Reviewed on 3/10/2010
I discussed your question with my colleague, Sandy Newmark, M.D., a California-based pediatrician on the faculty of the Arizona Center for Integrative Medicine. He tells me that bad breath in a child as young as two is unusual and should be investigated. You might take your son to a pediatric dentist first to make sure that tooth decay isn't the problem. A child's teeth are subject to decay as soon as they appear, as early as six months of age. Youngsters should see a dentist for the first time by their first birthday to make sure that no decay is present from a bottle or from nursing.
If your son's teeth aren't the cause of his bad breath, a number of other health problems could be to blame. These include chronic throat or sinus problems, or obstruction from large tonsils or adenoids. Bad breath is sometimes a symptom of a chronic sinus infection, which can be difficult to diagnose in young children. They so often have colds that respiratory symptoms due to sinus infections may be mistaken for the latest bug that's circulating among the toddler set. Your pediatrician should be able to sort through the various possibilities.
If no dental or medical cause turns up, Dr. Newmark suggests eliminating food groups one at a time to see if this makes a difference. The idea is to identify foods to which a child has a specific hypersensitivity or intolerance. Consider the following questions: What foods does the child frequently eat? Are there any cravings or foods that make him feel better? What foods would be difficult to give up or go without? The most common approach is to eliminate all or some of the most common ones that cause reactions in kids: eggs; milk and other dairy products; wheat and other gluten-containing grains; citrus; peanuts; and shellfish. Eliminate each category of foods for two to four weeks and then add them back one at a time to track which ones elicit symptoms. Keeping a food diary is the best way to do this.
Andrew Weil, M.D.