Hair Porosity Basics

It’s pretty common for a lot of wavies and curlies to focus on their curl pattern when they learn their hair stats. While it can be fun to know what your curl pattern is, it’s actually the least important factor when choosing the right products and routine for your hair.

The most important factor is the porosity. Porosity is your hair's ability to absorb and hold on to moisture. Your cuticle determines the porosity of your hair. For most people porosity is genetic, but external factors, such as damage, can change your porosity.

There are three levels of porosity: low, medium, and high. In order to determine your porosity there are three tests:

• The Slip Test: slide your fingers along a single hair, bumpy hair means high porosity, smooth means low, somewhere in between would be medium.
• The Spray Test: mist a section of your hair with water: water that beads on the strands and does not absorb means low porosity. If it absorbs immediately, high. If the water sits for a couple of minutes and then absorbs, it would be medium.
• The Float Test: this is the most common but also the most inaccurate. Drop a clean dry hair into a cup of water, if it floats, low porosity. If the hair sinks to the bottom, high. If the hair stays in the middle, medium.

Ok, so what does it mean to have low, medium, or high porosity?

Low porosity hair has a tightly closed cuticle. This prevents the hair from absorbing moisture. Typically it takes a long time for low porosity hair to get wet and a long time for it to dry. Low porosity hair is prone to build up as products don’t absorb easily either. Look for light, water-based products containing humectants (glycerine, honey, etc). Humectants pull moisture into the hair from the air, which benefits low porosity. Apply products to wet hair using heat or steam to open the cuticle. Low porosity hair is protein sensitive and typically does not react well to protein. Avoid heavy ingredients, oils, and protein.

High porosity has a wide-open cuticle. Moisture is easily absorbed but easily lost. High porosity hair generally gets wet very quickly and can also be known to dry quickly. Heavier products containing oils and butters are recommended to trap in moisture. Environmental damage as well as chemical procedures can lead to high porosity. High porosity hair likes protein but needs moisture as well. Protein pushes out moisture and if used alone can lead to dry brittle hair. Deep conditioning is recommended weekly. Avoid using excessive and high heat, which opens the cuticle and lets moisture out.

Medium porosity hair, also known as normal porosity, has a partially open cuticle. Moisture can enter but doesn’t escape easily. Medium porosity is relatively low maintenance but can be affected by heat and chemical damage. You can use a wide variety of products on medium porosity hair, but it can be prone to build up as well so be careful using heavy products. Moisture and protein treatments help but are not needed as frequently as low or high porosity hair.

Remember, curl patterns can be fun, but knowing your porosity will help you select the right products for your hair!

Want to learn more about hair porosity? You can read our hair porosity in-depth guide here.