Hair that has received a color service previously will:

Hair that has received a color service previously typically exhibits greater porosity. This is because the coloring process often opens up the hair cuticle, allowing for the dye to penetrate the hair shaft. As a result of this opening, the hair can absorb moisture and products more easily, leading to a higher level of porosity. Increased porosity means that the hair may also be more susceptible to damage and may require special care to maintain its health and appearance.

The characteristic of having less shine can often be associated with porosity, but it does not directly explain the effects of previous color treatments on the hair's structural integrity. Resilience is not commonly increased with prior color service, as chemical processes can lead to weakening of the hair. Lastly, hair that has been colored is unlikely to remain completely unchanged; rather, it will have undergone alterations that affect its texture, porosity, and overall condition.