Mouth Breathing: Signs, Risks and How to Fix It

Mouth Breathing: Signs, Risks and How to Fix It
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Mouth Breathing: Signs, Risks and How to Fix ItClinical Content Reviewed by Dr. Jay Khorsandi, DDS
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Table of Contents

  1. What Is Mouth Breathing?
  2. Causes
  3. Symptoms
  4. Oral Health Complications
  5. Treatment Options
  6. Mouth Breathing vs. Nose Breathing
  7. References
Irregularities within the nasal cavity or sinus issues usually explain why someone is mouth breathing. Nasal breathing is preferred by medical experts. Snoring, bad breath and fatigue are primary symptoms of mouth breathing.

What Is Mouth Breathing?

Mouth breathing is an abnormal breathing condition in which you breathe using your mouth most of the time.

Research shows that mouth breathing is one of the main causes of sleep disorders, which have a negative impact on overall health.

Causes of Mouth Breathing

Any irritation or blockage of the nasal passages, tongue or mouth can cause mouth breathing. The most common causes are environmental allergies, nasal polyps and a deviated septum.

Nasal Allergies

Allergies often inflame, congest or block your nasal passages, leading to mouth breathing. Sometimes the allergy may linger, entrenching mouth breathing as a habit even after the allergy is gone. 

Nasal Polyps

Polyps grow in your nose lining from long-term irritation and swelling from allergies and infections. Smaller polyps may not have much effect, but large polyps can block your sinuses and nasal cavities. This blockage can make you short of breath, necessitating mouth breathing. 

Deviated Septum

A deviated septum is when the nasal septum that separates your nostrils moves too far to one side. It can be a genetic condition, but it usually occurs because of an acute facial or nose injury.

With the septum pushed too far to one side, breathing through both nasal passages becomes difficult — and sometimes impossible. For someone with a deviated septum to draw in a breath, the mouth is all-important.

Surgery is the only way to repair a deviated septum, but medications sometimes help open the passageway.

Enlarged Adenoids and Tonsils

Adenoids and tonsils behind the nose and mouth can become inflamed and swollen, blocking airways, mainly when the body fights an infection. The blockage results in snoring, restlessness when breathing, and mouth breathing

Tongue-tie (Ankyloglossia)

With an unresolved tongue-tie, the thick and tight tissue restricts the movement of the tongue. This can restrict achieving the proper position of the tongue towards the front and top of your mouth and may further keep the tongue pulled more towards the back of your throat and increasing the likelihood of potential snoring or sleep apnea.

According to an online survey conducted by the Breathe Right® brand, 61 percent of the respondents identify themselves as mouth breathers.


Symptoms of mouth breathing include fatigue, halitosis and heavy snoring. Another symptom is if you find yourself more prone to getting ear infections.


If you engage in mouth breathing, you will not experience deep sleep because of uneven breathing patterns. Lack of quality sleep causes accumulated fatigue in the daytime, becoming chronic. In children, it can be evident in behavioral issues. 

Bad breath (Halitosis)

Breathing through the mouth exposes and dries out the tissues of your mouth. In addition, an open mouth cannot make the air passing through it moist or warm. These circumstances and the lack of saliva to clear the debris left by food result in bad breath. 

Heavy snoring

Snoring results from the vibration of loose and relaxed tissue around your soft palate and airway while you sleep. Obstruction from blockage and polyps can also result in mouth breathing and sleep apnea. 

Frequent Sinus and Ear Infections

A tongue-tie leaves the mouth open, preventing fluid from draining from your sinuses. That results in frequent infection in the maxillary, ocular, nasal, and ear sinuses, accompanied by breathing problems.

Oral Health Complications of Mouth Breathing

Tooth decay and gum inflammation

Sleeping with your mouth open causes dry mouth and natural bacteria changes, which results in cavities and gum disease. The dried gums also get irritated due to insufficient saliva lubrication, leading to sores. 

Misaligned Teeth

The tongue acts as a palatal expander during human growth and development. When it cannot rest on the top of the mouth, the mouth remains open, and the jaws develop narrower than usual. This growth results in gummy smiles, teeth crowding, and prominent front teeth

Dry Mouth

When it is necessary to breathe through your mouth, the mouth lining dries out. The condition can result in mouth sores, problems in swallowing, cracked lips, and yeast infections in the mouth. It also makes you more prone to upper respiratory infections.

Treatment Options

Treatment of mouth breathing varies because of the age of the person who has it and for how long. While prolonged mouth breathing can make nose breathing difficult, there are effective treatments, including: 

  • Targeted exercise: You can reverse the early stages of mouth breathing by targeting breathing through the nose during the day.
  • Clean environment: Ensuring that your house is constantly clean can prevent allergens inhalation. Air conditioning can warm the air in your home. 
  • Saline mists: A saline mist combats nasal congestion. Use it when traveling to a new environment. 
  • Surgery: If the mouth breathing is from enlarged tonsils, adenoids, or polyps, minor surgery to remove them is ideal.
  • Sleep posture: When sleeping, elevate your head with pillows to allow the flow of fluids by gravity. This posture prevents congestion, which triggers mouth breathing.
  • Relieve stress: Yoga therapy and meditation will be helpful if stress triggers your mouth breathing.

Mouth Breathing vs. Nose Breathing

Nasal breathing provides a system that moistens, filters and warms the air before reaching the lungs. The air gets infused with nitric oxide in the nose, which helps destroy some micro-organisms and improves oxygen uptake

On the other hand, mouth breathing allows you to breathe in up to three times more air than nasal breathing. The large volume can trigger inflammation because of a higher carbon dioxide concentration than required. You breathe in dry, unfiltered air filled with debris and allergens. 

Benefits of nasal breathing include: 


Mouth Breathing. (April 2022). Cleveland Clinic.

Enlarged Adenoids. (August 2019). Mount Sinai, New York.

Growth and Mouth Breathers. (March-April 2019). Science Direct

Effects of mouth breathing on hippocampal activity examined by 3T fMRI. (April 2016). Stanford University.

Does breathing through my mouth affect my dental health? (August 2015). Harvard Medical School.

Nasal nitric oxide in man. (1999). British Medical Journal.

Mouth Breathing. UMass Chan Medical School.

Disclaimer: This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to serve as dental or other professional health advice and is not intended to be used for diagnosis or treatment of any condition or symptom. You should consult a dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.