Missouri Cosmetology Exam Practice 2026 – Complete Study Guide

The role of pH in haircare products is critical because it affects hair structure and health. Hair has a natural pH level that generally ranges from 4.5 to 5.5, which is slightly acidic. When haircare products are formulated with a pH that aligns closely with this range, they help maintain the hair cuticle's integrity. This curtails swelling and damage to the strands, promoting smoother hair and enhancing shine.

If the pH level of a product is too high or too low, it can lead to issues such as dryness, brittleness, and may exacerbate conditions like frizz or split ends. Therefore, using products with the appropriate pH helps in keeping the hair healthy and manageable.

While fragrance, hair dye color, and concerns exclusive to skin care products are important factors in the overall formulation and effectiveness of haircare items, they do not directly relate to the mechanical and chemical interactions that the pH level has on hair's structure and health.