Glossary · Pharmacology
Peptide
In short
A peptide is a short chain of amino acids, the building blocks of proteins — usually between two and around fifty. Many of the body’s hormones and messengers are peptides, as are some modern medicines.
The boundary with proteins is fluid; longer chains with a fixed three-dimensional structure are called proteins. Well-known peptides include insulin, oxytocin and the GLP-1 analogues now used against diabetes and obesity.
Peptides are mostly broken down in the digestive tract and are therefore often injected. In the biohacking scene, the term stands for a whole range of substances — from authorized medicines to compounds that have only been studied in animals and are available on the gray market.
“Endogenous” does not mean “harmless”: a peptide that the body makes in tiny amounts at a specific site can act quite differently in other amounts and in other places.
Peptide describes the structure — not the effect and not the legal status.
Where this comes up in the fact checks
- Semaglutide – An authorized peptide medicine with large outcome trials.
- BPC-157 – Three small human studies, none randomized, not an authorized medicine.
- GHK-Cu – An endogenous copper peptide made of three amino acids; the skin studies in humans are small.
- MOTS-c – A signalling peptide of 16 amino acids, encoded in mitochondrial DNA.
Sources
Related terms: Gray market · Bioavailability · Half-life · WADA list (Prohibited List)
Information only, not medical advice. The BK-Score is a subjective assessment according to disclosed rules – not a scientific evaluation. Scoring rules