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Why Would a Child's Breath Smell Bad?

When your child has bad breath, it isn't something to ignore 34. While it may be nothing to worry about, bad breath can be brought on by many different causes, including serious medical conditions 34. By determining the cause of your child’s bad breath, you can remedy the immediate problem and any underlying condition that may be causing the bad breath 34.

Dental Hygiene

When pieces of food remain in your child’s mouth for a prolonged period, they attract bacteria that can put off a foul odor. Not brushing and flossing regularly can also lead to plaque build-up on teeth, and if your child goes a prolonged period without cleaning his teeth, the spaces between his teeth and gums can house more plaque and cause his breath to grow even worse.

Dietary Culprits

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Eating certain foods increases the likelihood of your child exhibiting bad breath 34. A few common culprits include onions, garlic and certain vegetables such as broccoli. Your child will be stuck with food-induced bad breath until all of the food is eliminated from her body, via breathing, sweating and using the restroom 34.

Nasal Issues

Health issues varying from sinus and respiratory infections to cleft palate and tonsil stones can result in bad breath 34. A child may also experience nasal-related bad breath when he sticks something in his nostril that doesn’t belong there 34. If left undetected, a penny or pea stuffed up the nose can attract bacteria that cause bad breath 34.

Dry Mouth

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Without sufficient saliva, your child can’t rinse out all of those odor-causing foods and bacteria. Because a child with dry mouth doesn’t make sufficient saliva, this condition increases her risk for bad breath 34.


Bad breath can be caused by diseases not located in the mouth 34. Other conditions that may be causing your child to have bad breath include diabetes, failure of the liver or kidneys or chronic bronchitis 34. In the event these conditions are causing your child’s bad breath, treating these conditions is the only way for your child to find relief 34.