Two recent studies published in Nature Medicine have shown that the gut microbiomes of those with heart disease are unique from the gut microbiomes of healthy individuals.
The studies included 372 participants with ischemic heart disease and two groups of matched controls: one group of healthy individuals and one group that matched the heart disease patients in terms of obesity and diabetes status but who had no heart disease diagnoses. In total, over 1,200 people were included in the studies.
The researchers quantified the bacterial species in the guts of the participants and also measured over 1,000 compounds circulating in their bloodstreams. They found that some disturbances in the gut microbiome occurred in the early stages of pre-obesity and type 2 diabetes, usually years before the patients experienced any symptoms of heart disease. Those changes persisted in patients who developed heart disease, but the development of heart disease was also associated with specific additional alterations to gut microbiome composition. In particular, the microbiomes of heart disease patients showed a decreased diversity of bacteria known to produce healthful compounds such as short chain fatty acids and increased numbers of bacteria associated with negative health outcomes. These findings suggest that gut microbiome alterations start years before patients develop heart disease and continue to worsen as the disease develops.
While these studies show associations and not causal links, one author noted that past studies have suggested that gut microbiome disturbances may play a role in the development of heart disease. The gut microbiome is linked to many health outcomes, including impacts on the brain, immune system, body weight, and more. Like many other health issues, the gut microbiome can be improved by eating a whole-food, plant-based diet and limiting processed foods. Fermented foods, probiotics, and dietary diversity in particular seem to improve gut microbiome health.