Last Updated on April 6, 2023 by Verna Meachum

Do you know what your hair porosity is? This little-known hair characteristic can play a big role in how well your hair retains moisture.

Knowing your hair porosity is key to understanding your hair’s unique needs and taking steps to keep it healthy.

What if your hair has changed since last year because of variations in color, styling habits, medication intake, and climate conditions?

Would you know how to adjust your hair care routine to keep it looking, feeling, and behaving its best?

That’s why it’s important to understand the concept of hair porosity.

This article will go in-depth on the aspects that influence your hair porosity, how you can identify yours, and some tips for taking care of it.

What is Hair Porosity?

Hair porosity is a technical term that defines the hair’s macroscopic appearance and microscopic condition.

The word “Porosity” is derived from “pore” and describes the pore size, volume, and density on the hair shaft. 

Cuticles are the outermost layer of the hair shaft while the cortex and medulla are the inner structural units of the hair fiber.

Hair fiber appears as a compact cylinder where cuticles and cortex are firmly cemented. The cuticle layer contains tiny pores through which water molecules, active conditioning ingredients, coloring molecules, and polymers penetrate and go deep inside the hair fiber.

All hair is porous. The degree of porosity is an indication of how damaged your hair is. The more porous your hair is, the more damaged it is.

Factors like chemical treatments, UV radiation, brushing hair excessively or too harshly, etc. can cause hair cuticles to become damaged.

Depending on the severity of the damage, the inner cortical components can be exposed leading to an increase in pore size, and pore volume, as well as a significant increase in the number of pores (pore density) over the hair shaft.

Why Porosity Matters

We should never subscribe to a one-size-fits-all mentality when it comes to our hair, as no two types are alike.

Everyone’s hair requires special attention and individualized care to look and feel their best – but how does one know what kind of products are needed?

The answer lies in understanding your own hair’s porosity!

Porosity matters as it is the first indication of your hair quality. Poor porosity leads to a lack of hair health, luster, shine, texture, and body.

Those with porous hair are unfortunately familiar with copious amounts of unruliness, as their strands often resist styling and settling into the desired shape.

As you run your fingers through your hair, it feels unpleasantly rough due to cuticle loss. Consequently, this imparts a lifeless and lackluster look since less light is reflected from its rough surface.

Porosity is a crucial metric of hair quality that should be closely monitored. If the porosity level becomes too high, there can be serious consequences such as breakage during brushing and combing, leading to thinning hair.

It’s therefore essential to take steps to keep your porosity in check and address any issues quickly before it becomes worse.

What are the Different Porosity Types and Causes?

Hair experts have characterized hair fibers into three distinct levels of porosity.

• Low Porosity Hair 
• Medium Porosity Hair
• High Porosity Hair

The characterization varies with increasing degrees of porosity. Hair porosity is not static; it shifts whenever hair texture and structure are modified or harmed.

Generally, the more damage your hair has endured, the higher its porosity becomes.

Low Porosity Hair

Possessing small openings and pore sizes, hair with low porosity is typically virgin and not chemically treated; it’s healthy hair.

Low porosity hair does not absorb moisture easily due to its dense cuticles that lay flat. Additionally, low-porosity hair repels water better than other types of hair.

Low-porosity hair possesses a minimal degree of porosity and can still experience damage from prolonged exposure to UV light, the natural aging process, aggressive combing/brushing, rough handling of hair, etc.

As your hair becomes longer, the ends become more porous due to their age while the roots remain in good condition as they are newly grown.

Medium Porosity Hair

Medium porosity hair does not suffer from a high degree of cuticle damage, which is often caused by continuous heat styling, perming, and over-brushing.

It sits between low and high porosity and is characterized by medium-sized cuticle openings and a medium amount of pores. It easily retains and absorbs water well. 

High Porosity Hair

When hair is damaged, it develops tiny cracks in its protein structure that eventually lead to pores. These visible signs of damage are an indication that the hair has been compromised.

Some characteristic features or indicators of porous hair are:

• As you glide your fingers across the hair, its rough texture is undeniable.
• Hair absorbs moisture quickly and dries off just as quickly.
• Frizzy.
• Difficulty in combing, styling, and manageability.
• Fluffy and poofy.

Hair that is characterized as high porosity features many open pores with a larger size, caused by protein loss which results in large empty spaces within the strands.^1,2,3 

High porosity hair has raised, broken, (sometimes missing) cuticles, which makes it easy to absorb water and lose it just as quickly. Thus, making it difficult to maintain moisture levels, leading to frizzy, dry brittle hair.

Depending on the severity of the damage, the inner cortex materials can be fully exposed to the outer environment.

Additionally, if the hair is too compromised to save with no cuticle left on the strands, the hair is considered to be in a degraded state.

Degraded strands have completely unattached cuticles that can cause excessive breakage and shedding. If your hair’s porosity is classified as degraded, the only way to repair it is by cutting off the damaged ends and starting anew.

Factors that Can Increase Porosity

Hair is susceptible to a wide range of harm. A variety of factors can considerably alter the porosity, some more drastically than others.

Ways to Figure Out Hair Porosity

High-tech experimental protocols are used by hair scientists to accurately assess the porosity of hair.

These test procedures thoroughly analyze single hair fibers to assess both the quality and quantity of the sample, resulting in a numerical value that reflects its exact porosity level.^4,5,6

Unfortunately, we consumers lack access to these advanced machines and need an easy method in which to measure our hair’s porosity- whether at a salon or within the comfort of our home.

To that end, hair experts have come up with a range of simple assessments to evaluate our hair porosity that can be done at home.

In comparison to other methods discussed on the web, floating tests are more scientifically reliable and better reflect actual assessment results.

Floating Test

Characteristics of High Porosity, Medium Porosity, and Low Porosity

With its distinct properties, each porosity level can easily be distinguished.

Low Porosity	Medium Porosity	High Porosity
Cuticle layer intact.	Partially compromised.	Cuticle layer is compromised (or may be eroded).
Hair in good condition (healthy).	Relatively less damaged.	Extremely damaged.
Low hair breakage upon applying pressure when combing or brushing.	Hair does not break easily.	Lots of hair breakage.
Low frizz.	Moderate frizz.	Lots of frizz.
Hair feels good and only shows roughness toward the ends of hair.	Low to moderate roughness.	Extremely rough and dry.
Hair is not greatly affected by extreme humidity fluctuactions.	Moderate response to high humidity conditions.	High uptake of moisture from its surroundings.
Hair behave as normal during hair coloring and color appears uniform.	Moderate dye uptake during hair coloring.	High uptake of coloring molecules or pigments during hair coloring application. Color does not appear smooth and uniform.

Can Your Porosity Level Change?

Yes, hair can transition from low-porosity to high-porosity and the other way around. This transformation can happen with time or when affected by external elements such as heat styling tools, chemical treatments, and more.

Low-Porosity to High-Porosity: An Increase in Porosity Level

Low-porosity hair is virgin and non-chemically treated. When exposed to harsh chemicals such as bleach or permanent dye, hair can become stripped of its proteins and suffer damage. This leaves the hair with an increased porosity level.

During these harsh oxidation processes, the proteins in hair react and amino acids are oxidized. These oxidized protein byproducts are soluble in water and will be washed away with a regular shampoo session.

Ultimately, hair loses its proteins and cuticles, leading to an increase in pore size with greater pore density. As a result, low-porosity hair evolves into high-porosity hair.

High-Porosity to Medium-Porosity: A Decrease in Porosity Level

With proper hair care, high porosity levels can be reduced and your hair will recover its original sheen, strength, and healthy appearance.

This requires repeated application of hydrating, conditioning, and fiber-strengthening formulations. These fiber reconstructor formulations comprise vegetable proteins, keratins, and micro-polymer molecules.

Proteins are known and scientifically proven to restore the hair’s mechanical strength and recover its natural gloss.⁷

Cationic conditioning polymers can also improve fiber quality and combat their high porosity.

Consistently using a proper hair care regimen can improve fiber porosity and eventually can convert high-porosity hair to low (medium)-porosity hair. 

I am a living example of this. My hair used to be severely damaged and highly porous due to flat irons, bleaching, and other chemical treatments.

But, after using a combination of the following treatments, my porosity level was back on track!

• protein treatments
• oils
• deep conditioners
• rice water rinse
• apple cider vinegar rinse, etc.

Now my curls are much healthier than before – all thanks to these incredible treatments.

Can You Change Your Hair Porosity?

Yes, you can change your hair porosity with a combination of treatments and a consistent hair care routine. It’s possible to transition from damaged hair to healthier hair.

Here are some tips to help you manage your hair porosity:

Tips for low-porosity hair

1) It can be alluring to layer on several hair products in an attempt to moisturize low-porosity hair; however, this approach may not always provide the best results. For those with low porosity hair, the tightly-packed cuticles may not be able to absorb large amounts of product. As a result, this can lead to an excess build-up of products in your hair.

2) Look for ingredients that can easily penetrate your hair and nourish it from within.

3) To restore moisture to your hair, search for products that are specifically formulated for low-porosity hair.

Such as:

• shampoos
• conditioners
• leave in conditioners
• deep conditioners

4) Don’t be afraid to use protein! Most shy away from proteins and don’t know which type of protein to use, but properly balanced proteins can help smooth the cuticle and prevent breakage.

5) Maximize your deep conditioning potential with the help of heat! Heat (i.e. steamers) can lift the hair cuticles, giving it full access to nourishment from your conditioner.

For high porosity hair

1) Blending a synergistic selection of protein-rich and moisturizing products will yield the best results.

2) To restore moisture to your hair, search for products that are specifically formulated for high-porosity hair.

Such as:

• shampoos
• leave in conditioners
• oils and butter
• deep conditioners

3) High porosity hair has the unique advantage of being able to hold multiple layers of product simultaneously for added nourishment and moisture.

4) Supplement protein treatments to reinforce the cuticles, whenever necessary.

5) Rinse your hair with cold water to help the cuticles lay flat.

6) When it comes to moisturizing high-porosity hair, it is paramount to incorporate deep conditioning treatments into your routine to keep it healthy.

7)It is essential to be gentle when detangling hair since it tends to be more fragile.

FAQs

Is low or high-porosity hair better?

Porosity is just an indication of how damaged your hair is. The more porous your hair is, the more damaged it is.

If you have low porosity hair, it means the cuticle layer is lying flat and it is healthy. There is no need to fix what isn’t broken. High porosity hair has some damage that has caused the cuticle layer to be lifted or raised.

It is not about being better, but knowing how to take care of the hair you have. Don’t be fooled by myths that low-porosity or medium-porosity hair is better than other types, or that having high-porosity hair is negative.

Get to know your unique texture and what it needs to thrive! No matter which type of hair you have – as long as you take care of it, it will flourish!

Summary

Hair porosity is a frequent issue for both consumers and hair care experts alike. By pushing our hair too far with extreme grooming techniques or damaging chemical treatments, protein loss causes the shafts to become more porous over time – an unenviable result of these practices.

Porosity has three unique magnitudes, each bringing its own set of difficulties for hair consumers when it comes to maintenance. This emphasizes the necessity for a personalized regimen tailored specifically to accommodate each level of porosity.

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References

1. Lee, Y.; Kim, Y.-D.; Pi, L.-q.; Lee, S. Y.; Hong, H.; Lee, W.-S., Comparison of hair shaft damage after chemical treatment in Asian, White European, and African hair. Int. J. Dermatol. 2013, n/a-n/a.

2. Jeong, M.-S.; Lee, C.-M.; Jeong, W.-J.; Kim, S.-J.; Lee, K.-Y., Significant damage of the skin and hair following hair bleaching. The Journal of Dermatology 2010, 37 (10), 882-887.

3. Scanavez, C.; Silveira, M.; Joekes, I., Human hair: color changes caused by daily care damages on ultra-structure. Colloid Surf. B-Biointerfaces 2003, 28 (1), 39-52.

4. Yuen, C.; Kan, C.; Cheng, S., Evaluation of keratin fibre damages. Fibers and Polymers 2007, 8 (4), 414-420.

5. Hessefort, Y. Z.; Holland, B. T.; Cloud, R. W., True porosity measurement of hair: a new way to study hair damage mechanisms. J. Cosmet. Sci. 2008, 59 (4), 303.

6. Syed, A. N.; Ayoub, H., Correlating porosity and tensile strength of chemically modified hair. Cosmetics and toiletries 2002, 117 (11), 57-64.

7. Neudahl, G. A., Proteins for conditioning hair and skin. In Conditioning Agents for Hair and Skin, Schueller, R.; Romanowski, P., Eds. Taylor & Francis: 1999; pp 139-166.