I peptides are short chains of amino acids, generally comprising two to fifty units: longer than a single amino acid, but much shorter than a protein. They are not a single ingredient but a category, and they are the area in which cosmetic research has produced the most significant innovations in recent years.
They are divided by function. Signal peptides tell fibroblasts to produce collagen, mimicking the fragments generated by the dermis as it breaks down. Neuromodulators reduce the intensity of facial muscle contractions. Carrier peptides transport trace elements such as copper where they are needed. Enzyme inhibitors slow down the enzymes that break down collagen and elastin. The INCI name indicates which group each one belongs to, and learning to read it changes how you choose a product.
The result therefore depends on the group: firmness and density for signal peptides, expression lines for neuromodulators, and the eye area for those with a draining action. They are almost always formulated in serum, because its lightweight texture encourages contact with the skin, and they are applied before cream. The time frame is similar for all of them: six to eight weeks of consistent use.
There is one purchasing criterion that matters more than many others: the generic wording “with peptides” does not say which one, whereas a label that lists the peptide by name — Acetyl Hexapeptide-8, Palmitoyl Tripeptide-1, Acetyl Tetrapeptide-5 — lets you know exactly what you are investing in. It is the first check to make when looking at an anti-aging serum.
On our blog, you can find an in-depth look at what peptides are in cosmetics and how to choose them.
