Glossary
Peptide
Also written peptides
A short chain of amino acids: the same building blocks as a protein, in a chain short enough to behave differently.
The line between a peptide and a protein is a convention, not a fact of chemistry, usually drawn somewhere around fifty amino acids. What follows from the length is real: short chains are digested if swallowed. Which is why almost everything here is injected.
Several compounds sold and discussed as peptides are not peptides at all. MK-677 and 5-Amino-1MQ are small molecules taken orally; they sit alongside peptides in the same shops and the same conversations, and their profiles here say so.
Being a peptide implies nothing about safety, evidence or legality. Insulin is a peptide; so is a compound with no human data at all.
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