Thursday, March 20, 2014

Oil Pre-Shampoo or Pre-Wash (And how to make it work for YOUR hair)

Science-y Hair Blog © 2011 by  Wendy M.S. is licensed under CC BY-NC-ND 4.0 

The previous blog post included information about how oil pre-shampoo treatments work.

If your hair is at all porous - even just a tiny, little bit, if it ever gets tangly or poofy or frizzy and seems like it needs weight, if washing it makes it seem to float in the air or if the ends of your hair seem to get wispy and disappear, oil pre-wash treatments can help. Oil pre-wash treatments add flexibility, softness and "weight" to hair. And when you think of "well moisturized" hair, you are referring to a number of qualities, two of which are flexibility and softness.

Here's the deal:
You know how washing your hands regularly can make them dry or chapped - even if you don't use soap? Washing your hair ultimately dehydrates it too unless your hair is tremendously low porosity. By that I mean the cuticles are un-damaged and in such pristine condition that they don't let water in at all. Porosity is a surface thing. Oils have other great effects like making hair soft and flexible - those are partly related to porosity. Even low porosity hair can get dried out with too much washing or dry air or a lot of sunshine.

Any oil will keep the water out of your hair for a little while and that is great. Many oils can surround any chipped and broken places in your hairs cuticle covering, giving you better protection.

Hair-penetrating oils are ideal for some people's hair because they "waterproof" the inner part of your hair that swells. If we can keep water from getting into our hair and swelling it up, it won't end up waterlogged and the cuticles will chip off less and we'll keep our lovely proteins and everything that keeps out hair strong from escaping down the drain.

My top picks for oil pre-washes and pre-wash blends: 
Penetrating oils for managing porosity and softness: Coconut oil, fractionated coconut oil, sunflower oil, babassu oil, olive oil, avocado oil, palm kernel oil, a blend of these oils and any others you like. Castor oil is good for some people's hair.

Lubricating oils for slip and flexibility: Broccoli seed oil, jojoba oil, sunflower oil, sesame oil.

Oils go on dry hair! For an oil pre-wash treatment, apply oil directly to your dry hair. That gives you more control over distribution than wet hair and the oils can penetrate without water getting "in the way." It's okay if you have some conditioner or styling product in your hair.

Not every oil and every application volume is right for everybody!
Coconut oil is great for hair that usually feels dry or rarely feels soft. Coconut or palm kernel oil - the serious hair-penetrating oils are ideal for hair that is not easily weighed down. Babassu oil is a good penetrating oil for hair that is  easily weighed down. Think of hair-penetrating oils as "active ingredients." Some hair needs full-strength hair-penetrating oil.

Butters are good in moderation for hair that needs a thick, creamy, heavy pre-wash treatment. Butters can build up on hair - feeling waxy or making the hair get dry almost immediately after getting out of the shower or a draggy feel in dry hair. Trial and error!

If your hair is easily weighed down, hair-penetrating oils need to be blended into other oils so they don't overwhelm your hair. Lesser-strength, but still active! If that still doesn't work for you, then light oils such as grapeseed may work.

Your hair's response will tell you which oils are too heavy, too "light" or just right. Don't worry about what works for somebody else or what you've been told or even what you expect to work. Try different things. Use what works for you.

A conditioner containing oils can work too.

How Much Oil?
Some people can use lots of oil - so much their hair looks a little greasy. This is likely to be porous hair that feels dry and acts brittle, soaks up lots of conditioner without getting greasy or limp.

Others need to use enough oil to make the hair shine, maybe look and feel a little more heavy than usual and needing to be washed. This might be you if your hair is normal porosity and porous on the ends - but not necessarily every time you use an oil pre-wash.

If it always feels like oils sit on top of your hair, you may need just a little bit of oil for a pre-wash. Enough to add a little bit of shine - but no more.

Hair gets crunchy or stiff or brittle with coconut oil (or another oil)?
I'm in this group. Some people get crunchy or brittle hair or rigid hair from coconut oil with it's unusual fatty acid profile and saturated fat content. My solution is to blend coconut oil with other oils or to use a different oil like sunflower oil or babassu oil. Just about any oil can disagree with somebody's hair and create an unpleasant result. This post describes that in more detail.

How much to use and how long to leave on?
Some people need to use enough oil to make their hair feel oily. Sometimes you only need use enough to add a hint of sheen to your hair. If your hair doesn't seem to soak up lots of products and oils/conditioners - err on the side of using less oil. Concentrate on areas that are exposed to the elements - the ends and the top layer of hair. If using a lot of oil doesn't work, try using less or vice versa. If you are using a hair-penetrating oil to help protect your hair from swelling and drying out when washed - leave the oil on for 4 to 8 hours or longer before washing. Most oils are better left on for a little while when you have the time. Hair-penetrating oils need time to "soak in" deeply and other oils can use some extra time to spread throughout your hair and seep in around broken cuticles.

To heat or not to heat:
Oils become more fluid with heat and less fluid with cold. Some heat will help oils spread throughout your hair evenly. Gently heat also increases porosity slightly so that oils can move around and under cuticles more readily.
How to provide gentle heat without drying your hair? Don't blast your oiled hair with a hot hair dryer, that will probably be more dehydrating than helpful. Instead, wrap your hair with a plastic cap or plastic bag and put on a warm hat, wrap your hair with a warmed wet towel, sit under a hooded dryer or use a hair dryer on a temperature that is comfortable to your skin.

Application tip for people who are wary of oils: To use mere drops of oil, put 1-2 or 3 drops in your palm and rub your palms together vigorously. There will be a hint of shine and oil on your hands. Smooth (stroke with the hair between the palms) over the ends of your hair and the top layer. If all the shine has left your hands, add another drop of oil.

Don't write off oils forever because they don't work for you in one way. Try other approaches!

If you want the oil to penetrate your hair (assuming you've used some amount of hair-penetrating oils), leave it on for anywhere from 30 minutes to 4 or 8 or 12 hours or an entire day. If you take morning showers - apply it the night before (as long as you don't have any itchy or flaky scalp problems). If you take night showers - just wear it in your hair all day under a styling product or tied back and up.

You need to experiment with time too. Maybe you have the best results from a longer or shorter time with the oil on your hair. Just because the research says the best results were achieved from leaving coconut oil on your hair for 8-12 hours does not mean you will like that result in your hair! If you have chronic itchy scalp problems, you are better off not having excess oils on your poor scalp overnight.

Washing out:
Sometimes you need to wash twice to remove excess oil if you've used a lot, but that means you used too much oil. I do that with a dilute shampoo the second wash so removing the oil doesn't do more harm than good.

Some people don't need to use shampoo at all, using a clay cleanser or conditioner-wash (co-wash) - this works best if you already know how  much oil to use.

Ideally, you want a balance between using enough oil to give you a good result without having to use a large handful of shampoo to de-grease your hair.

How often to use:
Once you find an oil and an amount of oil and a length of treatment that works for you; use the oil treatment as often as fits your hair's needs.

If your hair always feels dry and/or inflexible by wash-day, you might use an oil pre-wash every time you wash. If that starts to weigh your hair down or leaves it feeling unpleasant, use it less often or change the amount of oil you used or length of time you left it on.

If you have a specific result you achieve from an oil pre-wash, do an oil pre-wash when your hair loses the benefits of the last oil pre-wash.

If your hair is seriously dehydrated from a chemical treatment (coloring, highlighting, perms, relaxing) or from a lot of swimming or time in the sun or dry wind - that's a great time for an oil pre-wash.

If your hair tends to get too flyaway, that's time for an oil pre-wash.

Noticing more tangling than usual? When was the last time you did an oil pre-wash?

Planning to do a protein treatment on coarse hair? Oil pre-wash before you use the protein.

Once you know how to make oil pre-washes work for you, your hair's behavior, feel and appearance will tell you when you need one.

If your hair ends up limp or too heavy after an oil pre-shampoo, it may have been too soon, or the wrong oil, or too much, or left on too long...

Won't this weigh my curls/waves/straight hair down?  No! Not if you do it right. Getting it right takes some practice. If you find that oil treatments give your curly or wavy hair nice definition (or make your straight hair less flyaway), but also make it lose its bounce - follow up an oil treatment with a protein-containing product to put the bounce back. Assuming your hair gets along with protein. Oils soften, protein supports.

Does this moisturize your hair? Technically no - oils are free of moisture (water) but oil pre-wash treatments can help your hair stay better moisturized (better hydrated), here's how: Hair-penetrating oils make normal porosity hair or porous hair or hair with porous ends get through wetting and washing without swelling in water and becoming dehydrated. If hair is not dehydrated - then what is it? Hydrated! Hooray for cheap and easy solutions.

Take home message: Oil pre-shampoo treatments are a great way to keep your hair hydrated (moisturized) throughout the washing process! It can add weight to help with frizz and keep curls or waves defined and straight hair nice and swing-y.

By choosing your oils to suit your hair, the time the oil is on your hair, the amount of oil you apply, and how you remove it you can create a multitude of different effects in your hair and hopefully one of them will be right for you.


Thursday, March 6, 2014

Managing Elasticity and Porosity in Hair

Managing Elasticity and Porosity: "How To" and a little of the science behind it.

Elasticity is a hair character or property that overlaps with porosity. Human hair is elastic - it stretches a little. It stretches a bit more when wet than when dry when it is well cared for. If we over-stretch our hair, it will be damaged. But hair that stretches rather than breaks is a good thing because it's still there to protect our heads.©Science-y Hair Blog 2014

When hair is dehydrated, it loses it's elasticity, its "stretch." Think of leather or rubber or wood left in the sun and wind for a long time. It becomes dehydrated, loses it's flexibility and becomes brittle.

When hair is porous, it loses water more rapidly than is good for it. Hair can be porous because it has been out under the sun a lot, as a result of frequent washing or wetting or lots of brushing, from hair dye or highlights or swimming pools or chemical relaxers or permanent waves or high heat styling, from daily wear and tear or abrasive styling products.

If hair loses water too quickly, it becomes dehydrated. Dehydrated hair is less elastic. Elasticity, porosity and your regional weather are closely related. Even the healthiest of hair gets dehydrated when the air is very dry.

We need to define hydrated hair. Hydration for this purpose means containing adequate water. Hair is more hydrated when the air around it is humid because hair takes up water from the air around it. Hair is less hydrated when the air is very dry.

Porosity works into elasticity and hydration thus: The more "weathered" your hair is as a result of length (more time exposed to the elements), sunlight exposure, mechanical damage (brushing, styling) heat exposure, chemical exposure (peroxide, ammonia, pool chlorine, salt, acids and alkalis), the more porous is probably is. Especially on the ends.©Science-y Hair Blog 2014

Porous hair readily gains and loses water to the air around it because it is no longer protected by a tight seal of cuticles.

Because porous hair hydrates and dehydrates easily, it is difficult to maintain good elasticity. It is simply too weathered.©Science-y Hair Blog 2014

Elasticity in all hair helps prevent breakage when hair is manipulated - detangled, styled, slept on. Good elasticity in wavy and curly and coily hair helps support a strong wave pattern that returns when manipulated. Elasticity is part of the equation that helps reduce breakage.

One thing I have seen in the process of doing hair analysis is that hair often has normal elasticity when dry, but low elasticity when wet. Most of us know that wet hair is more fragile because it stretches more and because has extra friction between the wet strands. But I was surprised by this result. So I tested some people's hair I know to be very healthy and well cared for and got a "normal" result. I'm finding that low wet elasticity and normal dry elasticity correlate with hair that needs extra help staying hydrated - keeping the right amount of water in the hair.

So how do we keep our hair hydrated? Here are some simple ways to keep your hair hydrated to improve elasticity and manage porosity. It's not difficult to understand when you know some of the science behind it and when you pay close attention to your hair's response to these things. Nothing matters more for hair care than paying attention to how your hair responds!

1) Prevent swelling and dehydration and friction that occurs in wet hair and during washing.

Your hair has its cuticle layer which appears like 4 to11 layers of thin fingernails. The cuticles overlap like shingles or tiles on a roof - keeping water out when they are well intact. Cuticles are linked to each other, making this entire outer "cuticle shell" brittle. It really is like shingles on a roof - it can cover and even turn corners on hair - but it cannot increase in girth and still maintain integrity. 

Cuticle shown in yellow, endocuticle in blue,
cortex in red.


Turquoise arrows at left show the direction
of force as the endocuticle swells in water.
























The layer beneath your cuticle, the endocuticle can swell a lot in water. If your hair is all lower porosity - the water doesn't get to this layer very easily. But when and where your hair is normal porosity to porous, water can get to this layer and it swells with water. The stress of hair-washing comes from the swelling layer beneath a non-swelling layer. As the expandable endocuticle swells beneath the cuticles, it increases in girth and exerts force outward, on the cuticle shell. As a result, cuticles are strained and stand away from the hair. In this state, they are more easily broken off. And so you have protein loss resulting from broken cuticles! Cuticles in this vulnerable position break from rubbing on other hairs, from wet combing or detangling while wet.
This is a porous area in a hair in water. The cuticles
are pushed out from force beneath as the endocuticle
swells with water. In this position, the cuticles are
more vulnerable to chipping and breakage which
causes loss of protein from the hair and further
increases porosity.



I'll add that shampoos which are too strong because they contain strong detergents or because they contain too high a concentration of detergent, and often acids like vinegar and bases like baking soda or soap bars tend to make hair swell more rapidly than plain water. All the more reason to pre-treat your hair!
This is a porous hair swelling rapidly in baking soda
solution. Not all hair reacts this violently.


How to prevent this:

- Pre-shampoo penetrating oil treatments
or
- Pre-shampoo conditioner application

Of these two options, the pre-shampoo penetrating oil treatment is the best-studied to address the swelling and protein loss and the "waterlogging" of too much swelling in water. Coconut oil has the best record for addressing these problems effectively, especially in bleached and damaged hair. But other oils may be similarly or adequately effective if coconut oil is too heavy for your hair or irritates your skin.

Leave a pre-shampoo oil treatment on for at least a few hours. 8 hours is the amount of time used in the study I'm citing below. Read more at the end of this post to find out how a pre-shampoo oil treatment works to protect your hair from damage during washing.

Conditioner before washing doesn't deeply protect the hair from swelling, but it does protect the hair from some of the water hitting it and occupy the detergent in a shampoo.  Cetrimonium bromide is an exception, it has been demonstrated to penetrate beyond the cuticles.

2) Prevent water loss from hair the rest of the time.
There are 2 ways you can do this, and you can do both at the same time, it involves products left in and on the hair.©Science-y Hair Blog 2014

A)  Water-soluble (non-oily) films that are flexible, invisible and yet water-protecting
B)  Water-insoluble (oily) films that slow water loss because they are not penetrable by water - oils and leave-in conditioners

Water soluble films can be formed by proteins, plant gums like flaxseed or okra, celluloses, pectin or carbohydrates, panthenol, hydroxypropyltrimonium honey. If you were to spread these on your skin, they would dry to a clear film. They would not be impenetrable to water - for example if you sweat, your sweat would pass through and also wet the film. These films act as a barrier to excessive water loss. Hydrolyzed proteins are water-loving and slow the evaporation of water from your (dry) hair. Not everybody's hair does well with proteins, but there are non-protein options in that list. This post has more about whose hair may do better with protein.©Science-y Hair Blog 2014

Water-insoluble films are provided by leave-in conditioners and oils you use on your hair. Oils on damp hair and leave-in conditioners on damp hair form a waterproof barrier to keep water from escaping too quickly. If your hair can tolerate oil without getting limp or greasy - oils can seal in the moisture on your hair and slow that moisture's escape into the air around it.

Oil on dry hair? That doesn't hydrate. That softens. It lubricates. Oil is water-free - so it can't hydrate or moisturize (not literally, anyway) and that's okay because hair there's a lot more to hair care than water.

3) Protect the hair to prevent water loss
Don't use high heat. Or at least not without a heat protectant.
Protect your hair from the full sun if you're out for a long time.
Protect your hair from dry, windy weather - wear a scarf or a hat you can pull your hair into. Tie your hair back if it is long so it does not blow around and use a little leave-in conditioner on it as you tie it back.©Science-y Hair Blog 2014

4) Deep treat
Protein treatments for people whose hair appreciates (or tolerates) protein
Deep conditioning for people whose hair needs extra softening and more flexibility

When you use protein or intense conditioner or both wither left on for 5-30 minutes with heat, more of the active ingredients interact with your hair and remain on your hair for a better result. Here is a link to Part I of a 2-part post about deep conditioning.

How does a coconut oil pre-wash do this? Coconut oil has been shown (using ridiculously expensive equipment) to penetrate beyond the cuticles thanks to its triglyceride content and small fatty acids. Coconut oil is attracted to the inner part of your hair. Coconut oil has a couple different effects - the first effect is not unique to coconut oil.
1) Blocks water from getting into the hair - like most oils do.
2) During washing, some coconut oil gets into the hair fiber as it is being washed. Because oil repels water, when it is introduced to the interior of the hair (which ordinarily attracts water), it makes the inside of the hair water-repellant so it swells less.
Less swelling means the cuticles won't be lifted up where they are easily broken off which means that all those proteins that belong to the cuticle won't be lost, your hair won't be waterlogged and I should add that your hair will feel soft and lovely after you wash it.

The effect is more obvious on damaged, porous and especially bleached hair (highlights, lightener, permanent color) and less obvious on lower porosity hair.

The effect of coconut oil is less if its applied to hair after washing than if applied as a pre-shampoo treatment.

What if I hate coconut oil? 
Avocado, sunflowerPalm kernel oil, babassu oil, and Ucuuba butter penetrate the hair and would be good substitutes for coconut oil. 
I use an oil mixture in my lower porosity hair and as far as I'm concerned, it's better in my hair than straight coconut oil which is too heavy for me and makes my hair a little rigid. Here is a link to a post about making pre-shampoo oil treatments work for your hair. 
©Science-y Hair Blog 2014
In this post, olive oil did not protect the hair as long in chlorinated water as coconut oil and I suspect that is because the polar coconut oil is attracted to the hair proteins (it can get into the hair) in addition to forming an oil film over the hair surface.

You'll notice that conditioner protected the hair from the chlorinated water very well too - so if oil is just not your thing - a pre-shampoo application of conditioner, known colloquially as "condition-wash-condition" might do the trick.





AARTI S. RELE and R. B. MOHILE, 2003
Effect of mineral oil, sunflower oil, and coconut oil on prevention of hair damage. Journal of Cosmetic Science, 54, 175-192