What effect does permanent colour have on the hair structure?

Permanent hair color alters the hair structure by penetrating the hair shaft and interacting with the natural pigments. The process typically involves opening the cuticle layer, which can weaken the hair and lead to potential damage or dryness. Additionally, the chemical reactions used to develop the color can strip moisture and alter the hair's natural texture. Over time, this can result in changes to the hair's overall health and appearance.