Thursday, June 3, 2010

Chemistry of your hair: Fine hair

What makes fine hair different than average or coarse hair? Fine hair tends to lack firmness and rigidity, is susceptible to fly-aways, is hard to style, and tangles easily. Why is that?

Our hair is made up of three layers - the medulla, the cortex, and the cuticle. The medulla is the important part when it comes to fine hair. The medulla is found only in the terminal hair on our bodies, and it is located in the middle of the hair shaft. It is composed of a protein called trichohyalin, and the degradation and metabolism of this protein contributes to the water holding properties of our hair.

Fine hair has a smaller diameter than average (fine hair is less than 60 µm, average 60 to 80µm, and thick more than 80 µm), so as you can expect, the ratios of the three hair layers will be different. In thick hair, the cuticle might make up 10% of the hair strand with 90% being the cortex; in fine hair, the cuticle might make up 40% of the hair strand with 60% being the cortex. Some fine hair is so fine it might not even have a medulla (but that has to be less than 40µm in diameter, and that's pretty much vellus or body hair). Even if you do have a medulla, it will be smaller than those found in other hair types. Which means you aren't getting the wonderful benefits of the proteins, which help to contain moisture in your hair! And because your cortex is smaller, your hair is not as strong as hair containing more cortex - like coarse hair!

Because fine hair contains more cuticle than other hair types, you have more cuticle scales that want to repel each other, creating more static and more fly-aways. You are also more prone to breakages, split ends, and damage through grooming, styling, and daily life. Sebum also spreads very quickly through fine hair, so woe betide the girl with fine, greasy hair! You want to shampoo daily because of the sebum, but you don't want the damage!

What is a fine haired person to do?

You want to use daily use shampoo levels of surfactants even if you aren't washing every day. You want to use light conditioners that prevent static build up, which leads to fly-aways. Cationic polymers don't tend to be your friend - they can build up quickly on fine hair and weigh it down, so conditioning shampoos are probably not the best option.

My suggestion not to use cationic polymers only applies to using them in shampoos. You can make some awesome conditioners and detanglers using cationic polymers like polyquat 7 or honeyquat. Check out this post for more information! 

Cationic quaternary compounds can be your friend - cetrimonium chloride is awesome for fine hair, and light conditioners filled with proteins are a great choice. Don't not condition! They will cause the fibres in your hair to lay down in a parallel arrangement, which makes hair more manageable!


Tara said...

I want to use cetac and cetab in my conditioner for my fine hair. Should I use BTMS or Incroquat CR with them?

Susan Barclay-Nichols said...

Hi Tara. I'd try cetab and cetac first and see how you like them together. If you feel you want a little more lubrication, then add a titch of BTMS. If you want a bit more softening or anti-static, then add the Incroquat CR. The cetab is a great conditioning agent, and the cetac will help with detangling and both wet and dry combing.

Let us know how it turns out!

WP said...

Love your posts. It's great to read this from a scientific level, because I have fine CURLY hair, and I often get mixed signals about needing plenty of moisture(oils and humectants), vs. using only light emollients etc. I'm currently trying to make my own conditioner(leave-ins, etc) to tailor them to my specific needs. I just can't seem to get the moisture balance right. Do you know of any books that talk about this stuff giving the best products to use on this type of hair ie: BTMS versus cetrimonium chloride, or using lighter oils like almond oil versus coconut? Thanks

Anonymous said...

Hi Susan,I have a very fine and straight hair without body.I have problem with combing and statics and my hair does not have any volume, so you can imagine how it looks like.I have not been able to find any recipe that suits my hair in your blog.Have you got any solution for my problem.By the way I don't have access to Incroquat CR.Is there any alternative. Thanks a lot

Susan Barclay-Nichols said...

Hi WP! Have you looked much of this blog? I ask because I go into great detail about BTMS and cetrimonium chloride and other conditioning products, and I have an entire section on oils. If you click here, you can see more of what the blog has to offer. If you're interested in a book on the topic, there really isn't anything out there unless you want to get into $100 to $300 textbooks (and I can recommend a few of those). I do have an e-book available (look to the right hand side of this page).

Hi Anonymous. If you visit the hair care part of the blog, you'll see some recipes for detanglers and cream rinses - those would be a good choice for your hair type. I'm not sure what to suggest if you don't have Incroquat CR as this is a good conditioner for your hair type. I'd suggest taking a look at what various conditioners are available to us homecrafters - again, go to the hair care part of the blog or look at the right hand side of the page for ingredients - to see what you can access and what would work for you.

Barbie Beach said...

Has anyone ever done researched/ broken down the recipe for "Color Vive" Regular product by Loreal now discontinued? It was the best conditioner EVER that I used for years on my SUPER FINE WAVY HAIR. Not only was it a great weightless conditioner it was wonderful for tangle free hair. I would love to duplicate this product!

Nichole Zimmermann said...

I have no madula in my hair. I tried to have it professional die job and my hair will not die at all. I have never diedone my hair up until a few weeks ago. Both times I spent the money at a salon and my hair is the same color when I walk out as when I walked in. She has even tried different dyes.

Anonymous said...

My hair was coarse and healthy until my last child was born. Now is it super fine with no tensile strength. I wouldn't dare color or perm it. I am wondering if there is any way to make fine hair course again. I use Loreal sulfate free thickening shampoo and conditioner and it helps the appearance of volume, but I'd rather actually have the volume if that's possible. Thanks!