The connection between the oral microbiome and our health has been established for a long time. And new emerging research reported in an article in The Times talks about the connection between the oral microbiome and breast cancer.
Research has increasingly linked the state of the oral microbiome to several other health outcomes such as; Cardiovascular Disease, Alzheimer’s, Rheumatoid Arthritis, Inflammatory Bowel Disease and Gastrointestinal Disorders and now also cancer.
Recently a journalist from The Times visited a longevity clinic to find out whether the gum infection she had two years earlier was linked to her recent breast cancer. The longevity clinic she visited carried out a whole range of tests (more details below) but with an annual joining fee of £22,000, this is clearly not accessible to everyone.
Read more about our oral microbiome test here
And another two articles in the times What is the oral microbiome and how does it affect your health?
and The secret to oral health: protecting your mouth’s microbiome and discusses how the bacteria in our mouths has been linked Alzheimer’s, type 2 diabetes and even erectile dysfunction.
Does your mouth matter?
The oral microbiome, which consists of trillions of bacteria, fungi, viruses, and other microorganisms found in the mouth, plays a crucial role in maintaining not only oral health but also overall health. The Times article highlighted the importance of the oral microbiome and checking the health and balance of bacteria in the mouth.
Research has increasingly linked the state of the oral microbiome to several health outcomes, such as Cardiovascular Disease, Alzheimer’s, cancer, rheumatoid arthritis, Inflammatory Bowel Disease and gastrointestinal disorders.
The link to the oral microbiome and cancer is interesting as over the last three decades (1990-2019) cancer rates in the under 50 age group have increased by a staggering 79%. And King’s college London have been given £20 million and are trying to solve the conundrum of why this has increased so dramatically.
How Can Such A Small Area Have Such A Big Impact On Our Health?
First it is helpful to understand how the oral microbiome effects our health. Oral pathogens trigger inflammatory responses in a mouth but given our mouth links to our whole body, these inflammatory responses can travel throughout the body via our digestive tract. This in turn can then activate our immune system.
This process progresses quicker if gum disease is present as the pathogens directly enter the bloodstream via the gums. Once in the blood, these pathogens can travel through the body causing potential damage. This inflammation triggers the release of cytokines, these are proteins that cause inflammation.
This can also interfere with insulin, making it harder for it to help cells absorb glucose (sugar) from the blood. When this happens, glucose builds up in the bloodstream instead of being used for energy, which can lead to high blood sugar levels. This situation is common in conditions like insulin resistance and type 2 diabetes.
Oral Microbiome and Breast Cancer – the How and Why?
Studies have started to uncover how the makeup and health of the oral microbiome might influence breast cancer risk, development, and progression.
The bacteria in our mouths play an important role in digestion and immunity. When this balance is disturbed (a condition called dysbiosis), it can cause inflammation, which is known to increase the risk of cancer.
The bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, which are linked to gum disease, have also been connected to inflammation and higher cancer risk elsewhere in the body. This could promote the growth and spread of breast cancer cells. Pathogenic bacteria may produce toxins and metabolites that contribute to growth of cancer cells. Some bacteria produce metabolites that can damage DNA or cause cellular mutations, both of which are risk factors for cancer.
Breast cancer can be an oestrogen dominant cancer, meaning that the cancer cells have receptors that bind to oestrogen. In this case, oestrogen could promote the growth and spread of these cancers. Some oral bacteria can change estrogens into cancer-causing substances, like 4-hydroxyestrone and 16α-hydroxyestrone (16α-OHE), and can also trigger inflammation in the mouth and throughout the body (Tatullo et al, 2024).
Finally, dysbiosis of the oral microbiome leads to an imbalance in the immune system. This can be dangerous as the immune system is the first line of defence and is needed to detect and destroy cancerous cells.
While the connection between the oral microbiome and breast cancer is still under investigation, evidence increasingly suggests that the health of our oral microbiome could play a role in cancer prevention. Ongoing research is needed to clarify these links, understand mechanisms, and evaluate whether modifying the oral microbiome could be a part of breast cancer prevention or management strategies.
Researchers are exploring the possibility of using certain bacteria as biomarkers to help detect breast cancer risk or presence. An altered oral microbiome profile might serve as an early indicator of risk for a number of health conditions. This is a relatively inexpensive test that you can order here: https://smartnutrition.co.uk/shop/oral-ecologix-oral-microbiome-check/
Oral Microbiome and Head and Neck Cancer
An article that has been published this week in the New Scientist (Geddes, 18.11.2024) presented new data that links the oral microbiome with head and neck cancers which have risen by 35% in the UK since the early 1990s. These cancers can originate in over 30 locations, such as the mouth, throat, sinuses, and salivary glands.
Typically, this has been an area where research has focused on smaller studies, making it difficult to link whether the bacteria actively contributed to cancer development or were simply present as a result of the disease. However, in September, a study led by Soyoung Kwak at the New York University Grossman School of Medicine offered new insights. The team analysed data from three large, ongoing US studies tracking the health of 159,840 participants. Saliva samples collected at the studies’ start were later compared to the development of head and neck squamous cell carcinoma—a cancer affecting the mucous membranes of the mouth, nose, and throat—10 to 15 years later. The analysis revealed a correlation between this cancer and the presence of up to 13 bacterial species in the original saliva samples, many of which had not been previously associated with the condition.
The researchers also found a moderate association between cancer risk and “orange and red complex” bacteria, known for their strong link to gum disease. Together, these bacterial groups were significantly associated with an increased risk of developing head and neck cancer. Although the study did not prove a causal relationship, it provided some of the strongest evidence to date that specific bacteria may play a role in cancer development.
Recent research from Reis Ferreira’s at King’s College London, adds complexity to the relationship between Fusobacterium nucleatum, part of the red complex bacteria, and cancer. They found this to have a positive effect on cancer cells by reducing their viability. Commenting on Kwak’s research, he commented the associated could be “coincidental, as these bacteria thrive in inflamed environments, and inflammation itself is a well-known risk factor for cancer”.
Oral Microbiome and The Link With Chronic Disease
Let’s now have a look at some of the other diseases mentioned above and the link with the Oral Microbiome:
Cardiovascular Disease
The link between oral health and cardiovascular disease is well-established. Pathogens commonly found alongside gum disease, particularly P. gingivalis, can enter the bloodstream through inflamed gums and reach the heart and blood vessels. This bacterial movement, can trigger inflammation in blood vessels, contributing to atherosclerosis (plaque buildup in the arteries), which is a key risk factor for heart attack and stroke. Systemic, across the body, inflammation caused by oral bacteria may also lead to an increase in C-reactive protein (CRP), a marker associated with higher cardiovascular disease risk.
Diabetes
The relationship between diabetes and the oral microbiome is bidirectional. People with diabetes are more prone to gum disease due to poor immune function and high blood glucose levels, which promote bacterial growth in the mouth. Conversely, chronic periodontal disease can worsen blood sugar control in diabetes. The inflammation caused by periodontal bacteria can increase insulin resistance, complicating blood sugar management. This interplay suggests that managing oral health may play a role in improving metabolic health in diabetes patients.
Gastrointestinal Disorders
The oral microbiome is the first part of the digestive system and helps shape gut bacteria. An imbalance in oral bacteria can contribute to gut diseases like inflammatory bowel disease (IBD) and colorectal cancer. Harmful oral bacteria, when swallowed, can upset gut bacteria and trigger inflammation in the intestines, leading to issues like Crohn’s disease, ulcerative colitis, and even colorectal cancer.
Alzheimer’s Disease and Cognitive Decline
Evidence is growing that gum bacteria like P. gingivalis may be linked to Alzheimer’s disease. These bacteria can reach the brain through the bloodstream or by infecting immune cells, where they may cause inflammation and contribute to brain cell damage. Chronic inflammation from these oral bacteria may also lead to the buildup of beta-amyloid plaques, a key feature of Alzheimer’s. This suggests that good oral health could help lower the risk of cognitive decline.
Rheumatoid Arthritis
Studies suggest a strong link between periodontal disease and rheumatoid arthritis (RA). P. gingivalis, a key player in periodontal disease, produces enzymes that may exacerbate RA by promoting the formation of proteins involved in autoimmune responses. This bacterial influence on immune function can lead to increased inflammation and joint damage in RA patients.
Respiratory Infections
Oral bacteria can quickly travel into the lungs, leading to infections such as pneumonia, especially in older adults or immunocompromised individuals. Streptococcus pneumoniae and Pseudomonas aeruginosa, among others, are implicated in these respiratory infections. These infections have been known to worsen conditions like chronic obstructive pulmonary disease (COPD) and pneumonia.
In conclusion, maintaining a balanced oral microbiome and good oral hygiene is vital not only for oral health but for overall systemic health. The connection between the oral microbiome and various diseases highlights the importance of oral health in preventing and potentially managing chronic diseases.
Tests that are mentioned in The Times article can be purchased directly via the links below, without a hefty membership fee needed:
H.pylori can be added to most of the stool tests which you can find here or completed as a stand alone helicobacter pylori test
Finally, if you are concerned about your health but unsure where to start, then we do have a team of fully qualified Functional Medicine Nutritional Therapists who can help you. Feel free to book a discovery call with one of the team: