Thumb Sucking 101

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Thumb sucking can be one of the cutest things that infants and toddlers do. As your toddler enters early childhood though, it’s a good idea to start thinking about ending this habit. While thumb sucking has its benefits for infants, it has a number of harmful effects for older children. Luckily, this is a challenge that a lot of kids face at some time or another. So, there are plenty of good ways to help them overcome it.

Why Do Kids Suck Their Thumbs?

Babies have natural rooting and sucking reflexes. These instincts are hard wired so that newborns seek our nourishment shortly after they’re born. However, beyond just looking to sucking for nourishment, it’s pretty common for infants to suck their thumbs as well. A lot of babies actually do a fair amount of thumb sucking when they are in the womb, and then continue in the outside world.

One of the big benefits of thumb sucking is that it helps infants to soothe and entertain themselves. It’s not uncommon to observe this behavior whenever they are bored, tired or upset. In fact, babies that suck their thumbs are often better at putting themselves to sleep at an early age.

More than 75% of infants suck their thumb through the first year of life. Over time, some drop this habit on their own, and others continue on.

When Should Kids Try To Stop?

A lot of kids stop sucking their thumbs on their own when they are 6 – 7 months old. Most stop between ages 2 and 4. However, about one in five children continue to suck their thumbs after turning 5.

For children under 5 years of age, thumb sucking really isn’t a big deal. However, once they turn 5, it’s a good idea to try and help them to stop. This is true both for social reasons, and also because their permanent teeth will likely start erupting fairly soon. If your child is a particularly vigorous thumb sucker, it can be a good idea to try stopping a little earlier since it is more likely to have harmful effects.

How Is Thumb Sucking Harmful?

As kids get older, there are a lot of developmental and social issues associated with thumb sucking.

Dental Issues

Thumb sucking can cause a whole range of dental issues. Perhaps the most serious is that kids can develop an open bite. With an open bite, both the top and bottom front teeth become directed outward and do not touch.

dental office

Similarly, overbites are fairly common for thumb suckers. In this case, it’s just the top teeth that face outward. Prolonged thumb sucking can even change the shape of the roof of a child’s mouth.

One thing to note is that the likelihood of a child developing any of these issues is impacted by how frequently and how intensely they suck. If a child simply rests their thumb in their mouth on occasion, it is less likely to have as big of an impact on how their teeth develop. On the other hand, if a child sucks vigorously every day, serious dental problems are almost sure to arise.

Since orthodontic work can be quite expensive, this is a powerful motivator for parents to help their little ones to stop.

Speech Impediment

Kids that suck their thumbs often develop speech impediments. This is in part a secondary effect related to the dental issues that arise. In particular, “D”, “T”, and “S” sounds can present challenges for thumb suckers. Some children develop lisps as well.

Social Issues

While thumb sucking is quite common among infants and toddlers, it is less common by the time kids reach kindergarten. Kids that are still sucking at this age are often the subject of teasing and ridicule from their peers.

Often times, thumb sucking is a subconscious behavior. So, kids might not even realize that they are doing it in public. Some children are able to control things a bit better, and only suck in private or at bed time.

Other Health Issues

While dental issues get the lion’s share of attention, there are some other health issues that crop up as well. First off, thumb sucking does a lot to spread germs. In addition, the skin on the thumb may become cracked or bleed, making it more vulnerable to infection.

How Can You Help Your Child To Stop Sucking Their Thumb?

Like a lot of habits, thumb sucking can be a difficult one to give up. In fact, it may take up to six weeks to break this habit. But, there are a lot of things that you have at your disposal to help your child overcome this daunting challenge:

  • Identify challenging times. Some kids go throughout most of the day without sucking, but do so whenever a certain trigger arises. For example, a lot of kids suck their thumbs when riding in the car, watching TV, or going to sleep. If you can identify these triggers, you can try to preempt them. For instance, you might give your little one a toy to play with whenever the TV is turned on, or whenever they get into the car.
  • Set attainable goals. It can be really hard to give up cold turkey. So, be sure to set realistic goals. Instead of trying to go a whole day without sucking at the beginning, maybe your child starts by trying not to suck for an hour before bed each day. Over time, you can make the goals harder and harder until your little one has broken the habit entirely.
  • Have a talk. Having a conversation about quitting is an important step. Things will go much more smoothly if they understand why they should quit, and actually want to do so. It’s also a good idea to let them have some input into the strategy for quitting. You want to set this up as something you are both trying to overcome, rather than something that you are forcing upon them.
  • Wear mittens or gloves. Thumb sucking is often a subconscious behavior. So, kids don’t even realize when they’re doing it at times. By putting something on their hands, like a glove, mitten, or thumb cover, you can eliminate this subconscious behavior. In this case, the child would actually have to take make the conscious decision to take the glove or mitten off their hand before sucking. Kids don’t have to wear gloves all day. But, this can be useful at bed time and other challenging times.
  • Something bitter. Putting something bitter on the thumb nail is another way to help them quit. Not only will this be a good reminder whenever they start to suck, it might also create a negative association with sucking over time. Some parents use nail polish, but be sure to make sure that whatever you use is safe to ingest. 
  • Sticker chart. It’s fun putting on a sticker after each success. This is also a great way to show your child how much progress they are making over time. Just be sure to keep the goals attainable. So, perhaps in the beginning, your little one earns a sticker by not sucking at certain times of day. Then, over time, maybe it takes a full day to earn a sticker.
  • Rewards. There is no shortage of rewards that you can offer to help motivate your little one. You might read an extra book at night if they make it through a whole day. Then, if they go for a week, you might do something extra special, like go out for ice cream.
  • Heap on the praise. This is a challenging habit to break. So, make sure you heap on the praise and cheer them on. Be sure to avoid scolding them if they slip up. This can lead to a power struggle dynamic and actually make it take longer to quit.
  • Oral appliances. If your child is really struggling, you can talk to their dentist about palatal bars and cribs. These can be helpful, though I wouldn’t suggest this unless all else has failed.

Final Thoughts

While thumb sucking can sometimes be irritating for parents, it’s important to remember that it’s really not too harmful until your child’s permanent teeth start to come in. It’s also a fairy common behavior, and something that sooner or later your child will learn to give up. Like a lot of things in the world of parenting, patience is one of the keys when you’re helping your child with this hurdle.

Howard is a co-founder of Smart Parent Advice. When he isn't spending time with his wife, Kristin, or his two children, he can often be found running around on the tennis court.