What effect does a high pH level have on hair?

A high pH level affects hair primarily by causing the cuticle, which is the outer layer of the hair, to swell. When the cuticle swells, it can open up, making the hair more porous and susceptible to damage. This is important because the cuticle acts as a protective barrier, and when it is compromised, the inner structure of the hair can be exposed to environmental stressors and may lose moisture. This can lead to frizz, breakage, and an overall unhealthy appearance.

In contrast to the other options, which suggest positive effects on hair, a high pH level is generally detrimental. It does not increase shine and smoothness, nor does it condition the hair effectively or enhance color retention. In fact, the connection between pH, cuticle health, and hair structure is essential knowledge for anyone in the cosmetology field, as it informs the choice of products and treatments designed to keep hair healthy and vibrant.