Ever heard of the oral-gut axis? Here’s how your oral health can impact your gut

How to improve gut health, starting with your teeth.

Like many around me, I’ve recently been paying attention to my gut health. There’s a growing body of evidence that links a diverse gut microbiome (that is, the bacteria in your gut) to positive outcomes for both mental and physical health. Better gut health might mean a reduction in depression and anxiety, increased immunity and even improved heart health.

The best way to improve your gut microbiome is through diet, according to researchers. The shortcut often cited is to eat 30 different plants a week. I recently learnt, however, that there’s another simple way to boost (or harm) your gut health: oral hygiene.

Move forward in your wellness journey over at our Health section.

At a recent (gifted) trip to Dr Daniel Tan and Associates, a Launceston-based integrative practice that takes a holistic approach to dental health, I was surprised to learn something as simple as tongue scraping could improve my gut health.

“We should stop thinking of the mouth as separate from the rest of the body,” explains Daniel, who is guided by the principles of bioregulatory medicine. “It’s the very beginning of the digestive system and what happens there has flow-on effects throughout our body.”

Introducing the oral-gut axis

If you think about it, it makes sense. Known as the oral-gut axis, this link recognises how the mouth and the gut communicate with each other. “They’re not separate systems, they’re part of one continuous digestive pathway,” explains Daniel.

“We know that gut health is central to much more than digestion, it can influence immunity, energy, even mental wellbeing. Because these bacteria from our mouth feed directly into the gut, oral health becomes a key part of this bigger picture.”

He explains that every time we swallow, millions of bacteria from the mouth make their way into our gut. When the oral microbiome is healthy, these bacteria support a balanced gut microbiome. “On the other hand, if harmful bacteria dominate, for example with gum disease, they can disrupt that balance and trigger inflammation,” he says. Similarly, changes in the gut can sometimes show up as issues in the mouth.

A healthy mouth

As someone who has long considered oral hygiene as a way of avoiding cavities and bad breath, it’s encouraging to know my twice-daily routine has a wider impact on my overall health.

Still, I can’t quite wrap my head around the idea that millions of bacteria (“and other organisms,” adds Daniel) live in my mouth. It’s a “well-run ecosystem” known as the oral microbiome.

Daniel assures me most of these microbes are actually very beneficial. “They help protect the teeth and gums, assist in breaking down food and keep harmful bacteria under control. Problems will only arise when this balance is disrupted. For example, excess sugar, smoking or gum disease will allow the harmful bacteria to take over.

According to Daniel, sugar feeds harmful bacteria while fibre-rich foods help maintain balance. Lifestyle factors such as smoking, alcohol, stress and even sleep quality can also shift the mix. Certain medications, especially antibiotics, have an impact too, wiping out both helpful and harmful species.

“The oral microbiome is dynamic and it responds directly to how we live and care for ourselves. That means the daily decisions we make, from what we eat to how we manage stress, can actively shape both our oral and gut health,” he says.

So, how can I improve my oral microbiome?

In good news, anyone already paying attention to their gut microbiome is probably going to be supporting a healthy oral microbiome, given the two are so closely linked. When I ask Daniel for his best advice to improving my oral health, his tips are hardly surprising.

Brushing twice daily and flossing once daily remove harmful bacteria before they can travel into the gut. Regular dental check-ups ensure problems like gum disease are picked up early, which help prevent ongoing inflammation that can influence gut health.

“Stay hydrated. Adequate hydration supports saliva flow, which is the body’s natural way of neutralising acids and washing away bacteria,” he explains.

“Fibre-rich foods and whole foods encourage a more balanced oral and gut microbiome,” he adds, noting we should limit added sugars to keep harmful bacteria under control.

Finally, he encourages a list of supportive lifestyle habits, which should come as no surprise to anyone paying close attention to their overall health. “Not smoking, moderating alcohol, managing stress and prioritising sleep all support a healthier oral microbiome, which in turn supports a healthier gut,” he says.

“The good news is that small, consistent habits can all make a real difference. By looking after the mouth, we’re really looking after the whole body.”

To book an appointment with Dr Daniel Tan and Associates, head here.