Bad Breath Causes


The main cause of Bad breath (Halitosis) is a proliferation of certain types of bacteria in your mouth.

Generally these “bad breath” bacteria are anaerobic (non-oxygen breathing) bacteria. These bacteria live in colonies all over your mouth in a slimy layer called a biofilm.


These anaerobic bacteria feed on the protein rich foods that we eat. Elements of protein rich food becomes trapped in mucous.  Mucous in the mouth, tongue, throat & sinuses coats these unhealthy Biofilms providing “food” for these anaerobic bacteria. Gases released as a by-product of this process cause bad breath. Biofilms are everywhere in the mouth whether they are healthy or unhealthy.


9 reasons why unhealthy bad breath causing Biofilms occur or thrive -


  1. Poor dental hygiene Food trapping in & around teeth
  2. Failed dentistry
  3. Gum infections
  4. Respiratory tract infections  leading to excessive mucous production
  5. Certain foods, the worst culprits being all dairy products, protein rich foods, garlic, onions, coffee & foods that contain sugar.
  6. Cigarette & or cigar smoking or chewing tobacco
  7. Having a “Dry Mouth” (Xerostomia) caused by a multitude of things such as salivary gland problems, “mouth breathing”, caffeine and alcohol intake, recreational drugs, dehydration, prescribed medications. Regarding prescribed medications did you know seven out of the top ten prescribed medicines have dry mouth as a side effect of usage? These are high blood pressure tablets, birth control pills, nasal decongestants, antidepressants, antihistamines, indigestion medication & hormone replacement therapy.
  8. Acidic foods such as fruit juices & coffee can make “dry mouth” worse.
  9. Certain illnesses including liver, lung, kidney, sinus & reflux diseases, diabetes.


NB “Pseudo halitosis” or “halitophobia” is a psychiatric illness where a person may perceive that they have bad breath, but it is not noticed by oral-health-care professionals, friends, family or even extremely sensitive gas chromatography equipment.

Milford Dentists