Ohio Cosmetology License Practice Exam

What is the ideal pH level for hair products?

1. 3.5 to 4.5

2. 5.0 to 6.0

3. 7.0 to 8.0

4. 8.5 to 9.0

The correct answer is: 3.5 to 4.5

The ideal pH level for hair products is between 3.5 to 4.5 because this range closely mirrors the natural pH of healthy hair and scalp. Hair has a natural acidic pH that helps maintain the integrity of the cuticle layer, which protects the inner structure of the hair shaft. Products formulated within this pH range not only help to keep the hair cuticles smooth and closed, which contributes to shine and manageability, but they also minimize the risk of damage and irritation to the scalp. Using products outside of this optimal pH range, especially in the alkaline range (7.0 and above), can lead to raised cuticles, resulting in frizz, tangling, and a lack of shine. Hair health can be compromised, making it more susceptible to breakage and damage over time. Therefore, formulating hair products to align with the ideal pH of 3.5 to 4.5 is essential for promoting healthy hair.