Normal lip color is mostly pink, if the color of red is too bright or deep purplish red, that is, the lips of the mouth are flushed. Under pathological conditions, such as the occurrence of oral mucosa inflammation, or bacterial infectious diseases, cardiovascular diseases, digestive system diseases, etc. Preventive measures: (1) When working in the field, do a good job of personal protection. Such as wearing a wide brimmed hat to prevent the occurrence of lip mucosal lesions. (2) When the mouth and lips are cracked, you should pay attention to keep warm or apply lip protection grease (cream), and never lick the wet lips with your tongue to prevent aggravating the degree of lip cracking. Because the saliva on the tongue contains various enzymes and many kinds of bacteria. (3) For various reasons caused by the mucous membrane scabs of the mouth and lips should be properly handled. Some people are accustomed to tearing scabs and have a history of tearing lip scabs several times, which can easily cause bleeding secondary to infection. The proper treatment is to go to a hospital dentistry department. (4) Quit smoking and drinking, and actively deal with the white and red spots of the mucous membrane of the mouth and lips. (5) Pay attention to adjust the diet structure, pay attention to eat more fresh vegetables and supplement various vitamins. (6) Should not simply eat light food, should be a combination of meat and vegetables, food diversification, drink more water, maintain the nutritional balance in the body. (7) Patients with fever must pay attention to oral hygiene, to develop the good habit of rinsing after eating, brushing before going to bed, especially after brushing teeth no longer eat. It is best to rinse the mouth with light salt water 1 to 3 times a day.