Why Nose Breathing is important?

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Breathing through the nose has many benefits. One of the first lessons in the Yogi Science of Breathe, is to learn how to breathe through the nostrils, and to overcome the common practice of mouth-breathing. Many of the diseases to which civilized man is subject are undoubtedly caused by this common habit of mouth breathing. Many contagious diseases are contracted by the disgusting habit of mouth-breathing, and many cases of cold and catarrhal affections are also attributable to the same cause. Breathing through the mouth has many negatives.
Each nostril is innervated by five cranial nerves from a different side of the brain. Each nostril functions independently and synergistically in filtering, warming, moisturizing, dehumidifying, and smelling the air. The nostrils and sinuses filter and warm the air going into the lungs. The mouth breather bypasses this. The sinuses produce nitric oxide (NO) which is a pollutant but harmful to bacteria in small doses. Mouth breathing also accelerates water loss increasing possible dehydration.
Any opportunity for mouth breathing inhaling or exhaling will increase the chances of mouth breathing during sleep. Hospital studies have established that nocturnal mouth breathing is a primary cause of loud snoring. Snoring is a precursor to sleep apnea and apnea a precursor to heart attacks and dying in one's sleep. Also, when mouth breathing, the brain thinks carbon dioxide is being lost too quickly and sensing this, will stimulate the goblet cells to produce mucous, slow the breathing and cause constriction of blood vessels. Breathing through the nose also limits air intake and forces one to slow down. Proper nose breathing reduces hypertension and stress for most people. Kind of like a speed control (governor) on a car engine.
Afferent stimuli from the nerves that regulate breathing are in the nasal passages. The inhaled air passing through the nasal mucosa carries the stimuli to the reflex nerves that control breathing. Mouth breathing bypasses the nasal mucosa and makes regular breathing difficult. During sleep, it predisposes one to loud snoring and irregular breathing and can lead to a serious condition called Sleep Apnea and heart conditions.
The lungs are a primary source of our energy level. They extract oxygen from the air we breathe primarily on the exhale. Because the nostrils are smaller then the mouth, air exhaled through the nose creates back pressure when one exhales. It slows the air escape so the lungs 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 is decreased. So Athma-Pure Founder believes in Nose Breathing that is better than Mouth Breathing.