Research

Hormonal

Ghrelin is an endogenous peptide hormone that stimulates food intake and growth hormone secretion, with its circulating levels inversely correlated with energy balance (increasing during fasting/starvation and decreasing during feeding/obesity).

Understand that hunger is biologically regulated by ghrelin, which rises when you are fasting or have low energy stores and falls after eating. In obesity, this system is often blunted, with lower baseline ghrelin levels, which may contribute to the difficulty in regulating food intake. Recognizing this hormonal drive can help separate biological hunger from emotional or habitual eating.

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Ghrelin, identified as an endogenous ligand for the growth hormone secretagogue receptor, functions as a somatotrophic and orexigenic signal from the stomach... The secretion of ghrelin increases under conditions of negative energy-balance, such as starvation, cachexia, and anorexia nervosa, whereas its expression decreases under conditions of positive energy-balance such as feeding, hyperglycemia, and obesity.
Hiroshi Hosoda et al. · Journal of Pharmacological Sciences · 2006

Why this rating

This is a comprehensive review by the discoverers of ghrelin, citing numerous primary studies, but it summarizes existing data rather than presenting new primary clinical trial data.

Source

Biological, Physiological, and Pharmacological Aspects of Ghrelin

Hiroshi Hosoda et al. · Journal of Pharmacological Sciences · 2006

DOI 10.1254/jphs.crj06002x

narrative_reviewCited 203×
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DOI resolved against Crossref · corpus check 2026-06-10

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