Why can’t we smell our own breath?

Why can't we smell our own breath?
Image: iStock

Occasionally, we all worry about our bad breath, but are our fears mainly in our heads or is Halitosis really there?

Surely you have ever wondered if you have bad breath. In fact, there is a term for the fear of bad breath: Halitophobia. One study showed that 80% of patients visiting a particular dental clinic thought they had bad breath (also known as “halitosis”) when only 24% of them actually had it.

Such an exaggerated concern probably arises from the fact that we can’t really smell our own halitosis. As a result, we fear we’re unleashing a burst of dragon breath every time we talk to someone.

There are reasons why we can’t smell our own breath, but they are hypotheses at best. First is the theory that we are too used to our own body odour, collects ‘HowStuffWorks‘. The same can also happen with our living environment. Have you ever noticed that you can’t detect the subtle smell of your home until you return from vacation? The same can apply to your breath; maybe you’re too used to it.

Another reason might be that our breathing is released differently during the conversation than during breathing. When you talk, the back of your mouth, which is where the halitosis comes from, is more likely to be stirred.

The next idea is that our inability to smell our own breath, or the inside of our noses, is an evolutionary development. According to this particular theory, it would overwhelm the nose to constantly capture the smell of breath beneath it, and this would prevent it from detecting other smells more critical to safety and survival. As a result, the mind learned to block the smell of the nearest neighbour of the nose.

Finally, a more recent assumption is that the smell is not powerful enough to last during the exhalation and inhalation process in a person. Therefore, any halitosis a person may have dissolved before their nose can detect it. However, if person A breathes on person B, person B can smell it because they only have to inhale person A’s breath, not exhale it first.

So how can you tell if you’ve got bad breath? Common methods include licking and then smelling the inside of the wrist or examining the tongue in the mirror to see if it is covered. If you prefer an official response, you can request a breath test kit or have your dentist perform a Halimeter test.