), is the primary driver of common obesity, whereas absolute leptin deficiency is rare.

In common obesity, your body produces plenty of leptin (the satiety hormone), but your brain stops listening to it. This 'leptin resistance' is a key biological barrier to weight loss.

StrongQualifiesVERY_HIGH confidence
However, absolute leptin deficiency is an uncommon cause of human obesity. Instead, leptin resistance results from defects in transport across the blood-brain barrier or impaired intracellular signaling. Suppressor of cytokine signaling 3 (SOCS3) is an intracellular protein that acts to limit leptin signaling and is an important mediator of leptin resistance.
Michael K. Badman et al. · Science · 2005

Why this rating

The paper presents this as a well-established consensus in the field of endocrinology.

Source

The Gut and Energy Balance: Visceral Allies in the Obesity Wars

Michael K. Badman et al. · Science · 2005

DOI 10.1126/science.1109951

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DOI resolved against Crossref · corpus check 2026-06-10

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