Porosity pertains to the hair's ability to absorb and retain moisture. This also includes the rate at which water and/or topical products that are applied to the hair are absorbed into the strands. The more porous your hair is, the more moisture it can hold, making it healthier and easier to manage. During the course of a lifetime, porosity can change.
There are three levels of Hair Porosity so let's, discuss this in further detail.
1. HIGH POROSITY
If someone has high porosity, it means they have a hard time keeping their hair moisturized. And, even with regular attention, the texture and overall appearance of the hair can seem dry... controlling frizz is also harder. This is because the hair cuticle itself has signs of damage. The cuticle is the outermost layer of the strand. If you were to examine it very closely, you would see cracking, splitting and irregular texture. A person with high porosity hair can absorb moisture fast, but they can also lose moisture just as easily. In order for hair to retain moisture, the follicle needs to be "Closed", but in this situation the process is a struggle. As you age, hair naturally tends to develop a higher porosity level. Things that accelerate this process are long-term use of chemicals and exposing the hair to high levels of heat from blow dryers, flat irons, curling irons, etc.