What Is the Oral Microbiome?

 

Your mouth is home to one of the body’s most complex ecosystems. It contains bacteria, fungi, and viruses that live on every surface including teeth, gums, tongue, and cheeks. Together they form the oral microbiome, a living community that protects against disease, supports digestion, and maintains immune balance.

Each microbe has a specific function. Some regulate acidity, others prevent harmful bacteria from attaching to tissues. This balance is essential for health because the oral microbiome connects directly with the gut and bloodstream.

 
Key takeaway:

A healthy oral microbiome is not only about fresh breath. It supports the digestive system, immune response, and overall microbiome balance.

What the Numbers Reveal About the Oral Microbiome

Illustration of bacteria cells with a blue outline on a white background

90

M+

Microbial cells in just one millilitre of saliva

1

%

Of adults experience chronic oral symptoms without realising it is caused by microbial imbalance
Icon of a blue DNA double helix on a white background

1

%

Of arterial plaques contain oral bacterial DNA

1

%

Of gut microbes trace their origin to the mouth

The Science Behind a Healthy Mouth

A healthy mouth depends on cooperation among beneficial bacteria. These species help maintain balance by controlling acid levels, supporting enamel repair, and limiting the growth of harmful microbes.

The oral microbiome also begins the process of digestion. It produces enzymes that break down starches and fats before food reaches the stomach. Saliva adds proteins and minerals that help maintain microbial stability and protect oral tissues.

When this harmony is disturbed through stress, poor diet, or excessive antibacterial use, harmful species gain dominance, increasing the risk of inflammation and disease.

Key takeaway:
Your oral microbiome is a living laboratory that constantly regulates chemical reactions and keeps your mouth in balance.
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How Your Oral Microbiome Begins

Birth

The First Microbes

Your oral microbiome begins forming the moment you are born. As you pass through the birth canal or meet your first surroundings, microorganisms start to colonise your mouth. Early feeding, whether through breastfeeding or formula, shapes which species thrive and which do not. These first microbes lay the foundation for your lifelong oral and immune health.
Childhood

Building the Foundation

As your first teeth appear, your oral microbiome becomes more diverse. Each new tooth provides a new surface for bacteria to grow and interact. Diet, brushing habits, and even antibiotic use during childhood can all influence how this microbial community develops. A healthy oral microbiome in early life helps strengthen the immune system and supports healthy growth.
Adulthood

The Balance Stage

In adulthood, the oral microbiome reaches its most stable state. When balanced, it supports fresh breath, strong gums, and healthy teeth. It also produces compounds that protect against harmful bacteria entering the bloodstream. Research now shows that an unbalanced oral microbiome is linked to systemic conditions such as cardiovascular disease, Alzheimer’s, and diabetes, proving how closely the mouth is connected to the rest of the body.
Imbalance

When Things Go Wrong

Stress, smoking, processed foods, and poor oral hygiene can disrupt the delicate balance of your oral microbiome. This allows harmful bacteria to multiply, leading to inflammation, cavities, and gum disease. Over time, these bacteria can enter the bloodstream, contributing to broader inflammation in the body and raising risks for other chronic conditions.
Restoration

Finding Balance Again

Understanding your oral microbiome is the first step toward restoring balance. With proper testing, nutrition, and personalised oral care, you can support beneficial bacteria and reduce harmful ones. This balance not only protects your mouth but strengthens your immune system, enhances your energy, and supports long-term health across your entire body.

What Disrupts the Oral Microbiome

Several daily factors can disturb the microbial balance and lead to oral imbalance.

Lifestyle and Habits

Diets rich in sugar or processed foods feed acid-producing bacteria and lower oral pH.

Smoking and alcohol alter the environment inside the mouth, reducing oxygen and damaging beneficial microbes.

Chronic stress changes saliva composition, making it less protective.

 

Hygiene and Medication

Overuse of antiseptic mouthwash eliminates both harmful and beneficial bacteria, disrupting natural balance.

Frequent antibiotic use reduces microbial diversity and delays recovery of healthy flora.

Inconsistent brushing or poor flossing habits allow pathogenic biofilms to form on teeth and gums.

 

Environmental and Biological Factors

Dehydration limits saliva flow, removing one of the mouth’s main defence mechanisms.

Hormonal changes during puberty, pregnancy, or menopause can alter microbial composition.

Poor sleep and weakened immunity make it easier for opportunistic species to dominate.

 

Why You Should

Check Your Oral Microbiome

 

We believe everyone should know the state of their oral microbiome.

When this delicate ecosystem becomes imbalanced, it can lead to more than just cavities or bad breath. An unhealthy oral microbiome has been linked to gum disease, inflammation, cardiovascular problems, and even cognitive decline.

Your mouth is the gateway to your body, and what happens here can influence the rest of your health. Testing your oral microbiome regularly helps you stay ahead of imbalances and take action before symptoms progress.

Common signs of an imbalanced oral microbiome include:

Persistent bad breath even after brushing

Bad breath that does not go away with brushing or mouthwash often signals an overgrowth of harmful bacteria that produce sulphur compounds in the mouth.

Bleeding or swollen gums

This is a sign of inflammation caused by bacterial imbalance, which can irritate the gum tissue and increase the risk of gingivitis and periodontal disease.

Tooth sensitivity or frequent cavities

When protective bacteria are reduced, acid-producing microbes become dominant, weakening enamel and making teeth more prone to decay and sensitivity.

White coating on the tongue

A thick or persistent white layer can indicate an overgrowth of bacteria or yeast species and shows that the mouth’s microbiome is struggling to maintain balance.

Dry mouth or changes in saliva

Reduced saliva flow limits the mouth’s natural ability to neutralise acids and wash away harmful bacteria, allowing imbalance to develop more easily.

Metallic or bitter taste in the mouth

A lingering metallic or bitter taste may result from inflammation or bacterial by-products, often linked to gum irritation or infection.

Frequent sore throats or mouth ulcers

When oral bacteria become imbalanced, they can cause local irritation, leading to recurrent throat inflammation or small painful ulcers in the mouth.

Recurring inflammation or gum pain

Continuous tenderness or gum discomfort reflects a disrupted microbial environment and ongoing immune response within the oral cavity.

Did you know that your oral microbiome is connected to your gut microbiome?

 

The mouth and gut are part of one continuous ecosystem. Microbes that live in the mouth can travel through swallowing and influence gut balance. Similarly, gut inflammation can alter the composition of oral bacteria. Maintaining oral microbial health therefore supports the entire digestive system, from the first bite to nutrient absorption.

The Next Generation of Microbiome Analysis

Shotgun Metagenomics.


We use the most advanced sequencing technology available to study your microbiome in its full complexity. Through Shotgun Metagenomics, every microorganism in your sample is analysed at a genetic level, providing an unparalleled view of your microbial landscape.

This method identifies bacteria, fungi, viruses, and archaea, revealing not only which species are present but what they do and how they interact. By examining functional genes, it uncovers the biological pathways that influence digestion, immunity, and metabolism.

Shotgun Metagenomics is considered the most comprehensive and precise approach for understanding the invisible ecosystems that shape your health.

Differences between Traditional Microbiome Analysis and Shotgun Metagenomics

What Shotgun Metagenomics Data Provides

The Complete Map of Your Oral Ecosystem

Explore every microorganism living in your mouth, including bacteria, fungi, and viruses. See how these microbes form structured biofilms on the tongue, gums, and teeth and how they work together to maintain oral balance and protect against disease.

The Diversity That Defines Your Oral Health

Measure the richness and stability of your oral microbial community. High diversity reflects resilience and supports healthy gums, enamel integrity, and balanced pH, while reduced diversity is linked to inflammation and oral diseases such as periodontitis or caries.

Functional Insights Within the Mouth

Understand what your oral microbes actually do. Identify pathways involved in vitamin production, nitric oxide metabolism, pH regulation, and the breakdown of food molecules. These insights reveal how the microbiome supports oral immunity and protects tissues from oxidative stress.

Illustration of bacteria cells with a blue outline on a white background

Personalised Oral Microbial Profile

Compare your microbial composition with healthy reference models to see where your balance stands. Learn which beneficial bacteria are underrepresented and which opportunistic species may be contributing to inflammation, sensitivity, or bad breath.

Early Signals of Oral Imbalance

Detect subtle microbial changes that occur before symptoms appear. Shifts in species composition can indicate early gum inflammation, enamel erosion, or conditions linked to systemic health such as cardiovascular disease and metabolic inflammation.

From Data to Direction

Transform scientific results into personalised actions. Your report provides tailored recommendations on oral hygiene, nutrition, and probiotic support designed to restore microbial balance and strengthen the connection between your mouth, gut, and overall wellbeing.

Dive deeper in the Longevity Hub

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Stories from Those Who Finally Got Answers

We are grateful to everyone who shared their journey with us. Their honesty reminds us why understanding our biology matters, because behind every test result there is a story of someone finally getting the answers they have been looking for.

I had no major issues, but I did this out of curiosity and ended up learning a lot about how bacteria in the mouth can affect energy and focus. It’s strange how much it connects to everything else. I’ve been more mindful since.
— Chloe S, 33
I always had this weird bad taste in my mouth, even though I brushed all the time. I never thought bacteria could be behind it. The test showed me what was really happening, and after making a few changes, my mouth actually feels fresh again for the first time in years.
— Daniel K, 38
I was dealing with bleeding gums and thought it was just stress. The results made me realise my oral health was linked to other parts of my body too. It made me take my routine seriously, and now my gums don’t bleed at all.
— Aisha N, 27

Explore Our Microbiome Tests

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Oral Microbiome Test

£180.00
Gut Microbiome Test

Gut Microbiome Test

£190.00

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