The way brow henna works on the hair and skin structure is unique in comparison to tinting. Tinting uses an oxidant to open the cuticle of the hair and penetrate the hairs through the oxidation process. Henna on the other hand, provides a coating to the hair shaft, coating the top layers of the hair cuticle only. As a result  eyebrow henna smooths out the hair, to give the appearance of a thicker, softer and smoother eyebrow hairs.