When you think about bacteria in your mouth, plaque and cavities are often the first things that come to mind. However, ongoing research has uncovered the role of certain oral bacteria in not just oral health but also broader health concerns. One bacterium in particular, Fusobacterium nucleatum, has been linked to conditions beyond gum disease, including potential associations with cancer and pregnancy complications.^1,2 Here’s what the latest research tells us about Fusobacterium nucleatum, its potential health impacts, and steps you can take to maintain a healthy oral environment.

What is Fusobacterium nucleatum?

Fusobacterium nucleatum is a common bacterium that resides in the spaces between the teeth and gums. While it is naturally present in the oral microbiome, research has shown that under certain conditions, F. nucleatum can contribute to inflammation and play a role in various health conditions.³

Recent studies have focused on the relationship between oral health and overall health, revealing that bacteria like F. nucleatum may have broader effects when they travel beyond the mouth.

Key Health Concerns Linked to F. nucleatum

1. Potential Link to Cancer
   Some of the most intriguing research surrounding F. nucleatum is its association with colorectal cancer. A number of studies suggest that the presence of high levels of this bacterium in the digestive tract may be linked to a greater likelihood of developing colorectal tumours.^1,4
   
   The proposed mechanism is that F. nucleatum may promote tumour growth by triggering inflammatory responses and interfering with the body’s immune system, making it harder for the body to identify and attack cancer cells. While these findings are still being explored, they highlight the importance of understanding how oral bacteria can influence health beyond the mouth.
   
   
2. Pregnancy Outcomes
   Another area of interest is the potential connection between F. nucleatum and pregnancy outcomes. Research suggests that this bacterium may contribute to pregnancy complications such as premature birth and low birth weight.^2,5
   
   One study found that oral bacteria can sometimes enter the bloodstream, particularly in cases of gum disease, and reach the placenta, where they may trigger inflammation. Inflammation during pregnancy has been linked to early labour and other complications, though more research is needed to fully understand the mechanisms involved.

Practical Steps to Support Oral Health and Reduce F. nucleatum

Given the emerging research on F. nucleatum, maintaining a balanced oral microbiome is important. There are several evidence-based strategies that can help reduce harmful bacteria and promote oral health.

1. Xylitol-Based Toothpaste and Gum
   Xylitol, a natural sugar alcohol, has been shown to reduce levels of harmful bacteria in the mouth, including F. nucleatum. Xylitol works by preventing bacteria from feeding on sugars and thriving, making it a useful addition to your oral care routine. Interestingly, a study conducted in Malawi demonstrated that pregnant women who used xylitol chewing gum twice a day had fewer incidents of premature birth, suggesting additional benefits for maternal health.⁶ Many natural toothpastes, like Gutology, are formulated with xylitol in conjunction with hydroxyapatite.
   
   
2. Consistent Oral Hygiene Practices
   Practicing regular brushing and flossing is one of the most effective ways to manage oral bacteria. Research indicates that removing plaque and food debris is key to preventing F. nucleatum and other bacteria from accumulating and contributing to oral and systemic inflammation. Aim to brush for at least two minutes twice a day and floss daily.⁷
   
   
3. Limit Sugary Foods
   Research has long demonstrated that sugar consumption promotes the growth of harmful bacteria in the mouth. Reducing sugar intake, alongside maintaining a diet rich in fibre, healthy fats, and plenty of water, can help keep the oral microbiome in balance and support overall health.⁸

A Research-Driven Approach to Oral Health

A growing body of research underscores the importance of oral health as part of a holistic approach to well-being. From a functional medicine perspective, oral bacteria like F. nucleatum may play a role in systemic health conditions. Supporting both oral and gut health, reducing systemic inflammation, and maintaining strong oral hygiene habits can help minimise the risks associated with bacterial imbalances.

While F. nucleatum is naturally present in the mouth, these findings suggest that keeping its levels in check is important. The research continues to evolve, but it highlights the interconnectedness between the oral microbiome and broader health outcomes.

Conclusion

Although F. nucleatum may be a common resident of the mouth, research suggests that its effects extend far beyond the gums. By following evidence-based oral care practices - such as using xylitol-based products, practicing consistent hygiene, and limiting sugar intake - you can help manage the levels of this bacterium and support both your oral and overall health.

As science continues to uncover the links between oral bacteria and systemic conditions, maintaining a healthy oral microbiome remains a key part of overall wellness.