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What is bad breath?

Bad breath, often called halitosis, is usually described as a foul or unpleasant smell or taste from the mouth. It can often be a source of embarrassment and anxiety but rest assured it’s entirely treatable. It is a common condition with around 30 per cent of the population suffering regularly from it. In the vast majority of cases, the cause can be found in the mouth region, meaning halitosis can be easily treated by having great healthy teeth and gums!

Symptoms of bad breath

The symptoms of bad breath are usually easy to spot in that it’s a noticeable unpleasant odour emitted from the mouth. Sometimes it might not be easy to assess your own bad breath so you may need to ask a relative or close friend to confirm.

Speak to a dental professional today

Our dentists have all the experience, skill and technology required to diagnose and treat your bad breath. Arrange an appointment with our dental team at our central London dental clinic, situated on the prestigious Wimpole Street.

What is the most common cause of bad breath?

Bad breath has multiple potential causes but usually foul smells are caused by undesirable bacteria. Excessive build-up of these bacteria will result in halitosis.

Poor oral hygiene

Plaque buildup as a result of oral hygiene not being up to scratch will result in bacteria build up, the main factor in halitosis. If the neglect is continued it can result in gum disease (periodontitis), which means pockets will be established inside the gums where even nastier bacteria end up thriving. This is the main (scary!) reason why you should see your dentist if you think you may suffer from bad breath.


Smoking not only creates an unpleasant mouth odour as a by-product of tobacco, but it also increases the chances of contracting gum disease.

Decay and Poorly fitted restorations

Poorly fitted crowns, bridges and decay running wild will certainly result in build-up of nasty bacteria, which naturally results in an unpleasant breath.


Oral infections following a tooth extraction for instance can sometimes cause an unpleasant odour and can contribute to bad breath.

Impacted wisdom teeth

Wisdom teeth are usually difficult to clean, but the ones that have not fully erupted and are stuck halfway through the gum can easily result in a food trap. Food debris that stays in these regions starts to rot, leading to a foul smell.

Dry mouth

Natural saliva in your mouth helps remove particles that can lead to bad breath. Some patients may have a condition called xerostomia that decreases the natural production of saliva. Dry mouth is often apparent during sleep, which is why many patients might complain of ‘bad morning breath’.


Bad breath during pregnancy is a common complaint by many an expectant mother. There are a number of reasons why a pregnant woman might experience bad breath more than usual. Hormonal changes in estrogen and progesterone can exacerbate the gums’ response to dental plaque, resulting in inflamed gums. Swollen gums can make oral hygiene more difficult and lead to the formation of pockets where remnants of food get stuck. Furthermore, pregnant women may unfortunately experience morning sickness. Frequent vomiting leads to an unpleasant odour that lingers in the mouth and leads to bad breath.

Reflux disease

Conditions such as GERD (gastroesophageal reflux disease) cause reflux of unpleasant stomach acids that often reach the mouth. This can be an important factor in halitosis.

How do you fix bad breath?

It is most advisable that you see your dentist if you suspect bad breath as it is unlikely that you can resolve the problem on your own. What the dental professionals can do to help you:

  • Ensure that your teeth are spotlessly clean, with all tartar and plaque removed. A great hygienist with fantastic equipment will be most helpful.
  • If the cause for the smell comes from old dental work, one could consider replacing it.
  • Consider removing impacted wisdom teeth which are impossible to clean. Initially, one could simply flush out any debris and advise rinses with anti-septic mouthwashes.
  • Maintain a healthy oral routine – that means brushing your teeth twice a day for two minutes each time. Flossing or cleaning in between your teeth once a day will help avoid food debris accumulating.
  • Quit smoking! This not only helps reduce bad breath but will also protect your long-term health.
  • Attend regular dental appointments so that your dentist/hygienist can spot and prevent any potential issues that might cause bad breath.
Prof Christian Mehl

Written by: Prof Dr Christian Mehl

A certified implantologist and prosthodontics specialist with 20+ years in dentistry, I conduct clinical research, teach at University of Kiel, and contribute to implant system development. Recipient of the Camlog Research Award, I frequently publish and deliver global lectures.

Clinically reviewed by: Dr Raul Costa

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Written by: Prof Dr Christian Mehl

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Written by: Prof Dr Christian Mehl

Medically reviewed by: Dr Raul Costa

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