Last updated on October 30, 2019
The Gut Bacteria/Heart Disease Connection
Having unhealthy gut bacteria puts you at a higher risk for atherosclerosis—or hardening of the arteries—than smoking, cholesterol levels, obesity, or diabetes. Atherosclerosis is the leading cause of heart disease.
That’s because the root cause of heart disease is inflammation. In fact, most modern health disorders are rooted in inflammation, including arthritis, diabetes, obesity, dementia, depression, and inflammatory bowel disease. Cardiovascular disease is no exception.
So where does the gut bacteria/heart connection come in? Researchers have discovered that an unhealthy microbiome—the term given to our inner garden of gut microbes—is pro-inflammatory while a healthy gut microbiome is anti-inflammatory. Unfortunately, in the United States, we have the unhealthiest gut microbiomes studied thus far.
Having a weakened gut lining or leaky gut can lead to cardiovascular disease. A leaky gut allows bacteria and food particles into the bloodstream which can cause inflammation. This inflammation can become especially severe if lipopolysaccharides (LPS) get into the bloodstream. Higher levels of LPS can lead to metabolic problems and increase the likelihood of heart disease.
A recent study found that women experiencing hardening of the arteries also showed less gut microbiota diversity while women with healthy arteries showed healthier gut bacteria. (1) A diverse array of bacteria is linked to better cardiovascular health.
The new research also found that in healthy subjects, diverse and healthy gut bacteria produced more indole propionic acid (IPA), a neuroprotective antioxidant that also has been shown to lower risk factors of diabetes. (1) (2)
The Gut Microbiome and High Blood Pressure
It turns out there is more to high blood pressure than reducing your salt intake. Researchers have found high blood pressure, which increases your risk of heart attack and stroke, can also be linked to the gut microbiome. (3)
The key is in a compound called propionate, one of several short-chain fatty acids (SCFAs) produced by healthy gut bacteria. Scientists are learning that SCFAs such as propionate and butyrate are instrumental to the health of the brain and body in many ways, with propionate being specific to the cardiovascular system.
How to Foster a Heart-Healthy Gut Microbiome
Although taking propionate may help, it won’t do much good if it’s battling a minefield of infectious and inflammatory gut bacteria. Just as healthy gut bacteria produce SCFAs that are good for us, bad bacteria produce the highly inflammatory compound lipopolysaccharide (LPS).
Eat fiber and prebiotic foods.
The key to a heart-healthy gut microbiome is to eat about 25–30 grams of fiber a day via a very diverse array of vegetables and modest amounts of fruit (fruits are high in sugar and too much sugar is inflammatory).
Fiber is full of short-chain fatty acids that are not only vital for colon health but also reduce the risk of heart disease by protecting the heart. The main short-chain fatty acids are acetate, propionate, and butyrate. They help the heart by regulating blood pressure and cholesterol. Good sources of these fatty acids include artichokes, grains (especially cereal like Raisin Bran), and carrots.
You can also get a good dose of prebiotics from fiber. Prebiotics contain the precursors needed for bacteria to make special chemicals that our bodies absorb to lower blood pressure. Good sources of prebiotic-heavy fiber include garlic, onions, asparagus, sweet potatoes, and whole wheat.
Diversify your vegetables.
It’s the diversity of vegetables that matters most, with research increasingly confirming that a diverse gut microbiome is what lies behind good health and a lower risk of disease.
Switch up the vegetables you eat regularly and shop at world markets unfamiliar to you to try new types of produce. Even a teaspoon of different, new veggies each day is enough to help colonize the friendly bacteria that will work to keep your heart healthy.
In this fiber-rich environment, supplementing with SCFAs such as butyrate and propionate can help boost your gut bacteria to produce even more of their own SCFAs. (4)
Consume probiotics daily.
Like the prebiotics mentioned above, it’s also important to have a daily source of probiotics. Probiotics are good bacteria that exist in the digestive tract and promote gut health. They help with digestion and reduce inflammation. Probiotics are also edible, live bacteria found in yogurt, kombucha, fresh dill pickles, sauerkraut, miso, and certain aged cheeses (cheddar, gouda, and mozzarella).
You can also take probiotic supplements for an extra boost of friendly bacteria, but a healthy, probiotic-rich diet should ideally be your primary source.
Keep in mind probiotics may affect patients differently based on their current state of health. Your best bet is to contact a Functional Medicine practitioner to find the probiotic strain most suitable for you.
Additional Gut Health/Heart Health Tips
Additional ways to keep your gut and your heart healthy are to:
- Make sure to keep your blood sugar stable by eliminating sugars, sweeteners, and processed carbohydrates.
- Avoid foods that cause your immune system to react negatively (e.g. gluten and dairy).
- Avoid toxin chemicals in your foods and body products that can kill good bacteria. This includes reducing the use of NSAIDS like Advil or aspirin which can eat away at your stomach lining and cause leaky gut.
- Only use antibiotics when strictly necessary. They can alter the gut microbiome because they don’t differentiate between good and bad bacteria.
- Exercise daily. Exercise has been shown to positively influence your gut microbiome.
- Menni, Cristina, Chihung Lin, Marina Cecelja, Massimo Mangino, Maria Luisa Matey-Hernandez, Louise Keehn, Robert P Mohney, et al. “Gut microbial diversity is associated with lower arterial stiffness in women.” European Heart Journal 39, no. 25 (2018): 2390–2397. doi: 10.1093/eurheartj/ehy226.
- Tuomainen, Marjo, Jaana Lindström, Marko Lehtonen, Seppo Auriola, Jussi Pihlajamäki, Markku Peltonen, Jaakko Tuomilehto, et al. “Associations of serum indolepropionic acid, a gut microbiota metabolite, with type 2 diabetes and low-grade inflammation in high-risk individuals.” Nutr Diabetes 8, no. 35 (2018). doi: 10.1038/s41387-018-0046-9.
- Delbrück, Max. “How dietary fiber and gut bacteria protect the cardiovascular system.” Medical Xpress. Last modified December 2018. https://medicalxpress.com/news/2018-12-dietary-fiber-gut-bacteria-cardiovascular.html.
- Kharrazian, Datis. “Oral Tolerance Part II: The overlooked power of short-chain fatty acids (SCFAs) for immune health, brain health, and food sensitivities.” Dr. K. News. Last modified September 2018. https://drknews.com/short-chain-fatty-acids-scfas-for-immune-health-brain-health-and-food-sensitivities/.