Breathing is an automatic process that sustains life, yet the way we breathe can have profound impacts on our health, well-being, and even our appearance. While many of us are unaware of the nuances between breathing through the nose versus the mouth, the differences are significant and can influence everything from dental health to stress management. This article explores the distinct pathways of mouth breathing and nose breathing, their respective drawbacks and benefits, and the best practices for breathwork and relaxation. 

Mouth Breathing: A Common but Potentially Harmful Habit

Mouth breathing, particularly when it becomes a chronic habit, has been linked to a variety of health issues. One of the primary concerns is that air inhaled through the mouth bypasses the natural filtration and humidification systems of the nasal cavities (1). The nose warms, moistens, and filters the air before it reaches the lungs, but when breathing through the mouth, this air enters the lungs unfiltered, dry, and cold, which can stress the respiratory system and exacerbate existing respiratory conditions (2).

Over time, chronic mouth breathing can lead to structural changes in the face. Observational studies have documented alterations such as a narrower face, a higher palate, and a retruded mandible, all of which can contribute to an altered facial appearance that is often perceived as less aesthetically pleasing (3). These changes are not merely cosmetic; they can have functional consequences, including dental problems like malocclusion, crowded teeth, and a predisposition to gum disease and cavities (3–6). The altered muscle dynamics around the jaw and lips can also lead to speech difficulties and an increased likelihood of conditions like sleep apnea and snoring, especially when mouth breathing occurs during sleep (6,7).

Children are particularly vulnerable to the negative effects of mouth breathing. Research suggests that more than half of school-aged children may be chronic mouth breathers (8,9), and a significant proportion of young children develop sleep-disordered breathing patterns by the age of six (10). These patterns are associated with cognitive and behavioral issues, including a higher prevalence of ADHD (11). Thus, it’s plausible that a portion of young children are misdiagnosed with ADHD while in fact, they may have sleep-related issues, which often portray similar symptoms (12). The importance of early detection and intervention cannot be overstated, as prolonged mouth breathing can lead to permanent facial and dental changes that require extensive treatment to correct. 

Nose Breathing: The Body’s Natural Breathing Mechanism

Nose breathing is how our bodies are naturally designed to take in air. The nasal passages perform several vital functions that contribute to overall respiratory health. The nose filters out dust, allergens, and other particles from the air, reducing the risk of respiratory infections and conditions like hay fever and asthma. Furthermore, the air inhaled through the nose is warmed and humidified, making it more comfortable and less irritating to the lungs (1).

Nose breathing also plays a critical role in the development and maintenance of facial structure. Proper nasal breathing encourages the formation of natural dental arches and straight, healthy teeth (13). The resistance created by the nasal passages forces the respiratory muscles, including the diaphragm, to work harder, which in turn stabilizes the spine and may help prevent injuries (14–17). Because of the resistance of nasal airways to the airstream, oxygen uptake can be 10–20% higher (18). 

One of the lesser-known benefits of nose breathing is its role in producing nitric oxide (NO), a molecule that is generated in the paranasal sinuses and inhaled into the lungs. Nitric oxide is a potent vasodilator and bronchodilator, meaning it helps widen blood vessels and airways, improving oxygen transport throughout the body (19,20). It also has antiviral and antibacterial properties, contributing to the body’s immune defense (19,21).

Breathing for Relaxation and Stress Relief 

In breathwork practices, the combination of inhaling through the nose and exhaling through the mouth, especially with pursed lips, is often emphasized. This method of breathing has been shown to activate the parasympathetic nervous system, which is responsible for the body’s “rest and digest” functions. By slowing the breath and controlling the exhalation, this technique promotes relaxation and helps reduce the body’s stress response (22). 

When you inhale through the nose, the air is filtered and warmed, as mentioned earlier, but this action also encourages deeper breaths that engage the diaphragm more effectively. Diaphragmatic breathing, where the diaphragm contracts and moves downward, allows the lungs to fill more completely with air. This deep breathing not only increases oxygen intake but also stimulates the vagus nerve, which plays a crucial role in regulating the parasympathetic nervous system (18).

Exhaling through the mouth with pursed lips further enhances this effect. Pursed-lip breathing creates a slight resistance to the airflow, which helps to slow down the exhalation process. This slower exhale increases the time it takes for the lungs to empty, thereby reducing the overall breathing rate. A slower breathing rate has been associated with lower heart rates and reduced blood pressure, both of which are indicators of a relaxed state. Moreover, the action of exhaling through pursed lips helps maintain positive airway pressure, preventing the collapse of the airways, which is especially beneficial for individuals with respiratory conditions like COPD (22). This technique can also be used in breathwork practices to help clear the mind, focus attention, and induce a meditative state, making it a powerful tool for managing stress and anxiety (18,22).

Applications in Daily Life

Incorporating this combined breathing approach into daily life can be highly beneficial, especially in situations of stress or anxiety. For instance, during moments of acute stress, consciously slowing your breath and practicing inhaling through the nose and exhaling through pursed lips can help calm the nervous system and bring a sense of control and calm. This technique is also useful in preparation for sleep, as it can help transition the body from a state of wakefulness to one of rest.

Additionally, this breathing method can be integrated into mindfulness practices such as yoga or meditation, where the focus on breath helps anchor the mind and reduce the impact of stress. The simplicity of this technique makes it accessible to everyone, regardless of fitness level or experience with breathwork.

Conclusion 

Breathing is an automatic process, but how we breathe can have far-reaching effects on our health and well-being. Chronic mouth breathing, while sometimes necessary in specific circumstances, is generally associated with a range of negative health outcomes, particularly when it becomes habitual. Nose breathing, by contrast, offers numerous benefits, from improved respiratory function to better dental health and enhanced immune protection. By adopting the combined approach of inhaling through the nose and exhaling through pursed lips, we can harness the power of our breath to promote relaxation, reduce stress, and enhance overall well-being.

Understanding the different impacts of mouth and nose breathing empowers us to make conscious choices about how we breathe. By adopting healthier breathing habits, we can support our body’s natural functions and improve our overall quality of life. 

Key takeaways: 

1. Chronic mouth breathing is generally harmful: It can lead to various health issues, including altered facial structure, dental problems, respiratory conditions, and sleep-disordered breathing. 

2. Mouth breathing during physical activity may have negative effects: It can contribute to exercise-induced bronchoconstriction and lead to inefficient breathing, increased water loss, and decreased endurance. 

3. Nose breathing should be the default mode of breathing: It naturally filters, humidifies, and warms the air, protecting the respiratory system and promoting overall health. 

4. Nose breathing supports better oxygen uptake and immune function: It increases nitric oxide production, which improves oxygen transport, dilates blood vessels, and has antiviral and antibacterial properties. 

5. Doing breathwork using the combined approach: This method can be used in daily life to calm the nervous system, lower heart rate and blood pressure, promote relaxation, reduce stress, help manage anxiety, and improve mental focus and sleep quality.