Thursday, 27 February 2014

Can you really wash your hair with bentonite or rhassoul clay: A science experiment

After the previous experiment on co-washing, my fellow blogger and natural hair afficionado Milan suggested that I should do the same experiment with bentonite or rhassoul clay which are available on their own or as components in the popular mudwashes! Thank you Milan, because any excuse to break out my microscope is fantastic.

I promptly (literally the next day) purchased my clays from my local UK store Sheabutter Cottage (waves to the wonderful Akua!) and I finally got the results last night after a bit of bother with the microscope which needs a light bulb replacement, darn thing!

The Experiment
I used my own shed hair and imaged it:
-on its own without any washing
- washed with shampoo only (2 minute water rinse, 2 minute shampoo wash, 2 minute water rinse and air dried for 4 hours)
-washed with bentonite clay only ( 2 minute water rinse, 2 minute bentonite clay wash (pre-mixed clay with water), 2 minute water rinse and air dried for 4 hours)
-washed with rhassoul clay only ( 2 minute water rinse, 2 minute rhassoul clay wash (pre-mixed clay with water), 2 minute water rinse and air dried for 4 hours)

The Results

1. The Controls - Oily Hair and Shampooed Hair

I redid these two controls for this experiment because you always have to have a baseline of what the hair looks like prior to washing and what it looks like with a proper wash. You can therefore judge the clay washes in context of dirty and clean hair.

Unwashed hair - Oily hair for comparison

Shampooed Hair - Clean hair for comparison

2. Bentonite Clay Wash

Never having used bentonite clay, I was really surprised by how it felt, almost silky when you mix it into a paste. The cleanliness level was approximately the same as a co-wash with most of the oil layer removed and a few remnants still visible.

Bentonite clay washed hair  - Most of the oil is removed with some remnants indicated in the white circles

3. Rhassoul Clay Wash

Rhassoul did not really turn into a silky paste in the way bentonite clay did but it pretty much had a similar cleansing level. I would also rate the oil removal from hair by rhassoul clay as similar to a co-wash with most of the oil removed and some remnants visible.

Rhassoul clay washed hair - Most of the oil is removed but some remnants (white circle) remain

You can indeed clean your hair or to be specific, remove oil from your hair with bentonite or rhassoul clay and the level of removal is similar to co-washing!

Additional notes:
Running warm water was used for all washes. In each wash or rinse,  hair was rubbed gently to simulate normal hair washing. Hair conditioner - L'oreal Eversleek Smoothing Conditioner, Shampoo - Herbal Essences Dazzling Shine Shampoo.

Please do note that under the microscope we can see oil layers but we do not see small deposits on hair e.g hair conditioner deposits (well you actually could see them with specialised instruments but not with my microscope!). Strictly speaking this experiment will answer the question, how well will washing method X remove oil from hair.


  1. What's your hair type? I am 4 a/b fine coily low/pro hair. I am in the process of finding products that will penetrate my follicle and soften my hair. Looking forward to trying the clay.

  2. Thank you so much for doing this. I really love rhassoul clay cleansing and now I can feel more confident that it actually does the job but now I'll alternate between poo and mud.

  3. Interesting sis. Have you done it with ACV? Hope I didn't miss that one. I have bentonite clay but just feared build up. Maybe I mixed it up wrong. The thickness and 'gloopiness' made me never try it again.

  4. Great experiment! That helps me to decide which product to use to clarify monthly since its similar to a co-wash. Thanks. :)

  5. I love reading these just because I love seeing things under the microscope. Thanks for sharing :) this is very informative and I'm glad it's all nicely controlled and a neat little experiment

  6. I love your experiments.... you remind me of gabrielle duchess on youtube with your lovely experiments. I am officially sold and can now incorporate bentonite/rhassoul clay in my regimen

  7. Just thinking about this again, this may be a bit harder but I'd be interested to see if heat protectants actually help against the damage of flat irons?

  8. Thanks for doing this, I love using clays to clean my hair and now it's good to see that they do. One thing though is I don't use silicone products, heavy waxes or heavy oils like petrolatum, mineral oil not that these are necessarily bad but I don't think the clays could handle cleaning these from my hair.

    1. Oh trust me bentonite can. I had just came off a week of heavy silicone usage while flat ironing my hair. Once done I went straight Iinto slathering on coconut oil as a pre poo(don't know if that was affective with silicone on my hair). then I coated my hair with the clay, left it on for 20 minutes and rinsed it out. BAM! coils popped back into form and my hair/scalp was feeling extra conditioned and cleansed.

  9. i've never used bentonite clay, but i've been impressed with the few times I used rhassoul clay. I still use shampoos though. great experiment!

    1. what about the water only regimen that was recently posted on BGLH? What do you have to say about that?

  10. Thanks for doing this experiment! Now I can feel more confident in using the clay.

  11. Thanks for doing this experiment. I have used both bentonite and rhassoul to cleanse my hair and found them to be similar in terms of cleansing power. I do think that they cleanse a bit better when used with aloe vera juice as opposed to water (maybe you could experiment with this as well. One of the things that I love about using clay to cleanse is less shrinkage!

  12. Thank you for this series. Can you please do this with ACV ? Thanks again

  13. This was an excellent article as usual! I wonder if all of the oil would have been removed if it were left on longer than 2 minutes. I've found my hair to be really clean after using, but I also mix mine with acv and aloe Vera. Then again...I add oil to the mix (mustard/olive) so remnants of oil would probably still show up.

  14. Thank you so much for these articles! I've used both clays, co-washes, and shampoos. It's good to know they are actually getting them clean.

    Would you be willing to do one with diluted shampoo?

  15. The clays seem better than co-washing because it seems that there would not be build up over time (can anyone attest to this?). I also know that in the past after co-washing my scalp would itch. I have heard the clays aren't as likely to irritate the scalp.

  16. Have you compared African Black Soap to shampoo? I would assume that it would have similar results, but I am curious.


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