New Jersey Cosmetology and Hairstyling Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

Clients should be advised against using hot water for hair washing primarily because it can strip natural oils from the hair. When exposed to high temperatures, the scalp and hair can lose their protective oils, which are vital for maintaining moisture and preventing dryness. These natural oils are essential for healthy hair, as they help to keep the hair cuticle smooth, reduce frizz, and enhance shine.

Without these oils, hair may become brittle, susceptible to breakage, and may appear dull and lifeless. Additionally, the loss of these oils can lead to an imbalance in the scalp's natural ecosystem, potentially resulting in dryness or even oiliness as the scalp compensates.

While other concerns like hair damage and scalp irritation can occur with hot water, the immediate and significant effect of hot water on stripping the hair of its natural oils is a key reason to recommend cooler temperatures for washing. This helps in retaining hydration, promoting healthier hair overall.