If you are a healthy person, your body condition and individual physique allow it, and you can ensure that your hair is thoroughly blow-dried, there are generally no strict requirements for the time period of hair washing. But for people with low immunity or suffering from primary diseases, it is not recommended to wash hair in the morning or evening. First, wash your hair in the morning: 1, the body’s blood circulation in the morning has not yet reached normal levels, low head shampooing may cause dizziness; in addition, people with cardiovascular and cerebrovascular based diseases, shampooing in the morning is likely to induce stroke or acute myocardial infarction and other diseases; 2, because of a night’s rest, the body’s blood sugar is consumed, at this time shampooing may appear hypoglycemia, producing dizziness, dizziness; 3, the morning time is relatively not Plenty of time, there may be hair not washed clean, easily lead to pore blockage, damage to the hair. If you do not have time to blow dry completely after washing your hair, it is easy to adhere to the dust and bacteria in the air, causing scalp discomfort. After washing the hair, the hair is relatively fragile, if in a hurry to go out, the sun’s ultraviolet radiation, easy to lead to hair breakage, split ends; 4, the morning temperature is low, the hair is not blow-dried, or did not pay attention to warmth, easy to catch a cold. Second, wash your hair at night: 1, the night temperature is relatively low compared to the day, after washing the scalp pores in a diaphoretic state, if the hair is not dry, moisture stays in the hair and scalp, not only affect the quality of sleep, but also easy to lead to colds, headaches; 2, if sleepy, failure to comb the hair carefully, will cause some damage to the hair quality, resulting in dry hair, frizzy. Sleeping with hair undried is also easy to breed bacteria and fungi, causing scalp infections, itchy scalp, dandruff, hair loss and other performance. Compared to washing your hair in the morning or evening, it is more recommended to wash your hair at noon and in the afternoon. At this time, the temperature is higher and time is relatively ample to dry hair naturally, reducing scalp discomfort while avoiding getting cold. If you have to wash your hair in the morning or evening, you should pay attention to blow-drying thoroughly before going out or going to bed.