Henna 101

What is henna?

Henna comes from the leaves of the Lawsonia inermis plant and is used to dye the hair and/or create henna body art. There are two types of henna you can choose from to dye your hair: body art quality (BAQ) and henna for hair. I've found that the best henna for me is the BAQ because: 1) BAQ is a much finer sift so it doesn't leave any gritty residue in my thick, dense hair and 2) BAQ has a higher dye uptake which yields a richer color that is permanent when the BAQ henna powder is mixed with an acidic liquid such as green tea. 

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Even after I started using henna I was confused by all the 'henna' products out there. It wasn't until I began researching for this post that I fully understood the difference between real henna and its impostors. Real henna (Lawsonia inermis) leaves a reddish-orange tint (the results vary based on your natural hair color). If you're a brunette then henna will not turn your hair bright red but rather it will combine with your color and add a reddish-orange tint. 'Neutral Henna' is not actually henna but Cassia obovata (or Cassia for short). Cassia has other benefits that I'm not going to cover in this post. 'Black Henna' isn't henna either but is actually Indigo. The confusion between the three may arise from the fact that A) in powder form they all appear greenish in color and B) there are products that claim to be "henna" but actually are not pure henna. According to Henna for Hair, a trusted henna info source:

Some Blonde, Brown, Auburn, Mahogany, and other “shades” of henna are mixes of amla, indigo, walnut, rhubarb, and Lawsonia, with other plant or synthetic dyes added, and may have metallic salts added. Many of these products have no henna whatsoever and are chemical dyes. Some commercial brands that claim to be 100% natural may include a bottle of “developer”; beware!  This is a completely bogus addition, as far as henna itself is concerned and is the biggest indicator that your product is NOT even close to being 100% pure henna!  The labeling on these products is often misleading, inaccurate, false, or entirely missing.  The quality is often very poor.

Why do you use henna?  

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Henna is an excellent conditioner for the hair. Lawsone, the red-orange dye molecule, penetrates the shingle-like cuticle layer of the hair shaft and bonds to the keratin in the cortex or middle layer of the hair strand. This strengthens the hair strand much like a protein treatment. Since the color of our hair is determined by the color found in the cortex, the lawsone molecule acts as a red-orange tint and combines with your natural hair color. With repeated applications henna will make your color deeper and richer. For example, I've been using henna for several months now and as a result my hair is a deep, rich burgundy in the light. When I'm not in bright light I think it appears to be reddish-brown.

Henna has also been known to loosen the natural curl pattern when used repeatedly. I love henna for this reason because my thick, dense, pencil-diameter coils and curls can be difficult to manage. If your curls are already loose you may want to choose Cassia over henna as Cassia has the same conditioning properties as henna but without the curl-loosening effect. 

My hennaed hair. You'll notice that the portion of my hair
that's in the shade appears darker, while the portion in
the sunlight has a reddish tint.