Monday, April 30, 2012

Why Is This Ingredient In My Conditioner?

©Science-y Hair Blog 2013
I’ve wanted to post this for a while, but it makes me feel a bit subversive because I’m going to tell you that what you think you’re doing with hair conditioner is a wee bit wrong. This is my "ingredient-based" perspective.
Not so many years ago, women washed their hair with bar soap. Many of them knew if they used water from their rain barrels (rainwater) that their hair would shine – because rainwater is soft water so there is less soap scum left on hair. People did not wash their hair often. Nor their bodies. Especially in winter.

Now that so many of us shower daily and have hundreds of soaps and shampoos to choose from, it’s easier to over-cleanse the hair. Enter the “cream rinse.” A cream rinse is the ancestor of modern conditioners. – in the U.S. it was Breck and Wella Balsam that led the pack with fairly simple formulas that helped detangle hair which was dried out from frequent shampooing or damaged by teasing or hairspray and a multitude of other hair “sins.” Wave your hand if you’re old enough to remember Breck and Wella Balsam (go ahead, we can’t see you).

Purple arrow: 18 MEA (larger than life) projecting
from the hair's epicuticle. Green arrow shows the
membrane epicuticle which covers the hair's cuticle
When we put lotion on our skin, we call it “moisturizer.” That’s a misnomer - though a useful one. Nobody is going to say, "hey, I just, coated my hair/skin with emollients and bonded it to conditioners for plasticity and hydrophobicity and lubrication." We use the jargon "moisturize" for that mouthful. In this post, I wrote about the ingredients in skin lotions and what they do for you if you'd like a far more complete list than I'm giving here. What is moisture? Water. Nothing more, nothing less. 

Your hair is designed by nature to grab water and keep as much as it needs or can hang on to. Anything that “grabs water” and holds it is  “hydrophilic” –  water-loving. The protein in your hair, the hydrophilic amino acids in the cuticle layers are designed to be water-loving, hydrophilic. Hair loses water if the air is dryer than the hair and especially if the hair is not coated with the proper hydrophobic (water-repelling) layer. Get it? A water-attracting inner layer covered by a water-repelling outer layer! It's like putting on a raincoat - keeps the rain off, but if you get sweaty inside, you'll stay wet in there. The 18-methyl eicosanoic acid that sits on the epicuticle (that outermost membrane-like layer of lipids and amino acids outside your hair’s cuticle), the cuticles themselves and the oils from your scalp do most of the work in keeping your hair hydrated. 18-methyl eicosanoic acid, or “18 MEA” is amazing stuff. It’s a lipid (fat) so it is hyrdophobic (water-repelling) and resistant to some chemicals and that’s good because when your hair gets saturated with water, it swells and swelling creates stress on the fibers. Healthy hair actually repels water by itself! This lipid layer is the absolute outermost covering between your hair and the environment – also called the “F-layer.” 18-MEA is a fatty acid in a chain-structure, sticking out from your hairs. It is covalently bound and cross-linked like “chain mail” armor, and is bonded to the proteins in the epicuticle (not just floating on top). This layer can be removed with peroxide or alkaline substances such as hair relaxers, chlorine (swimming pools, heavily chlorinated tap water). This is a very strong protection for your hair, indeed. Cosmetics suppliers are in the process of manufacturing synthetic 18-MEA, but keeping your own is better.
©Science-y Hair Blog 2013
If you strip off the outer layers of oils, your hair will tangle more easily, look dull and be more easily dehydrated. In addition, hair is subject to weathering, and damage from everyday activities. Cuticles can crack or break, leaving open spaces with little protection. So if we want our hair to look good and feel good, we try to support or mimic the natural protection of hair itself by providing humectants such as amino acids and emollients (occlusives) to prevent dehydration. These mimic the actions of the "ingredients" on the outer regions of our own hair, but do not replace hair's own natural components.©Science-y Hair Blog 2013

Sorry that was so chopped-up, but it establishes the background for the fun part. Ingredients are meant to be listed in order of greatest to least concentration. The first few ingredients are the most active. The rest are either “window dressing” or preservatives, colorings, fragrances and pH adjustors. Once you get past “fragrance” and preservatives, the ingredients included are at a very low concentration. I rarely put more than 6 or 7 ingredients in conditioners that I make.©Science-y Hair Blog 2013

This is the ingredient list from Suave Naturals Tropical Coconut conditioner – what is in it and what those ingredients “do:”
Water - Solvent. Without water, your conditioner would be a solid lump.
Cetearyl Alcohol – Fatty alcohol, but not like the alcohol you drink.  The raw material is a creamy, waxy solid which leaves a silky, powder-like feel on your skin of you rub it between your fingers. This ingredient gives hair a soft feel, may coat the hair shaft slightly but is unlikely to penetrate deeply. Thickens the conditioner, may be occlusive (emollient)
Cetrimonium Chloride – A “cationic conditioner”(quaternary cationic surfactant) which has a positive charge to bond to the more negatively-charged hair, especially where hair is damaged. This ingredient leaves behind a very thin layer of molecules to help hair resist friction that would make combing difficult and helps it resist tangles. Good detangler.
Potassium Chloride – a salt, used to thicken the formula
Distearyldimonium Chloride – Another cationic conditioner, not necessarily as good a detangler as the first
Disodium EDTA – anti-odixant, helps in preservation and stabilization of the formula, at high enough concentrations can help remove minerals from hard water build-up.
Glycerin - Humectant
2 Bromo 2 Nitropropane 3 - Preservative
Methylchloroisothiazolinone - Preservative
Methylisothiazolinone -  Preservative
Propylene Glycol – Humectant and solvent
Silk Amino Acid - Humectant
Honey/Mel – I assume this is a stabilized form of honey. Humectant
Nettle (Urtica Dioica) Extract, Rosmarinus Officinalis (Rosemary) Extract – Herbal extracts which have been stabilized and preserved. Very low concentration.
Cocos Nucifera (Coconut) Extract – Uncertain, this may be coconut oil.

So you use this conditioner and you have the cationic conditioners and fatty alcohol acting as emollients/occlusives to help prevent dehydration. They also give that slippery feel that conditioners usually have and make your hair feel soft and pliable (plastic). Here is a post about plasticity.
The humectants and amino acids may help your hair hold on to moisture in the presence of the emollients. I loved this conditioner, but the 2 Bromo 2 Nitropropane is a formaldehyde-releasing preservative, and a not-uncommon irritant or allergen.

©Science-y Hair Blog 2013
What you’ve done is to try to mimic what your hair already has (or had when you were a kid) with a conditioner.

Let’s consider another formula – Yes To Carrots Pampering Conditioner:
Water - Solvent. Without water, your conditioner would be a solid lump.
Cetearyl Alcohol – Combination of 2 fatty alcohols, but not like the alcohol you drink. This ingredient gives hair a soft feel, may coat the hair shaft slightly but is unlikely to penetrate deeply. Thickens the conditioner, may be occlusive (emollient)
Behenalkonium Chloride - A “cationic conditioner” (quaternary cationic surfactant) which has a positive charge to bond to the more negatively-charged hair, especially where hair is damaged. This ingredient leaves behind a very thin layer of molecules to help hair resist friction that would make combing difficult and helps it resist tangles. Good detangler, adds some “bounce” to hair, helps emulsify the formula (so it doesn’t separate).
Cetyl Esters – Emulsifier which adds a silky, elegant feel and prevents separation of formula.
Daucus Carota Sativa (Carrot) Juice – For color? 
Daucus Carota Sativa (Carrot) Seed Oil – Oil with some good qualities for skin and hair
Dead Sea Water (Maris Aqua) – Probably “Dead sea salt” to thicken the formula.
Maris Limus Silt Extract (Dead Sea Silt) – Silt is a soil particle which is fine and powdery. If they are adding real silt, it may be to give the formula a nice texture and feel because some clays and silts are used to thicken cosmetics with or without making them look opaque or become too thick or "gelled."
Chamomilla Recutita (Matricaria) Flower Oil – Chamomile oil (a daisy-like flower) – we’re now in the land of “low concentration” - which is usually where you want oils in a conditioner. Cross-allergen with ragweed.
Olea Europaea (Olive) Fruit Oil – olive oil, great for hair, emollient/occlusive.
Prunus Amygdalus Dulcis Oil (Sweet Almond) – almond oil, another great oil for hair emollient/occlusive.
Calendula (Calendula Officinalis) Flower Seed Oil – Calendula (a daisy-like flower) oil, also potential cross-allergen.
Cucurbita Pepo Fruit Extract (Pumpkin) – In the land of “things added because they sound good” for the next 2 after this one.
Ipomoea Batatas Extract (Sweet Potato)
Cucumis Melo Fruit Extract (Melon)
Simmondsia Chinensis (Jojoba) Seed Oil – a good oil for hair, but there is very little here, emollient/occlusive.
Triticum Vulgare (Wheat Germ) Oil – a good oil for hair, but there is very little here, emollient/occlusive.
Citrus Aurantium Dulcis (Orange) Fruit Extract– For scent, possibly
Honey Extract - Humectant
Punica Granatum Extract (Pomegranate) – Perhaps because it sounds good
Guar Hydroxypropyltrimonium Chloride – A Cationic-modified plant gum for mild detangling and de-frizzing
Sodium Hydroxide – raises pH
Sodium Benzoate - Preservative
Potassium Sorbate - Preservative

See how most of these ingredients are possibly redundant? The ones that matter most are the cationic conditioner, the emulsifier, and the oils. The Guar and Honey extract are a good addition.
©Science-y Hair Blog 2013
So what's your point?
So do these conditioners moisturize? No. Water moisturizes. The natural makeup of your hair self-moisturizes and self-protects if you treat it gently. Conditioner is a tool to help prevent dehydration and reduce friction and breakage. Like a lip balm. Or shoe polish. Or furniture oils and polishes. It's the gentle care you give your hair and the thoughtful choices you make in the products you use that put your hair in a well-moisturized state. The products and ingredients themselves are just tools; means to an end. A hammer does not put a nail in a board. A person uses a hammer to put a nail in a board using their strength and skills - you see? 

How does conditioner prevent frizz?  If your hair is dry and therefore looks rough, dull and frizzy, the added plasticity or flexibility from conditioner, the weight from conditioner, will help your hairs align with each other. The hair will retain the moisture necessary to be flexible and express its wave pattern. Because the conditioner occludes moisture, hair is less likely to frizz in high humidity (swell with water and lose definition) or in low humidity (losing moisture and definition).
If your hair is very frizzy, the weight of a lot of conditioner weighs down those hairs that always escape to give you that fuzzy look. But if your hair is fine and thin, a lot of conditioner will literally be a heavier load than your hair can carry and still wave or curl.©Science-y Hair Blog 2013

Am I splitting hairs? Maybe. I'm kind of nit-picky about "how things work" and because once I began making my own conditioner, I discovered just what these ingredients do and no not (do). Hair conditioners do not make hair healthy by themselves. It is our responsibility to protect our hair from damaging forces if we want lustrous hair. Conditioner is an aid, not a cure.

Take-Home Message:
Humectants attract moisture to hair: Aloe vera, amino acids, (and proteins) glycerin, honey are examples. These need the protection of emollients to prevent dehydration.
Emollients seal moisture in the hair and out when necessary: oils, “butters” like shea or cocoa, cetyl alcohol are examples.
Cationic conditionershelp detangle and reduce friction.
Here is a longer list of these ingredients (at the bottom of the page).

Source: Chemical and Physical Behavior of Human Hair 
Robbins, 1994. 3rd Ed. Springer-Verlag, New York

Rodney D Sinclair Journal of Investigative Dermatology Symposium Proceedings (2007) 12, 2–5. doi:10.1038/sj.jidsymp.5650046 Healthy Hair: What Is it?
Department of Dermatology St Vincent's Hospital, The University of Melbourne, Victoria, Australia


  1. Great post. I was thinking this when I bought a 5litre keg of 'basic conditioner', I deemed it better than most popular conditioners on the market today. It had the main ingredients in the top 5, after that it was just preservatives and no "window dressing" as you call it.
    It tickles me at times, when reading ingredient lists and wondering what agents like 'pomegranate' and 'melon' are really supposed to do.

  2. It tickles me too. I'd rather eat the pomegranate and melon than put it in my hair. It will do more good via that route!

  3. YTC was my fave conditioner with this fomula. Unfortunately, they've changed the formula now by reducing emollients and adding glycerin, so porous curlies may have odd responses at high or low dews / humidity with the new formula.

    But I have a few questions about the ingredients of the old formula you posted:
    * Which ingredients made YTC extremely thick and creamy for a conditoner? :) Because most conditioners on ground feel more watery, even though some oils are added.
    * By which ingredients does my hair get a lot of hold on wash day as if I have a gel cast? Is it because of the cetyl esters?
    * After applying or touching the conditioner I get a kind of non-smooth feeling on my fingers when I rub them together. I also have that feeling with other conditioners. Which ingredient causes that non-smooth feeling at rubbing?

    1. Sera,

      The ingredient(s) that makes this formula so thick are the combination of Cetearyl alcohol (thickness, creamy texture - slightly more thick than Cetyl alcohol), Behenalkonium choride and Cetyl esters.

      Cetearyl alcohol can thicken, but it needs the cationic Behenalkonium choride and Guar hydroxypropyltrimonium chloride to keep the product in suspension (so it doesn't separate). Cetyl esters are a waxy thickener that makes a formula extra thick and creamy and nice-feeling.

      These are the ingredients for the YTC Pampering Conditioner and a look at their website doesn't show a change in ingredients. Maybe I'm missing something.

      My guess is that it is the combination of ingredients listed above that leaves a slight cast in your hair *and* gives you a not-smooth feeling between your fingers. Ingredients work synergistically. Individually, they behave one way and together, they behave another way. The most likely individual ingredients to give you the "gel cast feeling" are the Cetearyl alcohol and Cetyl esters.

    2. Hi Wendy,

      Thank you for your explanation about the effects of the ingredients.

      My guess is that only in Europe the formulation has been changed, as I took a look at the UK website of YTC and found a picture of the new bottle:

  4. Hi! First of all, thank you for providing such great scientific explanations of hair care and how it works, it's so hard to find solid info about this kind of thing.

    On your "Product List By Category" page you have a section for conditioners that may add volume. What is it about the formulation that causes this effect?

    1. It is the inclusion of (for most of the products) Stearamidopropyl dimethylamine. That cationic conditioner (surfactant, actually) is reasonably helpful for wet-hair detangling, but tends to increase friction a little bit once hair is dry. Friction prevents hairs from settling in too snugly nest to each other and going limp.

  5. Hello! Thank you for this post as it has come the closest to answering a question I have. Hoping you can expand for me :) I have naturally curly/kinky hair and the advice I constantly see is to keep hair hydrated, hair loves water, hair isn't healthy unless it's hydrated, dry hair isn't good, etc. My scientific side seems to see the opposite advice - healthy virgin hair repels water, hair is weakest when wet, the more damaged and older hair is the more water it absorbs, etc. This has left me quite confused. If our hair (in it's healthiest state) is hydrophobic why do some people go out of their way to make their hair absorb as much water as it can and then work to make it retain said water? Isn't that damaging? Doesn't it go against healthy hair's nature? I hope this makes sense!

    1. Hi theDine inDiva,
      That always does seem contradictory, doesn't it? Chemically un-treated, healthy hair is water-repellant - hydrophobic. At least on the outside. Hair doesn't want to get "waterlogged" the instant it goes in the water. The inside of hair is hydrophilic! On the inside, out hair needs to retain water so it can be flexible. Virgin hair will soak up water, it just needs a few minutes of thorough saturation to do it. Damaged hair tends to soak up water more quickly - so given, say, 3 minutes of time in water, damaged or porous hair will soak up more water than low-porosity hair.

      All hair can get dehydrated, even the healthiest of hair will dehydrate in dry air, wind, or hot sunlight. When it does, it gets less flexible and loses definition. Hair needs good hydration to stay flexible and elastic. And in products, it needs some good humectants to help prevent dehydration.

      Hair is weaker when wet. Healthy hair becomes more elastic when wet, so it's easy to over-stretch it without careful handling. Damaged hair tends to become more fragile when wet and is over-stretched much, much more easily than un-damaged or low-porosity hair.

      I keep things clear (to me) by thinking in terms of hydration, flexibility and lubrication. Hydration is making sure hair gets that heavy, saturated feel in the shower, and then choosing conditioners, leave-in and styling products that contain humectants to help hair hang on to water no matter what the weather or indoor environment. Flexibility comes from hydration and also from lubrication like oils and conditioners. Just like we would put an oil or a cream on our skin to keep it flexible and soft, we put oil or creamy products in hair to keep it soft and pliable. Water alone or humectants alone aren't enough. Lubrication means hairs can slide past each other and tends to give a smoother look and feel with less friction.

      People who are working hard to maintain as much hydration as possible are emphasizing flexibility. Even in virgin hair, some hair needs more products and more effort to stay hydrated and flexible. That might be due to hair-width or how flexible hair feels naturally, or due to hard water making hair feel dry or stiff, a dry climate or indoor heat or air conditioning, or just personal preference.

      It's not necessarily damaging to try to get hair to retain as much moisture as possible with humectants and oils. The air is always going to pull water out of your hair unless the humidity is tropically high. And even then, hair isn't waterlogged like it is when it's actually in water.
      Best wishes, W

  6. How do you make your conditioner? Is it with the components above or just mixing all natural stuff?

    1. Hello Virginia,
      I recommend you check out the blog "Point of Interest!" where you can find great tutorials and recipes for making your own conditioner. This link may not be active - copy and paste:

    2. Just found your amazing blog! Very knowledgeable and informative! I am very interested in following you. I was trying to open this link But I couldn't. It looks like I have to be invited to read this blog. How can I request an invitation? Thank you so much!

    3. You'll have to communicate with the person who writes that blog, which is now on a subscription service.

  7. Hi,can you advise if Cetyl Esters is water soluble & cowashable without shampoo please?
    Great Blog!

    1. Cetyl esters are not soluble in water, they are oil-based. They are like many of the ingredients in hair conditioners that make them creamy or conditioning - non water-soluble. Cetyl alcohol, Behentrimonium chloride, Cetearyl alcohol, Stearylkonium chloride - all are non water-soluble.

      Cetyl esters should be removed all or in part by shampoo. Ingredients like this tend to "wear off" too. Conditioner-washing has limited ability to remove oil-based ingredients.

  8. I refresh my hair daily with water and a touch of conditioner from a spray bottle. I normally diffuse for a minute or so to get some volume after I lightly spray my hair. Am I defeating the purpose of hydrating my hair when I add heat from the hair dryer? Thanks Wendy.

    1. You are probably not dehydrating your hair unless you used the dryer on "high" and "hot." You're adding water enough to re-set the roots, and then evaporating it quickly - and that process can be dehydrating. But you're not *thoroughly* saturating your hair with water so it becomes all wet and heavy and soft, so it's not really going from soaking wet to dry (which is when hair-dryer drying-damage can occur). So my guess is that you're probably not getting a "net" effect of more dehydration from that styling step. You're probably coming out about even.