Silk protein, particularly in the form of hydrolyzed silk or silk fibroin, is increasingly used in skin care products for its purported moisturizing and barrier-enhancing properties. Scientific studies indicate that silk proteins can form a protective film on the skin, helping to reduce transepidermal water loss and improve skin hydration. For example, research published in peer-reviewed journals has demonstrated that silk fibroin can enhance the moisture-retaining ability of the skin and may contribute to smoother skin texture. Additionally, silk proteins are rich in amino acids, which may support skin repair and regeneration processes.

However, while laboratory and small-scale clinical studies provide some support for these effects, the overall quality and quantity of evidence remain limited. Most of the available data are derived from in vitro studies or small human trials, and there is a lack of large, high-quality randomized controlled trials directly comparing silk protein with other established moisturizing agents. Furthermore, the benefits appear to be modest and primarily related to skin hydration rather than treatment of specific skin diseases. Thus, while there is a scientific rationale for using silk protein in general skin care, the evidence is not robust enough to strongly recommend it over other well-established ingredients.