Hand biting is a normal behavior in infancy, but children who still eat their hands after the age of 1 may have iron or zinc deficiencies. If the child is a picky eater or has digestive problems, it will lead to a lack of iron or zinc and other nutrients, which in the long run may lead to xerophagia, hand-eating, hair-eating and other symptoms, which has a greater impact on the growth and development of the child. Parents should take their children to the hospital for examination to identify the cause of the problem, and then choose the appropriate medication under the guidance of the doctor, and supplement with iron and zinc if necessary. The symptoms of hand eating in children are not normal, they should go to the hospital in time to do the appropriate examination, to clarify the specific causes of the disease.