Our oral health may be more connected to heart health than we once thought.
The bacterium Fusobacterium nucleatum (F.nucleatum) is known for causing gum disease and bad breath. Now, it’s also being linked to heart disease and impacts our cardiovascular health.
Studies show that infection with this bacterium can increase systemic inflammation when it spreads from the gums and enters the bloodstream, triggering inflammation and potentially damaging blood vessels.
It might even directly colonize the walls of arteries, contributing to plaque buildup. Plaque buildup in arteries restricts blood flow to the heart, increasing the risk of heart attacks and other cardiovascular diseases.
Globally, heart disease is the leading cause of death, according to the World Health Organization (WHO). While genetics heavily influences cardiovascular risk, other lifestyle factors like oral health may also play a key role.
Early detection and treatment of F. nucleatum infections could reduce cardiovascular events. Here’s how this bacteria may affect your heart and what you can take to lower your risk.
Fusobacteria are bacteria often found in the mouth, gut, and female reproductive tract. The most common species of this bacteria in humans are Fusobacterium nucleatum and Fusobacterium necrophorum.
Fusobacterium nucleatum can lead to chronic inflammation, which is linked to systemic health issues such as cardiovascular disease.
F. nucleatum is one of the most common bacteria found in the mouth. Initially, this bacteria was considered harmless but was later linked to gum disease or periodontal infection. Studies found that its presence drastically—up to 10,000 times—in infected areas.
The presence of F. nucleatum is linked to various gum diseases (periodontitis), from mild gingivitis to more severe forms like chronic periodontitis. This bacterium can also cause endodontic infections (affecting the inside of a tooth and surrounding gum tissue), such as pulp necrosis.
F. nucleatum is often found in higher levels in people with gum disease, and its presence is linked to the severity of the condition. Environmental factors, like smoking and uncontrolled diabetes, can also boost the level of bacterial infection.
Animal studies show that F. nucleatum can lead to significant periodontal infections, causing bone loss and abscesses, especially when it works together with other harmful oral bacteria.
Recent findings also suggest that F. nucleatum may act as a bridge between gum disease and atherosclerosis.
In 1983, doctors recorded the first case of F. nucleatum causing pericarditis, an inflammation of the heart’s lining. However, it’s only in recent years that science has begun to understand how this oral bacterium may contribute to atherosclerosis, a serious condition where plaque builds up in the arteries.
Studies have shown that patients with periodontal disease are at a higher risk of developing coronary artery disease, with differences noted between sexes and statistical analyses highlighting the associated risks.
F.nucleatum impacts the heart by:
F. nucleatum can trigger strong inflammatory responses in the body when the bacterium enters the bloodstream. It prompts immune cells called macrophages to become activated and adopt a pro-inflammatory state known as M1 polarization.
This change causes more foam cells—fat-filled cells that build up in artery plaques—which weaken the plaques and increases the risk of dangerous blockages.
Additionally, mice infected with F. nucleatum showed higher levels of proinflammatory cytokines. These cytokines in the plaque area may also help trigger the development of atherosclerosis.
F. nucleatum also affects how the body processes fats and cholesterol. It has been shown to reduce levels of high-density lipoprotein (HDL), which is considered “good” cholesterol, while increasing levels of oxidized low-density lipoprotein (ox-LDL), a harmful form of cholesterol associated with heart disease.
This imbalance may accelerate atherosclerosis development and promote plaque buildup in arteries.
MicroRNAs (miRNAs) are tiny RNA molecules that don’t code for proteins but help control how genes work. They’re about 20-25 nucleotides long and bind to messenger RNA (mRNA). This either blocks the mRNA from making proteins or breaks it down. miRNAs can also help start protein production or influence how genes are read.
Recent studies identified miRNAs influenced by F. nucleatum play a role in regulating inflammation and cholesterol metabolism. Increased levels of microRNAs like miR-146a and miR-155 have been linked to higher plaque areas in arteries and may help explain how F. nucleatum contributes to heart disease.
F. nucleatum can be seen outside the oral cavity and can affect a wide range of organs, including bones, lungs, joints, blood, abdomen, and pelvis.
F. nucleatum is now classified as an opportunistic pathogen. An opportunistic pathogen may not cause an infection in healthy individuals but does so when faced with a weakened immune system.
Diseases Linked to F.nucleatum include:
People with gum disease are more likely to experience a heart attack, stroke, or other cardiovascular issues.
Preventing gum disease through proper dental hygiene may reduce the risk of heart disease, highlighting the importance of regular dental checkups and early treatment of any gum issues for overall health improvement.
So, practicing good dental hygiene can help:
In addition to these tips, the American Heart Association offers a checklist that recommends ways to improve and maintain heart health.
It’s important to note that not everyone with heart disease has gum disease. The reverse is also true— a gum infection does not automatically signify cardiovascular disease.
Although F. nucleatum is found mainly in the oral cavity, it is linked not only to gum disease but also to serious health issues like heart disease. This bacterium’s ability to move from the mouth to other parts of the body shows how poor oral hygiene can have far-reaching effects beyond just your teeth and gums.
Research continues to uncover these connections and underlines the importance of maintaining good oral health in order to prevent various diseases and stay healthy overall.
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Learn about more bacterial infections on the GIDEON platform.
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