How Treating Dental Infections May Improve Whole-Body Health

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Fixing dental infections does more than relieve pain — it may support heart and metabolic health, according to research published in the Journal of Translational Medicine.

“Long-standing root canal infections can allow bacteria to enter the bloodstream, trigger inflammation and increase blood glucose and fats levels — raising the risk of serious health issues like heart disease and diabetes,” explained lead investigator Sadia Niazi, Ph.D., M.Sc., B.D.S., senior clinical lecturer in endodontology at King’s College London. “It is vital that dental professionals recognize the wider impact of these root canal infections and advocate for early diagnosis and treatment.”

Apical periodontitis (AP) is a common dental infection that develops when bacteria enter the root of a tooth and cause inflammation. While most people think of AP as a dental issue, research increasingly shows that this kind of chronic infection can affect the whole body. It may raise overall inflammation, worsen blood sugar control, and even increase the risk of heart and metabolic diseases.

This new two-year study followed 65 people with AP to find out whether treating the infection through successful root canal therapy could improve overall health — not just oral health. Investigators analyzed blood samples at five points in time (before treatment and then at three months, six months, one year and two years) using a technology called NMR spectroscopy. This allowed them to measure tiny molecules in the blood called metabolites, which help show how the body is processing sugars, fats and inflammation.

The results were encouraging. After root canal treatment, more than half of the measured metabolites (24 total, 54.5%) changed in ways that signal better metabolic and inflammatory health. Early improvements were seen by three months, including a drop in branched-chain amino acids — markers linked to insulin resistance. Over two years, patients also showed lower glucose and pyruvate levels, suggesting better blood sugar metabolism. Short-term drops in cholesterol, fatty acids and choline pointed toward healthier lipid processing. At the same time, tryptophan levels increased steadily, which is often associated with reduced inflammation.

The study also found that these metabolic changes were strongly linked with markers of metabolic syndrome, inflammation and even the bacteria found in patients’ blood and infected tooth canals before treatment. This highlights that oral infections don’t stay in the mouth — they influence the whole body.

Using advanced modeling, the team of investigators discovered that certain metabolites related to the body’s energy-producing tricarboxylic acid cycle played a leading role in these improvements over time.

“Our findings show that root canal treatment doesn’t just improve oral health — it may also help reduce the risk of serious health conditions like diabetes and heart disease,” said Niazi. “It’s a powerful reminder that oral health is deeply connected to overall health.”

Taking care of serious dental infections may help reduce long-term cardiometabolic disease risks, making oral health an important part of whole-body health.

The team cautioned that these results should be interpreted carefully. The study included a small number of patients, which makes it harder to draw firm conclusions. Because there was no comparison group of people without AP or people whose root canal treatment did not succeed, the study could not determine how patients’ starting metabolic profiles differ from those of healthy individuals, or how metabolism changes when treatment fails. They also note that other lifestyle factors, such as diet, may have influenced the results and were not fully measured.

Larger studies that include healthy comparison groups and unsuccessful treatment cases are needed to better understand how AP and its treatment affect the body’s metabolism over time.

“We also need to move toward integrated care, where dentists and general practitioners work together to monitor the risks through these blood markers and protect overall health,” concluded Niazi. “It’s time to move beyond the tooth and embrace a truly holistic approach to dental care.”