What is the typical pH range for most shampoos?

The typical pH range for most shampoos falls between 4.5 and 6.5, making this answer correct. This range is important because it closely aligns with the natural pH of the scalp and hair, which is slightly acidic. Formulating shampoos within this range helps to maintain the integrity of the hair and scalp, preventing damage and ensuring that the cuticles remain closed.

When shampoos have a pH that is too high or too low, it can lead to undesirable effects such as dryness, irritation, or an imbalance in the scalp's natural oils. For instance, formulations that are too alkaline (higher than 7.0) may strip the hair of essential moisture and lead to frizz or breakage. Shampoo with a pH outside the typical range may not effectively cleanse the hair while maintaining its health and shine.

Shampoos falling outside the correct pH range can impact not only the hair's appearance but also the scalp’s health, potentially leading to issues like dandruff or sensitivity. Therefore, understanding and selecting shampoos with the appropriate pH is crucial for optimal hair care.