Research

Hormonal

Obese humans exhibit resistance to the effects of endogenous leptin, as high plasma leptin levels associated with large adipose mass fail to trigger the expected reduction in food intake or increase in energy expenditure.

Obesity is not caused by a lack of leptin; in fact, obese individuals typically have high levels of this hormone. The issue is 'leptin resistance,' where the brain fails to respond to the signal to stop eating. This suggests that simply having more leptin won't work; the focus must be on improving the body's sensitivity to these signals through lifestyle changes.

GoodQualifiesHIGH confidence
With the exception of a few very rare cases, the majority of obese human subjects have high plasma leptin levels that are related to the size of their adipose tissue mass. However, the expected regulatory responses (reduction in food intake and increase in energy expenditure) are not observed in obese individuals.
Eric Jéquier et al. · Physiological Reviews · 1999

Why this rating

Based on consistent findings of high leptin levels in obese humans without corresponding regulatory response.

Source

Regulation of Body Weight in Humans

Eric Jéquier et al. · Physiological Reviews · 1999

DOI 10.1152/physrev.1999.79.2.451

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

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