If hair is dry and brittle, what type of porosity does it typically indicate?

When hair is described as dry and brittle, it typically indicates high porosity. High porosity occurs when the hair cuticle is lifted or damaged, allowing moisture to enter the hair shaft more easily, but also causing moisture to escape just as quickly. This results in hair that can easily absorb water but fails to retain it, leading to conditions of dryness and brittleness.

In contrast, low porosity hair features tightly bound cuticles that resist moisture absorption, making it less likely to feel dry and brittle unless other issues are present. Medium porosity hair has a balance that allows for adequate moisture retention without extreme dry or brittle conditions. Variable porosity refers to hair that has different porosity levels along its length, often due to different treatments or damage over time, which can cause inconsistencies in texture but does not specifically indicate a consistent dry and brittle feel.

Thus, the characteristics of dry and brittle hair point towards high porosity being the correct identification of the underlying issue.