Fibroin

Fibroin is a naturally occurring protein extracted from silk fibres, typically sourced from silkworm cocoons. In skincare formulations, it serves primarily as a bulking agent that helps create structure and texture in products whilst offering film-forming properties on the skin's surface.The protein is biocompatible and biodegradable, meaning it integrates well with skin tissue and breaks down naturally over time. This makes it a popular choice in both conventional skincare and advanced skin repair applications.

Fibroin works through multiple mechanisms. As a film-former, it creates a permeable layer across the skin that helps reduce transepidermal water loss without occluding pores. The protein's structure allows it to interact gently with the skin barrier rather than sitting passively on the surface.In more advanced formulations—such as hydrogels or wound-care products—fibroin can be engineered to release bioactive compounds gradually and support the skin's natural repair processes. The protein's biocompatibility means it integrates with skin tissue with minimal disruption.

Fibroin is typically present in products formulated to maximise its texture and film-forming benefits, such as serums, hydrogels, and masks. Apply to clean, dry or damp skin as part of your regular routine. It works well layered with other hydrating ingredients but is not essential for effective skincare.

Fibroin is generally well-tolerated and suitable for sensitive skin. Those with silk allergies should exercise caution, though allergic reactions to silk fibroin in cosmetics are rare.