Why Nasal Breathing Matters More Than We Think
- Mar 26
- 6 min read
Updated: Mar 28
Alicia Lewis is a registered dental hygienist, myofunctional therapist, and founder of Paradigm Dental Therapy in London, Ontario. With over 25 years of experience, she specializes in airway-focused care, breathing, and functional oral health to support lifelong wellness.
Breathing is a fundamental physiological process that plays a critical role in overall health, yet the mode of breathing, nasal versus oral, is often overlooked in clinical practice. Nasal breathing supports optimal respiratory function through filtration, humidification, and the production of nitric oxide, which enhances oxygen uptake and immune defense. In contrast, chronic mouth breathing is associated with airway dysfunction, sleep-disordered breathing, and altered craniofacial development, particularly in children. Emerging evidence from sleep medicine, orthodontics, and respiratory physiology highlights the far-reaching implications of breathing patterns on sleep quality, cognitive development, and long-term health outcomes. This article reviews the physiological advantages of nasal breathing, the consequences of mouth breathing, and the role of myofunctional therapy in restoring optimal airway function.
Breathing is an automatic and continuous function, occurring approximately 20,000 times per day. Despite its constancy, the quality and route of breathing significantly influence physiological health. Nasal breathing represents the body’s optimal mode of respiration, yet mouth breathing remains prevalent, particularly among children.
Historically, breathing patterns have received limited attention in clinical practice. However, growing evidence across multiple disciplines, including sleep medicine, dentistry, and respiratory physiology, demonstrates that dysfunctional breathing patterns can contribute to impaired sleep, altered development, and systemic health concerns.[1] [2]
The nose: A specialized organ for respiration
The human nose is uniquely designed to optimize respiratory function. As air passes through the nasal cavity, it is filtered, warmed, and humidified before reaching the lower airway.[3] This conditioning process protects delicate lung tissues and improves gas exchange efficiency.
A key physiological advantage of nasal breathing is the production of nitric oxide (NO) within the paranasal sinuses. Nitric oxide acts as a vasodilator and bronchodilator, enhancing pulmonary blood flow and oxygen uptake.[4] [5] Additionally, nitric oxide exhibits antimicrobial properties, contributing to immune defense within the respiratory tract.
These mechanisms collectively support more efficient oxygen delivery compared to mouth breathing, which bypasses these critical processes.
Prevalence and causes of mouth breathing
Despite the benefits of nasal respiration, chronic mouth breathing is common. Epidemiological data suggest that approximately 10-25% of children exhibit habitual mouth breathing patterns.[6]
Common contributing factors include:
Nasal obstruction
Allergic rhinitis
Adenotonsillar hypertrophy
Chronic upper airway congestion
While mouth breathing may initially arise as a compensatory response to obstruction, it can persist as a learned behavior even after the underlying issue resolves.
Unlike nasal breathing, mouth breathing allows unfiltered, dry air to enter the airway, potentially contributing to irritation, inflammation, and increased susceptibility to respiratory conditions.
Snoring and sleep-disordered breathing
Snoring is often considered benign. However, it is increasingly recognized as an indicator of airway dysfunction. It results from turbulent airflow and vibration of soft tissues within a narrowed airway.
In pediatric populations:
3-12% of children snore regularly
1-5% develop obstructive sleep apnea (OSA)
OSA is characterized by repeated episodes of partial or complete airway obstruction during sleep, leading to intermittent hypoxia and sleep fragmentation.
Children with sleep-disordered breathing frequently exhibit mouth breathing and altered orofacial muscle function, which can contribute to airway instability.[7]
Impact of sleep disruption on cognitive and behavioral outcomes
Sleep plays a vital role in physical and neurological development. Deep (slow wave) sleep is essential for growth hormone release and tissue repair, while rapid eye movement (REM) sleep supports learning, memory consolidation, and emotional regulation.[8]
Disrupted breathing during sleep leads to repeated micro-arousals, fragmenting the sleep cycle and reducing time spent in restorative stages.
Research indicates that children with sleep-disordered breathing are at increased risk for:
Impaired attention and executive function
Behavioral challenges
Poor academic performance
Additionally, intermittent hypoxia and sleep fragmentation may negatively impact brain development and neurocognitive outcomes.[9]
Craniofacial development and breathing patterns
Breathing patterns play a critical role in craniofacial growth. Nasal breathing promotes proper tongue posture against the palate, supporting normal development of the maxilla and dental arches.
In contrast, chronic mouth breathing is associated with:
Low tongue posture
Narrow maxillary arch
Increased lower facial height
Dental crowding
These structural changes may further compromise the airway, creating a cyclical relationship between airway dysfunction and craniofacial development.
Myofunctional therapy and airway rehabilitation
Myofunctional therapy has emerged as a valuable intervention for addressing dysfunctional breathing patterns. This therapy involves targeted exercises designed to improve the strength and coordination of the orofacial muscles.
Key goals include:
Establishing nasal breathing
Promoting proper tongue posture
Achieving lip seal
Improving swallowing patterns
A randomized controlled trial demonstrated that oropharyngeal exercises reduced the severity of obstructive sleep apnea by approximately 50% in adults.[10]
Further evidence from a systematic review supports the role of myofunctional therapy in reducing apnea severity, improving oxygen saturation, and decreasing snoring.[11]
These findings highlight the importance of addressing both structural and functional components of airway health.
Clinical implications and early identification
Early recognition of airway dysfunction is essential, particularly in pediatric populations.
Common clinical signs include:
Habitual snoring
Mouth breathing
Restless or fragmented sleep
Bedwetting beyond expected age
Daytime fatigue or hyperactivity
Difficulty concentrating
These symptoms are often overlooked or misattributed but may indicate underlying sleep-disordered breathing.
Interdisciplinary collaboration among dental professionals, physicians, and sleep specialists is critical for early diagnosis and intervention.
Conclusion
Breathing is foundational to health, yet its functional quality is frequently underestimated. Nasal breathing supports optimal respiratory physiology, sleep quality, and craniofacial development, while chronic mouth breathing is associated with a range of adverse outcomes.
Emerging research underscores the importance of recognizing breathing patterns as a key determinant of health across the lifespan. Clinicians are increasingly called to identify and address airway dysfunction early to support optimal development and long-term well-being.
Although snoring and mouth breathing are common, they should not be considered normal. Early intervention has the potential to significantly improve health outcomes, particularly in growing children.
Read more from Alicia Lewis
Alicia Lewis, Entrepreneur, Educator, RDH, MFT
Alicia Lewis is a registered dental hygienist and myofunctional therapist with more than 25 years of experience in oral health, airway function, and patient-centered care. As the founder of Paradigm Dental Therapy in London, she is passionate about helping patients and professionals understand the connection between breathing, oral function, and overall wellness. Her work blends clinical expertise, education, and functional therapy to support lasting health outcomes. Through her writing and teaching, Alicia empowers readers with practical insights that transform the way they view dental care and whole-body health.
References
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[8] Carskadon, M. A., & Dement, W. C. (2011).Normal human sleep: An overview. In M. H. Kryger, T. Roth, & W. C. Dement (Eds.), Principles and practice of sleep medicine (5th ed., pp. 160-26). Elsevier Saunders.
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[5] Lundberg, J. O. N., & Weitzberg, E. (1999). Nasal nitric oxide in man. Thorax, 54 (10), 947–952.
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