When should women not wash their hair?

It is not easy to go to bed after washing your hair at night

Of course, it would be best if you could give your hair enough time to dry thoroughly after washing it at night before going to bed. But sometimes I am too busy and wash my hair after 10 o'clock in the evening. After washing my hair, I am so tired that my eyelids are so heavy that I can't open them, so I fall asleep before my hair is dry.

If you do this, the older generation will say that you will have a headache in the future. In fact, through modern scientific research, people have found that this is not without reason.

We must know that during the metabolism process, the human body always generates heat to maintain body temperature. This heat is also transmitted to the body surface through the blood circulation, and continuously dissipated to the outside world through radiation, conduction, convection and evaporation.

People with strong physical resistance have normal body temperature regulation function. Through regulation, the two processes of heat production and heat dissipation are balanced. That is, when the body temperature tends to drop, heat production increases and heat dissipation decreases, so that the body temperature remains at around 37°C.

Sleeping with wet hair can easily lead to colds

However, for people with weak physical resistance, their ability to automatically regulate body temperature and maintain normal body temperature is poor, so they are prone to catching a cold when the whole body or a certain part of it is exposed to cold.

When we wash our hair with hot water, the warm effect causes the capillaries in the scalp to expand, and the amount of heat radiated to the surrounding area by the body increases. At the same time, because the hair is wet after washing, a large amount of water evaporates, taking away a lot of heat. Generally, when one gram of water evaporates, 500 calories are taken away.

Due to the increased heat dissipation, the body is frozen, and the upper respiratory tract capillaries contract reflexively, the local blood flow decreases, and the upper respiratory tract resistance decreases, allowing the viruses or bacteria that have already existed in the local area to take advantage of the opportunity to enter, grow and multiply, causing an upper respiratory tract infection, and thus cold symptoms such as runny nose, nasal congestion, headache and even fever.

If you fall asleep with your hair wet, the regulatory function of your body's temperature regulation center will be low, making it more likely to catch a cold.

Therefore, generally speaking, it is best not to wash your hair before going to bed. If you want to wash it, dry it with a dry towel, and then use a hair dryer to blow dry your hair before going to bed. This way, you will not catch a cold. If you fall asleep with your hair wet, you are more likely to catch a cold.