Breathing Through Your Nose:
Warms the incoming air to body temperature, the optimal temperature for the lungs.
Moisturizes the incoming air, providing the lungs with approximately a liter of moisture per day.
Filters the incoming air through the hairs and mucous membranes that line the nose to remove particles.
Stimulates secretion of healthy mucous to help keep the airways moist, preventing coughing and throat clearing.
Regulates the direction and velocity of the air stream to maximize exposure to the protective nasal mucosa, whose blanket of cilia provides a protective barrier against bacteria, chemical, or gaseous stimuli.
Keeps your sinus membranes lubricated and functioning well, lessening the chance of stagnation that can lead to sinus infections.
Facilitates the production of nitric oxide, an essential bronchodilator that also sterilizes the air in your sinuses on the way to your lungs.
Triggers the release of immunoglobulins (anti-bacterial molecules) that help to clean the incoming air and increase the functioning of your immune system.
Creates pressure differences between your lungs and nose, assuring the flow of air and oxygen to the heart and lungs.
Imposes a resistance to the flow of air that results in 10–20 percent more oxygen uptake, helping to maintain elasticity of the lungs and ultimately the effectiveness of the heart.
Minimizes loss of CO2 during exhalation, thereby allowing CO2 to do its job of reducing constriction in your airways and blood vessels, facilitating the release of oxygen from your red blood cells, and thus maximizing oxygen delivery to the other cells of your body.
In addition, breathing through your nose:
Heightens your sense of smell, linking it to the limbic system—the seat of your emotional body—to allow you to make more choices about how you feel about things you encounter in your immediate environment.
Maintains your sense of hearing by cleaning the environment around the inner auditory tube at the back of the upper throat, to keep it free from stagnating debris.
Regular nasal breathing helps keep the nasal passages open for all the benefits on this list. It also Brings air into your sphenoid sinuses to cool your pituitary gland and help regulate your body temperature.
Regulates sleep by reducing CO2 emissions, helping to keep your nervous and cardiovascular systems’ chemistry in balance.
Activates turning of the head and body from one side to the other during sleep, ensuring maximum rest and possibly reducing symptoms of backache, numbness, cramps and circulatory deficits that can occur from sleeping in only one position.
Activates healthy movement at several head and neck joints: the atlanto-occipital joint, the atlanto-axial joint, the sphenobasilar joint, and sutures of the facial and head bones— nourishing your central nervous system and helping to relax your neck and shoulders.
Moves the air past your nasal septum, slowing the movement of air and facilitating a more complete integration of the process of ventilation with other biological processes.
Provides any excess tears a clear passageway for drainage.
Channels the air past the structures that mark the center of your head, helping to keep you balanced and centered.
Stimulates formation of sinus growth in childhood through the movement of air.
And lastly—and maybe most importantly—breathing through your nose:
Reduces anxiety by regulating the speed of respiration and encouraging maximum inflation of your lungs, producing a calming effect.
Deepens your connection to yourself and helps bring your attention to the present moment.
Facilitates meditation and allows you to tap into your innate sense of well-being.