Henna and Other Natural Dyes
Henna works much like other dyes, depositing color on and underneath thecuticle, but the cuticle is opened by heat rather than by chemicals. Pure henna results in a red orange shade; henna products that color hair in the brown range contain other dyes, either plant based or not. It used to be all the rage, but henna has fallen out of favor in recent years. This is probably a good thing, because it can be quite drying and builds up fairly quickly -- the longer you use it, the brassier and coarser your hair will become. Plus, you'll probably get better color results from a regular product. If you use henna, don't put other colorants on your hair until you've washed it several times -- otherwise, you risk an uneven look. That said, colorless henna shampoo can help add volume to fine hair; just don't use it too often or the residue will weigh it down.
Chamomile is sometimes added to shampoos and conditioners for blonde and light brown hair and, over time, can help to lighten and brighten it slightly without damage. Walnut is used occasionally to enrich the look of dark hair.
