Bad breath, or halitosis, is an oral health condition where the main symptom is unpleasant-smelling breath. Common causes of halitosis in children include dental cavities, a lack of oral hygiene, mouth breathing, and respiratory conditions, such as sinusitis.

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Children can have bad breath for many reasons. It is usually temporary and resolves after brushing their teeth. If halitosis persists, it may be due to a lack of oral hygiene or other causes.

A pediatric dentist can help identify the cause and advise on the next steps. This may include treatment or further investigation.

Maintaining good oral hygiene, such as cleaning the mouth regularly, can help prevent halitosis in children.

This article discusses the causes of halitosis in children. It also looks at how a parent or caregiver can treat and prevent it, and when to consult a healthcare professional.

The National Institute of Diabetes and Digestive and Kidney Diseases notes that GER in infants can lead to regurgitation and “spitting up.”

GER and regurgitation are common in infants, particularly those under the age of 1 year.

Experts theorize that several factors can cause GER in infants. For the first 6 months of their life, an infant spends a lot of time lying down and consuming meals that mainly consist of liquids.

GER occurs less often as the infant stands up more and eats more solid foods. It also improves as their digestive system develops.

Halitosis in children can occur as a result of the food that they have eaten.

For example, vegetables such as garlic and onion can lead to bad breath. After digestion, odorous molecules enter the bloodstream and can exit through the lungs and breathing.

Fish, cheese, meat, and other high protein foods can worsen bad breath.

Hard and dry foods, such as chocolate, toffee, and potato chips, can become trapped in the teeth, resulting in the growth of bacteria.

A 2021 comprehensive review notes that a lack of oral hygiene can lead to halitosis.

Brushing the teeth incorrectly can lead to leftover food particles in the mouth. This can result in the development of bacteria, causing bad breath.

A lack of oral hygiene can increase the child’s risk of dental conditions, such as dental cavities and gum disease.

The National Institute of Dental and Craniofacial Research notes that saliva helps clean the mouth. Saliva washes away food debris, which can neutralize oral bacteria and cavity-causing acids that are present in the mouth.

Children with dry mouths are at higher risk of halitosis and tooth decay since food particles and cavity-causing bacteria stay for longer periods of time in the mouth.

Dehydration, mouth breathing, hot weather, certain medications, or an underlying health condition can cause dry mouth in children.

Research from 2015 suggests that children who breathe with their mouths appear to have halitosis. This may be due to the drying of saliva in the mouth. Mouth breathing causes a dry mouth, which can lead to bad breath.

Children may breathe through their mouth due to nasal congestion or personal habit. Mouth breathing due to nasal congestion should disappear once the congestion clears up.

If a parent or caregiver observes that their child is breathing through their mouth, they should contact a pediatrician.

A pediatrician can help rule out any condition obstructing the airways and prescribe medications. They may also offer advice on encouraging children to breathe through their noses. One method involves humming with their tongue placed on their palate.

If a person discovers that the child has a runny nose accompanied by halitosis, it may be due to a foreign object in the nose.

Research from 2017 indicates that an impacted foreign body in the nose can cause bad breath in children.

As a result of curiosity, children may insert foreign objects, such as beads, legos, tiny batteries, bits of food into their noses. This can lead to an infection and cause halitosis.

In this situation, a person should not try to remove the foreign object forcefully — they should visit a pediatrician to remove it.

According to health experts, halitosis may be due to underlying health conditions. These include:


According to a 2015 study, sinusitis may cause bad breath in children.

Sinusitis is a condition that occurs due to the inflammation of the cavities around the nasal passages. This inflammation may be due to viruses, bacteria, fungi, or allergies.

Sinus infections collect fluids in the nasal passages and throat, making it ideal for bacteria to thrive.


Tonsillitis is an infection that makes the tonsils appear red and swollen. It occurs due to viruses or bacteria. Tonsilitis most commonly occurs in those over 2 years old.

Enlarged tonsils can cause halitosis when they trap nasal secretions, food particles, and bacteria.


If a person notices that the child has swollen gums and halitosis, they may have gingivitis.

Gingivitis is an inflammation of the gums that occurs due to a buildup of bacterial plaque around the gum line. The bacteria around the plaque produce toxins resulting in swollen and irritated gums and bad breath.

A lack of oral hygiene or an underlying health condition can increase a child’s risk of gingivitis.

Tooth decay and other dental infections

According to a 2021 study, children with tooth decay are more likely to have halitosis.

As well as food getting stuck in the damaged portion of the tooth, cavity-causing bacteria can also emit unpleasant odors.

Other dental infections, such as dental abscesses or mouth sores, may also cause halitosis in children.

Treatment for halitosis in children depends on the cause. If a person is concerned, they should contact a doctor or dentist to ensure that the cause is not an underlying health condition.

A healthcare professional will be able to advise on the correct treatment options if a medical condition is causing halitosis.

To get rid of halitosis in children at home, caregivers should:

  • Help babies and children clean their gums and teeth twice daily.
  • Teach children to practice good oral hygiene.
  • Feed them a healthy balanced diet.
  • Encourage limited consumption of sugary foods and drinks.
  • Give them plenty of water to drink to keep their mouth moist.
  • Keep up with their dental appointments.

Good oral hygiene can help to prevent halitosis in children.

For babies

For infants, good oral hygiene starts before their first tooth appears.

According to the Centers for Disease Control and Prevention (CDC), parents and caregivers can start by cleaning the infant’s gum twice daily with a soft clean cloth and water — in the morning after the first feeding and before bed.

In addition, the American Dental Association (ADA) recommends taking the infant to their first dental checkup soon after the first tooth appears and no later than their first birthday.

The first dental appointment is an opportunity for caregivers to learn how to care for their child’s teeth and avoid oral health conditions, such as halitosis.

After the first appointment, the American Academy of Pediatric Dentistry (AAPD) recommends taking children to regular checkups every 6 months.

For children

Experts recommend that caregivers help children brush their teeth twice daily using a soft-bristled toothbrush and toothpaste containing fluoride.

The ADA notes that a caregiver should use a tiny amount of toothpaste, approximately the size of a grain of rice, for those under 3 years.

For those older than 3, a caregiver can use a larger amount of toothpaste, similar to the size of a pea.

Children should also drink tap water that contains fluoride. Caregivers of children who drink water from a well should talk with a pediatrician or dentist about the potential need for fluoride supplements.

For those under the age of 6, parents and caregivers should observe them brush their teeth and ensure that the child spits out the toothpaste.

A person should contact a doctor if they notice that the child has any of the following symptoms:

  • persistent halitosis
  • dry mouth
  • dental abscess
  • dental cavities
  • sore throat
  • difficulty eating, drinking or swallowing
  • frequent spitting and vomiting
  • high temperature
  • red, tender, or swollen gums
  • swollen tonsils
  • sores on the gums or mouth
  • thick, colored drainage in the nose

Children can have halitosis for several reasons. This may be due to poor oral hygiene, an underlying health condition, or other causes.

Practicing good dental hygiene and attending dental appointments can help prevent and treat halitosis in children.

A pediatric dentist may prescribe medications, offer lifestyle changes, or further investigate.