The red area around the lips of the human body is called the “red edge of the lips”, and its wetness is maintained by the rich local capillaries and a small number of underdeveloped sebaceous glands. Children’s dry and cracked lips is what we usually call lip inflammation, its causes are very complex, there may be the following reasons: 1, due to the low humidity and sandy wind in autumn, the human skin mucous membrane blood circulation is poor, if the fresh vegetables eat less, the human body vitamin B2, vitamin A intake is not enough, there will be dry and cracked lips. 2.It may be caused by endocrine disorder. 3.It may be caused by the lack of calcium and zinc trace elements. 4.It may be caused by eating certain fruit juices, external toothpaste foam stimulation and allergy. 5, some children like to lick with their tongues in order to moisten their lips, in fact, this is a bad habit, because licking the lips can only bring a short period of wetness, when the water evaporates from the lips will take away more water inside the lips, so that your lips fall into the vicious cycle of “dry – lick – more dry -The result is that the more you lick, the more painful it is, and the more you lick, the more cracked it is. Besides, saliva contains amylase and other substances, the wind blows, the water evaporates, taking away the heat, making the lip temperature lower, amylase will stick to the lip, causing the contraction of deep connective tissue, lip mucosa wrinkled, and thus dry and cracked more. There is no need to panic when your child has dry and cracked lips, first of all, you should change your bad lip licking habits. Secondly, you should also drink more water, eat more fruits and vegetables to replenish vitamins, and take more calcium and zinc, and it will soon heal.