Donations of spit from about 1500 people are helping scientists understand how the billions of microbes* — mostly bacteria — in our mouths keep us healthy.
Early results of a long-term study by the University of Melbourne, Doherty Institute and Melbourne Museum suggest there are simple things we can all do to look after the communities of bacteria in our mouths, especially by eating healthy food.
The Victorian Oral* Microbiome* and Lifestyle Study aims to better understand the bacteria that live in our mouths and how they vary with different lifestyles, diets, backgrounds and where we live.
As part of the study, almost 1500 visitors to Melbourne Museum’s Gut Feelings exhibition in 2019 donated their spit so the microbes in their saliva could be studied by researchers.
Participants also provided information on topics such as their diet and where they live.
While there are already many studies that look at oral microbiome, capturing the microbial* diversity of Victorians is providing valuable insights* into the Australian oral microbiome, said Dr Andre Mu, lead microbiome researcher for the study and research fellow at the Doherty Institute.
“When predicting health and disease, statistical models that use data from one location may not generalise to other locations.
“For example, we can’t strictly use data collected in the United States to predict a ‘healthy’ microbiome status for Australians.”
WHY ARE THESE MICROBES IMPORTANT?
Research has shown that microbes living within and on our bodies — making up 1kg to 2kg of our body weight — contribute to how the body functions.
Around 700 bacterial species have been found in the human mouth, but each of us is likely to be inhabited by around 300 different species.
Bacteria species in your mouth interact with each other and with you as their host. They help with digestion, can protect you against harmful bacteria, viruses and other microorganisms that cause disease and produce chemicals that are important to your health.
Sometimes, bacteria species can cause disease.
Depending on what we eat, and how we look after our mouths and health, our oral microbiomes can act as guardians, particularly of our teeth and gums, or as invaders.
Just like us, microbes need food to eat and this is plentiful in the mouth. Your saliva, what you eat and the waste products of other microbes, all help nourish your oral microbiome.
Microbes often work together.
“Similar to the algae and molluscs that build up on the bottom of ships, our teeth and gums provide perfect surfaces for entire communities of microbes to be built,” said study leader Dr Julian Simmons of the Melbourne School of Psychological Sciences.
“These communities are called biofilms and are usually made up of a range of microbes that like living together. While some bacteria are initial colonisers, others only move in when conditions are just right.”
The new research suggests our oral microbiomes are becoming less diverse, and our oral health has declined, with modern diets.
We are providing our oral communities with far more sugar and other simple carbohydrates than ever before, and some bacteria convert these sugars into strong acids.
When we eat sugars frequently through the day, acid levels increase, eating away at our tooth enamel* and disrupting the layer of protective bacteria.
Early findings from the study support this, with high carbohydrate intake – like added sugar and refined flours – associated with lower diversity of bacteria in participants’ saliva.
So what can be done to improve your oral microbiome?
“Our current understanding of oral health indicates that supporting a healthy oral microbiome involves reducing the food for bacteria that can cause disease, and regularly disrupting the communities living on our teeth,” said Dr Samantha Byrne of the Melbourne Dental School.
Researchers hope to extend the study to regional areas so the results represent all of Victoria.
You can see the Victorian microbe map at: museumsvictoria.com.au/melbournemuseum/whats-on/gut-feelings/microbe-map/
CARING FOR YOUR ORAL MICROBIOME
Dr Byrne advises there are simple things we can do to live in harmony with and nurture* our oral microbiome, including:
Brush your teeth twice a day. Flossing is important too because it removes dental plaque hiding between the teeth.
Antimicrobial mouth rinses are not needed unless recommended by your dentist, as they will remove good bacteria.
Reduce the total amount and number of times a day you eat sugar.
Eat a varied and healthy diet. Around 88 per cent of adults in the study reported not eating the recommended five serves of vegetables a day.
This is an edited version of a story published on pursuit.unimelb.edu.au and republished with permission.
- microbes: microscopic living things, including bacteria
- oral: to do with the mouth
- microbiome: population of microbes in a place
- microbial: to do with microbes
- insights: learnings
- enamel: hard protective coating
- nurture: look after
- Why did people donate their spit?
- Why are molluscs and algae on ships mentioned in this story?
- What happens to acid levels in our mouth when we eat sugary food? Why is this bad?
- What is flossing good for?
- Explain two ways to look after your mouth microbes.
LISTEN TO THIS STORY
1. Mouth Microbes
Draw a picture of a mouth and label all the types of microbes and bacteria living in it from the information provided in the Kids News article. You could use a red colour for bad things and green colour for the good things.
Time: allow 15 minutes to complete this activity
Curriculum Links: English, Health and Physical Education
Read and reflect on this quote from the Kids News article: “we can’t strictly use data collected in the United States to predict a ‘healthy’ microbiome status for Australians.”
Why would the bacteria found in people’s saliva be different in a different state or country?
Time: allow 10 minutes to complete this activity
Curriculum Links: English, Science, Critical and creative thinking
Read with Penny Punctuation
Pair up with the article between you and stand up to make it easy to demonstrate your Kung Fu Punctuation.
Practice reading one sentence at a time. Now read it again, while acting out the punctuation as you read.
Read and act 3 sentences before swapping with your partner.
Have 2 turns each.
Now as a challenge as your partner to read a sentence out loud while you try and act out the punctuation. Can you keep up?
Try acting out 2 sentences.
Are you laughing yet?
Have fun acting out your punctuation.
HAVE YOUR SAY: What could you do better to look after the microbes in your mouth?
No one-word answers. Use full sentences to explain your thinking. No comments will be published until approved by editors.