Hair Porosity - 4C Coarse Hair Guide

Why hair porosity is important
Finding the right product like the best edge control for coarse hair and routine that for your hair can be a hit and miss. Curl typing will only get you so far, which leaves people looking for a more reliable approach to finding what works. For an increasing amount of people, that approach is hair porosity testing.

What is porosity?
So here's a quick primer on how hair porosity is defined in the natural hair community. (Hair scientists and hairdressers traditionally have a different concept).

But on hair that's truly high porosity, whether by nature or by damage, you're always going to have the advantage of hair that's easy to moisturise -- and the work of going that extra mile to lock moisture in.

For dry high porosity hair, your focus isn't getting moisture to penetrate your hair; it already does that easily. Instead, you need to focus on insulating your hair to reduce moisture loss.

Insulating goes a little further than sealing; it means using different layers of water-loving and hydrophobic products to trap moisture inside your hair.

This process starts with your conditioning step: you can blend super hydrating treatments like Baba de Caracol with other powerful conditioners that act more at a surface level like Silicon Mix Treatment.

Porosity for naturalistas is all about how much (water or product) your hair can absorb. Generally, people use these three categories of hair porosity:

High porosity hair takes in (and loses) moisture the fastest
Low porosity hair takes in moisture more slowly and loses it slowly too
Medium or 'normal' porosity hair is somewhere in between.​

​What causes porosity in hair?
Your hair's porosity is the result of several factors: how compact your cuticle layers are, how raised your cuticle is (naturally or through damage), and how intact the surface of your hair is.


High porosity or porous hair will usually have one or more of the following: a less than compact strand, a higher cuticle scale angle, or a damaged surface, full of 'pores', often with the outermost layer missing.

​So whether it came out of the scalp with its cuticles at a slightly higher angle, or got that way via a texturizer or some bleach, a lot of people have hair that takes in moisture fast and loses it fast too.

To naturals, both these types of hair count as "high porosity hair."

High porosity hair vs hair that's just dry: How to tell the difference
If you don't have high porosity hair and your hair is just dry for one of these three reasons, how would you know? Does low porosity hair need protein?

You might have to repeat the process a few times to know for sure, but it's super simple. The first step is to clarify your hair: Use a laureth sulfate shampoo, use atrActiva Anti-Stress Shampoo to remove the buildup that is stealing all your moisture at the strand level. Sulfate-free options won't work for this.

Deep-cleansing like this will take care of dryness due to buildup from drying oils or other residue.

Do I have high porosity hair?
If your hair sucks up moisture like there's no tomorrow, only for it to disappear within the hour, you might be thinking you're firmly in this high porosity category. But you might not be. Here's why:

Reason #1: Castor oil for low porosity isn't the same as absorbency
People in the natural hair community often use the two terms interchangeably, but while they're definitely connected, they're not the same.

Difference between High and Low Porosity
High porosity hair means your hair takes in moisture just as easily as it lets go of it.
Low porosity means your hair has a difficult time taking in moisture.
Porosity can be affected by different things, like chemical damage, but that’s not the only factor: people just have different hair, including different porosity levels.

The lie is that you can easily find the porosity of your by simply doing the water test, which is not an accurate representation of how your hair takes in moisture.

hair porosity test
First of all, there are so many variables involved with this porosity test. Our hair naturally has oils in it, and oil floats on water. We may also have a lot of products in our hair, which doesn’t accurately show our porosity if we take a strand of hair with tons of product.

Even if you wash your hair and take a clean strand, what is the certainty your hair is free of oils?

When it comes to porosity, you should know:

How to Test Your Porosity?
You can evaluate your own hair’s porosity level without taking out any strands or setting aside two cups of water.

Both of these sponges are dry to begin with, but then you spray a large amount water onto one of them.

After that, you put each of those sponges into identical bowls, filled with exactly the same amount of water, and let them soak for the same amount of time.  You may also want to know does porous hair hold color.

What happens when you pull them out?

​The sponge which was already partially hydrated — the one you sprayed -- won't have taken in that much water.

That's no surprise; it was already wet, so there wouldn't be much space left inside to hold more water. But the dry sponge? It might soak up all the water in the bowl.

This difference in absorption happens even though both sponges naturally have the same porosity.

Sponge and spray can illustrating high porosity vs low porosity and hair dryness.
Wetting a sponge makes it less absorbent but doesn't change its porosity. Image by Tumisu.

​It's exactly the same with hair. Say you have a hair twin whose hair has roughly the same porosity as your hair. If you keep yours moisturised and she leaves hers desert-dry most of the time, her hair is going to seem like it's more porous than yours.

Square One
Let’s start from square one – what does porosity mean? Hair porosity refers to your hair’s natural ability to absorb moisture and product.

Medium Porosity
Medium porosity hair has little to no difficulty absorbing or retaining moisture. It tends to be relatively healthy with minimal exposure to damage from UV, chemical or heat processing.

Fun Fact: Hair starts out with a medium or low porosity level and gradually becomes more porous as damage occurs.

The best thing you can do for your strands is to have a beneficial hair regimen that focuses on hydration and low-heat styling to keep hair at a medium to low porosity level.

Tips for Hair with A Medium Porosity Level

Wash your hair regularly to keep it clean and build-up free. Since excess buildup and deep hydration aren’t a large concern for this porosity, focus on choosing products made for your hair type.

We’ve created a simple assessment that can help you to determine your hair’s porosity level and give a bit of background as to what exactly that means.

You can take our Porosity Quiz and report back to get some deeper information on porosity levels in the rest of this blog!

If you’d like to take a hands-on approach, there are a few quick tests that you can conduct yourself to determine the porosity level of your hair.

The Strand Test
Take a single strand of your hair in fingers. Starting from the bottom, run your fingers upwards to the root of the strand.

What do you feel?

Low porosity hair has a limited capacity to absorb moisture. Image by Agatha Ezepue.

If you then use products that aren't favourable to moisture absorption, like most people with low porosity hair do, you effectively bring your coarse hair strands' chances of getting moisture down to nil.

And once your hair is that dry, it can start to act thirsty, the way high porosity hair does. Whenever it gets the chance — like when you're applying leave in —​ it absorbs more moisture than you would expect.

But if your low porosity hair doesn't get enough time to take enough moisture in -- which is very likely to happen since it's so slow at absorbing stuff — guess what happens?

It'll feel dry again soon after, just like high porosity hair does.

Moisture (aka water) isn't going to stick around and wait forever for your strands to absorb it. If your hair doesn't take it in in time, it's just going to evaporate from the surface, especially if you're in a dry environment.

If the strand feels rough, bumpy or breaks - your hair has a high level of porosity.

If the strand feels smooth – your hair has a medium level of porosity.

If the strand slides easily and feels dense or hard in your fingertips – your hair has a low level of porosity.

Want a second opinion? Try this quick test, too!

The Float Test

After brushing or running fingers through your hair, remove a single strand. Fill a bowl or cup with room-temperature water and place the strand inside.

What It Means:

If the strand sinks quickly to the bottom – your hair has a high level of porosity and it may mean that you have coarse hair.

If the strand sinks slowly to the bottom – your hair has a medium level of porosity.

Hair with a high 'Moisture Debt' like this, will need to take in more moisture over time, gradually balancing its levels before its true porosity is revealed.

Which brings us to Reason #2.

Reason #2: Low porosity hair sometimes acts 'just like' high porosity hair
Low porosity hair can do the whole, "I just moisturised it and look now it's dry again!" thing very well. Contrary to popular belief, if your hair's porosity is low enough, it runs a pretty high risk of getting extremely dry -- often way drier than high porosity hair.

This happens very often on 4c hair, which tends to have extremely low porosity but is often mistaken for high porosity hair, because it too struggles to retain moisture.

Oils can often block out hydration on low porosity hair. Image by Silviarita.

​Other oils which aren't classified as drying oils can still build up on the surface of your hair and act as a barrier to hydration.

If you've ever felt like the more oil you apply, the drier your hair gets, it probably isn't because you have high porosity hair; it's more likely because the oil's blocking all the moisture out.

What if I have the type of hair that just drinks up everything?
Your hair doesn't really absorb everything. Nobody's hair does. Most of the stuff we apply to our hair never even makes it inside; that's because only ingredients with the right size and chemical structure can actually penetrate the hair's surface.

Water can make it in (with varying degrees of difficulty) but the size and shape restrictions rule out most oils and butters aside from coconut oil.

Some DIY deep conditioner for low porosity hair ingredients can penetrate the hair if you give them enough time; cetrimonium bromide is one. But most won't.
So if you're putting product on your hair and it's just disappearing, it's not all going inside your hair. Some of the water is, but the rest is just evaporating, rubbing off on your clothes, drying and flaking off, or just sitting on the surface of your hair. Even if you can't necessarily feel it on your strands. That's because many products are designed to leave you feeling like there's nothing on your hair, when there's actually a good bit of residue.

​That same residue could be tricking you into thinking your hair's high porosity when it's not.

If the strand floats – your hair has a low level of porosity.

Shower Test:

How does your hair take in water when you wash your hair? Does it easily absorb it? That would be a sign of high porosity.

Ask yourself:

Does my hair dry up easily after moisturizing? You may have high porosity hair.

Does it take a lot to absorb moisture? Once that moisture is captured, does it last for a long time though? You may have low porosity hair.

Or does my hair have none of these problems? You may have normal porosity hair.

Testing your hair porosity is almost like playing a guessing game, compared to the inaccurate test all across the Internet, but is definitely a better option to figure out how to treat your hair.

Read these too!

Damaged hair is going to be more porous than virgin hair.

There are better and more accurate measures to test the porosity of your hair. [ Learn about how to stretch natural hair after washing ]

The appeal behind this is simple: Figure out your hair's porosity and you'll know exactly what kind of products and routines work best for you. Your hair will flourish and your natural journey will be that much smoother. At least, that's the theory.