Healthy Gut = Healthy Heart
Written by Dr. Suzanne Tang
March 21, 2023
It is common knowledge that a healthy diet and regular exercise can help reduce the risk of cardiovascular disease but is there more to this story? There is mounting evidence that the bacteria in our gut affects multiple markers of heart health, such as blood sugar, insulin levels, blood pressure, inflammation, plaque and clotting formation, endothelial health and weight, thereby significantly influencing the risk of atherosclerosis or hardened arteries, type 2 diabetes, hypertension, heart attacks, strokes and obesity.
It turns out that the old adage “You Are What You Eat” is partially true. Rather “You Are What Your Microbes Make From What You Eat” gives us more of a complete picture.
A large study of 1,500 people found that the gut microbiome played an important role in promoting “good” or protective HDL cholesterol. Certain unhealthy species in the gut microbiome may also contribute to heart disease by producing trimethylamine N-oxide (TMAO). Bacteria within the microbiome convert choline and L-carnitine, both of which are nutrients found in red meat, eggs, shellfish, salt water fish, pork, lamb and high fat dairy to TMAO.
TMAO is a chemical that contributes to blocked arteries, which may lead to heart attacks or stroke. People with the highest blood TMAO levels are 62% more likely to have heart problems compared to those with the lowest levels, according to a study in the Journal of the American Heart Association. In a 10 year study published in the Journal of the American College of Cardiology, women with the greatest TMAO increases in their blood had a 67% higher chance for developing heart disease compared to women whose TMAO levels rose the least. The group with high TMAO levels was also more likely to eat a diet rich in animal products and low in vegetables.
Elevated TMAO is linked to:
Heart attacks
Strokes
Hypertension
Non-alcoholic fatty liver
Chronic kidney disease
Type 2 diabetes and metabolic syndrome
Colon and prostate cancer
Curious about your TMAO levels? I am too. Ask your doctor to order TMAO markers with your next routine blood draw.
Other beneficial bacteria within the gut microbiome, particularly Lactobacilli, may help reduce cholesterol when taken as a probiotic. Lactobacillus rhamnosus has been found to effectiv ely reduce plasma TMAO levels in human and animal studies. Other studies demonstrated that either reduced salt or increasing Lactobacillus spp with probiotic treatment improved blood pressure regulation, arterial compliance, vascular function, and insulin sensitivity.
As discussed in my previous article, “The Gut-Brain Axis: Connection Between Mood and Gut Bugs,” beneficial bacteria digest fiber producing short-chain fatty acids or SCFA. SCFA, such as butyrate are not just healthy for the brain and the gut, but also for the heart. SCFA has been shown to regulate blood pressure and reduce inflammation, potentially decreasing the risk for hypertension and heart disease. In addition, certain microbes are associated with type 2 diabetes and obesity, conditions that increase the risk for strokes, heart attacks and hypertension. Higher microbial diversity along with more butyrate producing bacteria were associated with individuals with less risk of type 2 diabetes and lower insulin resistance.
If you have been reading my gut microbiome newsletter series and additional research on gut health, you are practically an expert on dietary factors to improve microbiome diversity. If you are wondering if I’ll be writing about other topics besides the gut, you are in luck! This is the final gut health newsletter for a while :) A plant-based, high fiber, Mediterranean based diet low in red meat, dairy, sugar and salt is most beneficial for improving microbial diversity, reducing TMAO and inflammation and improving SCFA to prevent and address heart disease.
Yours in Wellness,
Dr. Suzanne Tang, ND, LAc
