South Carolina Cosmetology Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

Glycerin is commonly included in hair products because it is a powerful humectant, which means it attracts moisture from the environment and helps retain it within the hair. This property makes glycerin particularly effective for maintaining hydration in hair, especially for those with dry or damaged strands. By pulling in moisture, glycerin can enhance the overall moisture balance of the hair, promoting softness, shine, and manageability.

In contrast, other ingredients listed may affect hair care differently. For example, alcohol can often lead to dryness, as it can strip moisture from the hair. Sulfates are primarily used for cleansing and can also contribute to dryness, making hair feel brittle. Silicone, while effective at providing a protective coating to the hair strands and imparting shine, does not inherently retain moisture like glycerin does. Thus, glycerin stands out as the ideal ingredient for promoting moisture retention in hair products.