Thumb Sucking Health Article

Thumb Sucking

A harmless childhood habit of sucking the thumb for comfort.

About half of all children suck their thumbs during infancy, with most starting in the first months of life. Ultrasound pictures of intrauterine life have even shown fetuses sucking their thumbs. Infants explore their world by putting objects in their mouths and sucking on them. Thumb sucking appears to be a natural habit of children in all parts of the world. Sucking the thumb is soothing for a small child, and many children continue this habit for comfort and security into the early school years. Thumb sucking is most prevalent in children under two, and most children give up the habit on their own by age four.

Thumb sucking by itself is not a cause or symptom of physical or psychological problems. It is not known why some children suck their thumbs longer than others. More girls than boys suck their thumbs beyond age two. Researchers speculate that boys receive stronger negative messages from parents and peers that thumb sucking is infantile and not acceptable. Thumb sucking offers security to a child, but this behavior does not imply that the child is insecure. Most children have some sort of selfcomforting ritual that may involve sucking the thumb, fingers, or a pacifier; pulling or twisting their hair; or stroking or sucking a soft toy or blanket. These are all normal habits of infancy that are eventually outgrown.

Some 19-century physicians feared a variety of consequences from thumb sucking, such as weak moral character, and earlier generations of parents were advised to break this habit forcibly. Parents were sometimes asked to place mechanical constraints on their children's hands to keep their thumbs out of their mouths. Children's thumbs were sometimes coated with a bitter substance, taped, or covered with gloves. It was also considered necessary to shame and humiliate the thumb sucker. Modern doctors find few negative health effects of thumb sucking, even if prolonged, and parents are urged to let their children outgrow the habit on their own. Thumb sucking may be more of a problem for the parent than the child, if the parent is unsettled by the behavior. But weaning a young child from the habit before he or she is ready is usually difficult, and may only prolong the thumb sucking.

There are a few cases where thumb sucking may become a problem. If a school-age child sucks his or her thumb and is teased by classmates, the child may wish to quit, and need help, either from the parents or a counselor. Some dentists warn of misalignment of permanent teeth of a child of five or six sucks the thumb with a lot of pressure on the teeth. Not all dentists agree, however, that thumb sucking is harmful to teeth development. But if a child's dentist sees evidence that thumb sucking is causing a particular problem, the child may need to be urged to quit. If the child is having trouble quitting the habit, parents may be able to help with positive reinforcement. The child can be given a sticker or small reward for a day spent without thumb sucking. Parents can also help the child find something else to do with her hands when she has the urge to suck her thumb. Parents should avoid negative pressure on children to stop sucking their thumbs; this habit is eventually outgrown by all children. In extreme cases, some dentists can prescribe an oral device to alter the shape of the roof of the child's mouth, so that it is unpleasant for the child to continue sucking. An aluminum thumb brace has also been invented to deter children from sucking their thumbs.

Books

Azrin, Nathan. Habit Control in a Day. New York: Simon and Schuster, 1977.

Eisenberg, Arlene. What to Expect the First Year. New York: Workman Publishing, 1988.

Leach, Penelope. Your Baby and Child from Birth to Age Five. New York: Knopf, 1989.

Spock, Benjamin. Dr. Spock's Baby and Child Care. New York: Dutton, 1992.

Periodicals

Eberlein, Tamara. "Nervous Habits." Redbook 182, April 1994, pp. 178+.

Thompson, Andrea. "Those Nervous Habits." Good Housekeeping 221, September 1994, pp. 165+.