How is henna hair dye different from regular chemical dye, and what result should I realistically expect? — Iranian natural henna, 25 g

Henna works in a fundamentally different way from ammonia-based or oxidative hair dyes. Chemical dyes typically penetrate the hair shaft to remove your natural pigment and deposit new color. In contrast, this pure henna powder contains finely milled Lawsonia inermis leaf. When mixed with hot water, its color molecules are released and form a translucent, physical coating on the outer layer of your hair. This means it doesn't bleach or alter your underlying pigment.

Your realistic result depends strongly on your starting shade. On light or grey hair, henna can produce bright, coppery-red or warm chestnut tones. On medium to dark brown or black hair, it usually adds a warm tint or reflective glow that's most visible in sunlight, giving hair a richer, denser appearance. Because it's a coating, it can also make hair look smoother and more glossy, especially if your strands are porous or dull. It will not cover white hair as opaquely as synthetic dye, but will tint it. For predictable results, always do a strand test on a small, hidden section first.