Sh-Polypeptide-4

Sh-Polypeptide-4 is a synthetic peptide — a short chain of amino acids — designed to mimic naturally occurring protein structures in skin. It functions as both an antioxidant and a skin conditioning agent, meaning it can help neutralise free radicals and improve the texture and feel of the skin barrier.As a peptide ingredient, it works at a molecular level to support skin's own protective mechanisms. Peptides are favoured in skincare because they are small enough to interact with skin cells whilst remaining stable in cosmetic formulations.

Sh-Polypeptide-4 operates through two primary mechanisms. As an antioxidant, it helps neutralise free radicals — unstable molecules that damage skin cells and accelerate ageing. By reducing oxidative stress, it may help preserve skin resilience and appearance over time.As a conditioning agent, the peptide forms a protective film on the skin surface, reducing water loss and enhancing smoothness. This dual action makes it a versatile addition to serums, moisturisers, and targeted treatments.

Sh-Polypeptide-4 is generally well-suited to serums and lightweight moisturisers. Apply to cleansed skin before heavier creams. It can be layered with other actives, though combining multiple antioxidants is unnecessary unless you have specific concerns. Consistency is more important than concentration when assessing peptide benefits — use daily for best results.

Sh-Polypeptide-4 is generally well-tolerated across skin types. As a synthetic peptide, it carries minimal sensitising potential, though patch testing is advisable if you have reactive or very sensitive skin.