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A new study shows an association between gut bacteria and plaques related to heart disease. Su Arslanoglu/Getty Images
  • New research found a link between gut bacteria and plaque buildup in heart arteries.
  • After examining heart imaging and gut bacteria, researchers found a strong association between two types of bacteria.
  • The study shows the gut bacteria associated with the buildup of fatty deposits in heart arteries were similar to the bacteria in the mouth.

A new study finds that what is going on in your gut can significantly impact your overall heart health.

A new study, published July 12 in the journal Circulation, showed an association between gut bacteria and a type of fatty buildup or plaques associated with an increased risk of cardiac events.

This type of plaque called coronary atherosclerotic plaques is caused by excess fatty and cholesterol deposits.

Researchers examined the gut bacteria and cardiac imaging of 8,973 participants who didn’t have heart disease and were between the ages of 50 to 65.

Researchers are now planning follow-up studies on the connection of the oral and gut microbiome with atherosclerosis, and are also planning to search for factors affecting the levels of gut streptococci, Fall added.

“This is the first study in participants without any prior cardiovascular disease, which means that the results are not affected by medications or lifestyle changes due to disease,” Tove Fall, senior study author and professor in Molecular Epidemiology, Department of Medical Sciences, Molecular Epidemiology, and the SciLifeLab, Uppsala University, told Healthline. “It is also very large and applies state-of-the-art techniques to capture the microbiome and atherosclerosis.”

There is a strong correlation between gut health and cardiovascular health.

“An unhealthy gut is considered a risk factor for developing a spectrum of cardiovascular diseases including heart failure, and the appearance of plaques in blood vessels (atherosclerosis), which may lead to events such as heart attack and stroke,” said Dr. Sara Mesilhy, Gastroenterologist, Royal College of Physicians UK.

The exact mechanism of the gut-heart link is under evaluation but generally, it’s related to chemicals or processes associated with gut bacteria. These bacteria can invade the gut barrier and enter the circulation, causing infection of plaques or infection at other sites.

This can lead to activation of the inflammatory process in our body, causing systemic inflammation, Mesilhy explained. This can affect our immune cells in a negative way.

Inflammatory factors can act on the blood vessels, affecting their basic functions or causing them to lose their elasticity. This is the first step in the process of plaque formation and atherosclerosis of major blood vessels, Mesilhy explained.

After analyzing cardiac imaging and gut flora, one of the most significant associations researchers found was with two specific bacteria.

Streptococcus species were closely linked with biomarkers of systemic inflammation in circulation. These were the same species found located in the mouth leading researchers to link the bacteria with disease of the oral cavity.

Streptococcus anginosus and Streptococcus oralis subsp. oralis were the most abundant in people with coronary atherosclerosis in [this study group],” said Mesilhy.

Previous experimental studies in mice suggest exposing the animals to Streptococcus species orally provokes the growth of plaque, Mesilhy added.

Research on the gut microbiome has leading to many discoveries connecting specific bacteria to certain states of health.

“It is speculated that certain bacteria may release specific factors that benefit heart health, or these bacteria species may help suppress inflammation, or possibly the growth of other bacteria that release substances that are harmful to the heart,” said Dr. William Li, medical doctor and New York Times bestselling author of “Eat to Beat Your Diet: Burn Fat, Heal Your Metabolism, and Live Longer.”

“The reason behind these associations is being researched.”

Researchers have discovered that some of the species associated with the buildup of fatty deposits in heart arteries were tied to the levels of the same species in the mouth. This suggests that bacteria has a far-reaching impact on numerous bodily functions.

“Bacteria found inside the tube of the gut can be beneficial or harmful,” said Li.

“Beneficial bacteria can communicate with other organs by releasing [short-chain fatty acids] and other factors that are still being discovered. These substances are released into the bloodstream where they can [reach] organs that are far removed from the gut, such as the heart or the brain.”

On the other hand, in certain conditions such as heart failure, bacteria seep from inside the gut to outside through weakened parts of the intestinal lining. This is called bacterial translocation, Li noted.

Once the bacteria get into the bloodstream, they can reach other organs, including the heart, where they can cause infection or inflammatory damage.

When this damage occurs on the lining of blood vessels (called the endothelium) feeding the heart, fatty deposits called atherosclerotic plaques form on those damaged portions, Li explained.

The growing plaque causes more inflammation, which causes more endothelial damage, and eventually, this can cause the plaque to block blood flow.

A new study shows an association between gut bacteria health and coronary atherosclerotic plaques.

Researchers looked at cardiac imaging and gut flora, which revealed a significant link between two types of bacteria.

The study also showed that some of the species associated with the buildup of fatty deposits in heart arteries were tied to the levels of the same species in the mouth.

These results suggest that bacteria impacts numerous bodily systems.