Stomach-derived hunger signal that also amplifies GH pulses. Structurally it is Acylated peptide hormone (28 aa).

How strong is the evidence for Ghrelin?

PeptideHormone grades Ghrelin at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.

What is the half-life of Ghrelin?

The reported circulating half-life of Ghrelin is ~30 min (acyl-ghrelin).

Ghrelin

Stomach-derived hunger signal that also amplifies GH pulses.

EndogenousEstablishedCompare lineage

The only well-established hormone that makes you hungry rather than full — the counterweight that keeps appetite a balance.

Identity

Class: Acylated peptide hormone (28 aa)
Source: Stomach (X/A-like cells)
Receptor: Growth hormone secretagogue receptor (GHS-R1a)

Key properties

Evidence floorClinicalREF1CLIN1

Molecular weight

~3,370.9 Da

REF

Half-life (native)

~30 min (acyl-ghrelin)

CLIN

Model dosing

Approximate values for the native hormone; engineered analogs are often deliberately larger and far longer-acting. Each figure carries its own provenance tier, and the floor is the weakest of them - the Standard.

Mechanism

Ghrelin acts at GHS-R1a — a different receptor from GHRH — to amplify GH secretion, and centrally to drive appetite. Its activity depends on a unique acyl modification, making the acylating enzyme GOAT part of its biology.

Reference notes

Ghrelin is the endogenous ligand for the receptor that synthetic GH secretagogues (GHRPs) target.
It is one of the few clearly orexigenic (hunger-promoting) circulating hormones.
Its acyl modification is required for GHS-R1a activity — an unusual structural requirement.

Common questions

What is Ghrelin?: Stomach-derived hunger signal that also amplifies GH pulses. Structurally it is Acylated peptide hormone (28 aa).
How does Ghrelin work?: Ghrelin acts at GHS-R1a — a different receptor from GHRH — to amplify GH secretion, and centrally to drive appetite. Its activity depends on a unique acyl modification, making the acylating enzyme GOAT part of its biology.
How strong is the evidence for Ghrelin?: PeptideHormone grades Ghrelin at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.
What is the half-life of Ghrelin?: The reported circulating half-life of Ghrelin is ~30 min (acyl-ghrelin).

Selected literature

Curated peer-reviewed reviews, sourced from PubMed. Selected for relevance, not exhaustive — open any entry on PubMed for the full record and its primary citations.

1.The Homeostatic Force of Ghrelin · Cell metabolism, 2018 · PMID 29576534
2.The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review · Obesity reviews : an official journal of the International Association for the Study of Obesity, 2007 · PMID 17212793

External references

Ghrelin in the public knowledge graph — the same entity resolved across the authoritative chemistry and protein databases.