Research

Hormonal

Obese individuals typically exhibit high circulating leptin levels (hyperleptinaemia) due to increased fat mass, yet fail to lose weight, indicating a state of leptin resistance rather than deficiency.

If you are obese, your leptin levels are likely high, not low. Your body is resistant to the signal. Simply having more leptin (or taking supplements) will not work because the signal is already present but ignored. Focus on strategies that may improve sensitivity rather than assuming a deficiency.

GoodSupportsHIGH confidence
the proportion of free leptin is increased in serum of obese subjects... apparent leptin resistance in the setting of increased free leptin.
Gema Frühbeck et al. · Clinical Physiology · 1998

Why this rating

Supported by multiple human studies cited regarding serum levels in lean vs obese subjects.

Source

Leptin: physiology and pathophysiology

Gema Frühbeck et al. · Clinical Physiology · 1998

DOI 10.1046/j.1365-2281.1998.00129.x

narrative_reviewCited 254×
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DOI resolved against Crossref · corpus check 2026-06-10

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