Frequent dry and cracked lips are a relatively common phenomenon, mostly occurring in the autumn and winter seasons, when attention needs to be paid to replenishing moisture and applying lip balm to help relieve. In addition, the lack of vitamins in the body or suffering from lip infections and other reasons will also lead to frequent dry lips. 1, lack of water: lips for mucous membrane, no sweat glands, and will not secrete oil protection, when the climate is dry or the body is dehydrated will appear dry lips. Some people feel dry mouth will habitually lick their lips, saliva just stay on the lip mucosa will have a moisturizing feeling, but dryness will aggravate the phenomenon of cracking, there will be the more dry the more you want to lick, the more lick the dry lips, a vicious circle; 2, vitamin deficiency: fresh vegetable intake less, the body lacks vitamins, especially B vitamins, appear dry and cracked lips. b vitamins can help prevent and eliminate oral inflammation of the lips, tongue and skin inside; 3, lip inflammation: chronic lip inflammation is the most common, frequent lip biting makes the fissure repeatedly bleed and infected, forming a vicious cycle that will manifest itself as repeated dryness and flaking of the lips, and the fissure gradually deepens and worsens. There are also some other factors that can lead to dry and cracked lips, such as improper use of cosmetics to stimulate the lip mucosa, or some people are allergic to ultraviolet rays and have dry and cracked lips due to sun exposure. There are other diseases in the body, such as diabetes metabolism is fast, the body tissue dehydration appears lips often dry and cracked phenomenon, this situation needs to be treated for the original disease.