Nasal Breathing

Nasal breathing is breathing through the nose. The importance of breathing through the nose rather than the mouth was recognised in the 19th century. Hendrik Zwaardemaker (1857-1930) studied this and invented a device to measure the amount of airflow through each nostril. This rhinomanometer used cold mirrors; more recent devices use acoustic technology.

It is often considered superior to mouth breathing for several reasons. Air travels to and from the external environment and the lungs through the sinuses, as opposed to the mouth. The sinuses do a better job of filtering the air as it enters the lungs. In addition, the smaller diameter of the sinuses create pressure in the lungs during exhalation, allowing the lungs to have more time to extract oxygen from them. When there is proper oxygen-carbon dioxide exchange, the blood will maintain a balanced pH. If carbon dioxide is lost too quickly, as in mouth breathing, oxygen absorption decreases. Nasal breathing is especially important in certain situations such as dehydration, cold weather, laryngitis, and when the throat is sore or dry because it does not dry the throat as much.

The air moves up the nose through the trachea, which is lined with cartilagenous rings, which then splits into 2 bronchi (singular bronchus). These then branch into bronchioles, which in turn branch off and end in alveoli.