Research shows that individuals who habitually breathe through the mouth are more likely than those who breathe through the nose to have sleep deprivation, fatigue, headaches and ADHD symptoms. In addition, research shows that breathing through the mouth instead of the nose can adversely affect brain function, facial growth and dental health. Your nasal passages are sinuses designed to prepare air for delivery to your lungs. They act as a humidifier, warming and moistening the air. They also remove debris and act as a first-line of defence against unfriendly microbes. But more importantly, nasal breathing helps oxygen flow via nitric oxide(NO) which is produced in the nasal sinuses by specific enzymes. It’s instrumental in delivering oxygen around the body efficiently because it regulates blood flow; increases arterial oxygen tension and reduces blood pressure.

Nitric oxide also has a vital role deep within your body’s cells by influencing platelet function, immunity and the nervous system.  It’s also important in homeostasis and the regulation of mitochondrial function. In addition, mouth breathing has been linked to sleep apnoea, metabolic syndrome and weight gain.