Breathing through the nose has many benefits, whilst breathing through the mouth, has many negatives.
There are some researchers who believe that mouth breathing and associated hyperventilation causes or exacerbates asthma, high blood pressure, heart disease, and many other medical problems.
It is strongly recommended, whenever possible - deviated septum and small nostrils may make it impractical or more difficult – to practice nose breathing 24/7. Let us note a few direct aspects:
The lungs are a primary source of our energy level. They extract oxygen from the air we breathe primarily on exhalation. As the nostrils are smaller then the mouth, air exhaled through the nose creates a back pressure on exhalation. It slows the escape of air so that the lungs have more time to extract oxygen from them. When there is a 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.
The transport (afferent) of 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.
In addition, when mouth breathing, the brain believes that 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, automatically governing the speed process of the breathing. Proper nose breathing reduces hypertension and stress for most people.
The nostrils and sinuses filter and warm the air going into the lungs. Breathing through the mouth bypasses this function. 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.
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, de-humidifying, and smelling the air.
Maintaining a keen sense of smell is very important for enjoying life and for safety and social acceptance. Think of all the beautiful smells we enjoy with our nose. Smell influences our behavior, our memories, and many autonomic nervous system functions which are below the level of conscious awareness.
This is because the receptors in the nose, known as olfactory bulbs, are direct extensions of a part of the brain known as the hypothalamus. The hypothalamus, also known as the Brain's brain, is responsible for many functions in our bodies, particularly those that we consider automatic, such as: heartbeat, blood pressure, thirst, appetite, and of course, the cycles of sleeping a waking. The hypothalamus is also responsible for generating chemicals that influence memory and emotion.
Upper Airway Resistance Syndrome, the new medical description for what most of us call snoring, is a problem for about 90 million Americans. Besides being a major social problem and irritant to others, it can also lead to major medical problems if snoring and mouth breathing combine to cause irregular breathing during sleep.
What you do during waking hours carries over into sleep. Therefore mouth breathing inhaling or exhaling will increase the chances of mouth breathing during sleep.
Early research indicated that nose breathing imposes approximately 50 percent more resistance to the air stream in normal individuals than does mouth breathing, resulting in 10-20 percent more O2 uptake. So it is believed that there must be adequate nasal resistance to maintain adequate elasticity of the lungs.
Breathing through the mouth with the nose obstructed usually imposes too little resistance and can lead to micro-areas of poor ventilation in the lungs (atelactasis). Many years of breathing against excessive resistance as with nasal obstruction, may cause micro areas of poor ventilation (emphysema).
Body temperature may even be influenced by the temperature of expired air.
The work load of lung movement doubled with nose breathing, creating a mild resistance training effect.
Training yourself to nose breathe during your waking hours can help the way you breathe while sleeping.
There is less chance of being susceptible to the common cold in nose breathing. The mucous (white blood cells that kill germs) membrane lining the nose extends all the way from the inner linings of the nostrils down the trachea to the bronchi the directly enters the lungs. Germs seem to get caught and die in the mucous.
Nose Breathing must be one of the more simple disciplines that we can try to adapt and make part of our lifestyle. It is a non-invasive habit, can be adapted by everyone and provides numerous benefits to the whole human system. Don’t be impatient, but rather enjoy the new sensation that you will observe and feel. It is well worth the effort.