Breathing through the nose is the body's natural and preferred way of obtaining oxygen. Nasal breathing filters, warms, and humidifies air, while also promoting optimal oxygen and carbon dioxide exchange in the lungs. Unfortunately, mouth breathing bypasses these beneficial functions and can lead to a range of health issues. 

When people breathe through their mouths while sleeping, they may experience dry mouth, increased snoring, and a higher likelihood of developing sleep apnea1. Moreover, mouth breathing is associated with a higher risk of gum disease,2 bad breath, throat and respiratory infections3, and poor sleep quality. 

Common causes of mouth breathing include the following: 

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