Why Would a Child's Breath Smell Bad?

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When your child has bad breath, it isn't something to ignore. While it may be nothing to worry about, bad breath can be brought on by many different causes, including serious medical conditions. 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.

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

Eating certain foods increases the likelihood of your child exhibiting bad breath. 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.

Nasal Issues

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

Dry Mouth

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.


Bad breath can be caused by diseases not located in the mouth. Other conditions that may be causing your child to have bad breath include diabetes, failure of the liver or kidneys or chronic bronchitis. 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.