Beauty

This could be the reason your hair products aren't working

Your hair could have high or low porosity—here's why it matters.

A woman sitting at a vanity brushing product through her hair Credit: Getty Images / Prostock-Studio

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Achieving healthy hair is a combination of many factors that include knowing your hair type (from straight to kinky) and texture (from fine to coarse), and also its porosity. This factor refers to how porous, or potentially absorbent, the individual strands of your hair are or are not. Knowing your hair's porosity helps you to better understand what type of products you should be using, how to properly wash your hair, and even the limitations to styling your hair that you may encounter. Porosity is mainly determined by genetics but, as scientific as it sounds, it's easy to figure out and alter your hair care routine around.

With a few simple steps, you’ll be on your way to understanding how to treat your hair better and achieve your hair goals, whether it be sleek straight locks or defined curls. We spoke to Tiffany Ramirez, a hair stylist at Amaris New Look Salon in Queens, New York, to break down the three types of hair porosity and how to best care for hair within each type.

What is hair porosity?

hair cuticles
Credit: Getty Images / Art4stock

Hair cuticles are microscopic flexible layers that serve as a protective seal for the hair strand.

Hair porosity is your hair’s ability to absorb and retain moisture, according to Ramirez, and it’s determined by the makeup of your hair cuticle, i.e., the outermost layer of your hair shaft. Hair cuticles are microscopic, flexible layers that serve as a protective seal over the hair shaft and determine how much water, moisture, and oil can penetrate the hair strand, Ramirez says. Porosity is divided into three categories: normal (or medium), low, and high.

For your hair to stay healthy and strong, it’s important to keep a good balance of moisture and protein. Too much or too little of these things can leave your hair feeling damaged, weighed down, or dried out. Luckily, you can determine your hair porosity at home and learn how to better take care of your hair depending on what category your hair falls in.

How to test hair porosity

porosity test
Credit: Getty Images / Art4stock

Filling a cup with water and dropping a single strand of hair into the glass can help determine your hair porosity.

You’ll want to perform this assessment on freshly washed hair that is free of product and oil buildup so that you’ll get the most accurate results. To start, fill a transparent cup with water and dip a single strand of hair into the glass. You can get this strand of hair from your brush or comb after running it through your clean hair, or use one still attached your head if you have long enough locks. Let the strand soak for a few minutes and watch if the hair sinks, floats to the top, or floats in the middle. This isn't an exact science, but here's what the outcome tells you:

  • Normal/medium porosity: If the strand floats in the middle of the glass, you likely have normal porosity hair.

  • Low porosity: If the hair strand floats at the top of the water, you likely have low porosity hair.

  • High porosity: If the hair strand sinks to the bottom of the glass almost instantly, you likely have high porosity hair.

Why does hair porosity matter?

Normal or medium porosity hair is the most common, and it means that the layers of hair cuticle—which look similar to a pine cone’s layered scales—aren’t too closed or too lifted. Your hair cuticles are spaced "normally" and let moisture pass through and absorb quickly when washing or styling the hair. If you have this type of porosity, moisture can penetrate the hair shaft easily as well as retain moisture for longer periods of time.

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It’s easy to achieve and hold various different hairstyles for hours if you have hair with normal porosity. This porosity type also usually takes to hair dye well because it’s porous enough to allow the color to absorb in and hold it and the hair fully dries in a reasonable amount of time. For those with medium porosity curly hair, this means that your curls tend to look healthy, springy, and voluminous without the need for excessive products or gels, Ramirez says. Straight or curly, these types of locks also stay tame with little frizz and hold moisture well throughout the day to avoid looking dry.

Heat damage and other frequent chemical processes can cause normal porosity hair to change to either low or high porosity over time, Ramirez says. If the hair floats closer to the top, it leans closer to low porosity hair and if it floats closer to the bottom, it can possess some qualities of high porosity hair, which explains the need for the difference in product needs.

To maintain healthy hair, Ramirez recommends maintaining a balance of moisture-rich and protein-filled products by using a moisturizing shampoo, like the Olaplex No. 4 Bond Maintenance Shampoo and doing a bi-weekly intensive deep conditioning with a product like the Briogeo Don’t Despair, Repair Deep Conditioning Mask.

What is high porosity hair?

High porosity hair means that the hair cuticles are raised and open, and therefore the hair loses moisture faster than normal, according to Ramirez. The best way to think about high porosity hair is to think about a sponge with holes in it—those holes represent the raised and open hair cuticles. This also means that high porosity hair can be prone to frizz, tangles, and breakage. High porosity hair is very absorbent, but it struggles to retain moisture. For that reason, Ramirez recommends using protein-based products that help strengthen the hair—look for ingredients like keratin, collagen, amino acids, or the word "protein" on the label. Also, applying a hot oil hair treatment every other week can help to seal the gaps in the hair cuticle and strengthen the hair shaft over time, reducing the amount of moisture loss.

High porosity hair is often the result of damage caused by color or chemical treatments, according to Ramirez. If you have this porosity type and treated hair, you should use leave-in conditioners and sealers, like butters and creams, to lock moisture into the hair. Always apply heat protectant before using hot tools on your hair because it can help prevent more damage to the hair shaft. Wash and rinse with lukewarm or cool water instead of hot (which lifts the cuticle) to keep the hair cuticle as closed as possible to retain moisture.

Styling high porosity hair can be difficult because this type does not hold on to styles as well or for as long as normal porosity does. It’s best to stick to styles that closely mimic your natural hair shape for longevity, Ramirez says. She recommends using an extra-strength holding spray if you’re determined to try or achieve a look that's further away from your natural shape.

To help your high porosity hair retain moisture and seal the hair cuticle, try Aphogee’s two step protein treatment and balancing moisturizer, which claims to stop breakage and repair damaged or over-processed hair.

What is low porosity hair?

Unlike high porosity hair, the cuticles on low porosity are close together and closed, meaning the strands practically repel water, oils, and other moisturizing products. Because the cuticles are close and tightly bound, it’s harder for products to absorb into the hair, which causes oils, gels, and creams to sit on top of the hair strand and make it feel weighed down or wet. This leads to product buildup and greasy- or oily-looking hair, so more frequent washing to keep the scalp and hair clean is important. Ramirez recommends applying styling products in the shower with hair still saturated with lukewarm or cool water as they’ll be better absorbed rather than letting the hair start to dampen or dry.

Low porosity hair can appear limp and greasy, and take hours or even all day to completely air-dry. If you have hair with this porosity type, you may notice that it takes a few minutes to get the hair fully saturated when washing or while being placed underwater because it’s not as absorbent.

Ramirez recommends washing at least once a week with a clarifying shampoo that’ll remove any product buildup and residue in the hair, like Ouai’s Detox Shampoo and using products that have lightweight formulas so as to not weigh the hair down. She also recommends you use a steamer, like the Kingsteam 2 in 1 Hair Steamer, to help open up the hair cuticle and allow moisturizing products to be absorbed into the hair especially before applying a deep conditioner.

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