Blog article

Meet your oral flora: The good, the bad, and the smelly

By HBF

2 minutes

13 February 2025

You’ve probably heard about gut health and how important it is for your overall wellbeing, but did you know your mouth has its own community of bacteria too?

It’s called your oral flora and keeping it balanced is key to maintaining a healthy smile. Just like your gut microbiome, your mouth is home to bacteria, fungi, and other tiny organisms that play a big role in your oral health. When everything is in harmony, your teeth and gums stay protected – but when things get out of balance, that’s when problems can start.

In this blog, we explore how our oral flora works and what you can do to keep it healthy.

The good, the bad, and the smelly

Your mouth is home to a mix of helpful and harmful bacteria, each playing a different role in your oral health. The goal? Keep the good ones thriving while keeping the troublemakers in check.

The good:

Streptococcus salivarius K12: This powerhouse bacteria helps suppress harmful pathogens like Streptococcus pyogenes and Streptococcus pneumoniae, which can lead to infections and autoimmune disorders. It also supports immune health, helps reduce symptoms of oral and respiratory infections, and maintains the health of your ears, nose, and throat.¹

The bad:

Streptococcus mutans: This sugar-loving bacteria turns the sweet stuff into acid, which erodes tooth enamel and causes cavities.²
Actinomycetes: While normally present in the mouth, these bacteria can contribute to tooth decay and gum disease if left unchecked.³

The smelly:

Sulphur-producing bacteria: Found on the tongue, these bacteria release foul-smelling compounds that can cause bad breath.⁴

By keeping the right balance of these bacteria, you can maintain a healthier, happier mouth.

5 simple ways to support your oral flora

A healthy mouth starts with good habits. Here’s what you can do to keep your oral flora in balance:

Brush like a pro: Brush for two minutes, twice a day, and don’t forget to floss!
Use fluoride toothpaste: Fluoride helps strengthen enamel and protect against decay.⁵
Clean your tongue: Use a tongue scraper or gently brush your tongue to remove bacteria.
Stay hydrated: Drinking water keeps your saliva flowing, which helps protect your teeth.⁶
Visit your dentist regularly: Schedule dental check-ups and cleanings every six months to maintain oral health and address any concerns promptly.

How your diet affects your oral bacteria

What you eat and drink plays a big role in the type of bacteria that call your mouth home. A diet high in sugar and processed carbs gives harmful bacteria the fuel they need to thrive.⁷ But it’s not just food – drinks like alcohol can also impact your oral flora, reducing saliva production and creating a drier environment for bad bacteria to grow.⁸

Cutting down on sugar, eating more fresh fruits and vegetables, and staying hydrated can all help promote a healthier mouth.⁶

Other ways to support your oral health:

Avoid smoking and vaping: Research shows that smoking and nicotine use can alter the balance of bacteria in your mouth, lungs, and gut.⁹
Think before using mouthwash: Some mouthwashes can disrupt your oral microbiome. Ask your dentist which products are best for you.¹⁰
Get regular check-ups: We know we beat this drum a lot, but it’s for good reason! A visit to the dentist isn’t just about fixing problems – it’s about preventing them before they start.

Your oral flora plays a huge role in keeping your teeth and gums healthy. By making a few simple changes to your routine, you can help the good bacteria thrive and keep your smile in top shape.

Sources:

¹ScienceDirect: Streptococcus salivarius

²Microbiology Spectrum: The Biology of Streptococcus mutans

³StatPearls: Actinomycosis

⁴Better Health Channel: Halitosis or bad breath

⁵HealthWA: Fluoride and protecting your teeth from tooth decay

⁶Better Health Channel: Tooth Decay

⁷Better Health Channel: Sugar

⁸Microbiome: Drinking alcohol is associated with variation in the human oral microbiome in a large study of American adults

⁹Journal of Translational Medicine: Smoking and microbiome in oral, airway, gut and some systemic diseases

¹⁰International Dental Journal: Mouthwash Effects on the Oral Microbiome: Are They Good, Bad, or Balanced?

Disclaimers:

^For eligible HBF members with extras cover at HBF Dental Centres. Check-up and clean include comprehensive examination, scale and clean, fluoride treatment and up to 2 x-rays, as clinically necessary. Limit of one visit per person per calendar year, waiting periods and other exclusions apply. Learn more at hbfdental.com.au

*Eligible members can claim one fully covered scale and clean per calendar year when provided by a Member Plus dental provider. Benefit is payable subject to annual limit. Percentage benefits apply only when the provider charges in accordance with the Member Plus schedule fee. If the provider charges above the Member Plus schedule fee, you will have a larger out of pocket cost. Member Plus dental arrangements available in WA, NSW, VIC, QLD, and ACT only.

This article contains general information only and does not take into account the health, personal situation or needs of any person. In conjunction with your GP or treating health care professional, please consider whether the information is suitable for you and your personal circumstances.