Researchers point to benefits of nose breathing
Does it matter whether you breathe through your nose or your mouth? Here’s how three researchers answer.
Eddie Weitzberg, Professor of Anaesthesiology and Intensive Care Medicine:
“Yes. Unlike the mouth, the nose acts as an air-conditioning system with three important functions. The nasal hairs and mucous membranes in the nose trap dust and particles, and the air is warmed and humidified before it reaches the lungs, which is beneficial for the airways. Research also shows that the gas molecule nitric oxide (NO) is produced in our sinuses. This gas has vasodilatory and antibactericidal properties, and when you inhale through the nose, NO is drawn out of the sinuses and travels down to the lungs, with a positive effect on blood oxygenation.”
Marian Papp, yoga teacher and researcher in yoga:
“Yes. Yoga exercises are performed at a lower intensity than, for example, running, and in that case, nasal breathing is an advantage. It automatically results in slower, deeper breaths, increases the activation of the diaphragm and counteracts dysfunctional breathing, where one breathes too quickly or shallowly. At the same time, the air is warmed, moistened and filtered, and the body absorbs nitric oxide, which has a vasodilatory effect. Nasal breathing stimulates the parasympathetic nervous system, which can lower the heart rate and blood pressure and contribute to mental calm. Research also shows that nasal breathing affects brain activity and is linked to more slow-wave brain activity. In yoga, alternate nostril breathing is sometimes used, where you breathe through one nostril at a time, which increases breathing resistance and results in even slower breathing.”
Artin Arshamian, researcher in cognitive neuroscience:
“Yes. We have shown that breathing affects how memories are consolidated, that is, how they are strengthened after being encoded, and that the effect is stronger when breathing through the nose. Breathing also appears to affect cognition and perception in several ways. New findings from our group show that breathing, whether it occurs through the nose or the mouth, controls how the pupil changes. When you breathe in, the pupil constricts, and when you breathe out, it is at its widest. We now want to investigate whether this affects our vision.”