If you’re concerned about heart disease, current research is showing another compelling reason to adopt a plant-based lifestyle. The research focuses on a compound called “TMAO,” or “trimethylamine N-oxide,” which is produced by the interaction between certain food and microbes in your gut. The higher your TMAO level, the more susceptible you are to atherosclerosis, which is plaque development in the arteries of your heart and brain wall. This plaque build-up increases your risk of heart attack and stroke.
A clue to future disease
A January 2017 study published in European Heart Journal found that high levels of TMAO in the blood are a key danger sign among people who go to an emergency room with chest pain. High TMAO shows that you may be six times more likely to suffer a heart attack or stroke, or need surgery to repair an artery.
High cholesterol has historically been the classic biomarker for heart disease. But doctors are starting to recognize TMAO levels as an important biomarker to screen patients for heart disease. Even if you have relatively low cholesterol or low blood pressure, high TMAO blood levels point to an increased risk.
Stanley Hazen, the head of Preventive Cardiology, and a team at The Cleveland Clinic first identified TMAO as a cardiac biomarker. The researchers found that participants with the highest levels of TMAO had a 2.5 time higher risk for a major cardiovascular event (heart attack, stroke or death) than those with the lowest levels during three years of follow-up. TMAO still predicted risk even after adjustments were made for risk factors such as diabetes, high blood pressure and diabetes. The research was published in New England Journal of Medicine in 2013 and Nature Medicine in 2013.
Sources of TMAO
Your digestive tract is packed with trillions of bacteria, and the balance within this complex ecosystem is essential to your health. Some of the bacteria feed on carnitine and choline– nutrients plentiful in meat, egg yolks and high-fat dairy products. Carnitine is also found in smaller amounts in poultry and fish; in fact, all animal foods contain some carnitine. Beef and lamb are the most dangerous—they contain about 50 to 160 mg of carnitine per serving, compared to between 3 and 7 or 8 mg in pork, seafood, chicken and high-fat dairy products. Egg yolks also contain high amounts of choline.
Beware of energy drinks
Energy drinks such as Monster and Rock Star, and supplements promoted for weight loss, gaining muscle and athletic performance, are also sources of carnitine.
How TMAO affects you
When you eat foods that contain carnitine and choline, they are digested by your gut bacteria, which produces a compound called TMA. TMA turns into TMAO in your liver. TMAO alters cholesterol metabolism and leads to the progression of plaque development in the arteries. The research from Cleveland Clinic shows that within a couple of hours after meat-eaters ate a steak, TMAO levels soared.
The study showed that when vegans consumed a steak, however, they produced virtually no TMAO. The researchers hypothesized that the gut flora of vegans may impact the metabolism of carnitine in a way that does not lead to the production of TMAO. The study concluded that intestinal microbiota play a large role in the link between high levels of red meat consumption and the risk of CVD.
TMAO and your kidneys
Blood vessels in your kidneys are vulnerable to TMAO as well. In a January, 2015 study of TMAO and kidney disease published in Circulation Research, researchers at the Cleveland Clinic followed more than 3,500 subjects, most with normal kidneys when the study began. High TMAO levels at baseline were associated with chronic kidney disease and higher mortality five years later.
Diet makes the difference
As you would expect, if you eat a diet high in carnitine and choline, you encourage the growth of the bacteria that feast on them, which leads to more TMAO and more damage.
A plant-based approach such as Ornish Lifestyle Medicine, which does not include animal foods that contain carnitine and choline, and is rich in nutrients that promote healthy gut bacteria, continues to be the most effective way to prevent heart disease, stroke and the progression of kidney disease. “We were able to show that drugging the microbiome is an effective way to block diet-induced heart disease,” Dr. Hazen of the Cleveland Clinic said about the study. “It’s much like how we use statins to stop cholesterol from forming in a body’s cells.”
Just how bad for your heart health is high fat food? Read How Your Body Responds to Just One High-Fat Meal.
This article originally appeared on Ornish Living.
