By Hadassah Agbaps - March 06, 2020

Hi people! What's been on?

You know how you do something and one day decide to look closely at what you're doing?
Well, I decided to look closely into the "sealing" step of the LOC moisturising regimen.
Whenever I explain how to retain moisture in natural hair, I usually use the word "seal " because it kind of gives you a picture of what it does for natural hair.

Ermmm... what am I on about? Okay, let's go back to the beginning!

Natural hair is usually prone to dryness due to its structure. It gets that crunchy, haystack like feel after sometime which is unlike the soft, fluffy candy floss feel you get immediately after washing it.
To preserve or provide moisture (which is responsible for the softness), the hair is misted with water or water based leave in (L), which is "sealed" in with oil (O) which is further reinforced with hair butter /cream (C).

The science behind this method is that water and oil don't mix.
So water can't evaporate through the layer of oil. So oil kind of "seals" in the water which retains moisture... get it?

But if the oil really "seals" in water in the hair, how come the hair still gets dry again? How does the water find its way out of the oil "seal"?!
And how come your hair still gets wet on washday in spite of the oil?

If I'm really "sealing " in the water with the oil, how come I still have to moisturise again?!
Okay, granted my hair still stays moisturised for 2-3 days with the LOC method or (OLC in my case) as against less than an hour (porosity things ) but still I'm "sealing", aren't I?

Okay, so I did my research and here's the answer to that question!

In a study titled "EFFECT OF OIL FILMS ON MOISTURE VAPOUR ABSORPTION ON HUMAN HAIR ", Keis K et al used a natural oil(coconut oil) and a synthetic oil (mineral oil) to treat hair and compared the moisture loss to untreated hair. They came to these conclusions and I quote,
"Although treating hair samples with oil reduced moisture pickup, a considerable amount of moisture was still able to penetrate hair fibres...
Calculated plots show that samples (of hair ) treated with oil have a "slightly " higher moisture at low relative humidities compared to the untreated hair fibres suggesting that surface oil films and penetrated oil molecules form a diffusion barrier...
Thicker films absorbed less water vapour compared to thinner films. However, mineral oil absorbed less water than coconut oil irrespective of thickness
." Unquote!

For those not patient enough to read excerpts of the study, I'll summarise their results here.

1. Coating hair with oils doesn't necessarily "seal" in water instead they form a "temporary barrier" increasing the time it takes for water to evaporate out of the hair.

2. Synthetic oils seem to do a better job at reducing  moisture loss which is a double edged sword because they also do a better job at reducing moisture absorption which your hair still needs.
So I can say, if I want to prevent moisture in my twist outs or flatironed hair, a synthetic oil may be my best bet.

3. Natural oils also reduce moisture loss. However they do a better job than mineral oil in allowing for moisture absorption. This may be because the natural fatty acids in plant oils are more water soluble than synthetic oils. Also unlike synthetic oils that simply coat the hair, natural oils are better absorbed into the hair shaft.
So if I want to retain moisture and still allow my hair to absorb more moisture from the environment, a natural oil will be my best bet.
Personally, that's a win-win situation!

4. Coating my hair with a thicker natural oil (such as shea butter or cocoa butter) helps improve moisture retention but one coat of a synthetic oil will be sufficient.
So now we know about the moisture retention abilities of oils, which is better... synthetic or natural?

Synthetic oils include mineral oil and silicone oils such as dimethicone and amodimethicones.
Synthetic oils are not absorbed by the skin or hair. They form a coat.
Layering of synthetic oils on the hair can cause build up which can only be removed by sulphate shampoos which are drying to natural hair than their non sulphate counterparts.
So if you're going to use synthetic oils on your hair for moisture retention, please do keep a sulphate shampoo around.
I use a sulphate shampoo to get rid of build up and that's because my regimen includes cowashing with conditioners that may contain silicones and also styling products that may contain synthetic oils such as the ORS Incredibly Rich Moisturising lotion I use as a heat protectant.

Natural oils include olive oil, Shea butter, coconut oil, castor oil and so on.
They also do a good job in moisture retention when used over a water based product.
They also allow my hair to absorb water from the environment.
They do not clog pores, coat hair and are less likely to cause buildup since they are easily absorbed.
I do not need a drying sulphate shampoo to wash my hair. Sulphate free shampoo or cowash will do just fine.
However, if I want my pressed hair to last longer, then I'd better use a synthetic oil to reduce absorption which can cause my hair to revert.

So in essence, both oils has it's advantages and disadvantages and using them depends on
- Your environment
- Your hair type
- Your hair regimen
- Your understanding of their uses... this is very important which is why I usually recommend natural oils as it's less likely to cause problems for beginners.
- The availability of products in your area.
I understand how hard it is to find those good sulphate free, silicone free, all natural moisturizing  products,so this should guide you in the choice of moisture retention oils to prevent your hair from drying out.

So I'll correct myself by saying oils don't "seal" in moisture, they help "retain" moisture in your hair!
P.S. Seems like coconut oil is one of the best natural oil for moisture retention.... but that's a topic for another day!

Till then,
Live Beautifully. Naturally.

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  1. Wow.. didn't know there are thesis on natural hair and moisture retention..way to go


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