The bacteria that live in our gut and play critical roles in our health change according to the foods we eat. Trillions of microbes live in your intestinal tract, and this collection of microbes is called the gut microbiota. It contains 100-times more genes than the rest of your body, and they have a striking impact on your cardiovascular health. This connection is a key example of the brain-gut relationship.
Researchers are discovering an increasing amount of evidence that the gut microbiome has a role in a person’s overall health and chances of developing any disease. So far, Type 2 diabetes, obesity, and metabolic syndrome are a few of the conditions that epitomize the impact of gut microbiome interactions. All three have a crucial role in cardiovascular health.
Trimethylamine-N-oxide
Some of the most credible evidence that demonstrates a link between the microbiome and cardiovascular health involves a substance called trimethylamine-N-oxide (TMAO). Trimethylamine-N-oxide is the compound made by the liver after bacteria in the intestinal tract digest certain nutrients such as L-carnitine, lecithin, and choline. These nutrients are found in foods like fish, eggs, meat, and dairy.
When you eat more of these foods, your body produces more TMAO. Higher levels of TMAO are linked with hardening of the arteries, diabetes, chronic kidney disease, colon cancer, and an increased risk of cardiovascular events. In addition, there are links between the composition of the microbiome and various risk factors for cardiovascular disease, such as impaired metabolism, inflammation, and high blood pressure.
The relationship between TMAO and cardiovascular risk caught the attention of more scientists, and now experts are exploring new ways to test for this substance in the blood to help predict future risk of stroke, heart attack, and death among people who otherwise appear to be healthy.
Researchers at the Cleveland Clinic developed a test that measures blood levels of TMAO. They found that the study subjects with higher levels of TMAO had a higher likelihood to accumulate cholesterol in their arteries. This increased their risk of having a stroke or heart attack.
More specifically, researchers evaluated the strength of the TMAO test and found that individuals who had the highest levels of TMAO had a 2.5 times increased risk for experiencing a major cardiovascular event than those who had the lowest levels during three years of follow-up.
How to lower TMAO levels
You can follow a variety of steps to lower TMAO levels, create a healthier microbiome, and lower your risk of cardiovascular events.
- Eat a Mediterranean, vegetarian, and/or vegan diet: Research has shown that vegans and vegetarians have microbiome bacteria that produce less TMAO than do meat-eaters. The same is true for those who follow a Mediterranean diet, which includes eating more vegetables, fruits, whole grains, and healthy fats, smaller portions of red meat and dairy. It includes moderate consumption of fish, beans, poultry, and eggs.
- Take prebiotics and probiotics: Prebiotics are plant fibers in fruits and vegetables that nourish probiotics, the beneficial bacteria in the gut. Research shows that prebiotics and probiotics can reduce TMAO levels in animal studies. Some food sources of prebiotics include jicama, asparagus, chicory root, dandelion greens, onions, leeks, and garlic. Probiotics are found in yogurt, kefir, tempeh, and fermented vegetables like kimchi and sauerkraut.
- Take vitamins B and D: At least one study in adults has shown that supplementation with B vitamins (i.e., folic acid and vitamins B6 and B12) along with vitamin D3 (1,200 IU) reduces levels of TMAO.
- Take resveratrol supplements: This polyphenol, found in the skins of red grapes, berries, peanuts, and red wine has been shown to reduce blood levels of TMAO in mice prone to atherosclerosis.