How can variations in hair porosity affect perm results?

Variations in hair porosity significantly impact how well hair holds curls after a perm. Hair porosity refers to the hair's ability to absorb moisture and chemicals, which is influenced by the condition of the hair cuticle. Hair with high porosity can absorb chemicals more easily, which may lead to better curl retention. This is because the cuticle allows the perm solution to penetrate more deeply and effectively alter the hair’s structure. Conversely, hair with low porosity may struggle to absorb the perm solution fully, leading to less effective curl formation and retention.

Understanding this aspect is crucial for stylists when determining the technique and products to use for each client's hair type, ensuring optimal results in achieving the desired curl pattern. While factors such as color, temperature, and general chemical interactions are important, they are not as directly related to the curl retention as porosity is.