Open Mouth Breathing & Chewing

Have you ever noticed someone chewing with their mouth open—not just because they’re being rude, but because they have to? Open mouth breathing can have a much bigger impact on chewing than most people realize, and it all comes down to how the mouth and nose are connected.

The Mouth, the Nose & the Forgotten Connection

Most people don’t think about it, but the roof of your mouth (your hard palate) is also the floor of your nose. That means any changes to the shape or function of the palate can directly affect nasal breathing, and vice versa.

When someone primarily breathes through their mouth instead of their nose, a few things start happening:

1. The tongue sits low in the mouth instead of resting against the palate. This is a problem because the tongue plays a major role in shaping the hard palate during childhood. When the tongue is not in its ideal resting position, the palate may develop into a high and narrow shape rather than a broad, U-shaped arch (Mason, 2005).
2. The palate can become high and narrow, which reduces nasal airway space. A narrow palate means less room for air to pass through the nasal cavity, making it even harder to breathe through the nose. This creates a cycle where nasal breathing becomes more difficult, reinforcing the habit of open mouth breathing (Huang et al., 2015).
3. Chewing efficiency is affected because the tongue is essential for coordinating the movement of food. When the tongue sits low, it struggles to keep food properly positioned on the molars, making chewing slower, less effective, and more tiring (Gunjal et al., 2019).

Over time, these changes don’t just impact breathing—they influence speech, sleep quality, and overall oral function.

How Open Mouth Breathing Affects Chewing

Chewing is a complex process that requires precise coordination of the tongue, lips, jaw, and cheeks. When someone breathes through their mouth while chewing, several challenges arise:

1. The Lips Can’t Fully Seal

Chewing with the lips closed helps create the necessary intraoral pressure to manage food efficiently. But when someone habitually breathes through their mouth, keeping the lips sealed can feel unnatural or even impossible. As a result:

• Food particles may escape while chewing, leading to messier eating habits.
• Individuals may need to take frequent breaks to breathe, which can slow down mealtime.
• The lack of lip closure can contribute to weak orofacial muscles over time (Grosjean et al., 2022).

2. The Tongue May Not Be in the Right Position

The tongue plays a major role in moving food around the mouth, positioning it between the teeth, and helping with bolus formation before swallowing. When mouth breathing becomes habitual:

• The tongue tends to sit lower in the mouth, making it harder to move food efficiently.
• Food may not be chewed thoroughly, increasing the risk of choking or digestive issues (Barth et al., 2020).
• The tongue may compensate with extra movements, leading to inefficient chewing patterns and jaw fatigue.

3. Chewing Becomes Noisier or More Effortful

Efficient chewing requires the coordinated action of multiple muscle groups. When nasal breathing is compromised:

• The jaw and tongue may have to work harder to compensate for poor muscle coordination.
• Chewing sounds may be louder due to excessive mouth movement.
• Prolonged chewing may occur due to difficulties in processing food effectively (Grosjean et al., 2022).

Children who struggle with mouth breathing often develop compensatory habits that persist into adulthood. Addressing these issues early can help improve overall feeding skills and prevent long-term oral motor difficulties.

What Can Be Done?

If mouth breathing is affecting chewing, addressing the underlying cause is key. The good news? There are several ways to improve nasal breathing and oral function.

1. Encouraging Nasal Breathing

Nasal breathing is the body’s preferred way to breathe, as it filters and humidifies air while also supporting proper oral posture. Strategies to promote nasal breathing include:

• Identifying and treating underlying causes, such as allergies, enlarged adenoids, or chronic congestion (Guilleminault et al., 2016).
• Using nasal breathing exercises to strengthen airway muscles and improve breath control.
• Creating awareness about mouth posture and the importance of keeping the lips closed at rest.

2. Orofacial Myofunctional Therapy (OMT)

OMT is a specialized therapy that focuses on retraining the muscles of the face and mouth. It can help with:

• Correcting tongue posture to support proper palate development.
• Strengthening lip and cheek muscles to aid in chewing and swallowing.
• Encouraging better oral habits that reduce mouth breathing over time (Hanson & Mason, 2003).

3. Addressing Structural Concerns

For some individuals, structural issues may need to be addressed before functional improvements can take place. This could include:

• Assessing for a high or narrow palate and considering palatal expansion if necessary (Sutthiprapaporn et al., 2008).
• Evaluating for a tongue tie (ankyloglossia) that may be restricting tongue movement.
• Seeking an evaluation from an ENT specialist, dentist, or orthodontist to determine if additional interventions are needed.

Chewing isn’t just about the teeth—it’s a full-team effort between the tongue, lips, and jaw, all influenced by breathing. If  your child struggles with messy eating, prolonged chewing, or difficulty managing food, it might be worth looking into breathing patterns. After all, how we breathe affects everything—even something as simple as eating a meal.

References

• Barth, C., Martin, C., & Morawska, A. (2020). The association between feeding difficulties and oral motor function in children. Journal of Pediatric Gastroenterology and Nutrition, 71(5), 645-652.
• Grosjean, B., Leung, A., & Tam, C. (2022). Impact of mouth breathing on oral function and speech development: A systematic review. International Journal of Pediatric Otorhinolaryngology, 156, 111204.
• Guilleminault, C., Huang, Y. S., Monteyrol, P. J., Sato, R., Quo, S., & Lin, C. H. (2016). The ongoing effects of mouth breathing on sleep, health, and quality of life: A clinical review. Journal of Clinical Sleep Medicine, 12(5), 747-755.
• Gunjal, S., Nagarajappa, R., Sharda, A. J., Asawa, K., & Tak, M. (2019). Effect of tongue posture on the development of the palate in children: A longitudinal study. European Archives of Pediatric Dentistry, 20(3), 233-239.
• Hanson, M. L., & Mason, R. M. (2003). Orofacial myology: International perspectives. International Journal of Orofacial Myology, 29, 21-32.
• Huang, Y. S., Guilleminault, C., Monteyrol, P. J., Sato, R., & Quo, S. (2015). Effects of mouth breathing on craniofacial growth. Journal of Clinical Pediatric Dentistry, 39(3), 259-267.
• Mason, R. M. (2005). A retrospective and prospective view of orofacial myology. International Journal of Orofacial Myology, 31, 5-14.
• Sutthiprapaporn, P., Kominami, S., & Seki, K. (2008). Palatal expansion in young children: Impact on airway development. European Journal of Orthodontics, 30(3), 269-273.