For the past several months I've been wearing bindis. At first I only wore them on special occasions with formal attire. Today I wear them everyday for reasons that I'll reveal upon request but enough about me.
The bindi is arguably the most visually fascinating of all forms of body decoration.
Today, bindi is more of a fashion statement than anything else, and the number of women sporting bindis is overwhelming even in the West.
Again, according to Wikipedia - Henna or Hina (Lawsonia inermis, syn. L. alba) is a flowering plant, the sole species in the genus Lawsonia in the family Lythraceae. The word "henna" (حــنــا) comes from the Arabic name for the plant, pronounced /ħinnaːʔ/ or colloquially /ħinna/.. It is also an islamic name given to girls which means blessed.
Some pastes have been found to include: silver nitrate, carmine, pyrogallol, disperse orange dye, and chromium. These have been found to cause allergic reactions, chronic inflammatory reactions, or late-onset allergic reactions to hairdressing products and textile dyes.
Henna itself is used for many things such as hair treatment, heat rash relief, and skin conditioner to name a few. The top leaves of the plant are best for mehndi, while the lower part of the plant is used for the other purposes. Henna paste is what is made to apply henna art designs.