Oral Microbiome and Cardiometabolic Conditions

A well-established link has been documented between periodontal disease and cardiometabolic conditions such as metabolic syndrome¹ as well as cardiovascular diseases (CVDs) like atherosclerosis, heart disease, and acute coronary events, including myocardial infarction.^2,3 The chronic inflammation and oral microbiome dysbiosis associated with periodontal disease may contribute to cardiometabolic conditions due to mechanisms such as the chronic dissemination of pathogenic bacteria into circulation that triggers systemic inflammatory responses.^3,4 As an example, a study in 2019 showed—for the first time—the common presence of oral bacterial DNA from viridans streptococci in aspirated thrombi of patients with acute ischemic stroke.⁵

Updated evidence continues to suggest that oral health and systemic disease are indeed linked—what’s healthy for the mouth is also healthy for the rest of the body, and vice versa.^6,7

Oral Microbiome: Cardiometabolic Health & Mechanisms

A 2024 umbrella review of 41 systematic reviews continued to affirm a significant association between periodontal disease and CVD and suggested dysbiotic oral bacteria and systemic inflammatory responses as primary mechanisms.³ In addition, studies continue to suggest that infections in the oral cavity and periodontal bacteria may be contributing factors to inflammatory and cardiometabolic diseases.^8,9

There are approximately 1,000 species of bacteria in the oral cavity, and a variety of factors may alter the balance and composition of oral microbial communities, leading to dysbiosis.¹⁰ In addition to oral bacterial translocation into the blood stream and systemic inflammation, studies continue to clarify other potential mechanisms through which oral microbiota dysbiosis influences cardiometabolic health, including immune responses, cytokine release, and modification of the gut microbiota.^4,11

The oral-gut axis continues to be explored and clarified as a potential mechanism of pathogenic bacteria associated with an increased risk of systemic inflammation and cardiometabolic conditions.¹¹ The migration of these microbes from the oral cavity to the gastrointestinal tract through the oral-gut barrier may induce changes to gut microbiota composition, intestinal barrier integrity, and immune system function.¹¹ In addition, pathogenic bacteria in the oral cavity may produce harmful metabolites that infiltrate the bloodstream and overall system.⁴ For example, trimethylamine N-oxide (TMAO), known for its detrimental impact on cardiovascular health, is primarily produced by gut microbes. However, emerging research suggests that pathogenic oral bacteria can also produce this metabolite, further linking oral dysbiosis to cardiovascular disease risk.⁴

Clinical Evaluations & Healthy Oral Hygiene

Oral examinations of patients may reveal signs and symptoms of systemic disease; however, the mouth exam may be overlooked during routine clinical evaluations. Comprehensive assessment exams, as taught in functional medicine, are tools that may help detect imbalances and early warning signs of disease. Oral examinations could help clinicians not only recognize poor oral health but also detect clues to seemingly unrelated health issues.

The functional medicine model recognizes that everything in the body is connected, and oral health is important for overall health. A 2024 systematic review investigated the association between oral hygiene practices in reducing cardiometabolic risk and mortality and found that among adults, daily toothbrushing and interdental cleaning (e.g., flossing) lowered the risk of developing type 2 diabetes or hypertension.¹² In addition, these two daily practices were associated with a decrease in CVD mortality compared to brushing alone.¹² Establishing a collaborative therapeutic relationship with patients is vital to educate and empower patients with practical lifestyle-based approaches to health such as good oral hygiene.

Learn more about how personalized lifestyle approaches may address a patient’s cardiometabolic concerns at IFM’s upcoming Cardiometabolic Functional Medicine Advanced Practice Module® (APM).