Carrie’s curious: First, I must say your site is amazing. I’ve been looking for years for an evidence- and research-based beauty site. Brilliant. I’d like to know more about henna. You mention it very briefly in the
article about “organic” hair dyes but you don’t go much further than that. Can one of “The Brains” do a feature on henna, and any other plant-derived dyes (if there are any) out there?
The Right Brain’s response:
Ask, Carrie, and you shall receive. We found a great resource for henna information, and it’s heavily annotated with references. We’ll paraphrase some of the key information here to answer your question, but we recommend checking out the site for more details.
What is henna
Henna is a shrub (Lawsonia Inermis ) whose leaves contain a tannin dye molecule known as Lawsone. Lawsone is released when the leaves are pulverized, acidified and made into a paste. This paste can be applied to hair or skin to give it a deep, reddish brown stain.
What colors does henna come in?
Despite what you might have heard there is no such thing as black or blonde henna. True henna ONLY comes in reddish brown. Any black or blonde hair dyes that claim to be henna are mixing henna with other materials that could be either other plant dyes or synthetic chemicals.
Can I use henna instead of permanent hair colors?
Using real henna creates a dark stain will provide long lasting color. However, as noted above, you’re limited to a single color pallet. Also, it won’t bleach color out of your hair.
Is henna bad for my hair?
No, real henna is not damaging, since it only stains the keratin protein in your hair. But some of the compounded hair dyes use oxidative and metallic compounds which can be damaging to your hair.
Are there other natural hair dyes that give different colors?
There are other natural dyes that can stain hair but remember these won’t lift color. (Again, they won’t bleach your hair lighter.) Here are the colors of ten natural plant hair dyes listed by hair color. Click the reference links at the bottom for a full description of each.
- Henna: Lawsonia Inermis
- Walnut: Juglans regia
- Catechu: Acacia catechu
- Cassia obovata: also called “neutral henna”
- Catechu: Ourouparia gambir
- Saffron: Crocus sativus L.
- Chamomile: Anthemis nobilis
- Rhubarb Root: Rheum rhapoticum
- Vashma: partially fermented indigo
- Karchak: castor bean
- Indigo: Indigofera tinctoria
- Woad: Isatis tinctoria
The Beauty Brains bottom line
It’s cool how many natural hair dyes there are, even though they don’t work as well as the oxidative colors.