Why breathing through your nose is really important!

I have assessed over 3 ½ thousand patients using capnometry, a non-invasive and very scientific way of looking at breathing behaviour. About 70% of my patients don’t breathe properly!

One of the problems is that many patients I see, tend to be chronic mouth breathers, characterized by inhaling and exhaling primarily through the mouth and is considered to be an abnormal respiratory function.

Patients can become mouth breathers for a variety of reasons such as enlarged tonsils, rhinitis, tumours, infections, inflammatory disease, and abnormalities in nasal architecture. Another cause of chronic mouth breathing is improperly developed orofacial muscles from infancy due to factors such as bottle feeding, finger sucking and/or non-nutritive sucking, making those muscles weaker. Prolonged mouth breathing can lead to muscular and postural alterations, which may cause dentoskeletal changes. Consequently, the habit of breathing through the mouth, even without obstruction, alters the balance of facial muscles and causes facial skeletal changes.

Helping people change to become predominantly nose breathers will be an important part of retraining their breathing behaviour

Many healthcare professionals are unaware of the negative effects of chronic mouth breathing which can lead to changes in tongue and head position. With chronic mouth breathers, the location of tongue is down and backwards instead of up and forward in the palate. The tongue position influences the palatal development and, if not properly positioned in the palate, can result in a deep vaulted hard palate and a deviated septum contributing to mouth breathing, instead of a domed formation and properly formed septum. The tongue resting in the lower jaw can cause a forward head position. Every millimetre of forward head posture increases the weight of the head on the spine by approximately 4kg creating an adverse load on the cervical joints, induced by poor spinal, cervical, and scapular postures. Additionally, the forward head position may strain the deep postural-stabilizing muscles of the spine, reducing the performance of their functional postural-supporting role.

A significant problem with mouth breathing is the reduction of oxygen delivery on a cellular level, as many patients have low CO2, leading to a downward spiralling effect on sleep, stamina, and energy levels.  This effect is caused by inhaling too much oxygen and exhaling large amounts of carbon dioxide, needed for the transfer of oxygen from the haemoglobin molecule during respiration in the lungs. Breathing through the mouth also causes dryness of the oral and pharyngeal tissues and may lead to inflamed tonsils, tonsil stones, dry cough, swollen tongue, halitosis, and gingivitis. Mouth breathers also chew with their mouths open and swallow air, leading to gas, bloating, flatulence, and burping. In addition, lips become dry and weak because they do not stay closed to provide the necessary lip seal.

Additionally, mouth breathing can cause changes in sleep patterns, which can contribute to a decrease in immune defence cells and an increase in humoral serum values related to inflammatory mediators, indicating the occurrence of oxidative stress and an altered systemic inflammatory state. A reduction in the quality or quantity of sleep can result in biological and cognitive imbalance, potentially decreasing physical performance and the recovery process after exercise.  In addition, the decrease in immune defences cells puts patients at risk for contracting illnesses.

So why is nose breathing so important?

Nose breathing warms air as we inhale and adds moisture so decreasing drying and cooling in the lungs, a significant cause of exercise induced asthma. It filters the air reducing pollution. It adds resistance to the air stream and helps increase oxygenation uptake by maintaining the lungs elasticity (yes, it’s slightly harder to do than mouth breathing in the beginning).

The nasal cavities and paranasal sinuses are probably the largest source of endogenous NO (Nitric Oxide), not to be confused with N2O (Nitrous Oxide laughing gas) or NO2 (nitrogen dioxide a pollutant). NO is a potent vasodilator (a good thing), there is also research to suggest it acts as part of our immune system attacking bacteria and viruses and trying to keep us safe. There is also research suggesting that NO regulates lung function, including reducing pulmonary resistance and increases arterial oxygenation, making breathing more efficient.

The benefits of enhanced NO productivity include increased aerobic capacity, reduced hypertension, increased insulin sensitivity and glucose tolerance, capillarization and angiogenesis, and even long-term potentiation (LTP) associated with cellular models for learning and memory. An additional benefit of enhanced NO productivity is neurogenesis, which is the process by which new neurons form in the brain. Nitric oxide, through nasal breathing, helps to regulates autonomic functions like heart rate, respiration, blood pressure, and digestion along with mood, sleep cycle, fluid balance, and reproduction. The increase of blood flow derived from NO synthesis may improve the recovery processes after exercise.

As demands of physical activity increase, athletes may switch from breathing nasally to mouth and nose, or to breathing completely with their mouths. There is, however, no exact switching point, due to a wide variance in people’s breathing patterns and needs. At higher intensities of physical activity, nasal breathing cannot provide the volume of O₂ that oral breathing can, and less O₂ content will result in a decrease in athletic performance. On the other hand, while mouth breathing at high levels of exertions may result in hyperventilation, nasal breathing effectively reduces this state. The evidence, thus, still supports nasal breathing, even at higher levels of performance, as a more efficient mode, given that the same amount of mechanical work is completed at a lower metabolic cost compared with oral respiration. Using nasal expanders can, therefore, increase the capacity to sustain moderate to intense physical exertion during nasal breathing. If you’ve ever watched Roger Federer Play tennis you will know he is definitely a nose breather, very rarely opening his mouth despite the intensity of the game. I admire his temperament, his skill and his performance and I’m sure his breathing pattern is something to do with that.