What are the causes of bad breath?

Dentist and Head of Clinical Services at Bupa UK
25 April 2018

Having bad breath can be unpleasant and embarrassing, especially if you don’t know what’s causing it. It’s not uncommon to experience bad breath for a short time, for example after eating certain foods, or when you wake up. But it can also be longer-lasting, and you may not know what’s causing it.

The experts in the Bupa UK dental team are on hand to explain some of the reasons behind bad breath.

Medical causes of bad breath

Dr Ian Kelly, Dentist, looks at some of the medical conditions that can cause bad breath.


Do any medical conditions cause bad breath?

The presence of decay - like a rotten tooth - will contain a lot of bacteria. Gum disease whereby the gum detaches from the tooth, forming pockets. Bacteria obviously will reside here, causing the same sorts of problems.

Other reasons behind bad breath

Dr Ros O’Leary, Periodontist, explains that other factors such as lifestyle can also contribute to bad breath.


What causes bad breath?

Most common causes are to do with oral bacteria, so whether it’s inflammation of your gums with a lot of really nasty bacteria in and around. It can often come from your tongue. Some people have quite rough surfaces to their tongue, and they retain a lot of bacteria. It can be things like infections in your mouth, which is rarer. Or it can be open decay, which is also rarer. It can sometimes be, and very rarely, due to gastric reflux and problems from the stomach. But, it’s more common orally.

People who smoke tend to have bad breath. People who drink a lot of coffee tend to have bad breath. So there are habits that you can do that can also make the situation worse. But, the fundamental thing is that your teeth need to be clean, and that is where you would start.

Dr Steve Preddy
Dentist and Head of Clinical Services at Bupa UK

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