Since y'all are beauty blog readers, you probably already know that the "No Poo" movement has nothing to do with constipation, despite how it might sound. It's a movement towards elimination of shampoo from your routine. There is a huge hodgepodge of methods currently in use, but the two most common are 1. using baking soda and apple cider vinegar and 2. Conditioner-Only washing (aka CO-washing). For the purposes of this post, I'm going to focus on the latter method.
|Image Source: https://www.flickr.com/photos/beglendc/|
Why Would One Want to Do Such a Thing?
I think that a big part of the reason that I've been asked to 'debunk' "No Poo" is because a lot of people are motivated to cut out shampoo for reasons that are not empirically supported. A lot of people are under the impression that there is something "dangerous" about shampoo, which is simply contrary to the scientific evidence.
With that said, there are still valid reasons to be interested in reducing or eliminating shampoo use.
Firstly, many people find the shampoos can be harsh and damaging. Like any soap, surfactants are comprised of a lipophilic (oil-attracting) side and a hydrophilic (water attracting) side. The lipophilic side glomps onto the oil in your hair and traps it in a sphere called a micelle. Afterwards, you can happily wash it out. (I have a lengthier discussion of soap mechanisms available here, if you want more info.)
|Sodium Laureth Sulfate (SLES) is a surfactant. Because one side is polar, it is hydrophilic, whereas the long, non-polar chain is lipophilic.|
Image source: http://en.wikipedia.org/wiki/File:Sodium_laureth_sulfate_structure.png
Shampoo surfactants are really good at this. They get your hair squeaky clean. However, they can definitely be hard on your hair. In the International Journal of Trichology, Zoe Draelos (2010) notes, "Many persons feel that they do not have good hygiene unless they bathe daily. Technically, it is not necessary to shampoo the hair daily unless sebum production is high. Shampooing is actually more damaging to the hair shaft than beneficial." Any time you get your hair wet, you're causing some damage, but the surfactants in shampoo are certainly harsher than water alone.
Thus, many people want to avoid traditional shampoos to help minimize the damage they are causing to their hair.
|Basic shampoo ingredients|
The second big reason to avoid shampoo is because it is expensive. As many of you already know, I have a shitload of long hair. I am not "No Poo", but I personally do not wash my hair on the daily simply because I don't want to spend a gazillion dollars on shampoo.
Does It Work?
Shampoos typically contain anionic surfactants like Sodium Laureth Sulfate or Ammonium Lauryl Sulfate. (High school chemistry reminder: an ion is a molecule with a charge; an anion is a molecule or atom with a negative charge.) They are anionic because the polar, hydrophilic group is negatively charged. They are super awesome at removing sebum and other yucky shit in your hair, which is the point of shampoo.
Still, conditioners frequently also have surfactants. Usually, they are cationic surfactants, like Cetrimonium Chloride or Distearyldimonium Chloride. Since a cation is a molecule or atom with a positive charge, you've probably already guessed that cationic surfactants have a positively charged polar group. Cationic surfactants are awesome at leaving your hair silky smooth, but they are not as effective at removing sebum, so they aren't used in most shampoo. When they are found in shampoo, it's usually shampoo that's specifically designed to be as gentle as a snuggling guinea pig.
Image Source: http://en.wikipedia.org/wiki/File:Cetrimonium_chloride.png
Additionally, people who go the CO-washing method frequently run into trouble when they use a ton of other hair products. In particular, silicones tend to be really difficult to remove, and could build up in your hair until you finally break out the shampoo.
Should I Try It?
Ultimately, it's up to you to decide whether CO-washing is a good idea for your hair. If you like it, I suspect that you'll feel your hair is softer and less damaged and/or that you're spending less money on haircare products. If you hate it, my guess is that you'll feel your hair is dirty and weighed down, and/or that it's too much trouble to find products that work without shampoo to lend a helping hand.