We usually associate bad breath, or halitosis, with adult breath, but bad breath in children certainly does occur. Perhaps it is less common because some of the conditions that favor the growth of anaerobic bacteria - the bacteria that produce foul smelling volatile sulfur compounds (VSC) - are uncommon in children. These bacteria can be present in children's mouths as well, however, and they can cause bad breath.

Sweet smelling bad breath in children, however, can be a sign of something more serious. Bad breath in children that has more of a sugary or fruity odor, rather than a rotten egg smell, is a symptom of ketoacidosis, a serious complication in diabetes. Ketoacidosis can be deadly, so if you notice a sweet smell on your child's breath, and the child seems at all unwell, a prompt visit to the doctor is in order. If the smell is very transient and the child has no other symptoms, the sweet smell may have been caused by a recently eaten food and is probably nothing to worry about.

Frequent bad breath in children, the rotten egg kind as opposed to sweet smelling bad breath in children, is probably caused by the same oral bacteria that cause halitosis in adults. In children, these bacteria are unlikely to be multiplying in airless pockets formed by gum disease, and are probably living almost exclusively on the surface of the tongue, nestled down between the taste buds and protected by a layer of other bacteria and non-living material. This is called a biofilm - a mixed community of organisms functioning together. It's not necessarily a bad thing, but it's unfortunate when the bacteria that produce VSC are a big part of the mix. They cause bad breath in children.

Frequent bad breath in children will respond best to efforts to reduce the number of anaerobic VSC-producing bacteria on the tongue. Gentle brushing of the tongue will remove many of them mechanically. Care should be taken not to be too enthusiastic however: too vigorous scraping or brushing of the tongue can do damage. Many over the counter remedies, and natural remedies are available; be sure to check whether your choice is recommended for bad breath in children. And remember, sweet smelling bad breath in children can be a sign of serious illness: don't try to treat this at home.