What does the term "porosity" in hair refer to?

The term "porosity" in hair refers specifically to hair's ability to absorb moisture. This property is crucial in determining how well the hair can take in and retain moisture and products. High porosity hair tends to absorb moisture quickly but also loses it just as fast, which can lead to dryness. On the other hand, low porosity hair has a tightly packed cuticle layer that makes it more resistant to absorbing moisture. Understanding porosity is essential for selecting the right hair care products and treatments to maintain healthy hair, as it affects hydration, styling, and overall hair health.

Other terms, such as thickness, color, or growth rate, do not relate to porosity. Thickness refers to the diameter of the individual hair strands, color pertains to the pigment present in the hair, and growth rate indicates how fast hair grows over time. While these characteristics are important in hair care, they do not define the hair's porosity and its moisture absorption capabilities.