Gut-Heart Connection: Is the Microbiome The Missing Piece to Cardiovascular Health?
Heart health is usually associated with diet and exercise, but groundbreaking research reveals the gut microbiome has a powerful impact. A fascinating relationship between gut health and heart health exists, called the gut-heart connection. It’s incredible how tiny microbes can alter complex processes involved in cardiovascular function. Let’s discover how the gut microbiome affects cardiovascular health, and uncover what you can do to optimize this in your life.
What is the Gut Microbiome?
Your gut microbiome is a complex ecosystem of trillions of bacteria, fungi, and other microbes. It has incredible impact on your health. The gut microbiome has many functions:
- Breaking down food
- Creating byproducts
- Short-chain fatty acids (SCFAs)
- TMAO (trimethylamine N-oxide)
- Vitamins and minerals
- Bacteriocins (antimicrobial properties)
- Influences the thickness of the mucosal gut lining
- Interacts with receptors in the gut lining (hormone, immune)
Does Gut Health Impact Cardiovascular Health?
When the gut microbiome is unbalanced, it is a condition called dysbiosis. Dysbiosis alters the diversity of the gut microbiota, and thus its far-reaching impacts on the human body, and heart health. Research has associated dysbiosis with cardiovascular disease.
The functions of the gut microbiome, and the byproducts it produces can either beneficially or negatively influence cardiovascular health. Microbes in the gut are uniquely positioned to influence receptors along the gut lining which guide inflammation and hormone production. Microbes in the gut also create byproducts. Since the job of the gut is to absorb nutrients, inflammatory triggers, hormones and microbial byproducts can easily access the systemic circulatory system. This is how two systems in the body, which seem physically separate, can impact each other. Let’s explore what researchers know about the ways gut health impacts cardiovascular health.
4 Ways Gut Microbes Impact Heart Health
Research studies suggest the gut microbiome has the potential to impact major factors in cardiovascular risk, including:
- Blood Pressure: The SCFA, butyrate, has been linked in studies to lower blood pressure, potentially by reducing inflammation. Higher TMAO levels, a metabolite of gut microbes, are associated with hypertension.
- Inflammation: SCFAs modify the release of cytokines that trigger inflammation, such as IL-18. Studies show SCFAs have anti-inflammatory effects by reducing pro-inflammatory cytokines, such as TNF-alpha.
- Cholesterol: SCFAs play vital roles in modulating cholesterol metabolism. Their presence triggers the expression of proteins involved in lipid metabolism. Some probiotics have high bile salt hydrolase activity, which breaks down bile salts needed for cholesterol absorption in the intestines. A 4-week study involving a group of healthy overweight individuals given probiotics (two Lactiplantibacillus plantarum strains) found lower apolipoprotein (ApoB) and LDL levels, as well as higher HDL antioxidant capacity. These metabolic profile shifts suggest the probiotics increased protection against atherosclerotic disease.
- Glucose Metabolism: The SCFA, propionate supports B-cells in the pancreas, supporting glucose intake by cells. SCFAs also stimulate the secretion of gut hormones which are important in glucose metabolism (such as PYY, a satiety hormone, and GLP-1 which is involved in glucose-dependent insulin secretion).
Can a Gut-Healthy Diet Lower Cardiovascular Risk?
Advances in clinical research have uncovered fascinating details about the impact of certain dietary choices on the makeup of the gut microbiota and its influence on cardiovascular wellness. In particular, plant fibre and protein-source appear to play a role in gut health, and thus the potential to impact cardiovascular wellness.
Fiber and Heart Health
Eating more fibre does more for heart health than trap cholesterol to reduce its reabsorption in the gut. Some plant fibres act as prebiotics enhancing the ability of probiotics to thrive in the gut. Plus, these otherwise indigestible plant fibres can be fermented by probiotics to create SCFAs. Research has discovered SCFAs, such as butyrate, propionate, and acetate, have numerous heart-protective effects:
- Reduce inflammation
- Lower blood pressure
- Regulating blood pressure and improving arterial function
- Lowering cholesterol levels by promoting its excretion from the body
Eating plant fibres is a well-known way to support gut health. Mounting evidence suggests eating more plant fibre may offer a natural strategy to increase SCFA production, which could support cardiovascular health.
Animal Protein and CVD
Eating animal proteins offers certain microbes in the gut the substrates (choline, betaine, L-carnitine) to create TMA, which the liver converts into trimethylamine-N-oxide (TMAO). This occurs at higher rates when the gut microbiome is disrupted. Researchers are concerned dysbiosis poses a problem in people at risk of cardiovascular disease – studies show higher TMAO levels are linked with hypertension and the development of cardiovascular disease. Even in healthy, middle-aged participants, higher TMAO levels have been linked with greater cardiovascular risk in large population studies.
In recent years, researchers have uncovered a concerning association between higher TMAO levels and alterations in the cardiovascular system known to increase disease risk:
- Changes in cholesterol metabolism
- Foam cell formation (atherosclerosis)
- Platelet hyperactivity (thrombosis)
Can Eating Plant-Protein Improve Cardiovascular Risk?
Yes, it may. According to 17 clinical studies, investigating the impact of plant- versus animal-derived protein and the incidence of cardiovascular disease. Cardiovascular risk increases with heightened TMAO levels which is higher among those who eat more animal-derived protein.
A Healthy Gut Diet for Heart Health
A diet rich in plant-based fibres supports the gut microbiome. In the presence of prebiotic plant fibres, the gut microbiome is better equipped to create more SCFAs, fewer TMAOs, and balance bile acids. This in turn can support gut integrity, reduce inflammation and may lower cardiovascular risk.
Here are some excellent fibre sources to include in your diet, but remember that everyone’s dietary needs are unique – choose items that are best suited for you:
- Leafy greens (kale, spinach, Swiss chard)
- Legumes (chickpeas, lentils, black beans)
- Whole grains (quinoa, oats, brown rice)
- Fruits (apples, berries, bananas)
- Nuts and seeds (flaxseeds, chia seeds, almonds)
Heart-Healthy Dinner Ideas
In the CSNN Holistic Kitchen discover delicious ideas for gut-healthy, heart-healthy meals, such as:
- Sheet Pan Tofu and Veggies
- Eggplant Lentil Salad
- Baked Tofu Skewers
- Rainbow Bowl
The Gut-Heart Connection
The connection between the gut microbiome and heart health is being uncovered by science more and more, every day. Put a focus on gut health – it may be a potential strategy for lowering cardiovascular risk.
How to Learn More
The Canadian School of Natural Nutrition (CSNN) offers a variety of programs designed to help you understand the connections between nutrition, lifestyle, and health, as well as how to use motivational interviewing to help others achieve wellness. Whether you’re interested in deepening your knowledge, learning how to cook healthier meals, or ready to pursue a career in holistic nutrition, CSNN has options for you.
Ready to learn more? Join CSNN today.
Scientific References:
The human-microbiome superorganism and its modulation to restore health. Int J Food Sci Nutr. 2019 Nov;70(7):781-795.
Gut microbiome-mediated mechanisms for reducing cholesterol levels: implications for ameliorating cardiovascular disease. Trends Microbiol. 2023 Jan;31(1):76-91.
Intestinal barrier dysfunction as a therapeutic target for cardiovascular disease. Am J Physiol Heart Circ Physiol. 2020 Dec 1;319(6):H1227-H1233.
Probiotics: A Potential Strategy for Preventing and Managing Cardiovascular Disease. Nutrients. 2024 Dec 27;17(1):52.
Lactiplantibacillus plantarum strains KABP011, KABP012, and KABP013 modulate bile acids and cholesterol metabolism in humans. Cardiovasc Res. 2024 May 29;120(7):708-722.
The Role of Short Chain Fatty Acids in Inflammation and Body Health. Int J Mol Sci 2024 Jul 5;25(13):7379.
Role of Gut Microbiota-Generated Short-Chain Fatty Acids in Metabolic and Cardiovascular Health. Curr Nutr Rep. 2018 Dec;7(4):198-206.
Plasma trimethylamine N-oxide (TMAO) levels predict future risk of coronary artery disease in apparently healthy individuals in the EPIC-Norfolk Prospective Population Study. Am Heart J 2021 Feb 21;236:80-86.
Dietary intake of plant- and animal-derived protein and incident cardiovascular diseases: the pan-European EPIC-CVD case-cohort study. Am J Clin Nutr. 2024 May;119(5):1164-1174.
Short-Chain Fatty Acids and Their Association with Signalling Pathways in Inflammation, Glucose and Lipid Metabolism. Int J Mol Sci 2020 Sep 2;21(17):6356.