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

Porosity refers to the hair's ability to absorb moisture and product. It describes how well the hair can take in water, oils, and conditioning treatments. Hair porosity is an important factor in maintaining healthy hair, as it influences how products work on the hair and how effectively moisture is retained. High porosity hair, for instance, absorbs moisture quickly but may also lose it just as easily, often resulting from damage or over-processing. In contrast, low porosity hair resists moisture absorption and may benefit from the application of heat or specific products to enhance penetration.

Understanding porosity helps cosmetologists select appropriate hair care products and treatments tailored to individual hair needs, making it a crucial concept in hair health and maintenance.