Redseal Hairstyling License Practice Test

The natural pH of hair typically falls within which range?

1. 3.5 - 4.5

2. 4.5 - 5.5

3. 5.5 - 6.5

4. 6.5 - 7.5

The correct answer is: 4.5 - 5.5

The natural pH of hair typically falls within the range of 4.5 to 5.5. This slightly acidic pH is important for maintaining the health and integrity of the hair. The acidity helps to keep the cuticle layer tightly closed, which reduces frizz, enhances shine, and prevents environmental damage. Additionally, products that fall within this pH range are generally gentler on the hair and scalp, providing optimal conditions for the hair's natural oils to keep it moisturized and healthy. When hair is exposed to products or treatments that are significantly outside this pH range—either too acidic or too alkaline—it can lead to issues like cuticle lifting, which may cause damage, dryness, and breakage. Understanding the natural pH of hair is essential for hairstylists to select appropriate products and techniques that promote hair health.