Your Child's Habits

Thumb Sucking

The popularity of the thumb as the preferred digit to suck might suggest that it's more flavorful than, say, the index finger. But the preference for thumbs appears to be an accidental choice, resulting from the thumb coming into contact with the mouth during random movements made by an infant.

Some kids also suck their fingers, hands, or their entire fists in addition to, or instead of, their thumbs. Most thumb suckers are younger kids. In fact, anywhere from a quarter to half of 2- to 4-year-olds suck their thumbs.

Many kids suck their thumbs to calm and comfort themselves. But frequent or intense thumb sucking beyond 4 to 5 years of age can cause problems, including dental problems (such as overbite), thumb or finger infections, and being teased.

What Causes a Habit?

Why do your son's fingers appear to be an extension of his mouth, and why is there always a propeller of hair circling above your daughter's head? Experts admit that they're not always sure what causes a habit, but that it is a learned behavior that usually provides a positive outcome for the child.

Habits may develop as entertainment for a bored child or, more commonly, as a coping mechanism to soothe an anxious one. The next time you see nail biting or hair twirling, try to recall if your child has recently had a stressful experience. If so, the behavior might be your child's attempt to relieve tension just as you would by working out at the gym.

On the other hand, some kids engage in habits when they're relaxed, such as before falling to sleep or quietly listening to music. Other habits may be leftovers from infancy. In infants, thumb sucking is a common self-comfort behavior that has pleasurable associations with feedings and the end of hunger. So it may linger into childhood because of its positive associations.

Or perhaps the explanation for your child's nail biting is in your mirror. Do you bite your nails? Studies suggest that nail biting may have a strong familial or genetic component.

Still, other kids will engage in habits to attract attention or as an attempt to manipulate their parents. If kids feel that their parents are ignoring them, they may engage in the annoying habit because they know that it will provoke a reaction from Mom or Dad.

Coping With Your Child's Habit

The good news is that most habits disappear, usually by the time a child reaches school age, because the child no longer needs it or outgrows it.

But if you think it's time to help your child break a habit, consider these steps:

• Calmly point out what you don't like about the behavior and why. This approach can be used with kids as young as 3 or 4 to help increase awareness of the problem. Say something like, "I don't like it when you bite your nails. It doesn't look nice. Could you try to stop doing that?" Most important, the next time you see the nail biting, don't scold or lecture. Punishment, ridicule, or criticism could cause the behavior to increase.
• Involve your child in the process of breaking the habit. If your 5-year-old comes home crying from kindergarten because the other kids made fun of his thumb sucking, understand that this is a way of asking you for help. Parents can ask their kids what they think they could do to stop the habit or if they want to stop the habit. Come up with some ways to work on breaking the unwanted habit together.
• Suggest alternative behaviors. For example, when if your child is a nail-biter, instead of saying, "Don't bite your nails," try saying, "Let's wiggle our fingers." This will increase awareness of the habit and may serve as a reminder. To occupy your child's attention, try providing a distraction, like helping you in the kitchen or working on a craft.
• Reward and praise self-control. For example, allow your little girl to use nail polish if she lets her nails grow. Or every time your son refrains from sucking his thumb, reinforce the positive behavior by praising him and giving him a sticker or other small prize.
• Be consistent in rewarding good behavior. If you fail to notice good behavior, it will disappear over time. The new, positive habit must be firmly established before the old one will disappear.

For the best success, it's important that your child is also motivated to break the habit. And because habits take time to develop, they're also going to take time to be replaced by alternative behavior, so be patient.

When Is a Habit No Longer Just a Habit?

In some instances, a habit may be the result or the cause of a physical or psychological problem. For example, a nose-picker may be uncomfortable because there's actually an object stuck in the nose. And the habits themselves may cause some medical complications, such as:

• nosebleeds in the nose picker
• ingrown or infected nails in the nail biter
• dental problems, such as malocclusion (the failure of the teeth in the upper and lower jaws to meet properly) or thumb or finger infections in the thumb sucker

A habit may no longer be a simple habit if it negatively affects a child's social relationships or interferes with daily functioning.

Older kids who constantly suck their thumb might be experiencing significant stress or anxiety. If kids are the subject of teasing at school or have difficulty talking because they won't take their thumbs out of their mouths, the behavior has progressed beyond a simple habit. Kids who pull their hair out may have trichotillomania, a condition that results in hair loss. And habits that are in response to obsessive thoughts may be a sign of OCD.

However, most habits don't cause any significant problems and tend to improve as kids get older. But if you're concerned about your child's habits, talk with your doctor.

Reviewed by: Steven Dowshen, MD
Date reviewed: August 2011