Diets high in animal-based foods are a source of trimethylamine, or TMA, which is converted by the liver into trimethylamine-N-oxide, TMAO, which promotes the buildup of fatty plaque in arteries.
"The connection between TMAO and cardiovascular disease has tended to focus the conversation on how animal-based diets cause negative health consequences," said Veronika Kivenson, the study's lead author and a postdoctoral fellow in the OSU College of Science, in the press release. "But in analyzing data from foundational gut microbiome studies, we uncovered evidence that one type of bacteria associated with meat consumption can take the TMA, as well as precursors to TMA, and metabolize them without producing any TMAO. That means those bacteria are in effect severing a key link in the cardiovascular disease chain."
Related: #NaturallyInformed: Health Benefits for the Host Kerry Acquires Bio-K Plus Inflammatory Foods Associated with CVD RiskThe bacteria are of the Bilophila genus. Kivenson says in the press release that research shows animal-based diets cause a rapid increase in Bilophila in the gut. The bacterium was only identified 31 years ago, and since then has been classified as a pathobiont—an organism that normally has a symbiotic relationship with its host, but can become disease-causing under certain circumstances.
"The data we reviewed show significantly more Bilophila in the microbiomes of healthy people compared to those with cardiovascular disease, and that Bilophila numbers go up in response to a diet based on meat compared to a plant-based diet," Kivenson said in the release. "Our findings suggest Bilophila's role in the microbiome and human health might depend on the specific context and that their potential as a probiotic that mitigates animal products' role in heart disease should be studied further."
"The organisms in your stomach have been shown to affect the development of myriad disease states," said co-author Steve Giovannoni, distinguished professor of microbiology at OSU. "But the mechanisms—what is actually happening behind the connections among diet, health and microbiota—have generally been hard to pin down. More research into Bilophila cell biology and ecology is needed, but our study presents a clearly defined mechanism with potential for a big impact on human health."