Peptides vs proteins
The line between peptide and protein is mostly about length and folding.
Both peptides and proteins are chains of amino acids linked by peptide bonds. The distinction is one of degree: peptides are short and often unstructured, while proteins are long and fold into defined three-dimensional shapes that carry out complex functions.
This matters for delivery. Larger, folded proteins are even harder to dose orally than peptides, and both are typically administered by injection in research and clinical settings because the digestive system breaks them down.
Educational and research reference only. Not medical advice.