Bad Breath

Halitosis is the medical name for breath that carries an unpleasant odour. It isn't a condition in its own right — it's an outward sign of something else going on. Most of the time that means bacterial load and soft-tissue health inside the mouth; less often, it goes hand in hand with a respiratory or digestive issue. There's no way to tell which cause is behind it from the smell alone; that distinction is made through a clinical examination and imaging where needed.

No, it isn't. Saliva flow slows down while you sleep, the mouth dries out and bacteria multiply more easily, which is why almost everyone wakes up with some odour — and why it eases once you brush. Garlic, onions, spicy food, coffee and alcohol cause temporary breath odour too; because these compounds enter the bloodstream and are released through the lungs, brushing alone may not clear the smell straight away. Fasting or a very low-carbohydrate diet can also cause temporary odour. What all of these have in common is that they settle on their own within a few hours or days. What's worth paying attention to is breath odour that lasts for days or even weeks and keeps coming back despite brushing — persistent bad breath isn't something you should expect to clear up by itself.

Stomach-related odour is possible, but the valve between the stomach and the mouth normally stays shut, so a constant flow of smell from below isn't what you'd expect. Reflux, sinusitis and post-nasal drip, tonsil stones, poorly controlled diabetes, and advanced kidney or liver disease are among the causes that sit outside the mouth, each with its own additional signs. This is why assessment usually starts with the dentist: looking for a systemic cause before ruling out causes inside the mouth only lengthens the process. Once these are ruled out through examination and imaging where needed, attention turns to the possibilities beyond the mouth, and a referral to the appropriate specialist — an ENT doctor or a physician, for example — comes into the picture at that stage.

Your sense of smell adapts to an odour it's constantly exposed to — this is known as olfactory adaptation. Not being able to smell your own breath doesn't mean there's nothing there. Breathing into your cupped hands isn't a reliable test either, since the odour mainly comes from the back of the tongue. Asking someone close to you for an honest opinion, or having it assessed at a dental check-up, are more realistic ways to find out.

It helps to read this symptom alongside whatever comes with it, rather than on its own. Bleeding when you brush, red or tender gums, loose teeth, pain on biting, a persistent metallic or bitter taste, waking up with a dry mouth, and a thick whitish coating on the back of the tongue are the most common companions. When several of these appear together, it makes an inside-the-mouth cause more likely.

These mask the smell for a while; they don't remove its source. Products containing mint or menthol give a feeling of freshness, but as long as the bacterial coating on the tongue, tartar or an infected root stays where it is, the odour comes back. Using a high-alcohol mouthwash frequently can actually work against you by increasing dryness in the mouth. It's more accurate to think of mouthwash not as a solution but as something that, where appropriate, supports treatment alongside it.

What helps is simple: brushing with a soft brush twice a day, using interdental brushes or floss, cleaning the tongue gently, drinking water throughout the day, and stopping smoking. What to avoid matters just as much. Scrubbing with bicarbonate of soda, lemon juice, vinegar or salt wears down the enamel surface and can burn the gums. Scraping the tongue too hard irritates its surface. Trying herbal mixtures found online creates the conditions for underlying decay or gum disease to progress quietly in the background. Taking over-the-counter medication or antibiotics without a prescription isn't the right approach either.

The examination is structured to narrow down where the odour is coming from. The dentist measures how easily the gums bleed and how deep the pockets are, checks for decay and leaking fillings, and assesses the coating on the tongue and how much saliva is present; if you wear a denture, its fit and the tissue underneath are examined too. An X-ray can reveal decay between teeth that isn't visible to the eye, and infection at the root tip. When the symptom started, what makes it worse, and any medication you're taking are all part of the history-taking as well.