20.05.2026
Mouth breathing and snoring are closely connected, and for many people, addressing one is the key to resolving the other. While snoring can have several causes, mouth breathing snoring is a particularly common pattern, and understanding the mechanism makes it much easier to find an effective solution.
Dr. Aditi Desai, President of the British Society of Dental Sleep Medicine, explains the relationship between mouth breathing and snoring, the reasons people breathe through their mouths during sleep, and the most effective approaches to treatment.
How Mouth Breathing Causes Snoring
The Role of the Upper Airway
When you breathe through your nose during sleep, air follows a controlled path through the nasal passages and down into the throat. The soft tissues of the upper airway remain relatively stable because the airflow is regulated and the tongue and jaw tend to stay in a more forward position.
Mouth breathing changes this dynamic entirely. When the mouth falls open, the tongue drops back toward the throat, the soft palate sags, and the uvula hangs lower. This narrows the airway significantly, and as air passes through at speed, the loose tissue vibrates. That vibration is what produces snoring.
So does mouth breathing cause snoring? Yes. Snoring and mouth breathing are directly connected through this anatomical sequence, and it is why many people who sleep with their mouths open snore consistently, regardless of other factors.
Why Mouth Breathing Makes Snoring Worse
Nasal breathing creates a slight resistance that helps regulate airflow. When you breathe through your mouth instead, air moves faster and more turbulently, which increases the vibration of soft palate and throat tissues. This often produces louder and more persistent snoring.
Mouth breathing also dries out the throat, causing the mucous membranes to become irritated and slightly swollen. This additional tissue bulk reduces the space in the airway further, compounding the snoring. For people who find their snoring is worst in winter or in dry environments, this drying effect is frequently a contributing factor.
Why People Breathe Through Their Mouths During Sleep
Is snoring caused by mouth breathing, or does the underlying cause run deeper? In most cases, mouth breathing is itself a symptom of something preventing comfortable nasal breathing.
Nasal Congestion
Allergies, colds, sinusitis, and rhinitis all cause nasal congestion that forces a switch to mouth breathing. This is often why snoring worsens during certain seasons or when someone has a respiratory infection. Even mild, chronic nasal congestion that does not feel significant during the day can be enough to cause mouth breathing during sleep.
Nasal Anatomy
Structural features of the nose can obstruct airflow even when no infection or allergy is present. A deviated nasal septum, nasal polyps, or enlarged turbinates reduce the airway enough to make nasal breathing difficult during sleep. These are anatomical factors rather than lifestyle ones, and they may require specific investigation and treatment.
Enlarged Tonsils or Adenoids
In children in particular, enlarged tonsils and adenoids can partially block the nasal airway, creating a habitual pattern of mouth breathing that persists even after the tissues reduce in size. Adults can also experience tonsillar enlargement, and this should be investigated where suspected.
Habitual Mouth Breathing
Some people develop a pattern of mouth breathing even when nasal airflow is unobstructed. The jaw muscles and breathing patterns during sleep can adapt over time, making mouth breathing feel normal even when the nose is clear. Myofunctional therapy, exercises that retrain tongue position and breathing patterns, can be effective in these cases.
Is Snoring Mouth Breathing Exclusively?
Is snoring mouth breathing in all cases? Not always. Nasal snoring does occur, particularly when congestion forces air through a narrow nasal passage at high velocity. However, mouth breathing snoring tends to be louder and more disruptive, because the tongue and soft palate play a much more active role in generating vibration when the mouth is open.
For people who snore with their mouths closed, the cause is more likely to lie within the nasal cavity itself, or be related to soft palate anatomy. An assessment with a specialist is the most reliable way to identify where snoring originates and which approach will be most effective.
How to Stop Mouth Breathing and Snoring
How to stop mouth breathing snoring depends on identifying and addressing the underlying cause. There is no universal solution, but several approaches are effective depending on the individual.
Address Nasal Obstruction
If nasal congestion is the root cause, treating it will often reduce or resolve mouth breathing and the snoring it produces. This might mean managing seasonal allergies with antihistamines or nasal corticosteroids, treating chronic sinusitis, or investigating whether structural factors such as a deviated septum are contributing.
Oral Appliance Therapy
A mandibular advancement device (MAD) is one of the most effective treatments for snoring associated with mouth breathing. The device holds the lower jaw slightly forward during sleep, keeping the tongue from dropping back and maintaining a more open airway. This reduces the vibration that causes snoring and can also discourage mouth breathing by changing the position of the jaw and soft tissues during sleep.
A mandibular advancement device for snoring is custom-fitted to the individual’s teeth and is significantly more effective and comfortable than over-the-counter alternatives.
Positional Adjustments
Sleeping on your back increases the likelihood of the jaw dropping open and the tongue falling back. Switching to a side-sleeping position reduces this tendency and often produces a noticeable reduction in snoring. Slightly elevating the head of the bed can also make nasal breathing easier and reduce snoring frequency.
Treating Sleep Apnoea When Present
Mouth breathing snoring is sometimes a sign of obstructive sleep apnoea, a condition where the airway repeatedly collapses during sleep. Snoring associated with sleep apnoea tends to be accompanied by gasping, choking, or observed pauses in breathing. If these signs are present, a full specialist assessment is essential, as sleep apnoea carries significant cardiovascular and metabolic consequences. The wider health effects of chronic snoring are a further reason not to leave persistent snoring unaddressed.
Frequently Asked Questions
Is snoring mouth breathing?
Not always, but mouth breathing is one of the most common causes of snoring. When the mouth falls open during sleep, the tongue and soft palate drop back and narrow the airway, producing the vibration that causes snoring. Snoring can also occur during nasal breathing, though this is less common and typically less disruptive.
Does mouth breathing cause snoring?
Yes. Mouth breathing changes the position of the tongue and soft palate in a way that narrows the upper airway and creates tissue vibration. Addressing the underlying reason for mouth breathing, whether that is nasal congestion, anatomy, or habitual breathing patterns, will often reduce or resolve snoring.
What causes mouth breathing during sleep?
The most common causes are nasal congestion from allergies or infection, anatomical factors such as a deviated septum or enlarged tonsils, and habitual breathing patterns. Even mild, chronic nasal obstruction that is barely noticeable during the day can be enough to cause mouth breathing during sleep.
How do I stop mouth breathing and snoring?
The right approach depends on the underlying cause. Treating nasal congestion, addressing structural issues in the nose, using a custom mandibular advancement device, and adjusting sleep position are all options depending on the individual situation. A specialist assessment is the most direct way to identify the cause and recommend appropriate treatment.
Can a mandibular advancement device help with mouth breathing snoring?
Yes. A custom-fitted mandibular advancement device repositions the lower jaw during sleep to maintain an open airway and reduce the tendency for the mouth to fall open. It is one of the most effective and well-tolerated treatments available for snoring related to mouth breathing.
Take the Next Step
If mouth breathing and snoring are affecting your sleep or your partner’s, a specialist assessment is the most direct route to a solution. As a dental sleep medicine specialist in London, Dr. Aditi Desai offers comprehensive evaluations and personalised treatment, including custom oral appliance therapy, at her practices on Wimpole Street, The Shard, and Cromwell Hospital.
Book a consultation to discuss your symptoms and find the right approach for you.
