A search of the medical literature yields some interesting facts about bad breath. It is also called fetor ex ore, fetor oris, halitosis, and oral malodor. It is one of the most common medical problems in humans; however, a lack of epidemiological data make it impossible to accurately state how common it really is. It has both medical and social significance, since sufferers also experience social problems. It has a variety of underlying causes, including both serious organic disease, and mental delusion.
Explaining malodor then, is achieved on a case by case basis. Fortunately, though this condition wasn't taken seriously by the medical profession until relatively recently, it is now getting careful and widespread attention, and sufferers can get help. One of the undisputed facts about bad breath is that in most cases, the underlying cause is located in the mouth, and this is the best place to start. Surprisingly, the first step is to confirm that a genuine case of halitosis exists.
Because halitosis carries a social stigma, and because scientifically valid facts about bad breath are not widely known, almost everyone fears that they have it, and a significant number are convinced that they have it when they actually do not. (We are not very good judges of our own breath odor.) Specialists have devised several tests to objectively measure the degree of odor present, and can help such people by explaining oral malodor and offering assurances that there isn't actually a problem.
At the other end of the spectrum are those who have halitosis because they suffer from undiagnosed underlying disease. Because of these rare cases, it's important that people familiarize themselves with the facts about bad breath and see a specialist if they think they have it, or when other people remark that their breath smells bad or even strange. Thus, though explaining oral malodor in most instances is a simple case of confirming that it originates in the mouth, in the most extreme cases, it could save a life.