Nasal breathing

The nose prepares the inspired air

Air passes through the nasal cavities before arriving further down in the respiratory tract. There it is warmed, humidified and partially freed of particles thanks to the surfaces and secretions of the nose. Mouth breathing bypasses much of this preparation. This explains the functional interest of the nasal passage during calm breathing.

Less air passing through the mouth

Breathing regularly through your mouth can contribute to dryness, especially at night. Reducing this air passage can therefore improve comfort when this cause is present. For appearance, this mainly ties in with lip care and a relaxed mouth at rest. Dryness can, however, come from other factors: nasal breathing does not replace all oral care.

The role of nitric oxide

The sinuses produce nitric oxide, part of which enters the air breathed in through the nose. This molecule is involved in different physiological functions, particularly vascular. Its presence constitutes a real difference between the respiratory tract, but does not allow us to deduce that a healthy person lacks oxygen as soon as they breathe through the mouth or that they will automatically gain a better complexion.

During growth, an important association

In children and adolescents, studies associate chronic mouth breathing with certain differences in jaw position, facial height and dental occlusion. Growth and resting postures make this period special. However, this work does not prove that breathing alone explains each facial shape: obstruction, anatomy and development can interact.

In adults, more modest expectations

A recent review in adults reports possible links with posture and the functioning of the muscles of mastication, but judges the evidence to be of very low certainty. It does not demonstrate that learning to breathe through your nose reshapes the bones of the face. The result to be sought remains comfortable breathing and a resting mouth less open out of habit, with limited aesthetic interest.