When heat production decreases and heat loss increases, it disrupts body temperature regulation. This prevents normal metabolic function, weakens immunity, and leads to illness.
2. Causes respiratory issues
Hot water during hair washing dilates scalp capillaries, significantly accelerating body heat loss.However, after washing, the hair remains in a state of moisture evaporation. During this heat dissipation process, the body may become chilled. This triggers reflexive contraction of the respiratory tract, reducing blood flow and lowering resistance in the upper respiratory system.
Latent bacteria may then invade the body, causing respiratory difficulties and symptoms like colds, coughs, and runny noses, thereby impacting health.
3. Hair Loss
Washing hair at night also accelerates heat loss from the head, disrupting normal blood and qi circulation. This impairs proper nourishment to the scalp, making hair more prone to shedding.
Damp hair is highly sensitive. As it gradually dries, it becomes brittle and susceptible to breakage and loss.
4. Insomnia
Going to bed with wet hair can also cause insomnia. This is because damp hair traps moisture around the head, potentially leading to blood stasis over time and obstructed meridians.
If nighttime temperatures drop significantly, dampness can enter the head, allowing cold pathogens to invade. This disrupts brain function, affecting normal sleep patterns and leading to insomnia.