There has been a significant and alarming rise in heart attack cases, particularly among young adults and people under 40, across the globe and in India. Heart attacks have long been linked to cholesterol buildup, poor diet, smoking and hypertension. But a new study suggests that oral bacteria may also play a significant role in fatal heart attacks.
The Finnish and British researchers’ study, which was published on August 6, 2025 in the Journal of the American Heart Association, identified mouth bacteria, particularly viridans streptococci, as one of the causes.
Heart arteries from 96 vascular surgery patients and coronary plaques from 121 people who died suddenly outside of hospitals were analyzed by the researchers. They detected bacterial DNA in nearly half the cases, with viridans streptococci being the most common bacteria found, appearing in 42% of coronary plaques and 43% of surgical samples.
These simple bacteria settle in atherosclerotic plaques and form biofilms—sticky bacterial communities with protective shields that are embedded deep within arterial plaques. Hidden biofilms go undetected by the body’s immune system.
When plaques rupture, bacterial particles are released, triggering a significant immune response. Consequently, this inflammation has the potential to destabilize the arterial walls and result in sudden rupture, which can cause heart attacks. According to Laboratory tests, viridans streptococci activate toll-like receptor 2 (TLR2), a bacterial signalling pathway that contributes to arterial inflammation.
This breakthrough highlights the importance of oral hygiene in preventing cardiovascular disease. Maintaining good oral health may help reduce the risk of heart attacks by preventing the formation of bacterial biofilms in arteries.
How to protect oral health?
Brush your teeth twice a day for two minutes, cleaning your tongue and the spaces between your teeth with floss or water flossers to maintain good oral health. Eat well, limit sugary foods, and change your toothbrush every three to four months. Visit a dentist annually for checkups, as they may recommend more frequent visits depending on your situation. If you have oral health issues, don’t smoke and call your dentist right away.
