Bad breath: Causes and risk factors.

In most cases bad breath (halitosis) is caused by the presence of oral bacteria. There can be, however, other factors that influence the odor associated with one's breath and, in fact, the quality of a person's breath will ultimately depend on a number of different variables.

The next portion of our discussion details some of these specific risk factors and conditions. When reading this information you should take notice of the fact that many of the items we list directly relate to:

Oral bacteria. Conditions which promote the growth of oral bacteria. Not cleaning, or not being able to clean, those areas where oral bacteria reside.

Later on our pages will describe in greater detail how bacteria cause mouth odors and outline methods for cleaning these bacteria away. Right now however, at this point in our discussion, just realize that anything that promotes the growth of oral bacterial will most likely heighten a person's problems with bad breath too.

How do foods cause bad breath?

Everyone knows that certain foods have a reputation for causing bad breath. Two of the most notorious ones are garlic and onions.

When we eat our digestive system breaks the food we have consumed down in to its component molecules, some of which have very unpleasant and characteristic odors. As these molecules are created they are absorbed into our circulatory system so they can subsequently be distributed throughout the remainder of our body as nourishment.

As our blood travels through our lungs some of these molecules will be released into them. As a result, as we exhale our breath will contain some of these offending molecules, thus producing breath malodor.

While this type of bad breath can be annoying or embarrassing, this is not the type of breath problem we discuss on the subsequent pages of this topic. Bad breath caused by the consumption of certain foods will resolve on its own in a day or so as your body completes the process of breaking down and utilizing, or else excreting, the offending molecules. You can control this type of breath problem simply by avoiding or minimizing your consumption of these foods.

Why is smoking a risk factor for halitosis?

You are probably familiar with people who have "smoker's breath." While even though the precise odor associated with smoking depends on a number of factors, a great part of it is directly related to the tar, nicotine, and other foul smelling substances derived from tobacco's smoke that accumulates on a person's teeth and oral soft tissues (tongue, cheeks, gums,...).

Once again, while this type of breath malodor can be a problem, this is not the precise type of bad breath we address on the pages of this topic. Short of quitting smoking there is no effective way to totally eliminate smoker's breath, although immaculate oral hygiene can help to minimize it.

As a contributing risk factor, the act of smoking does have a drying effect on oral tissues. Decreased moisture in the mouth limits the washing and buffering effect of saliva on oral bacteria and their waste products, thus aggravating a person's problems with bad breath. More information about breath problems associated with dry mouth conditions is discussed just below.

It is also known that people who smoke are at greater risk for having problems with periodontal disease ("gum disease") than people who do not smoke. Gum disease, as it relates to bad breath, is discussed in more detail below.

Why is having a dry mouth (xerostomia) a risk factor for bad breath?

Even if you don't have much of a problem with bad breath you have probably noticed that your breath is least pleasant in the morning when you first wake up. This is because during the night a person's mouth dries up somewhat, due to the human body's natural tendency to reduce salivary flow when a person sleeps. This same souring effect is sometimes noticed by teachers, lawyers, and anyone else whose mouth has become dry after having to speak for a prolonged period of time. Additionally, people who breathe through their mouth, are fasting, or else are under stress can find that they have comparatively dry mouths and therefore persistent problems with breath odors.

One explanation for this phenomenon is that the moisture found in our mouth helps to cleanse it. The presence of oral fluids encourages us to swallow. With each swallow we take we wash away bacteria, as well as the food and debris on which they feed. This same moisture also dilutes and washes away the waste products that oral bacteria produce.

Additionally, saliva is a very special form of mouth moisture. It's the body's natural mouth rinse. Beyond the washing and diluting effect that any oral moisture can provide, saliva has the added benefit that it contains compounds that can kill bacteria and buffer their waste products. So, when our mouth becomes dry, all of the benefits provided by each source of oral moisture are minimized. The net result is that the conditions for bacterial growth are enhanced while the neutralization of bacterial waste products is reduced.

Some people have chronically dry mouths. This condition is termed "xerostomia." Xerostomia can be a side effect of the medication a person is taking. Antihistamines (allergy and cold medications), antidepressants, blood pressure agents, diuretics, narcotics, or anti-anxiety medications are each known to produce xerostomia.

Another contributing factor associated with xerostomia is a person's age. It is commonplace that as people age they find that chronic mouth dryness becomes more and more of a problem. With age our salivary glands tend to work less effectively and the composition of the saliva that they produce changes too. Both of these factors create a situation where the effects of salivary cleansing and buffering are reduced.

A factor that compounds the problems associated with mouth dryness is that people who suffer from xerostomia are more at risk for having periodontal disease ("gum disease"). As discussed in our next section, periodontal disease is a causative factor for bad breath.

How does periodontal disease (gum disease) cause bad breath?

Periodontal disease, often just called "gum disease," can be the source of a person's breath problems. Ask any dentist, the odor coming from the mouth of a person with active gum disease can be so distinctive that a dentist will often correctly anticipate the presence of gum problems even before they begin their examination of the patient.

Periodontal disease is the second most common (fundamental) cause of bad breath. Since periodontal disease is typically more of a problem for people over the age of 35 or so, the older we get the more likely that the source of our bad breath is related to conditions associated with the health of our gums.

Periodontal disease is a bacterial infection located in the tissues that surround a person's teeth. Advanced forms of periodontal disease typically result in serious damage to the bone that holds teeth in place. As this bone damage occurs, deep spaces form between the teeth and gums (termed "periodontal pockets"). These pockets provide an ideal location for bacteria to live in.

In many cases it is waste products coming from the bacteria that reside in these periodontal pockets, pockets which are often so deep that a person cannot effectively cleanse them, that is the cause of a person's bad breath. In addition, researchers have found that the amount of coating (as measured by weight) that is present on the tongues of people with periodontitis is greater than those in control groups. They have also found that the level of volitile sulfur compounds coming from this coating is four times greater than in people who do not have periodontal disease.

How can sinus conditions promote bad breath?

Sinus conditions can have an effect on the quality of a person's breath. Upper respiratory infections and allergies can create postnasal drip that deposits onto the back portion of a person's tongue (by way of the oral-nasal pathway found in the area of a person's soft palate). This discharge often has a foul taste and smell. What's worse, oral bacteria will feed upon this discharge and create their own smelly waste products thus adding to the problems the person is having with bad breath.

As a compounding factor, people with sinus conditions will often have stuffed up noses and therefore will have a need to breathe through their mouth. The drying effect of mouth breathing can create an environment that promotes bad breath. Additionally, sinus sufferers are likely to be taking antihistamines, a type of medicine that is known to create mouth dryness.

Can untreated medical conditions cause bad breath?

Although the most common source of breath odors is related to the accumulation of bacteria in the mouth, certain medical conditions can be the cause of a person's breath odors. If a person's bad breath persists after they have consulted with their dentist and tried the usual simple solutions, then a consultation with a medical doctor may be indicated. Your doctor will of course know what types of conditions to look for but, in general, they will look for problems associated with the respiratory (pulmonary or bronchial), hepatic (liver), renal (kidney), and gastrointestinal (stomach and intestine) systems.

What types of dental conditions can cause bad breath?

There can be some types of untreated dental pathology that can contribute the problems a person is having with their breath. Any active infections in a person's mouth, such as those associated with abscessed teeth or a partially erupted wisdom tooth, can cause bad breath. Teeth having extensive untreated decay can trap enough debris and bacteria that they become the source of foul odors. Your dentist can identify and treat these problem dental conditions if they exist.

Can bad breath be caused by dentures?

Dentures (complete dentures, full dentures, partial dentures, etc...) can have a big influence on the quality of a person's breath. If you have dentures try this test to see if they might be the source of your breath malodor:

While the most common cause of breath malodor is that caused by the accumulation of bacteria either on a person's tongue or on and around their teeth (periodontal disease), bacteria can and do accumulate on the surface of dentures and this can be the source of bad breath for some.
More about the causes of denture breath and how to treat it. >>