Neuropsychological causes 2018-03-23T10:16:44+00:00

Neuropsychological causes

Certain psychological states related to stress or anxiety can cause genuine halitosis. In particular, this is due to the fact that the salivary glands (stimulated by nervous fibres connected to the autonomic nervous system) produce less saliva when a person is stressed or anxious. The stagnation of residual saliva in the mouth increases the production of VOCs and VSCs.

This phenomenon was proven when a group of university students were invited to watch a horror film for 15 minutes, with the students’ breath being measured before and after the projection of the film. This is also known as “lecturer’s halitosis” because of its prevalence among public speakers (who usually need to have a glass of water close to hand).

Distorted sense of taste

However, other psychological and psychiatric conditions by themselves can influence a person’s self-perception and/or even how they believe others perceive their breath. Cases of pseudohalitosis can be due to a number of factors. Some people might notice an unpleasant odour in their exhaled air (when third parties do not), or they might be convinced that they can smell a disagrreable odour after doing any of the following: covering the nose and mouth with their hands; licking their hands; smelling a telephone mouthpiece; smelling dental floss; rubbing their fingers against their gums, tonsils or tongue; or breathing with their head underneath a sheet. This type of patient will often rank higher on obsession/compulsion scales; interpersonal sensitivity, anxiety and psychosis, compared to other patients.

Flawed assumptions about other peoples’ attitudes are also common. Insecurity will often lead a person to place too much importance on or wrongly interpret the attitudes and behaviours of others, for example if somebody opens a window when in their presence; rubs their nose; offers them a chewing gum; lowers their gaze when listening them, etc. Another example of jumping to conclusions would be upon noticing a white coating on their tongue (which is often just a collection of salivary protein deposits) the immediately infer that it is the type of tongue coating that causes bad breath.

Dysgeusia (distorted sense of taste) can cause patients to believe that they have bad breath. The distortion can be influenced by a number of nutritional, hormonal and metabolic factors (among others) which can generate confusion due to close relationship between the perception of smell and taste are. In general, patients with olfactory deficiencies tend to display more concern about their breath.


Halitophobia has recently become a recognised psychiatric condition. People with halitophobia suffer from delusional halitosis (also referred to as psychosomatic halitosis). Many halitophobia suffers of are unaware of their bad breath and refuse to see a psychologist as they do not acknowledge that they have this psychosomatic condition. There is no doubt that these individuals suffer from severe halitosis, even when those closest to them insist that they do not. Certain behaviours of others, such as covering the nose or keeping a lot of distance during a conversation can immediately be interpreted as a sign that the other person is bothered by their breath. This condition can lead to serious problems and traumatic situations in their personal and family lives.

Olfactory reference syndrome is a psychiatric condition characterised by a person’s stubborn belief that they have unpleasant body odour (not only malodour in their exhaled air, like in the case halitophobia, but also from their skin, armpits, genitalia or other parts of the body) and accompanied by considerable shame and distress, which can even lead to social withdrawal. Those suffering from this syndrome display strong characteristics of self-observation, self-criticism, neurosis, inferiority, difficulty in expressing their emotions and obsession. It is very common for those with the syndrome to develop secondary depression.

Hypochondria can also be a trigger for a flawed self-perception of the breath. There are also cases of individuals who become oversensitive due to having a family member who suffers from chronic bad breath.

Tonsil stones do not necessarily produce an unpleasant odour that can be noticed by others. However, having tonsil stones will constantly bother the individual, leading them to believe that they suffer from bad breath.

In recent years, there has been an increase in the number of people seeking treatment for halitosis after noticing that they do not have “fresh” breath. Such excessive demands are a result of the overwhelming number of breath odour improvement products on the market, with the media often being responsible for disseminating this wrong message.



We talk about halitosis open and accessible way, so that you can understand medical terminology that scientists use.

1. What is halitosis?
2. Physical and social consequences
3. Bad breath through the ages


The Breath Institute has discovered, on the basis of the latest international research, that there are over 80 possible causes of halitosis.

1. The composition of halitosis (bad breath)
2. Causes of halitosis (bad breath)
2.1 Oral causes
2.2 Respiratory causes
2.3 Digestive causes
2.4 Systemic causes, diet and habits
2.5  Neuropsychological causes


We identify the most effective clinical methods when diagnosing precisely the halitosis’ origin, so that you can chose the best treatment.

1. Methods of diagnosis
1.1 Self-perception
1.2 Organoleptic tests
1.3 Breath gas measurement
1.4 Laboratory tests
2. Psychological tests
3. Signs and associated symptoms