Is Mouth Breathing While You’re Sleeping Bad?

Dr. Angela Seabright

| 3 min read

Dr. Angela Seabright, D.O., is a board-certified fam...

If you’ve ever woken up from sleeping with an excessively dry mouth – or drool on your pillow – it may likely be a sign you were breathing through your mouth.
This happens when the body resorts to taking in new air through the mouth versus through the nose. This may be because the nose is congested, such as the case if you are sick or if you have allergies. This can also be caused by enlarged adenoids, which are glands above the roof of the mouth, or if you have a deviated septum or other structural blockage of the nose.
For individuals who occasionally breath through their mouths, this could cause short-term issues. But if mouth breathing is persistent, it could lead to bigger conditions – like sleep apnea – that may require treatment.

How is mouth breathing different than breathing through the nose?

The nose is built to provide the body with clean, warm and moist air.
When you breathe through your nose, the tiny hairs inside (called cilia) filter out things like dirt and pollution, allergens and insects. The nose also has internal structures to keep the air that you breath in moist. And by breathing in air through the nose, it gradually warms up as it travels through the body – making it easier for the tissues in the lungs to absorb.
The mouth does not provide these functions when you take in air. There are no hairs in the mouth to clean the air, and no structures to ensure the air is moist.

What are the symptoms of mouth breathing?

Children and adults often have the same symptoms of mouth breathing. Those can include:
  • Dry mouth, as breathing through your mouth can dry out the saliva that typically keeps the mouth moist
  • Bad breath, as without the saliva to keep the mouth moist, more bacteria can grow that cause a bad odor
  • Drool on pillows, as the saliva will drip out from the mouth when it is open during sleep
  • Dental problems, such as poor alignment and cavities
  • Snoring
  • Daytime sleepiness
Children may also have additional symptoms of mouth breathing, such as a specific pattern of facial development and behavioral problems.
Snoring, hoarseness, waking up tired and irritable and brain fog can also be signs of mouth breathing, as it can contribute to a poor night’s rest.

Why is mouth breathing bad?

Breathing through the nose instead of the mouth is always the preferred method, as it helps the body clean the air and keep it moist.
Mouth breathing prevents the body from keeping the mouth moist with saliva, which puts you at risk for dental issues including gingivitis and tooth cavities. Saliva contains minerals including calcium and phosphate which help keep teeth strong and to fight tooth decay. Without enough saliva, there is an increased risk for tooth decay or fungal infections in the mouth.
Mouth breathing puts individuals at a higher risk of sleep disorders, including sleep apnea. Sleep apnea is when breathing stops and starts during sleep.
For children, they may be more prone to developing a dental problem including malocclusion, as well as for developing obstructive sleep apnea.
If you or a loved one chronically breathes through their mouth while sleeping at night, talk with your health care provider about options for diagnosis and treatment. For children, unaddressed, chronic mouth breathing while sleeping can cause developmental issues that ultimately can affect their behavior. It’s important to address any concerns you have as early as possible.
MI Blues Perspectives is sponsored by Blue Cross Blue Shield of Michigan, a nonprofit, independent licensee of the Blue Cross Blue Shield Association