New Mexico Cosmetology Practice Exam 2026 – All-in-One Guide to Mastering Your Certification!

Protein is commonly added to strengthen hair during hair treatments because hair is primarily made up of a protein called keratin. When hair is damaged due to factors like heat, chemicals, or environmental stressors, its protein structure can become weakened. Protein treatments help to repair this damage by reinforcing the hair shaft, filling in gaps in the cuticle, and improving the overall integrity and resilience of the hair. This is particularly beneficial for those with fine, brittle, or chemically-treated hair, as it can lead to improved texture, increased elasticity, and reduced breakage.

Other ingredients listed, such as moisturizers, conditioners, and colorants, serve different functions. Moisturizers primarily focus on hydration to improve the moisture balance of hair, while conditioners work to smooth and detangle hair and enhance its softness and manageability. Colorants, on the other hand, are used for altering the color of the hair and do not play a direct role in strengthening it. Therefore, protein stands out as the key ingredient specifically aimed at reinforcing and revitalizing the hair structure.