Can mouth breathing affect a child's school performance?

Short answer: It can. Children who mouth-breathe or snore because of enlarged adenoids, tonsils or nasal allergy often sleep poorly. This may show up as daytime tiredness, irritability, restlessness and poor attention in class. If your child snores most nights or sleeps with the mouth open, mention it to your paediatrician or an ENT.

Key takeaways

• Children are designed to breathe through the nose, especially during sleep.
• Enlarged adenoids, tonsils and allergy are common reasons for mouth-breathing in children.
• Broken sleep in children may look like hyperactivity or poor attention rather than sleepiness.
• Many causes can be treated, so persistent snoring deserves a check-up.

Dr. Prashanth's perspective

The signs of mouth breathing I look for in children are a high-arched palate, drooling of saliva, a stuffy nose, reduced hearing, poor attention and bed-wetting. Parents also tell me about poor appetite, poor growth and falling grades at school.

— Dr. Prashanth R. Reddy, ENT Surgeon, ENTHealth360

Why do some children breathe through the mouth?

Children usually mouth-breathe because something is blocking easy airflow through the nose.

The most common causes are enlarged adenoids (a pad of tissue at the back of the nose), large tonsils and nasal allergy. Frequent colds, a deviated septum or habits that continue after a blockage settles can also play a part.

During sleep, the airway muscles relax. If the nose or throat is already narrow, a child may snore, breathe noisily or, in some cases, have brief pauses in breathing. This is called sleep-disordered breathing, and at the more serious end it includes obstructive sleep apnea.

How can mouth breathing show up at school?

In children, poor sleep often looks different from poor sleep in adults. Rather than appearing sleepy, many children become restless or irritable.

• Difficulty paying attention or finishing tasks.
• Hyperactive or fidgety behaviour.
• Irritability, mood swings or frequent tantrums.
• Forgetfulness and slower learning.
• Tiredness, especially in the morning.

At home, you may notice snoring, an open mouth during sleep, restless sleep, sweating at night, bedwetting that returns after being dry, dark circles under the eyes, or a dry mouth and bad breath in the morning. Long-standing mouth-breathing may also be linked with changes in how the face and teeth develop, which a dentist or orthodontist may notice.

What can parents do at home?

Some simple steps may help while you arrange a check-up.

• Watch and listen to your child sleep for a few nights. A short audio or video recording can help the doctor, if your child is comfortable with it.
• Keep the bedroom clean, dust-free and well ventilated. Wash bedding regularly in hot water.
• Avoid smoking anywhere near your child.
• Use saline nasal drops or sprays for mild congestion, as advised by your doctor.
• Keep a regular bedtime and limit screens in the hour before sleep.
• Encourage outdoor play and a balanced diet.

In Bangalore, pollen, dust, construction and traffic pollution can trigger nasal allergy in many children, especially when seasons change and during the monsoon.

How are breathing, sleep and energy connected in children?

Easy nose breathing at night supports the deep sleep children need for growth, mood and learning.

Deep sleep is when much of growth hormone is released and when the brain consolidates what was learned during the day. When breathing is disturbed, sleep may be broken many times through the night, even if the child does not fully wake.

The result can be a child who spends enough hours in bed but wakes unrefreshed. For many children, treating the cause of mouth-breathing can support better sleep, steadier energy and improved behaviour and attention, though every child is different.

How does nose breathing support energy and BMR?

Your basal metabolic rate (BMR) is the energy your body burns at rest to keep the heart beating, the brain working and cells repairing. Your cells make that energy using oxygen, so how well you breathe matters.

Nose breathing helps in two ways:

• Warm, moist, filtered air. The nose warms, humidifies and filters each breath before it reaches the lungs. Conditioned air is gentler on the airway lining, which matters in Bangalore's air-conditioned offices and traffic dust. Mouth breathing skips this step and can leave the throat and airways dry.
• Nitric oxide from the sinuses. The paranasal sinuses continuously make nitric oxide (NO), a natural gas. When you breathe in through your nose, small amounts of this NO travel to the lungs, where studies suggest it may help widen tiny blood vessels and improve oxygen uptake. Mouth breathing largely bypasses it.

Nose breathing does not "boost" your BMR. That is set mainly by muscle mass, age, body size and hormones such as thyroid. But comfortable nasal breathing by day, and undisturbed breathing at night, support efficient oxygen supply and deeper sleep, which your body needs to use energy well and recover.

A simple check: sit quietly and breathe through your nose with your mouth closed for two minutes. If that feels difficult, or one side is always blocked, it is worth having your nose examined.

When should you see an ENT?

See your paediatrician or an ENT if your child shows signs of disturbed breathing during sleep.

• Snoring on most nights, lasting more than a few weeks.
• Sleeping with the mouth open most of the time.
• Restless sleep, bedwetting that returns, or night sweats.
• Frequent throat infections or ear infections.
• Seek prompt medical care if you notice pauses in breathing, gasping or choking during sleep.
• Seek urgent care if your child has difficulty breathing while awake, bluish lips, or cannot swallow fluids.

How an ENT evaluates and treats it

An ENT checks the nose, adenoids, tonsils and ears to understand why a child is mouth-breathing.

The visit includes a history of sleep and symptoms and an examination of the nose and throat. A gentle nasal endoscopy or an X-ray may be used to assess the adenoids. A hearing test may be done if there are ear problems. If sleep apnea is suspected, a sleep study may be advised.

Treatment depends on the cause. Allergy management and nasal sprays help many children. In selected cases, removal of the adenoids and/or tonsils may be considered. The right option depends on the cause and the child's overall health.

Frequently asked questions

Does nose breathing give me more energy? It does not add energy by itself, but it delivers warm, humidified air and sinus nitric oxide to the lungs, which may help oxygen uptake. Together with better sleep, that supports the energy your body uses at rest (BMR) and during activity.

Is snoring normal in children? Occasional snoring during a cold is common. Snoring on most nights is not normal and is worth discussing with your paediatrician or an ENT.

Will my child outgrow mouth breathing? Adenoids often shrink with age, but the effects of months or years of poor sleep can matter in the meantime. A check-up helps decide whether waiting or treatment is more suitable.

Can mouth breathing be mistaken for ADHD? Some children with disturbed sleep show inattention and hyperactivity. Doctors often check sleep and breathing as part of assessing attention problems.

References

• Lundberg JO, Farkas-Szallasi T, Weitzberg E, et al. High nitric oxide production in human paranasal sinuses. Nature Medicine. 1995;1(4):370-373.
• Lundberg JO, Settergren G, Gelinder S, et al. Inhalation of nasally derived nitric oxide modulates pulmonary function in humans. Acta Physiologica Scandinavica. 1996;158(4):343-347.
• Keck T, Leiacker R, Heinrich A, Kühnemann S, Rettinger G. Humidity and temperature profile in the nasal cavity. Rhinology. 2000;38(4):167-171.

About the author

Dr. Prashanth R Reddy is an ENT surgeon at ENTHealth360, Bangalore (MS ENT; MBA, IIM Bangalore; Seoul Rhinoplasty Fellowship), seeing patients at Sakra World Hospital, Marathahalli and in Koramangala. His practice focuses on how breathing affects sleep, energy and everyday performance.

Related reading: Why am I always tired even after 8 hours of sleep? · Why do I wake up tired every morning?

For educational purposes only. Not a substitute for medical advice. Please consult a qualified ENT specialist.