Baby Breath Smells Like Fish

Baby Breath Smells Like Fish


Your baby’s coos and giggles are music to your ears until you catch a whiff of something fishy. You lean in closer, and there it is: your baby’s breath smells fishy. But why? As a caring parent, this can be quite alarming. But before you panic, it’s essential to understand that bad breath in babies is not uncommon and can be caused by several factors.

Understanding Why Baby’s Breath Stinks


Causes of Baby’s Bad Breath


Inadequate Oral Hygiene

Although most babies don’t have many teeth to brush, oral hygiene is still crucial. Bacteria can build up on the baby’s gums, tongue, and any existing teeth, leading to bad breath. Milk residues, food particles, and other substances can also contribute to the problem if not cleaned properly.

Mouth Breathing = Dry Mouth

A dry mouth often leads to bad breath. Babies who breathe through their mouths may have less saliva flow, which is essential for washing away odor-causing bacteria.

Sinus Infections

Sinus infections or a persistently runny nose can also cause a baby’s breath to smell fishy. The bacteria from the nasal passages can end up in the baby’s mouth, leading to bad breath.

Acid Reflux

Acid reflux can also contribute to a baby’s foul breath. The condition brings up stomach acid into the throat and mouth, creating a distinct and unpleasant odor.

Tooth Decay

Yes, even babies can get tooth decay! When a tooth appears, it needs to be cared for. Tooth decay can create a foul smell in the child’s mouth.

Foreign Objects in the Mouth

Ever found your baby’s hands in their mouth or them sucking on a toy? Babies are curious and often put foreign objects in their mouths. If something gets stuck, it can create bad breath.

Health Conditions Health Conditions that Can Lead to Baby’s Bad Breath

Sometimes, persistent bad breath in babies can indicate underlying health issues. It’s essential to be aware of these possibilities and consult a healthcare provider if you suspect any of these conditions.

Oral Thrush

Oral thrush is a type of yeast infection that can occur in the baby’s mouth, leading to a distinctive unpleasant smell. It appears as white patches on the tongue, inside the cheeks, and on the roof of the mouth.

Respiratory Infections

Respiratory infections like colds, sinus infection, or bronchitis can cause bad breath in babies. Bacteria or viruses that cause these infections can produce odorous compounds that result in bad breath.

Gastroesophageal Reflux Disease (GERD)

GERD, or acid reflux, is a condition where stomach acid backs up into the esophagus. In babies, this can cause bad breath, especially if the refluxed material is being swallowed or spit out.


While rare in babies, uncontrolled diabetes can lead to a unique breath odor often described as fruity or like rotten apples due to the production of ketones.

Tonsillitis or Adenoiditis

Inflammation or infection of the tonsils or adenoids can cause bad breath. These conditions can trap bacteria in the mouth and throat, leading to bad breath.

Foreign Bodies in the Nose

Babies are curious and may stick small items up their noses. A foreign object lodged in a nasal passage can cause a baby bad breath.

Remember, if baby bad breath persists despite maintaining good oral hygiene, or if it’s accompanied by other symptoms, it’s important to consult a healthcare provider. Timely diagnosis and treatment of these conditions can help resolve bad breath and prevent complications.

Oral Health Tips for Child’s Bad Breath

Ensuring Proper Oral Care Routine

An essential step to preventing baby bad breath is establishing a good oral care routine. Even before the first tooth appears, wipe your baby’s gums with a soft, damp cloth after feedings. As they grow older and teeth start to appear, brushing becomes crucial.

Oral Care Products for Babies

When your baby’s first tooth appears, it’s time to start using infant toothpaste. These kinds of toothpaste are gentle on baby’s gums and safe if swallowed in small amounts. They can help keep your baby’s mouth clean and free from bacteria that cause bad breath.

Soft-Bristled Toothbrush

A soft-bristled toothbrush is best for your baby’s delicate gums and emerging teeth. It’s gentle yet effective at cleaning food particles that can create bad breath.

Fluoride Toothpaste

When your child is old enough to spit out toothpaste (usually around age 3), you can start using a pea-sized amount of fluoride toothpaste. Fluoride can help prevent tooth decay, a potential cause of bad breath.

Good Feeding Habits

Ensure your child isn’t going to bed with a bottle as it can lead to tooth decay. Additionally, discourage your baby from thumb-sucking or prolonged use of a pacifier, as these habits can impact teeth development and lead to bad breath.

Managing Dry Mouth in Babies

Dry mouth, or xerostomia, is not a common condition in babies, but it can happen under certain circumstances, such as dehydration or certain health conditions. Saliva flow is important because it aids digestion, cleanses the mouth, and helps prevent infection by controlling bacteria. Therefore, managing dry mouth is essential for preventing bad breath and maintaining oral health.

Ensure Adequate Hydration

One of the main causes of dry mouth in babies is dehydration. Make sure your baby is getting enough fluids, whether it’s through breast milk, formula, or, for older babies, water.

Humidify Your Baby’s Room

Dry air can contribute to a dry mouth. Using a humidifier in your baby’s room can help maintain moisture in the air and prevent the mouth from drying out, especially during sleep.

Regular Mouth Cleaning

Regular mouth cleaning is important to prevent bacteria buildup, which can worsen with dry mouth. You can use a soft, damp cloth to gently clean your baby’s gums.

Saliva Substitutes

In some cases, your healthcare provider might recommend a saliva substitute or oral gel designed for infants to help moisturize the mouth.

Checking Medications

Some medications can cause dry mouth as a side effect. If your baby is on any medication, discuss with the pediatrician if it could be causing dry mouth and what can be done about it.

Regular Pediatric Check-ups

Regular check-ups allow your pediatrician to monitor your baby’s overall health and catch any potential issues early, including signs of dry mouth.

In conclusion, if you suspect your baby has a dry mouth, it’s important to address the issue promptly to ensure their comfort and maintain their oral health. Persistent dry mouth or associated symptoms like bad breath should be discussed with a healthcare provider.

Dietary Factors and Baby’s Breath

Your baby’s diet can also influence the smell of their breath. Different types of foods, milk or formula, and even certain medications can affect the smell.

Breastfeeding and Baby’s Breath

Breastfeeding is often associated with sweeter-smelling breath in babies due to the natural sugars in breast milk. However, any milk residue left in the mouth can still lead to bad breath if not cleaned properly.

Formula Feeding and Baby’s Breath

Babies who are formula-fed might have a different breath odor compared to breastfed babies. Some parents notice a slight metallic smell or a smell that is less sweet than the breath of breastfed babies.

Role of Probiotics in Oral Health

Emerging research suggests that probiotics can play a role in oral health and help combat bad breath. Probiotics are beneficial bacteria that can help balance the oral microbiome.

Probiotics and Baby’s Breath

While most studies on probiotics and oral health have been done on adults, some evidence suggests they might also help improve a baby’s breath. Probiotic-rich foods, such as certain types of yogurt, are safe for babies to consume and might help combat bad breath. However, more research is needed in this area.

Keeping Baby’s Items Clean

Lastly, keeping the baby’s items clean can also contribute to preventing bad breath.

Cleaning Baby’s Toys

Babies often put toys in their mouths. If these toys aren’t clean, they can introduce bacteria into the baby’s mouth, leading to bad breath.

Cleaning Feeding Items

Regularly cleaning bottles, pacifiers, and any feeding items can also help prevent the growth of bacteria that can cause bad breath.

When to Seek Medical Help

If your child’s bad breath persists despite your best efforts, it may be time to consult a healthcare provider. Persistent or severe bad breath can be a sign of underlying health conditions.

Recognizing Other Symptoms

Accompanying symptoms like persistent fever, trouble swallowing, or a significant loss of appetite may suggest a more severe condition. In such cases, don’t hesitate to seek professional help.

Visit to Pediatric Dentist

Regular check-ups with a pediatric dentist are crucial for maintaining your child’s oral health. If your child’s breath smells fishy consistently, discuss it during your next appointment. The dentist can help identify any potential issues like gum disease or tonsil stones that may be contributing to the problem.


In conclusion, a baby’s breath smelling like fish can be concerning, but it’s often manageable with good oral care and hygiene. Always monitor your baby’s oral health and seek medical advice when necessary. Remember, prevention is always better than cure, especially when it comes to your child’s health.



  1. Why does my baby’s breath smell like fish? There are several potential reasons, including inadequate oral hygiene, mouth breathing, sinus infections, acid reflux, tooth decay, or a foreign object in the mouth.
  2. How can I improve my baby’s bad breath? Start with good oral hygiene habits. Clean your baby’s mouth regularly, even before the first tooth appears. As they grow older, introduce appropriate toothbrushing habits.
  3. When should I be concerned about my baby’s bad breath? If the bad breath persists despite good oral hygiene practices, or if it comes with other symptoms like fever or loss of appetite, you should seek medical advice.
  4. Can I use regular toothpaste for my baby? Infant toothpaste should be used for babies as it’s safe to swallow. When your child is old enough to spit out toothpaste, usually around age 3, you can start using a pea-sized amount of fluoride toothpaste.
  5. How often should I clean my baby’s mouth? It’s a good practice to clean your baby’s mouth after feedings and before bedtime.


This post is written and edited by Sandy who is a clinical pharmacist with over 20 years of experience specializing in pre-natal and post-natal care.