From your teeth and breathing to bad breath and general health.

Most of us don’t give our tongue much thought unless we bite it, burn it on a hot drink or suddenly notice something that doesn’t look quite right.

But as a dentist, the tongue is something I pay attention to every day.

It helps us speak, taste, eat and swallow, but its position, movement and appearance can also give us useful clues about what is happening elsewhere in the mouth.

So, what exactly am I looking for?

Where should your tongue rest?

Try something for a moment. Without deliberately changing anything, notice where your tongue is sitting right now.

Ideally, when we are relaxed and not speaking or eating, the tongue should rest gently against the roof of the mouth, with the tip sitting just behind the upper front teeth rather than pushing against them. The lips should be comfortably together and, where possible, breathing should take place through the nose.

That may sound like a very small detail, but our tongue spends many hours each day in its resting position.

And over time, those gentle, repeated forces matter.

What does your tongue have to do with your teeth?

Your teeth don’t exist in isolation.

They sit in a balance between the tongue on the inside and the lips and cheeks on the outside. The way the tongue rests and moves can therefore play a role in where teeth sit and how stable their position is.

This is particularly interesting after orthodontic treatment. Retainers remain essential because teeth naturally have a tendency to move, but function matters too. If the tongue repeatedly pushes against the teeth when resting or swallowing, it may be one of several factors contributing to unwanted tooth movement.

It is one reason I increasingly find myself looking not only at where the teeth are, but also at what is happening around them.

What about children and facial development?

This becomes particularly interesting while a child is still growing.

The jaws and face develop within a complex environment influenced by genetics as well as function. Breathing, chewing, swallowing, tongue posture and oral habits all form part of that environment.

A tongue resting against the palate provides different forces from a tongue that habitually sits low in the mouth, particularly if this is associated with an open mouth posture or mouth breathing.

That doesn’t mean that tongue position alone determines how a child’s face or jaws will develop. Growth is far more complex than that.

But it is one of the reasons I think it is worth paying attention to function early rather than looking only at whether the teeth appear straight.

I touched on this from a different angle in my previous article on mouth breathing in children, and it is an area I will return to in more detail in the future.

And what happens when we swallow?

We swallow hundreds of times every day, usually without thinking about it.

In a mature swallowing pattern, the tongue works mainly against the palate. In some people, however, the tongue moves forwards or sideways against or between the teeth when swallowing. You may hear this described as a tongue thrust.

Not every unusual swallowing pattern requires treatment. But where there are concerns about tooth position, an open bite, orthodontic relapse or oral function, it can be useful to look at how someone is swallowing rather than simply looking at the teeth themselves.

Why is my tongue white?

Now for something completely different, and probably one of the most common tongue related questions.

A white or slightly yellow coating on the tongue is often simply a build up of bacteria, food debris and dead cells on its textured surface.

It can become more noticeable with:

• dry mouth

• dehydration

• mouth breathing

• smoking

• certain foods and drinks

• reduced oral hygiene

• some medications

The back of the tongue is particularly good at harbouring bacteria because of its uneven surface.

A coating that comes and goes is usually very different from a persistent white, red or otherwise unusual area that doesn’t disappear. If you notice a change that persists, particularly an ulcer, lump, red or white patch, it is always worth having it checked rather than trying to diagnose it from pictures online.

Could your tongue be causing bad breath?

Quite possibly.

When we think about bad breath, we often blame the teeth or perhaps something we’ve eaten. But the tongue can be one of the main places where odour producing bacteria accumulate.

These bacteria break down proteins and can produce volatile sulphur compounds, which contribute to that familiar unpleasant smell.

Gum disease, tooth decay, dry mouth and other conditions can also cause bad breath, so persistent halitosis deserves a proper assessment. But keeping the tongue clean can make a noticeable difference for many people.

Do you need a tongue scraper?

You don’t necessarily need one, but tongue cleaning can be a useful addition to your normal oral hygiene routine, particularly if you tend to develop a visible coating or struggle with bad breath.

A tongue scraper can remove coating from the surface of the tongue, but a toothbrush can also be used.

Whichever you choose, gentle is the key word.

There is no benefit in aggressively scraping until the tongue looks perfectly pink. The tongue is living tissue and shouldn’t be scrubbed or scraped until it becomes sore.

And tongue cleaning doesn’t replace brushing your teeth twice daily or cleaning between them.

What about a scalloped tongue?

Another thing people often notice is a wavy or indented outline along the sides of the tongue where it sits against the teeth.

This is commonly called a scalloped tongue.

It can occur for a number of reasons and, on its own, isn’t a diagnosis of a particular health problem. This is worth mentioning because searching for tongue changes online can quickly produce some rather alarming explanations.

The same applies to geographic tongue, where smooth red areas surrounded by pale borders can appear and change position over time. It is usually harmless, although anything you are unsure about should still be assessed properly.

Can your tongue tell you about your gut health?

This is where things become particularly interesting, and where I think we need to separate genuine science from some of the claims we see online.

Our mouths don’t exist separately from the rest of our bodies. The oral microbiome is part of a much larger microbial ecosystem, and researchers are increasingly interested in the relationship between oral health, the gut and general health.

Certain illnesses, nutritional deficiencies, medications and changes in hydration or saliva can also sometimes affect the appearance of the mouth and tongue.

But this doesn’t mean we can look at a tongue and reliably diagnose someone’s gut health.

You may have seen charts online claiming that a particular coating, colour or area of the tongue reveals exactly what is happening in a particular organ. Modern medicine doesn’t support using the tongue in this way as a stand alone diagnostic tool.

Your tongue can sometimes provide clues.

It isn’t a map of your internal organs.

More than just teeth

This is one of the things I find fascinating about dentistry.

A dental examination isn’t simply a search for cavities.

The gums, saliva, tongue, bite, tooth wear, breathing pattern and the way the muscles and soft tissues function can all add pieces to the picture.

Sometimes what I see is completely normal. Sometimes it prompts a simple conversation about tongue cleaning or hydration. And occasionally, it tells me that something deserves a closer look.

So next time you brush your teeth, have a look at your tongue too.

There is rather more going on there than you might think.