Do the added keratin, vitamin E, and linseed oil actually make a difference during colouring?

The three care ingredients work on the surface while the pigment deposits. Keratin fills microscopic gaps in the cuticle, helping the colour coat more uniformly and reducing the rough, straw-like feel that can follow intense pigment deposition. Vitamin E acts as an antioxidant that protects the hair lipids from oxidative stress during the colouring process and adds a light conditioning film. Linseed oil, rich in omega-3 fatty acids, lubricates the fibre and boosts gloss, which is especially useful for fashion shades that rely on light reflection to look vibrant. Together they make the application feel more like a treatment mask than a raw dye, but they do not rebuild broken disulfide bonds or reverse chemical damage — think of them as cosmetic support, not structural repair.