Cocamidopropyl Betaine

cocamidopropyl betaine

Cocamidopropyl betaine is a bit of a mouthful, but that doesn’t stop it from being one of the most widely used ingredients in shampoos and foam baths.  Wikipedia is a good source of information on cosmetic ingredients as a rule, but the entry on CAPB is a bit opaque and was clearly written by someone who knew their chemistry but probably hadn’t had much to do with this widely used material.  In particular, he missed the main thing that motivates people to us it, which is bubbles.

People love bubbles.  I love bubbles.  It is perfectly possible to come up with a liquid that washes your hair perfectly adequately and which doesn’t create bubbles.  But where would the fun be in that.  And nobody would buy it.  CAPB doesn’t create the bubbles but it stabilises them.  If it did nothing else, that would be enough to earn its ticket.  But it has another trick up its sleeve.

CAPB is relatively mild,  but anything with a cleansing action can damage the skin.  Nobody has yet worked out a way of removing dirt and grime without also removing some of the skins protective oils at the same time.  But by blending a couple of different ingredients you can come up with some formulations that are pretty close to that ideal.  Interestingly, how irritating the individual components is doesn’t really give you much idea of how a blend will behave. The most commonly used blend is CAPB, sodium laureth sulphate and cocamide DEA.  You see this time and time again because it works so well.  It is also a pretty non-irritating blend.

When I first started working in cosmetic formulation in the early eighties it used to be normal to have different products for salon use.  So a salon shampoo would have much higher levels of detergent than a simple consumer one.  The idea was that a shampoo at a hairdressers needed to be a rather more special event than just washing your hair.  This all made sense but it did mean that the people working in the salons tended to get exposed to rather a lot of detergent.  The occupational health practitioners picked up on this and tended to pick on CAPB as the main culprit – logically  enough as it tended to be in nearly all the formulations.   Since then the tendency has been for detergent levels in consumer shampoos to increase towards the levels that used to be regarded as appropriate to salon use.  This has partly been marketing driven – marketers like putting the word ‘salon’ on their bottles.  It is also bubbleophilia in action again.  Given the choice buyers go for bubbles.

But on the whole irritancy is not a problem for most people most of the time.  We have all worked out our own routines which have become habits.  It is worth bearing in mind that if for any reason you do decide to increase the amount of shampoo you use that there may be a level that starts to affect your skin.  It will also degrease your hair shaft making it more brittle and possibly damage the surface of the hair making it less glossy and harder to manage.  The nature of the chemistry is such that it is the blend that is having these effects not the particular ingredients, so there isn’t much to be learnt by studying the ingredient list.  And if you do have a bad experience with a particular product lowering your use level might be just as effective as changing brands.

On the whole CAPB is a fun ingredient.  It helps to make our hair washing and bathing experiences that much more enjoyable.  And when we have finished with it is highly biodegradable so you don’t even need to feel guilty about it.  Harmless fun for everyone.

8 thoughts on “Cocamidopropyl Betaine

  1. Pedro

    Some Brazilian brands use Cupuassu Amidopropyl Betaine instead of Coco Amidopropyl Betaine. It’s almost the same thing, but Cupuassu is a native Brazilian plant, so, I think it’s better for the enviroment.

  2. Rebecca

    Hi Colin,

    Can you tell me of an effective bubble solution for a bubble machine/wand? I need to be able to source ingredients in the uk.
    Thanks in advance,
    Rebecca

  3. Robert Goodman

    Actually cocamidopropyl betaine, like most other alkamidopropyl betaine surfactants, does produce foam on its own, in addition to being a foam stabilizer for other surfactants.

    Another property alkamidopropyl betaines have is that they and at least some anionic surfactants reduce each other’s irritancy. So if you blend CAPB with SLES, the mixture has a lower irritancy than SLES or CAPB alone.

  4. Colin Post author

    Thanks for the enlightenment Robert, though I don’t think I actually said that cocamidopropyl betaine doesn’t foam on its own. The point about the synergy of CAPB and SLES reducing irritancy is a good one, and I think that is one of the reasons that a lot of natural shampoos are actually more irritant than conventional ones even though on paper they are using less irritating ingredients.

  5. Anne

    Hi Colin,
    I have stumbled onto your website and am hoping you could advice me on a shampoo and conditioner without Cocamide DEA and Mixed dialkyl thiourea as I have very bad reaction to these which put me in hospital and I and now on a immunosuppressive called
    Azathioprine.
    Hope you can help?
    Thanks Anne.

  6. Colin Post author

    Hello Anne,

    I am afraid all I can advise is to look on the ingredient lists. Cocamide DEA is a common shampoo ingredient, so I am afraid you’ll probably have to look quite a while to find one without it. I’d steer clear of Cocamide MEA as well. Conditioners very rarely contain it, so that is some good news. I have never personally come across a cosmetic containing any dialkyl thiourea, but it is regulated for use in nail and hair products so I guess somebody somewhere might be using it. The regulations require a warning on the pack that says “Contains DIMETHYLOL ETHYLENE THIOUREA”, so it will at least be easy to spot. (Dialkyl thiourea is the chemical name for the class of products, DIMETHYLOL ETHYLENE THIOUREA is the official EU name for the only member of that class used in cosmetics.)

  7. Tina

    Hi Colin,
    I am allergic to both CAPB and methylisothiazolinone so I have been struggling to find a shampoo with chemicals I can use (since natural shampoos leave my hair feeling greasy). I found a shampoo that does not have these chemicals, but does have cocamide MEA. Is this ingredient too similar to CAPB? I found out the hard way that coco betaine is the same as CAPB so I’m hesitant to try another ingredient that sounds similar. Any advice you could offer would be appreciated.

  8. Colin Post author

    Hello Tina, I am afraid there is no way to answer that question. The way allergies work is that a particular part of a given molecule is what triggers it off. A molecule that shares the same bit might well illicit the same reaction. Cocamide MEA is not particularly similar to to CAPB in structure so there is a good chance it won’t give you a problem, but the only way to be sure is to try it.

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