According to a report on Endocrine Web, research from the Cleveland Clinic shows that a compound called trimethylamine N‑oxide (TMAO) has been linked to higher risk for atherosclerosis, heart attacks, heart failure, kidney failure and strokes.
Apparently, “TMAO threatens heart and brain health by encouraging the deposit of more cholesterol in artery walls. It also interferes with the process that whisks LDL cholesterol out of the body for elimination in the stool.” In further studies, researchers found a “clear link between higher TMAO levels and elevated three-year risk of heart attack, stroke and death.”
The concept that gut flora contribute to atherosclerosis, heart failure and chronic kidney disease opens up exciting new nutritional and interventional prospects.
From the research conducted to date, it is known that certain gut bacteria, also known as the microbiome, can convert two specific nutrients, choline and l‑carnitine, into trimethylamine (TMA), which then makes it’s way to the liver where an enzyme converts TMA to TMAO. From there TMAO ends up in the bloodstream, affecting the heart, brain and other organs. Choline and l‑carnitine are found in red meat, egg yolks, high-fat dairy products and some other foods.
However, researchers agree that people should not immediately assume that you should not eat red meat, eggs, or some of the other foods just mentioned, as it is not yet clear exactly what increases TMAO. “It is possible that other dietary sources may also increase TMAO including processed foods and carbohydrates,” Mente says on the Endocrine Web report.
At this stage there is an association between choline and l‑carnitine, however, this does not mean these food sources are the causation of higher rates of heart attack and so forth. In fact, the consumption of eggs has been shown to be healthy and even beneficial for cardiovascular health in some studies. Therefore, before any specific dietary exclusions can be recommended, more research is needed into various other dietary sources that could increase TMAO.
The important thing to keep in mind is that studies are in fact linking the importance of gut bacteria to heart failure, kidney disease, brain health and various other aspects of health. And, they also know that dietary interventions can modify the gut bacteria, too.
Stanley Hazen, Chair of Cellular and Molecular Medicine and Section Head of Preventive Cardiology and Rehabilitation at the Cleveland Clinic supports this view, saying that, “the concept that gut flora contribute not only to atherosclerosis but also to heart failure and chronic kidney disease, opens up exciting new nutritional and interventional prospects.”
Altering TMAO production is a case in point. In December 2015, the Cleveland Clinic reported they’d found a non-toxic chemical compound called DMB that could reduce TMAO.
According to the Endocrine Web report:
“DMB kept TMAO levels in the blood lower and also led to a shrinking of artery plaque and lower levels of TMA-producing gut bacteria.”
Interestingly, extra virgin olive oil and red wine also contain the chemical compound DMB with one study showing, Hazen noted, “a Mediterranean diet was associated with lower TMAO levels.”
According to a study in Infectious Diseases and Translational Medicine, in mice, the DMB compound was shown to slow down the microbes production of TMA, even when mice were fed a Western diet with high amounts of choline.
At this stage the only evidence available is in mouse models, but such research does provide researchers with insight into how dietary interventions such as the Mediterranean diet, a diet that has been shown to reduce cardiovascular risk factors, may alter gut microbes and provide beneficial treatment for cardiovascular and brain health. It is suggested that the alteration of gut microbes is perhaps one of the mechanisms by which the Mediterranean diet exerts its many beneficial health effects.
When it comes to understanding the human gut bacteria, researchers such as Hazen and others agree that there is still much left to be explored and answered.
Given that extra virgin olive oil contains the DMB compound, it is likely that many of its other phenols, polyphenols and antioxidants could also exert positive benefits on gut bacteria, which we’ll likely see more research about in the future.