Thumb Sucking: What You Need to Know

Thumb sucking is a natural habit for babies and children to help them self-soothe and feel more secure. All babies are born with the reflex to suck because it is needed to eat and drink. Beyond nutrition, sucking provides a calming effect for babies and young children. 

Most children stop sucking their thumb on their own between the ages of 2 and 4. Thumb sucking usually does not cause permanent problems unless children continue to do it past age 5.

This article will describe the long-term effects of thumb sucking and provide suggestions for how to break the habit.

Portrait of a young girl holding a blanket and leaning against the bed in a bedroom

Thomas Barwick

Why Do Children Suck Their Thumb?

Thumb sucking is a form of non-nutritive sucking, which refers to any sucking action that is not used to eat and drink. Babies and young children usually suck their thumbs as a way to soothe themselves and feel calmer. Non-nutritive sucking has even been found to provide pain relief during medical procedures. This usually involves a pacifier. 

How Long Does Thumb Sucking Last?

Thumb sucking is a common habit that usually lasts until children are between 2 and 4 years old. Each child is different, so consider talking with your healthcare provider or pediatrician if you are concerned about your child’s habits. 

When to Stop Thumb Sucking

While thumb sucking is a common habit for babies and toddlers, it may lead to problems if continued for too long. Thumb sucking changes a child’s teeth and mouth over time. For this reason, it is recommended that children stop sucking their thumb by the time their adult teeth are coming in, usually around age 5 or 6.

Long Term Effects of Thumb Sucking

When a child continues thumb sucking into their school-age years, long-term problems can occur. Thumb sucking (or using a pacifier) changes the way that a child’s teeth grow. The pressure from the thumb pushes the teeth to stick out. This affects a child’s entire mouth because the teeth no longer meet properly when the child bites down. This is known as a crossbite

When the upper and lower teeth stick out as they grow, other problems like broken teeth can occur. Children who suck their thumbs after toddlerhood are more likely to need orthodontic treatments such as braces, expanders, and other tools to correct the shape of the teeth. 

How to Stop the Thumb Sucking Habit

Most parents are anxious to help their children stop sucking their thumbs in order to prevent future dental problems. This is understandable, but it is important to remember that pushing too hard may cause your child to cling to thumb sucking more. Most children will stop thumb sucking on their own without adult intervention. 

To encourage your child to begin to give up the habit of thumb sucking, try incorporating one or more of these techniques:

  • Replace the habit: Most children suck their thumb without consciously thinking about it. Help your child stop by coming up with a replacement habit to keep their hands busy. This could include making a fist or holding a favorite small toy.  
  • Offer rewards: Set goals with your child and offer rewards when they are able to avoid thumb-sucking for a set period of time. Praise your child for trying and consider incorporating sticker charts, small treats, or fun surprises to help the process along. 
  • Provide reminders: When you notice your child sucking their thumb, gently redirect them. Always avoid harsh words or punishments. 

If your child continues to suck their thumb despite your attempts to help them stop, talk with your healthcare provider, pediatrician, or dentist. There are dental tools that can be placed in your child’s mouth to prevent them from thumb sucking. They may also discuss placing a bitter substance on your child’s thumb to discourage the habit. Talk with your healthcare provider before trying one of these methods. 

A Tip to Discourage Thumb Sucking

Remember to always use kind words and a gentle demeanor when discouraging thumb sucking. If you notice your child start sucking their thumb, momentarily pause what you are doing. This could mean pausing their show or stopping a bedtime story. Gently remind them to stop sucking their thumb and praise them for trying. Then resume your activity together. 

Try not to worry if your child has a difficult time breaking the thumb-sucking habit. Too much pressure to stop thumb sucking may delay the process.

Summary

Thumb sucking is a natural habit for babies and young children. It allows them to soothe themselves and feel more relaxed. Most children stop sucking their thumbs between the ages of 2 and 4. If your child is still regularly sucking their thumb when they are 5 or 6 years old, it could affect their oral health and teeth alignment. 

A Word From Verywell 

Encouraging your child to stop sucking their thumb is a daunting process for everyone. It may be helpful to remember that most children stop on their own and do not require any special interventions. Talk with your healthcare provider about tips for discouraging thumb sucking or if you are concerned about your child’s teeth. 

Frequently Asked Questions

  • How do you fix a thumb-sucking overbite?

    Overbites caused by thumb sucking are usually treated with braces. Talk with your child’s dentist about being referred to a pediatric orthodontist for a consultation. 

  • Can thumb-sucking damage be reversed?

    Most effects of thumb sucking can be reversed. When children continue to suck their thumb past age 5 or 6, more serious changes in their teeth can occur. This is because that is the age when their adult teeth start to come in. 

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Academy of Pediatrics. Pacifiers and thumb sucking.

  2. Children’s Hospital of Philadelphia. Thumb sucking.

  3. Ling HT, Sum FH, Zhang L, Yeung CP, Li KY, Wong HM, Yang Y. The association between nutritive, non-nutritive sucking habits and primary dental occlusion. BMC Oral Health. 2018;18(1):145. doi:10.1186/s12903-018-0610-7

  4. American Psychological Association. Thumb sucking.

  5. Borrie FR, Bearn DR, Innes NP, Iheozor-Ejiofor Z. Interventions for the cessation of non-nutritive sucking habits in children. Cochrane Database Syst Rev. 2015;2015(3):CD008694. doi:10.1002/14651858.CD008694.pub2

By Carrie Madormo, RN, MPH
Carrie Madormo, RN, MPH, is a health writer with over a decade of experience working as a registered nurse. She has practiced in a variety of settings including pediatrics, oncology, chronic pain, and public health.