Hi everyone! This video is going to be part review, part science.
So we're going to be talking about Henna. This is my first experience ever
using a natural hair dye. Made with henna, henna is a plant so the leaves are
dried and powdered. So I got my henna from Lush and this comes in a big block
so the henna has been pre-mixed with some lemon juice and some cocoa butter and
some other kind of oils and things. The first thing you need to do is to break
up the henna into small pieces
some people recommend grating it but I thought that would take too long so I
went for a more elegant option of just bashing it with a rolling pin and it
seemed to work pretty well in retrospect I would have tried to break up the larger
pieces even smaller. Then place the broken up henna into a heat-proof bowl.
Then you put heat-proof bowl over some boiling water to melt the henna
so make sure you give it a good stir as its melting. You also need to add some
boiling water to the henna itself
I only did this a little bit at a time because you don't want to make the
henna too runny because there isn't
you know there's no going back from that really. The final consistency should be
yogurt-like. In the instructions it says like thick hot chocolate, but I didn't really know
they meant by that. When you apply this just make sure you wear gloves
otherwise you will stain your fingers. Then you just got to be prepared to make
a mess so you can see when it goes on the hair kind of turns dry and mud-like
and I'm not going to say what this looks like because I think we all know
"A worthless, steaming pile of cow-dung, figuratively speaking!' (No copyright infringement intended. Educational purpose only)
And after washing out you can now see my mousey-brown hair is auburn!
The application of it was not as bad as a lot of the reviews seem to make it out to be.
Yes it was like trying to put mud on your hair and it did drip places it was
kind of a little bit awkward and the smell isn't too bad a lot of people seem
to complain about the over-the-top earthy
smell. It does have a unique scent but it's by no means overpowering and it
does kind of stick around in your hair for a day or so but it's definitely
not going to ever put me off using it again. To understand how henna works and
how chemical dyes work you have to understand the structure of hair
so the very outer most layer is known as the cuticle and this is made up of
overlapping cells so it kind of makes a scaley
appearance and the function of the cuticle is protect the underlying cortex
the cortex is where you'll find the natural pigments of your hair, so the
melanin that actually gives your hair its color
you might also have an innermost layer which is known as the medulla but not
all people have this and the role of the medulla isn't actually really known.
So the way chemical dyes work is they actually have to disrupt the protective
layer of your hair in order for the dye to penetrate. Components of a chemical dye
such as ammonia act to lift up those scales of the cuticle to allow dyes and
other chemicals to penetrate.
Now the chemicals that get inside include peroxide and what peroxide does is it
breaks down the natural hair pigment so that it can be replaced with the chemical
dye. Repeated dying your hair with chemical dyes can lead to that cuticle layer
becoming a irreparably damaged and no matter what all these shampoos and
conditioners and special leave-in treatments might say, once that cuticle
has gone past the point of no return
all these shampoos and products can do is give the appearance of healthy hair
but the underlying hair will still be ******
But how does henna actually work?
I bought my henna up from lush which most of you know they sell henna in these kind
of big chocolate bar-looking blocks. And if we go on their website they state
that unlike chemical dyes henna works on the cuticle and acts like a varnish.
So this doesn't really tell you anything about how henna actually interacts with
the hair and something that just coats the outside of hair you wouldn't think
would have very long staying power so you think it'd be something that washes
out quite quickly.
Now if we go to this website this is known as mehandi.com they have loads
information about henna
but if we actually look at information provided on one page it says that lawsone
gradually migrates from henna into the hair shaft and binds with keratin
Wait a second! I thought we were talking about henna what's lawsone? Lawsone is a
red orange dye molecule found in henna. It undergoes a strong chemical reaction
with keratin which is a protein found in hair resulting in a strong permanent
stain. Another part of the website states lawsone does not coat the hair
it binds into the keratin scales that make up the outside layer of hair
Now they also link to a blog post which again doesn't seem to have any kind of
scientific references to research papers where they actually found this information.
It states lawsone a relatively small molecule then migrates into the cortex
of the hair strand to coat keratin. So now we're saying it actually goes past the cuticle into the
cortex to interact with the keratin that's found there. They also
state that the sensation of dryness that follows lemon juice application is not
hair damage but the scales of keratin being raised to bind with the lawsone.
So what's the truth? Does the lawsone penetrate into the cortex? Does it just coat the
outer layer of hair? Does it somehow interact with the keratin scales of the cuticle?
Well if we look at the scientific literature, from all my researching I
was only able to find very vague references to how henna actually works such
as penetrates the hair shaft or penetrate skin and diffuse into hair.
One said that lawsone gradually migrates from the paste into the outer layer of skin
or hair, but no one source seems to state definitively how henna actually works.
So I contacted Lush and whilst their customer service representative was
absolutely wonderful she couldn't actually give me any further information about
how henna works or where they got their information from. I also contacted mehandi.com
but unfortunately didn't even receive a reply from them.
What we do know is that lawsone requires an acidic environment in order
to react with keratin which is probably why we find lemon juice in the henna
block. And then the lawsone, because it's a small molecule, can either then
interact with the keratin just in the outer cuticle or perhaps even migrate into the
cortex as well.
Now what's interesting about henna is you actually retain your natural hair
pigments as well as the added red dye pigment from the henna
so instead of your natural pigments be destroyed and replaced by the dye you
actually have both so the color you get is unique to your own hair.
But the big question is: is henna even safe to use? The most recent safety
report actually says that henna is safe for use as a hair dye provided the
concentration of lawsone is no higher than 1.4%.
Studies have shown that it shows no evidence of skin sensitisation, mutagenesis
which is a mutation of DNA or genotoxicity which is the components
causing damage to DNA.
What they did find was that lawsone could have some clastogenic properties that
means it could cause aberrations of chromosomes, but further studies found
that the experimental conditions used were not applicable to the consumer. So the
conclusions of the studies is that henna is safe to use as a hair dye.
Now that being said there are a lot of different hennas you can find in the shops and
not all hennas are created equal, some might have metallic salts or sneaky
chemical dyes in there
so if you are going to go for a natural hair dye if you want to try henna make
sure you getting one that is from a reputable source that is a hundred
percent natural
I purchased my henna from Lush and it's reported as being a hundred percent
natural so you know there's no nasty bits in there and it comes as a block of
six cubes and that cost me about £9.75 I think, and it took about three blocks for my
hair really needed right three and a half
so you get maybe one, one and a half uses out those six blocks. My hair is quite short so
you can imagine if you've got long hair it might be quite expensive for you to use henna
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