Heart attacks and strokes are preventable. One of the root causes of heart disease that dentists and doctors aren’t talking about enough is bad bacteria that cause gum and mouth infections. These bad bacteria have a direct line to the heart, sparking inflammation and damaging blood vessels. They have been found in atherosclerotic plaques after heart attack or stroke. Unfortunately, these bad bacteria are all too common, affecting almost half of adults over the age of 30 with gum disease. Since heart disease is the number one cause of death and disability in the US, we cannot afford to overlook bad oral bacteria. If you have bleeding gums, swollen gums, or painful chewing you could be sending bad bacteria coursing through your veins and causing heart problems. Even after a heart attack, you can still turn the ship around by targeting your oral health. Clinicians, dentists, and consumers need to know how to address these infections and restore the oral microbiome. Find a competent oral-systemic dentist, test the oral microbiome, get rid of bad mouth infections, and build up your good bacteria for a healthy mouth and cardiovascular system that will keep going for many years to come!

 

We are grateful to our sponsor, OralDNA Labs, for making this blog possible.

 

 

If you have gum disease, your risk for heart attack is nearly 50% higher.¹

There’s no debate about it. Heart disease has a source in the mouth. Evidence showing your dental health is linked to your heart health has been stacking up for decades:

• Oral bacteria have been found in atherosclerotic plaques²
• Oral bacteria can lower blood pressure
• Flossing and brushing decreases your risk of heart disease, heart attacks, and stroke^3,4
• Flossing and brushing decreases your levels of inflammation, especially CRP (a powerful marker of heart disease and inflammation)⁵

 

Poor Oral Health and Heart Disease

Gum disease affects 42% of adults over the age of 30. And nearly half of all adults in the US have heart disease. That’s practically everybody!

Heart disease is the number one cause of death in the United States. When fatty deposits, or plaque, build up on the inner walls of arteries, it causes the “pipes” that move your blood to get stiff and narrow. This process is known as atherosclerosis. Inflammation is a key factor that drives this disease. Blood has a harder time moving through the pipes, which causes high blood pressure. If blood can’t reach the heart easily, then heart cells die (heart attack) and the heart can’t pump blood effectively. And if plaque builds up heavily or gets dislodged, it can block blood flow completely. We can experience that as chest pain, a heart attack, or a stroke.

Gum disease isn’t pretty either. When bad bacteria take over in the mouth and trigger an immune attack, it causes gum disease. These harmful bacteria make toxins, sparking inflammation, and your immune system goes on the rampage, destroying gums and bones. It might show up as mild bleeding gums or cause your teeth to loosen and fall out.

Warning signs of gum disease (or periodontal disease):

• Tender or bleeding gums
• Red or swollen gums
• Bad breath or bad taste that won’t go away
• Painful chewing
• Loose teeth
• Receding gums

Mouth Infections Can Trigger Heart Attack or Stroke

It’s well-established that certain pathogenic mouth bacteria contribute to heart disease. People with gum disease have up to a 20% increase in their risk of coronary vascular disease.^1,6 The following specific oral bacteria are contributors to heart disease, especially when they are working together (known as co-infections) in the mouth.^2,7-10 They can leak from blood vessels in the gums and travel to the heart and cardiovascular system.^2,11 These bacteria can set off an immune response,¹² inflammation in arteries,⁹ and contribute to buildup of atherosclerotic plaques that can rupture and block  vessels, potentially causing a heart attack or stroke.¹⁰

Think of a bad bacteria in the mouth as an infection that spreads like fire throughout your cardiovascular system. This infection can create inflammation in your veins and arteries. It can injure the lining of your veins and arteries. When your blood vessels get little nicks and scrapes on them, it can lead to a plaque, much like a scab on your skin. As you know, plaque can cause trouble for the heart and brain when it gets loosened up and travels through the bloodstream where it doesn’t belong. Loosened up plaque can block the flow of blood and lead to heart attack or stroke.

For dentists and clinicians trying to prevent or reduce heart disease, a major goal of treatment should be to minimize the levels of these bacteria as much as possible.¹⁰ If you have heart disease and your doctor and dentist have not mentioned these mouth infections, then they are not informed and you need to look for a new healthcare team.

As we review these bacteria, keep in mind that human bacteria are divided into three major categories.

• Commensal– these normal bacteria harmlessly coexist with us and often provide us with health benefits.
• Opportunist– these common microbes may not cause problems. On the other hand, they can overgrow and cause disease when the circumstances are right, such as when you have a weakened immune system or disturbed microbiome.
• Pathogen– causes disease.

These are important distinctions within the oral microbiome, as I explain later in the section, “Not All Bugs Are Bad Bugs.”

 

Porphyromonas gingivalis 

Porphyromonas gingivalis is considered a pathogenic bacterium. It is a primary cause of gum disease, especially the severe forms, and belongs to the “red complex” of periodontal pathogens, along with Tannerella forsythia and Treponema denticola. P. gingivalis particularly likes periodontal pockets where it can thrive, produce virulence factors (toxins), and destroy gum tissue and bone. P. gingivalis can spark a cascade of inflammatory chemicals¹³ and it can increase adhesion factors and attract macrophages, which contribute to plaque buildup in the lining of vessels.¹⁴ Indeed, it has also been found in atherosclerotic plaques.¹⁵ Gingipains, which are enzymes from P. gingivalis, have been found in atherosclerotic plaques and directly damage the arterial lining, contributing to heart disease. P. gingivalis, its virulence factors, and inflammatory chemicals can spread from the mouth to the heart through the bloodstream. Higher levels of P. gingivalis increased the risk for acute coronary syndrome¹² and for sleep apnea with cardiovascular disease .¹⁶ It has also been implicated in stroke,¹⁷ rheumatoid arthritis, Alzheimer’s disease, respiratory infections, and pregnancy complications. Even though P. gingivalis is a pathogen, it can exist in the mouth in some people without causing harm.

 

Tannerella forsythia

Tannerella forsythia is part of the “red complex” of bacteria strongly related to advanced gum disease. It is generally considered a pathogen due to its major role in oral inflammation and tissue destruction. T. forsythia produces methylglyoxate, a toxic and inflammatory chemical that breaks down tissues in the mouth.¹⁸ T. forsythia can contribute to atherosclerosis by triggering inflammation and damaging the cells lining the arteries, which encourages plaque development. It has been found in samples from blocked arteries.¹⁹ One study showed increased levels of inflammation in the heart and accelerated atherosclerosis when mice had T. forsythia infection.²⁰ Higher immune responses to T. forsythia in the mouth increased the chances of acute coronary syndrome.^12,21

 

Treponema denticola

Treponema denticola is a “red complex” mouth bacteria, a key player in aggressive gum disease, and is generally considered a pathogen. T. denticola evades the immune system and creates virulence factors that cause damage and disease. It has been associated with atherosclerosis and found in blocked arteries.^19,22 It has been implicated in heart disease through its role in gum disease and the systemic inflammation it creates, damaging the walls of the arteries. Higher immune responses to T. denticola were found in ischemic stroke patients with poor outcomes.¹⁷

 

Aggregatibacter actinomycetemcomitans

Aggregatibacter actinomycetemcomitans is a commensal mouth bacteria meaning it can exist  harmlessly in the mouth. However, it can overgrow and cause disease in the mouth, making it an opportunistic pathogen. It is infamous for its causative role in gum disease.²³ It can contribute to inflammation of blood vessels.¹¹ A. actinomycetemcomitans has been detected in atherosclerotic plaques, suggesting its role in plaque formation and progression.²⁴ It is more common in people who have suffered a stroke.²⁵ People with gum disease who have a higher immune response to A. actinomycetemcomitans show an increased risk of acute coronary syndrome¹² and an increased risk of stroke.¹⁷ Its role in heart disease may include invasion of tissues, affecting platelet aggregation, immune response, inflammation, and oxidative stress.  A. actinomycetemcomitans can also infect heart valves, soft tissue, brain, lungs, and distal bones.²⁶

 

Fusobacterium nucleatum

Fusobacterium nucleatum is a normal member of the human oral microbiome and can have a symbiotic relationship with us. On the other hand, it has long been known to cause opportunistic infections. F. nucleatum is involved in gum disease and sparks inflammation in the mouth, working together with other gum-disease-causing microbes. F. nucleatum has been associated with coronary heart disease,²⁷ and has been found in atherosclerotic plaques.²⁸ It produces several virulence factors that cause inflammation in the arterial lining.^12,27 It also can cause the arterial cell lining to be weak and porous, as well as release chemicals that make the lining sticky and prone to plaque buildup.²⁸ Higher immune responses to F. nucleatum can be seen in acute coronary syndrome^12,28 and in stroke patients.¹⁷ F. nucleatum has a track record of causing other trouble outside of the mouth, too, including: colorectal cancer, appendicitis, brain abscess, bone infection, swelling and irritation of the tissue around the heart, rheumatoid arthritis, and adverse pregnancy outcomes.^27,29

 

Prevotella intermedia 

Prevotella intermedia is considered an opportunistic pathogen. While it can exist in the mouth without causing disease, it also can overgrow and cause gum disease and gingivitis under the right circumstances. P. intermedia has been found in atherosclerotic plaques¹⁵ and can contribute to atherosclerosis by triggering inflammation and plaque buildup. P. intermedia can produce enzymes that break down the arterial wall lining, making them more susceptible to plaque formation. People who have P. intermedia bacteria in the mouth have a higher risk of atherosclerosis than those who do not.^19,24,30 Higher mouth bacteria levels of P. intermedia, together with higher immune responses to it, increases the risk of acute coronary syndrome¹² and stroke.¹⁷ It has also been identified as a problem bacteria for people with sleep apnea and cardiovascular disease.¹⁶

Not All Bugs Are Bad Bugs

This blog is about six sinister mouth infections that can hurt the heart. However, these microbes are just a tiny sliver of your whole oral microbiome. The overwhelming majority of bacteria in your mouth are friendly bacteria. If you’ve read my book or other blogs, you know that this is a critical message I want to share with you and others.

Maybe you’ve heard, “bacteria cause cavities,” “gum disease is caused by bad bacteria,” or “bacterial infections cause disease.” Makes you want to get rid of all of your bacteria so you can be healthy, right? Wrong. Despite all of the badmouthing we have heard about bacteria over the years- the majority of our bacteria do good things for us. The way we thought about bacteria over the past century was too narrow-minded. We were blaming all of our woes on specific bad bacteria that had been matched to a certain disease. The solution? Clinicians and dentists wanted us to kill all of those bad bacteria. Antibiotics were passed out liberally to kill infections and they wiped out good bacteria in the process. But the explosion in scientific research on the microbiome over the past few decades tells us we were all wrong. Unfortunately, we may have done permanent damage to our microbiomes in the process.³¹

 

Can Your Oral Microbes Heal Your Heart?

The good bacteria in your mouth balance the pH, fight cavities, lower your blood pressure, resist gum disease, ward off bad breath, calm down inflammation, and tune up your immune system. They create a biological defense against bad pathogenic bacteria. Imagine your mouth is a parking lot.* When good bacteria are filling up all of the parking spaces in the lot, bad bacteria cannot move in and take hold. But if some of the parking spaces are empty, it’s a perfect spot for bad bacteria to move in and set up shop. Their goal is to reproduce, create toxins, do damage, and stay at the top of the heap. The problem is when certain bad bacterial pathogens take over. They can squash the good bacteria. They can make toxic chemicals that kill good bacteria and help them take over. They invite their other bad guy friends to join the party. There is a scientific name for this: “colonization resistance.” By being colonized by many friendly bacteria, you can effectively fight off (or crowd out) disease-causing bacteria .^32,33

In the case of a bacterial imbalance, or “dysbiosis,” with one or more of the six bad bacteria we talk about here, antimicrobials or antibiotics may indeed be needed. They will lower the levels of harmful mouth bacteria. But this is a short-term solution.

The best long-term defense against harmful mouth infections is high levels of friendly bacteria that lock them out. This is why testing is so important.

 

Prevent Heart Attacks and Stroke with Oral Microbiome Testing

Oral microbiome testing helps dentists and clinicians see the microbes in the mouth. They can pinpoint the pathogens that can cause heart disease. They can also pinpoint beneficial bacteria that promote heart health. With testing, clinicians and dentists can monitor changes to the microbes in the mouth to see if treatments are working.

Testing for oral pathogens could be one of the most important things that you or your loved ones do to prevent a stroke or heart attack.

There are many oral microbiome tests for pathogens, such as the PerioPath test from OralDNA Labs. There are also oral microbiome tests that measure friendly bacteria. These tests usually require a simple and convenient oral rinse specimen.

 

Find an Experienced Dentist in the Oral Health and Heart Disease Connection

IMPORTANT! If you have heart disease, getting invasive dental work by a non-expert could put you at risk for a heart attack or stroke. An oral-systemic dentist is a type of dentist who recognizes the well-documented connections between gum disease and heart disease. They know how to test for the mouth infections we talk about here and treat them so that your cardiovascular system can heal. It is unsafe to work with standard dentists who have no special training in this area if you have heart disease and gum disease. They don’t usually test for bad bacteria and are essentially flying blind when treating your mouth. The problem is that it impacts your cardiovascular system, too. Look for dentists who use oral microbiome tests and who can collaborate with your medical doctor. Find doctors who understand the oral-systemic link and who measure your C-reactive protein (hs-CRP) levels, a key biomarker of systemic inflammation.³⁴

 

 

 

Reduce Your Heart Disease Risk with These Oral Health Steps

 

When your mouth bacteria are contributing to heart disease, the main action items are to test the oral microbiome, get rid of bad bacteria, and build up good bacteria. Follow these tips to grow friendly bacteria, chase off the bad bacteria, and cool off the inflammation in the cardiovascular system. These recommendations are in addition to exercise and lifestyle recommendations for reversing heart disease. It’s never too late to boost your oral and heart health, even if you already have had a heart attack or stroke. Improvements to your heart health can happen lightning fast when you address your oral health.

 Get Rid of Bad Mouth Infections

• Choose an anti-inflammatory, whole-food diet with plenty of colorful vegetables and fruits, greens, lean protein, nuts and seeds, and fiber. What you eat all day and everyday has a tremendous effect on the microbes in your mouth. Avoid sugar, refined carbohydrates, and packaged foods which promote unhealthy oral bacteria. The fiber and prebiotics from this diet will feed good bacteria.
• Test the oral microbiome with OralDNALabs’ PerioPath. It measures 11 periodontal pathogens with a simple saliva test and can help your dentist or periodontist pinpoint which bad mouth bacteria might be contributing to heart disease.
• Test hs-CRP to find out your systemic inflammation. A high level indicates risk of inflammation, heart disease, and gum infections.
• Find a dentist who understands and treats the oral-systemic link using this directory of oral-systemic dental practitioners by the American Academy of Oral-Systemic Health (AAOSH).
• Antimicrobials or antibiotics may be needed at the direction of a dentist to reduce bacterial infections in the mouth. These should be used with caution as they can further imbalance the good bacteria.
• Dental hygiene is critical for keeping the oral microbiome balanced. Brushing twice daily, flossing, and visiting your dentist for regular cleanings help to keep mouth bacteria healthy and catch bad bacteria and gum infections early.
• Periodontal treatments such as scaling and root planning may be needed to remove bacteria above and below the gum line and in periodontal pockets. It clears out bacterial overgrowth so that the gums can heal and it reduces the number of bad bacteria flowing to the heart through the bloodstream.
• After you get heart-disease-causing bacteria out of the mouth, check out my recommendations to heal leaky gums by reducing inflammation and repairing the gum tissues.

Build up the Good Bacteria

• Dental probiotics reduce bad oral bacteria. They encourage good bacteria and crowd out the bad. Dental probiotics prevent bacteria that cause mouth and gum infections from coming back.
• Prebiotics from the whole foods diet described above will feed good bacteria so they can fight against mouth infections. These prebiotic foods serve double duty to boost oral health and lower blood pressure: celery, beets, fennel, lettuce, spinach, and parsley.

 

Address Oral Health to Prevent Heart Attacks, Strokes, and High Blood Pressure

When you ask most people, “What can you do to treat heart disease?” they will say diet and exercise. But how many people mention mouth bacteria at the top of the list for turning around heart disease? Even medical doctors rarely mention this as a top contributor to heart disease. While diet and exercise are critical, don’t overlook the sinister bacteria lurking in the mouth that cause gum infections and send the heart into a downward spiral. We reviewed the six mouth infections that harm your heart and the droves of research to back it up. Even after a heart attack, it isn’t too late to turn the ship around. Everyone should be talking about this, including medical practitioners, dentists, and consumers. Addressing oral health should be a fundamental component of a heart health program. Work with your oral health team to tackle the sinister six pathogens, run oral pathogen testing, get the right kind of doctors and dentists on your team, and take steps with your home care to turn around gum disease and heart disease with a one-two punch.

 

OralDNA® Labs is breaking barriers through innovation and a mission to help healthcare providers treat, heal, and inspire oral and overall health through salivary diagnostics. They are widely known for MyPerioPath® – which identifies 11 oral pathogens known to threaten oral and systemic health.  Their menu offers options ranging from bacterial and viral analysis to the identification of genetic inflammatory markers – all from one simple 30-second oral rinse collection. When you sign up to become an OralDNA® provider, you benefit from years of experience and knowledge, and can rely on the services and support you need to deliver the best patient care possible. Get started TODAY!

 

*The parking lot analogy comes from my functional nutritionist colleague, Robin Nielsen.

 

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