We recently wrote a post about pacifiers and how they can sometimes affect your child’s speech development, but what about thumb sucking and speech? Even though there are similarities between these self-soothing actions, there are also some notable differences that are worth knowing, especially if you’re the parent of an avid thumb-sucker!

Thumb Sucking: Is it a good habit or a bad one?

Just like with pacifiers, there’s no evidence to say that thumb sucking is inherently bad for babies and toddlers. Thumb sucking has its pros, and a few cons, and there are some considerations you may want to keep in mind. But as with most things, it’s not black and white.

As always, we want you to always do what’s best for your child and your family. Keeping that in mind, here are some of the pros and cons of thumb sucking:

Thumb Sucking: Pros & Cons

Pro: It’s soothing

Thumb sucking is a calming behaviour. It can be great for helping babies and toddlers to soothe themselves when they’re scared, upset, missing you, or need help falling asleep.

Pro: It’s easy

Compared to a pacifier, thumb sucking is nice because it’s easier than keeping track of your child’s pacifier. And, your child can do it completely on their own, freeing you up to help with other things.

Pro: It may lead to less allergies

There’s research to suggest that children who are exposed to more microbial organisms at a young age go on to develop less allergies. A study by Lynch, Sears, and Hancox (2016) found that because thumb sucking is one way to expose children to more of these organisms, it actually makes them less likely to have certain allergies.

Con: It exposes children to germs

The flip side of thumb sucking exposing children to more of the good microbial organisms, is that it also exposes them to more of the less-desirable ones: the germs! More germ exposure means there may be a higher chance of your child getting sick.

Con: It affects tooth formation (after a while)

Thumb sucking in itself isn’t anything to worry about, but prolonged thumb sucking (beyond age 4 or 5) can be. Because long-term thumb sucking can affect tooth formation, it can lead to problems like speech delays.

Tooth Formation & Speech Development

Tooth formation is important in terms of speech development because some speech sounds require the tongue tip to come into contact with the front teeth. If these teeth are misaligned, it will be harder for others to understand what they are saying.

Try this: Notice all of the different movements that happen when you speak. Notice how your teeth play a part in this, like when the tip of your tongue taps the back of your teeth, and when your tongue is between your teeth. You’ll have a better understanding of how our teeth play a role in saying speech sounds.

Prolonged thumb sucking can lead to malocclusion (teeth are misaligned), incorrect resting tongue placement and movement (resulting in tongue thrust), or teeth pushed outward in an overbite. These kinds of issues can cause poor chewing, difficulty with jaw placement, and possibly a need for orthodontic work.

So, should I stop my child from sucking their thumb?

Not necessarily. Thumb sucking as a soothing behaviour is totally normal for babies and will be totally fine for most toddlers to continue thumb sucking without lasting effects. You want to consider the amount of time the thumb is in the mouth. If it’s very often all throughout the day, we would work to keep their hands busy doing other things like playing. We don’t suggest making a big deal out of it. If you can, anticipate the thumb going into the mouth and then redirect it to holding a toy, playing, or singing a song together. Obviously, you won’t always be able to do this, but if you can minimize some of the time spent thumb-sucking throughout the day it may be helpful in the long run. Most kids will naturally stop on their own between the ages of 3 and 6.

But, if your child is between 3-5 and still sucking their thumb often, you may want to start gently guiding them to stop. We would start the transition to stopping long before they reach these ages because it may take a while. Again, as always, do what’s right for your family.

If you think it’s time to help your child stop sucking their thumb, HealthLink BC has some great ideas to get you started.

3 Simple & Effective Strategies

Explaining to your child why they should stop sucking their thumb (best for 5+)
Helping them to keep their hands busy while they’re transitioning (age 1+)
Offering lots of praise and rewards for stopping (age 2+)

And they also explain when and how to seek reinforcement from your doctor or dentist if thumb sucking goes on a little too long. You can read all of their tips and information here.

This guide, created by pediatric dentist, Dr. Helen Mo, also offers a lot of practical advice.

Questions about tooth formation and speech development?

Leave a comment below and we’ll help you find the answers you need!

Thumb Sucking and Speech Development