Breathe Better, Live Better: Why The Mouth Is a Poor Substitute For The Nose

By Dr. Emily Watson

Most people don’t give a lot of thought to breathing. It’s just something they do naturally and effortlessly.

So it can come as a surprise when they learn they are doing it wrong — and may have been doing it wrong since early childhood.

This isn’t true of everyone, of course, but too many of us breathe through our mouths, even though it’s the nose that was specially designed for the task. Some people might shrug that off. No big deal, right? Their lungs are getting the air. What possible difference could it make whether that air finds its way to the lungs through one pathway as opposed to another?

But how air enters and leaves our bodies does indeed make a difference — a significant difference with far-reaching consequences to our health and to the structure of our jaws.

For one thing, the nose has filtering capabilities that the mouth does not. Mucus in the nose traps dust particles, bacteria, and other pollutants before they can make their way to our lungs. Those tiny hairs in the nose, which are called cilia, then sweep that mucus back into your throat, where it goes to your stomach and is neutralized. Another way the nose is a superior breathing instrument is that it humidifies dry air, keeping your airways moist, and it warms cold air, bringing the air to body temperature before it reaches your lungs.

If you breathe through your mouth and that filtering and regulating doesn’t happen. The air goes straight to the lungs — carrying any dust, bacteria, and additional pollutants right along with it. The unfiltered air can also cause the tonsils and adenoids to enlarge.

Another problem is that mouth breathing over time affects facial growth and development, as well as the position of the teeth. Additionally, mouth breathing causes the mouth to become dry, leading to increased plaque accumulation on the teeth, creating a higher risk for cavities and gingivitis (inflammation of the gums). In other words, mouth breathing can lead to a swarm of dental problems in years to come, potentially requiring extensive orthodontic work or, in difficult situations, jaw surgery.

This is why it’s important for parents to correct their children early if they see that they are breathing through their mouths. Even with babies, I suggest that parents gently close the mouth if they see them breathing through it, hopefully heading off any unwelcome situations in the future. If the mouth-breathing problem persists, have the child examined to see if there’s an underlying health reason that’s causing them to favor the mouth over the nose, such as enlarged tonsils or adenoids that create an obstruction.

To get an idea of what’s going on with mouth breathing that leads to so much trouble, try this experiment. First, take a moment to become aware of your breathing and concentrate on what you are doing. Then breathe through your nostrils only. You will notice that your lips are together, and your tongue touches the roof of your mouth.

Now breathe through your mouth. With your lips widened, your tongue drops to the bottom of your mouth. If mouth breathing becomes habitual, this low-resting tongue posture can lead to an overbite if the tongue is toward the back of the mouth and an underbite if the tongue is toward the front of the mouth.

As an orthodontist, I’ve seen the results of mouth breathing play out with patients, but I’ve also experienced it as a mother. My daughter, Grace, was a chronic mouth breather who was developing an underbite. Over time, her upper jaw would have become too narrow and underdeveloped, and her underbite could have gotten worse. She could have potentially needed jaw surgery when she was older. To prevent this, when she was 4, we took steps to widen her jaws and eliminate her underbite, allowing the skeletal issue to correct and create adequate space for all of her permanent teeth, eliminating the need for future surgery. As time passes, all she will need is one simple round of braces.

And that’s just one example of how mouth breathing causes problems or can be the symptom of a problem. In a subsequent article, I will explore this topic more.

But in the meantime, the good news is that it’s possible to intervene early so that minor issues don’t develop into more serious ones.