Hair Porosity…….what? This term has been thrown around by naturals but what does it really mean. There is so much information regarding this topic and some sites give way too much information while others are simply misleading. So let me break it down.
Hair porosity is the term which describes your hairs’ ability to absorb and retain moisture. It is categorized by low (compact), normal or high (porous) porosity. Before we dive further into these categories let’s understand the basic structure of the hair shaft.
Basic Layers of the Hair Shaft:
The outermost layer of the hair shaft made of Keratin which is comprised of proteins. Under a microscope the cuticle looks like overlapping scales similar to roof shingles. The cuticle serves as protection to the inner layers.
The middle layer of the hair shaft containing pigment cells which gives the hair its’ natural color.
The innermost layer of the hair shaft. The purpose is not entirely understood and it can be absent in some hair strands.
The cuticle scales are typically covered with sebum (the body’s natural oil for coating the scalp and hair shaft) which allows them to lay flat and give the hair shaft a smooth feel and appearance. The sebum attracts dirt and matter from the air. During the cleansing process the scales of the cuticle are lifted and water enters the cortex to properly clean the hair. The scales are lifted long enough for conditioning. After the conditioning process, it is important to seal the moisture in with oil such as coconut or jojoba which helps to lay the scales flat.
With all that being said, let’s explore hair porosity.
Defined by a characteristic in which the cuticle scales are too closely layered making the absorption of moisture difficult or slow.
Signs of low porosity:
- Hair seems to take a long time to get wet
- Hair dries quickly
- Hair seems to be extremely dry even after deep conditioning
- Hair looks dull and feels tough
Defined by your hairs’ ability to absorb and retain adequate moisture while keeping out excess moisture from the air. Healthy hair can absorb up to 30% of moisture. Hair typically feels moisturized after conditioning and can look soft.
Defined by a characteristic in which the scales of the hair cuticle are continually lifted too high which causes too much moisture to enter the cortex (usually caused by chemical damage) and while the hair dries too much moisture is being released. Hair can absorb up to 45% of moisture. Too much moisture absorption can pose an issue because it causes the cortex to swell too far making the hair more susceptible to breakage.
Signs of high porosity:
- Hair seems to take a really long time to dry
- Hair is brittle and breaks easily
- Once the hair is dry, it feels too dry
- Hair is always frizzy
Understanding how moisture enters and leaves your hair is essential to natural hair care.