Henna is the Arabic name of the plant whose botanical name is Lawsonia inermis. It is a plant native to India but is also found in other Asian countries. Henna leaves contain an orange-red-brownish pigment. The leaves are dried and ground to make a dye that is used in hair colouring products, as well as in textiles and body art.
There are many stories about the origins of henna with its historical use noted in India, North Africa and various regions of the Middle East. References describe the use of henna in religious rites and festivals as far back as 9,000 years ago. Henna has historically been used to enhance beauty through use in skin drawings, colouring the hair and providing treatment to the scalp and to the strand of the hair.
Lawsone is a tannin that resides in the leaves of the henna plant when it has reached maturity. The leaves are collected, dried and triturated into a greenish powder. The chlorophyll in the leaves accounts for this hue.
True Henna, Lawsonia inermis, comes in only one colour, reddish brown. The shade or hue provided by the henna powder is determined by the age of the plant, growing region and the unique seasonal fingerprint that nature provides. The leaves from immature plants provide neutral henna, as the tannins are not yet present.
How does Henna work on the hair?
Lawsone’s natural dye has an affinity to the hair. It has the unique property of binding to the keratin scales of the cuticle, allowing the tannins to migrate into the outer layers of the strand. It acts as a sealant to the damaged parts of the hair strands, making them more uniform, thus allowing the strands to better reflect light. Henna remains on the hair for a considerable period of time (several weeks), but because it does not penetrate into the cortex of the strand, it is considered temporary hair colour.
Besides being a natural dye, henna offers other benefits. Historically, the plant has also been used by indigenous cultures to strengthen hair, reduce dandruff and hair fall. It is considered astringent and tonifies and exfoliates the scalp. Henna can also be instrumental in correcting oily scalp conditions.