Have you ever spoken to someone and noticed an unpleasant smell coming from their mouth? Or perhaps someone has quietly told you that you have bad breath?

Bad breath, medically known as halitosis, is common and can affect anyone. Although often seen as an embarrassing social problem, persistent, bad breath can signal an oral health problem. It can affect confidence and quality of life.

What is halitosis?

Halitosis is the medical term for an unpleasant smell coming from the mouth. Morning breath, for example, is common because saliva production decreases during sleep. Saliva normally helps clean the mouth and control bacteria. When saliva decreases, bacteria and food debris can build up and produce an unpleasant smell. This usually improves after brushing or eating.

Persistent, bad breath despite good oral hygiene deserves attention.

Types of halitosis

Halitosis can occur in several forms. Physiological halitosis is usually temporary and may occur after sleeping, fasting or eating strongly flavoured foods such as garlic and onions.

Pathological halitosis is linked to an underlying health problem. Most persistent cases are caused by conditions inside the mouth, including gum disease, tooth decay and a heavily coated tongue. Less commonly, the cause may be outside the mouth, such as conditions affecting the nose, throat or respiratory system.

Some people believe they have bad breath even when no unpleasant smell can be detected. This is known as pseudohalitosis. Persistent fear despite reassurance may be called halitophobia.

What causes bad breath?

The mouth contains many types of bacteria. When some bacteria break down food particles, dead cells and other materials, they produce chemicals with unpleasant smells called volatile sulphur compounds.

A coated tongue can collect bacteria, dead cells and food particles. Gum disease allows bacteria to build up around the gums and teeth, while deep or untreated tooth decay can

trap food and bacteria. Poor oral hygiene allows plaque and debris to accumulate, while dry mouth makes it easier for bacteria to build up.

Food trapped between teeth, poorly cleaned dentures, infected teeth and infections around partially erupted wisdom teeth may also cause unpleasant breath. Smoking and some medicines can also contribute.

Does bad breath come from the stomach?

Many people believe bad breath comes from the stomach. However, most persistent, bad breath begins in the mouth. Some nose, throat or lung conditions can also contribute. Persistent, bad breath should therefore be assessed rather than blamed on a stomach problem.

How is halitosis diagnosed?

A dentist can help identify the cause. The dentist will ask about your symptoms and health before examining your teeth, gums, tongue and mouth.

The examination may identify gum disease, tooth decay, infections or dry mouth. People may also have difficulty noticing their own breath.

How can bad breath be treated?

Treatment depends on the cause. Good oral hygiene is the first step. Brush your teeth twice a day with fluoride toothpaste, clean between your teeth daily and gently clean your tongue, especially toward the back.

Drink enough water, avoid tobacco, and seek professional treatment for gum disease, tooth decay or infection. Dentures and appliances should also be cleaned properly.

Mouthwash may help in some cases, but it should not simply hide persistent, bad breath. Covering the smell is not the same as treating the cause.

Prevention and when to see a dentist

Preventing bad breath starts with good oral hygiene, regular dental check-ups, cleaning between the teeth and tongue, drinking enough water and avoiding tobacco.

Most importantly, persistent, bad breath should not be ignored. If bad breath continues despite good oral hygiene, visit a dentist. A dental professional can identify the cause and provide appropriate treatment or recommend further medical assessment.

Bad breath may seem like an embarrassing problem, but sometimes it is the mouth's way of telling you that something needs attention. Do not be embarrassed to seek help.

Visiting a dentist can lead to proper treatment, better oral health and renewed confidence. A healthy mouth is part of a healthy life.

The writer is an oral health advocate and dental student at the University of Rwanda.