What is the normal pH of the hair?

The normal pH of hair is typically in the range of 4.5 to 5.5, which is slightly acidic. This acidity helps to maintain the hair's cuticle integrity and protects it from damage. An acidic environment can also discourage the growth of bacteria and fungi, which can negatively affect both the hair and scalp.

Maintaining this pH balance is crucial because products used in hairstyling or treatment, such as shampoos and conditioners, are formulated to be within this range to avoid causing harm to the hair. If the pH were to become too alkaline (above 7), it could lead to an opening of the hair cuticle, leaving the hair vulnerable to damage, dryness, and breakage. Additionally, if the hair is too acidic (below 4.5), it could become overly stressed, resulting in brittleness and dullness.

Understanding the normal pH range of hair is fundamental when selecting hair care products and treatments, enabling better care and maintenance for healthy hair.