Wednesday, 3 October 2012

Deep Conditioning : What Ingredients in Hair Conditioner Penetrate Hair?

Continuing on with the deep conditioning update, here is the comprehensive list of every conditioning ingredient that I could find that penetrates hair.

I have grouped the hair into two groups. Natural hair with no processing and hair that is processed or damaged.

Often penetration tests are done at  35°C which corresponds to surface body temperature or what you would get if you applied a conditioner and covered your head with a shower cap.   

The Short Story 

Natural Hair - No Processing
-water
-hydrolysed wheat protein
-coconut oil
-cetrimonium bromide
-caffeine
-panthenol

Bleached Hair, Relaxed Hair or Damaged Hair (i.e cuticle damage)
- everything in the unprocessed natural hair list above
-some amino acids enhanced by being in a creamy conditioner (arginine, glycine, glutamic acid, phenylalanine, histidine)
-artificial peptides (similar to hydrolysed protein)
-some silicones or amodimethicones (Trimethylsilylamodimethicone)
-hydrolysed palm oil
-18MEA

The Long Story 

If you would like extra details on times, temperatures and penetration depths, here are the details you are looking for:

Natural Hair - No Processing

1. Hydrolysed Wheat Protein (J Cosmet Sci pp 193-203, 2000)

Time required for penetration: 30 minutes at  35°C for initial detection, 16 hours (overnight simulation) for maximum detection
Penetration depth: in between cuticle layers and also in the cortex for natural hair, mainly in the cortex for bleached and relaxed hair

Process Details
-Tests carried out on natural hair, bleached and relaxed hair.
-Hydrolysed wheat protein was dissolved in water prior to application.
-Penetration seen in all hair.

2. Coconut oil (J Cosmet Sci pp 169-184, 2001)

Time required for penetration: Overnight
Penetration depth: in between cuticle layers and also in the cortex

Process Details
-Tests carried out on natural hair
-Coconut oil penetrates on dry hair

3. Cetrimonium bromide (CTAB or CETAB)  (J Cosmet Sci pp 169-184, 2001)

Time required for penetration: 6 hours at  37°C
Penetration depth: in between cuticle layers and also in the cortex

Process Details
-Tests carried out on natural hair
-Cetrimonium bromide was dissolved in water prior to application on hair

4. Caffeine and Panthenol (British Journal of Dermatology, pp24-30, 2011)

Details not clear. Treatment is described as a leave in treatment.


Bleached Hair, Relaxed Hair or Damaged Hair (i.e cuticle damage)

1. Some Amino Acids ( J Cosmet Sci pp 347-357, 2007)
Time required for penetration - 3-10 minutes at 35°C
Likely penetration depth - cortex

Process Details
-Tests were only done on bleached hair but not untreated natural hair.
-Mixing the amino acid in conditioner enhanced or caused uptake.
-Arginine is taken up by bleached hair in conditioner and in water (pH 6).
-Glycine and Glutamic Acid are taken up by bleached hair provided the amino acid is in conditioner and not dissolved in water (pH 6).
-Phenylalanine and Histidine are taken up by bleached hair when the amino acids are dissolved in water.

2. Some silicones - Amodimethicone or Aminosilicones ( J Cosmet Sci pp 231-245, 1995)

Time required for penetration - 20 minutes
Penetration depth - In between the cuticle layers and also in the cortex

Process Details
-Tests carried out on bleached hair.
-Trimethylsilylamodimethicone is taken up by bleached hair when the silicone is added to a conditioner.

3. Artificial Peptides (similar to hydrolysed protein) - (J Cosmet Sci pp 339-346, 2007)

Time required for penetration - 5 hours at 37°C
Likely penetration depth - cuticle layers

Process Details
-Tests carried out on unprocessed natural hair and bleached hair.
-No penetration seen on natural hair but bleached hair does show cuticle layer penetration.

4. Hydrolyzed Palm Oil - (International Journal of Polymer Anal. Charact pp 21-28, 2012)

Time required for penetration - 30 min at 40°C
Penetration depth - cuticle layers and outer cortex

Process Details
-Tests carried out on bleached hair.
-Penetration seen in the outer layers of hair.


5. 18MEA -a fatty acid/lipid or oil found in hair  - (Surf. Interface Anal pp 298-301, 2011)

Time required for penetration - 1min 30s
Penetration depth - cuticle layers

Process Details
-Tests carried out on bleached hair.
-Penetration seen in the cuticle

28 comments:

  1. I'd be interested to hear if you know of any studies including hempseed oil for hair care.

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  2. Great research. I guess we can conclude from this data that deep conditioning overnight is the best method for moisturizers to penetrate the hair.

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    Replies
    1. No I don't agree with that. The reason why certain things like coconut oil require overnight time points is related to size. Most of the smaller ingredients like proteins, amino acids or very small lipids like MEA only require a few minutes.

      Many of the overnight time points are used to illustrate what would happen in a leave-in product, rather than intended for a normal conditioning process.

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    2. Hi there, now I am a bit confused. From the article, I would have come to the same conclusion as CurLeeGirl that, for ingredients such as coconut oil and hydrolyzed wheat, overnight would be the best option for maximum penetration. As you mentioned in your reply to Laura, overnight to scientists usually means 8+ hours.

      So, if overnight conditioning is not the best option, what would you recommend is the best way to use a deep conditioner if we want the benefits of coconut oil, etc.? I know that you mentioned leave-ins, but what about deep conditioners?

      Thanks!

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    3. I have only listed the methods, there is further research to come in terms of the implication for hair when you soak it in water for a long time. There is a big difference between soaking hair in plain oil which is water free as opposed to soaking hair in a water rich conditioner. So it is not as straightforward as saying overnight makes the greatest impact therefore is the best..........more detail and explanation to come next week!

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  3. Interesting stuff. Thanks JC.
    Does "overnight" for the coconut oil to penetrate mean allowing it to be on the hair 8 or 16 hours?

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    Replies
    1. The scientific journal did not quote an hourly time point. I would say that as a scientist overnight usually means anywhere from 8 hours or more.

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    2. First of all, I should state that I am very impressed with the staggering amount of useful information on this website. I have just stumbled across here recently and have been reading many of your posts but I have not yet been able to confirm one concept. What would be the difference between applying coconut oil for 8 hours during the day versus applying it overnight while having slept for 8 hours? My apologies for the bump to this thread about a year later but I have never found a conclusive answer to this question and I was hoping you would be able to clarify this for me. Thanks again for sharing all this knowledge with us.

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  4. Regarding Hydrolyzed Wheat Protein - You state that in the test the substance was dissolved in water. Is that the same thing as having hydrolyzed protein in a conditioner or a leave in spray? How is maximum penetration measured? Is there a recommended amount for hair?

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    Replies
    1. No, dissolved in water means literally that - some hydrolyzed protein in water (commercially this would be like aphogee two step, komaza protein hair strengthener.....these are normally none creamy, mainly hydrolysed protein in water, scent of the product is usually not the best). If you were to add a few drops of Aphogee or Komaza to your rinse out conditioner or a creamy leave in then you are simulating the hydrolysed protein dissolved in conditioner.

      To be fair the technique used to see penetration is strictly speaking not a quantitative method. What happens is after 30 minutes, there is clear detection of the protein. If you leave it on for longer, you can visually see more protein.

      In the first case (30 minutes) this is the benefit of using hydrolysed protein in a regular conditioner/deep conditioner. In the second case, it is perhaps illustrative of what would happen if there was protein in your leave-in treatment

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  5. Fascinating! Regarding the silicones, what would be the benefit of having silicones penetrate to the cortex? I understand their functioning for smoothing and sealing, but not for actual conditioning (ie improvement) of the hair.

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  6. FYI - To the person/ persons concerned - I am officially deleting any comment mentioning a new natural company which makes products with argan oil as the high level of commenting recommending this product with blogger id's which are blocked or empty makes me know that this is spam. Do your business cleanly, you do not need to spam.

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  7. Jc your blogformation has helped me so much! I started a year ago really taking care of my hair and needed all the help both scientically and spiritually. Thank you again for elevating my understanding through your thorough research. Have a blessed weekend! :o)

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  8. JC,

    So I just knew I'd see Extra Virgin Olive Oil on this list. Can you explain why coconut and not olive?

    As a hair care sepecialist staying current on ingredients that give the maximum benefit is very important to me. :-)

    -Ms. Amena
    fb/instagram:: Torrid Tresses by Ms. Amena

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    Replies
    1. It is not to say olive oil doesn't, it has just not been tested. One science article suggested that olive oil may penetrate hair but this list in this article is exclusively for tested and proven substances only.

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  9. JC,

    I understand. Thank you very much. Appreciate all that you do!

    -Ms. Amena
    fb/instagram: Torrid Tresses by MsAmena

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  10. I recently bleached/dyed my all natural 3c hair. I have been very anxious about the damage (although I love the results of the coloring). There was tangible change to the texture, strength and long-term look post styling. I began to research treatments need to prevent breakage and help with the changes to the hair. Protein conditioning is what I found to be needed. I then wanted to know what/which would be best and no one- no where would ever state. Your article helped me to breakdown what I should be looking for. I quickly found that the $60 that I was contemplating spending was at all no better than the $5 treatments. So, I sincerely thank you.

    Elle Ollie, Washington, D.C.

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    Replies
    1. You are so welcome, glad I could help :)

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  11. In the Process Details when it shows that certain details were found or will most likely enter the cortex are is this result permanent? Will the protein remain in the cortex once it enters? Also, which D.C. category for Damaged/Colored hair does Aphogee 2 step treatment fall under?

    ReplyDelete
    Replies
    1. To answer your questions

      1. The binding of the conditioning substances (all listed above) is temporary. Oil that penetrates can also exit. Hydrolysed protein that penetrates can also exit. How long it has an effect depends on how you handle your hair (amount of wetting /combing etc). Most treatments will fade after 1-3 washes.

      2. Aphogee contains hydrolysed keratin so it is in the hydrolysed protein category

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  12. Hi JC,

    I am so grateful for your blog and your willingness to investigate responses to our questions. I mix my hair products in my kitchen, and there is a whole list of oils I am curious about. As a lay person with as much as an AP chemistry background (from over 10 yrs ago...) how could I go about testing the efficacy of different oils for deep conditioning? What are some indicators I could use to compare results? Am I asking too much? I appreciate any suggestions you may offer. Thanks!

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    1. On a non-laboratory scale, it is difficult to do. At the very least,you need some specialist equipment for example a balance with a high level of accuracy (0.01 g error or more). I actually have one at home so I might try out an experiment.

      The best tool which has been used for the studies above is called a TOFSIMS. It can detect and map oil penetration into hair. This tool however is highly specialist and expensive to operate, so only a few research laboratories in the world have one.

      I think on a non-laboratory scale the only indicator of efficacy is consumer testing i.e do you think that the oil works well on your hair, is your hair softer, easier to detangle, retaining moisture?

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    2. I think consumer testing is the best that I can do, so I will continue with that. Thank you so much for answering my question, especially so quickly. Looking forward to reading more of your findings!

      Delete
  13. Hi I love your site thank you!
    Just wondering your thoughts on adding gleatin to final shampoo and leaving it on hair for 5 mins or so before rinsing and a treatment in an attempt to add hydrolized protein?
    Also how about a mister bottle of beer to add wheat protein?
    I have bleach blonde long hair which is fragile. I like to add coconut oil at night to mid lengths and ends then shampoo in the morning.

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    Replies
    1. Gelatin is probably fine since it is hydrolysed protein. Beer is less straight forward but many people do use beer to condition hair

      Delete
  14. Hi Jc,
    Your site has been a blessing for me. Thank you for all the great research! You're one of the very few people I trust when it comes to natural hair care info!
    Last weekend (10/20/2012, Saturday) I decided to make a semi-homemade leave-in conditioner using some of the deep penetrating ingredients you mentioned in this article. I call this the coffee spritz: In a 4oz spritz bottle I added:
    filled 1/2 of bottle (2oz) with Giovanni Direct Leave-In (panthenol), 2 teaspoons of coconut oil,
    1/2 teaspoon of Aphogee keratin 2 minute reconstructor (hydrolyzsed protein), filled the rest of the bottle with Starbuck's dark roast coffee (caffeine). I slathered this onto my hair after washing and deep conditioning my hair in braids (my own natural hair braided) and I did not rinse this out or take out the braids. What can I say? I'm not much of a coffee drinker and the coffee smell was annoying but I did notice the next day (Sunday)that my braided hair held more moisture and I didn't need to remoisturize. I spritzed more of this solution onto my still braided hair before going to bed that night (coffee smell not as strong) and when I woke up again the next morning (Monday) my hair still held this incredible moisture. I decided not to spritz my hair yesterday (Tuesday) morning or night and today (Wednesday) my hair feels a bit dry, actually hard in some places. I unbraided some of my braids, some were dry and believe it or not some of the braids were creamy soft with moisture. So I think I may tinker a bit with this "coffee spritz", tone down the coffee smell and use it again. Do you think the extra moisture I felt was the result of combining many ingredients that are known to penetrate the hair or is this just my imagination?

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    Replies
    1. lol I cannot say. If you like it, keep doing it :)

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  15. Wow!! As a scientist and owner to a beautiful head of natural hair, I have to say, I LOVE your site. Thank you so much for your efforts- they're so appreciated.

    ReplyDelete

Your comments and questions are very welcome. Please do not include any links and stick to the topic. If you have a burning question unrelated to the article, please email it to me. All comments are moderated so there may be a slight delay before your comment appears on the blog. Thanks for taking the time to comment!