What Are Peptides?
Peptides are short chains of amino acids — the building blocks of proteins. Here's everything you need to know.
The Basics
Peptides are molecules made up of 2 to 50 amino acids linked together in a chain. They are smaller than proteins (which are longer chains) but work in a similar way — binding to receptors and triggering specific biological responses.
Your body naturally produces hundreds of peptides to regulate everything from hunger and metabolism to sleep, mood, tissue repair, and hormone release. Synthetic peptides mimic or enhance these natural signals.
Unlike anabolic steroids, most peptides work by stimulating your body's own production of hormones or natural repair processes — rather than replacing them directly.
How Peptides Work
Receptor Binding: Peptides bind to specific receptors on cell surfaces, like a key in a lock. Each peptide targets a specific receptor type, causing a precise biological effect.
Signaling Cascades: Once a peptide binds to its receptor, it triggers a cascade of cellular signals. For example, GLP-1 agonists signal the brain to suppress appetite and signal the pancreas to release insulin.
Targeted Effects: Because peptides work through specific receptors, they tend to have targeted effects with fewer systemic side effects than many traditional medications.
Peptide Categories
Weight Loss (GLP-1 Agonists)
| Peptide | Receptors | Avg Weight Loss |
|---|---|---|
| Retatrutide | GLP-1, GIP, Glucagon (3) | 28.7% |
| Tirzepatide | GLP-1, GIP (2) | 22.5% |
| Semaglutide | GLP-1 (1) | 15% |