Research

Hormonal

Fasting plasma ghrelin concentrations are negatively correlated with body mass index (BMI), with lower levels in obesity and higher levels in anorexia nervosa, indicating that chronic positive energy balance suppresses ghrelin secretion.

Your body's hunger hormone (ghrelin) levels are biologically tuned to your long-term weight status. In obesity, baseline ghrelin is suppressed, which may contribute to the difficulty in losing weight or maintaining loss, as the hormonal drive to eat is chronically altered. This is a physiological adaptation, not a failure of willpower.

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Fasting plasma ghrelin concentration was negatively correlated with body mass index in both nondiabetic and diabetic patients... Plasma ghrelin concentrations in patients with simple obesity and anorexia nervosa were lower and higher, respectively, than those of healthy subjects with normal body weight.
Tomomi Shiiya et al. · The Journal of Clinical Endocrinology & Metabolism · 2002

Source

Plasma Ghrelin Levels in Lean and Obese Humans and the Effect of Glucose on Ghrelin Secretion

Tomomi Shiiya et al. · The Journal of Clinical Endocrinology & Metabolism · 2002

DOI 10.1210/jcem.87.1.8129

cross_sectional · n=98Cited 1,265×
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DOI resolved against Crossref · corpus check 2026-06-10

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