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.