
Henna refers to a shrub known as Lawsonia Inermis which
predominantly grows in the hot climates of Northern Africa, the
Middle East, and Asia. Its leaves, which produce a red dye, are
harvested, dried, and then ground into a fine powder. Henna
powder is traditionally used in these regions to dye the hair and to
decorate the body, an art referred to as mehndi or simply, henna.
This plant has been used for thousands of years not only for
decorating the body but also for its medicinal properties. Henna has
a cooling effect and is a natural sunblock. For this reason it was
widely used in these regions where the climate is very hot.
Additionally, it was believed to have protective qualities that
warded off "evil spirits". Mehndi is still practiced today throughout
these cultures for special ceremonies such as marriage and spiritual
celebrations.
For use in mehndi, the powder is mixed with lemon, sugar, and
essential oils to form a paste which is then applied to the skin. The
method in which it is applied varies from region to region. For
example, in India, the preferred method uses a cone applicator while
in Morocco, a syringe filled with henna paste is preferred.
Henna stains the top layer of the skin a reddish-brown color
typically lasting between one and three weeks. Natural henna is
always an earthy color and produces earthy-colored stains, it is
never black. "Black henna" is not natural and can be dangerous.
"Black henna" contains PPD (para-phenylenediamine) which is
used in synthetic black hair dye and can produce very serious
allergic reactions.