What Causes Bad Breath

What causes bad breath and where it originates in your body

97% of bad breath is caused by foul smelling gasses which are emitted from anaerobic bacteria (bacteria that thrive in oxygen deprived environments) as a by-product from the act of digesting proteins. These proteins are found in food particles, dead cells, blood, and mucus. The majority of the foul smelling gasses produced by bacteria are volatile sulfur compounds (VSC), however some of the gasses that cause bad breath are not sulfur derived such as acetone, ammonia, dimethyl amine and trimethylamine. In this article we will call, volatile sulfur compounds and the non-sulfuric compounds that cause bad breath volatile organic compounds (VOC).

VOC's are the gases in breath that give it an unpleasant odor. There are several types of volatile organic compounds and each one has a distinct smell to it, that is why you may have noticed that bad breath from different people doesn't always smell alike.

There are over 600 types of bacteria found in the average mouth, some are these bacteria are beneficial and do not produce VOC's. A person who has chronic halitosis has an unhealthy imbalance in their oral flora, meaning that the bad breath causing bacteria have taken over and are producing VOC's at a high rate.

What causes an unhealthy oral flora?

The factors that cause an unhealthy imbalance of oral flora of too much bad breath causing anaerobic bacteria are simple. Give anaerobic bacteria a friendly environment (low oxygen, dry mouth, slightly acidic), a constant food source (poor oral hygiene), and time and pretty soon you will have a mouth teeming with anaerobic bacteria that produce bad breath.

Here is a list of conditions that contribute to the growth of anaerobic bacteria by creating a favorable environment or food source for them:

• Poor oral hygiene
  Poor or not brushing, flossing, tongue scraping, using mouthwash. Essentially not mechanically removing food particles, dead cells, or other proteins from your mouth is poor oral hygiene. Over time, having poor oral hygiene exacerbates the problem of bad breath due to a build up of tartar, plaque, and can cause other medical conditions that help the bacteria population grow.

• Dry Mouth (xerostomia)
  May be caused by diet, medications, medical conditions, and other factors. A dry mouth is good for bacteria because there is less saliva in a dry mouth. Saliva has oxygen in it which kills anaerobic bacteria. A dry mouth is the main reason why it is common to suffer temporary halitosis in the morning (morning breath) because saliva circulation and production is reduced while sleeping. Learn more about dry mouth and how to get rid of it by reading our article on Dry Mouth (Xerostomia).

• Sinus infections, throat infections, postal nasal drip and allergies
  These conditions usually cause an increased amount of mucus. Mucus contains large amounts of proteins that anaerobic bacteria feast upon, which in turn leads to bad breath. For sinus and throat infections, seek the help of qualified professionals. For chronic conditions such as allergies and post nasal drip, read our article on post nasal drip to learn what causes excess mucus and how to prevent it.

• Tonsilloliths (tonsil stones)
  Food particles and other matter can find themselves lodged into the crypts of the tonsils, where the become calcified and turn into tonsil stones. In a study in 2007, 75% of people who had tonsil stones also suffered from halitosis. To learn more about tonsil stones and how to remove them and prevent them from forming, check out our article on tonsil stones.

• Oral Infections
  Oral infections such as tooth decay, cavities, wisdom tooth infections, and mouth lesions cause halitosis due to tissue breakdown, putrefaction of amino acids, and decreased saliva flow.

• Gum Diseases
  Gum diseases such as gingivitis and periodontitis can cause bad breath. These diseases cause bad breath because not only are dead cells (caused by the disease) metabolized by anaerobic bacteria, but also living tissues and bone are eaten away by the bacteria, producing large amounts of VOCs.

Where bad breath originates in your body

We have learned bad breath is caused by odor causing bacteria that break down proteins, but where do these bacteria originate?

• The Mouth
  85% - 90% of halitosis cases are caused by anaerobic bacteria in the mouth: the tongue, teeth and gums.

• Upper Respiratory Tract
  8% - 10% of halitosis cases are caused by anaerobic bacteria in the upper respiratory tract: the nose, sinuses, tonsils, throat and larynx. There are common infections are medical conditions that can cause bad breath in these regions such as tonsil stones, tonsillitis, rhinitis (runny nose) and post nasal drip. In each of these conditions, it is proliferation of volatile organic compound producing bacteria in these areas that cause bad breath.

The vast majority of cases of bad breath are caused by anaerobic bacteria in the mouth and upper respiratory tract, however there are other ways and other areas where it is caused.

• Halitosis from the lungs (Stomatodysodia)
  Bad breath originates sometimes from the lungs due to diseases are medical conditions such as lung cancer, bronchitis, pulmonary abscess, tuberculosis, emphysema, pneumonia and other bronchial or pulmonary infections. Dieting or fasting can result in the body burning fats which produces ketones (such as acetone) in the bloodstream. These ketones are then excreted through the lungs.

• Halitosis from the stomach
  Although rare, bad breath may in some cases originate from the stomach. Medical conditions such as acid reflux disease (GERD), gastritis, irritable bowel syndrome (IBS), or any other condition that causes chronic vomiting or chronic indigestion may cause bad breath due to the acids and partially digested food particles that end up coating the esophagus, throat and oral cavity.

Bad Breath Caused By Foods

There are certain foods to avoid that cause bad breath. Some foods are prone to cause a foul smell to develop on peoples breath more quickly than others. It is common knowledge that foods like garlic and onions cause bad breath but there are more that either lead to a rapid growth in anaerobic bacteria or naturally have smelly odors that smell similar to the VOC's that anaerobic bacteria produce.

To learn more about this read our article on Foods that Cause Bad Breath and How To Get Rid of Garlic Breath.

How To Get Rid of Bad Breath

We learned that bad breath is caused by an overgrowth of bad breath producing anaerobic bacteria. In order to get rid of bad breath, one has to remove the factors that lead to an overgrowth of bacteria in the first place. The factors that lead to an overgrowth of bacteria are shown above with the leading one being poor oral hygiene. Through proper oral hygiene one is able to remove the food source of the bacteria and make their mouths less hospitable to the bacteria. Consistent proper oral hygiene will reduce the population of anaerobic bacteria until they reach healthy low levels where bad breath is not a problem or detectable. The most important part of proper oral hygiene is the mechanical removal of proteins and other particles that the bacteria feed upon.

Read our informative article on How To Get Rid Of Bad Breath to learn more about how to treat bad breath.