The gut and the heart may seem like two separate systems, but emerging research reveals a strong connection between gut health and cardiovascular wellness. The gut microbiome—the vast ecosystem of bacteria, viruses, and fungi in the digestive tract—plays a crucial role in regulating inflammation, cholesterol metabolism, and even blood pressure. Functional medicine takes a root-cause approach to heart disease prevention by addressing gut health as a foundational component of cardiovascular wellness.
This blog post explores the gut-heart axis, the role of the microbiome in cardiovascular health, and practical strategies for optimizing gut health to support a strong and healthy heart.
The Gut-Heart Axis: How the Microbiome Influences Cardiovascular Health
The gut-heart axis refers to the biochemical and metabolic interactions between the gut microbiota and the cardiovascular system. Research has shown that an imbalanced gut microbiome (dysbiosis) contributes to systemic inflammation, atherosclerosis, hypertension, and metabolic disorders that increase the risk of heart disease (Tang et al., 2022).

Here are some key ways the gut impacts heart health:
1. Inflammation and Atherosclerosis
Chronic inflammation is a major driver of cardiovascular disease. An unhealthy gut microbiome can promote inflammation by producing harmful metabolites, such as lipopolysaccharides (LPS), which trigger immune system activation and contribute to plaque buildup in arteries (Vujkovic-Cvijin et al., 2022).
2. Trimethylamine-N-Oxide (TMAO) and Heart Disease
Certain gut bacteria convert dietary choline and L-carnitine (found in red meat and eggs) into trimethylamine (TMA), which is then processed by the liver into trimethylamine-N-oxide (TMAO). High TMAO levels are associated with increased arterial plaque formation, inflammation, and a higher risk of stroke and heart attack (Koeth et al., 2020).
3. Cholesterol Metabolism
The gut microbiome plays a role in regulating cholesterol absorption and bile acid metabolism. Some gut bacteria help break down bile acids and influence cholesterol levels, impacting LDL (“bad” cholesterol) and HDL (“good” cholesterol) balance (Chi et al., 2022).
4. Blood Pressure Regulation
Short-chain fatty acids (SCFAs), such as butyrate, acetate, and propionate, are produced when beneficial gut bacteria ferment dietary fiber. SCFAs have been shown to improve blood vessel function, reduce inflammation, and lower blood pressure (Miller et al., 2022).
5. Insulin Sensitivity and Metabolic Health
Gut dysbiosis is linked to insulin resistance and metabolic syndrome, both of which increase the risk of cardiovascular disease. A diverse microbiome supports blood sugar regulation, reducing the likelihood of type 2 diabetes and obesity—two key risk factors for heart disease (Sonnenburg & Bäckhed, 2022).

How to Improve Gut Health for a Stronger Heart
Functional medicine emphasizes personalized interventions to restore gut balance and support cardiovascular health. Here are science-backed strategies to enhance the gut microbiome and protect the heart:
1. Increase Fiber Intake to Support Healthy Bacteria
A high-fiber diet promotes the growth of beneficial gut bacteria and enhances SCFA production, improving inflammation control and metabolic health.
- Soluble fiber: Found in oats, beans, flaxseeds, and berries, soluble fiber helps lower LDL cholesterol.
- Insoluble fiber: Found in vegetables, whole grains, and nuts, this fiber type supports gut motility and microbiome diversity.
- Recommended intake: 25-38 grams per day (Academy of Nutrition and Dietetics, 2023).
2. Eat Fermented and Probiotic-Rich Foods
Probiotic foods introduce beneficial bacteria into the gut, while prebiotic foods nourish existing microbes.
- Probiotic-rich foods: Yogurt, kefir, sauerkraut, kimchi, miso, and kombucha.
- Prebiotic foods: Garlic, onions, leeks, asparagus, bananas, and Jerusalem artichokes.
Probiotic supplementation can also be beneficial for individuals with gut dysbiosis or after antibiotic use (Ouwehand et al., 2022).
3. Reduce Processed Foods and Sugar Intake
A diet high in refined carbohydrates, added sugars, and ultra-processed foods promotes gut dysbiosis and inflammation. Reducing intake of these foods helps maintain a balanced gut microbiome and supports heart health.
- Excess sugar feeds pathogenic bacteria and yeast, increasing gut permeability (leaky gut), which allows inflammatory molecules to enter the bloodstream (Mu et al., 2022).
4. Manage Stress and Prioritize Sleep
Chronic stress negatively impacts the gut microbiome by altering microbial diversity and increasing inflammation. Functional medicine recommends stress-reducing techniques to support both gut and heart health:
- Mindfulness, meditation, and deep breathing exercises can lower cortisol levels and improve gut function (Smith et al., 2022).
- Quality sleep is essential for microbiome balance and cardiovascular recovery. Aim for 7-9 hours per night.
5. Exercise Regularly to Enhance Microbiome Diversity
Physical activity has been shown to positively influence gut bacteria diversity and reduce inflammation. Both aerobic exercise and resistance training contribute to cardiovascular and gut health (Monda et al., 2022).
- Aim for 150 minutes of moderate-intensity exercise per week (CDC, 2023).
6. Consider Targeted Supplements
- Probiotics: Support gut microbial balance.
- Prebiotics: Feed beneficial bacteria.
- Polyphenols: Found in green tea, berries, and dark chocolate, polyphenols improve gut health and cardiovascular function.
- Omega-3 fatty acids: Reduce gut and systemic inflammation.
Let’s Sum It Up
The gut microbiome plays a crucial role in cardiovascular health, influencing inflammation, cholesterol metabolism, blood pressure regulation, and overall metabolic function. A functional medicine approach emphasizes optimizing gut health through a high-fiber diet, fermented foods, stress management, and regular exercise.
By taking care of the gut, we can protect our hearts and improve long-term wellness. Small, sustainable lifestyle changes can have a profound impact on both gut balance and cardiovascular function, making heart health a truly holistic endeavor.

Written By: Roxanne Oliver, DNP, APRN, FNP-BC, CHHP
*The information contained in this post is for information only. It does not replace routine follow-up and/or care with a certified and licensed medical provider
References
Academy of Nutrition and Dietetics. (2023). Dietary fiber recommendations. Retrieved from https://www.eatright.org
Centers for Disease Control and Prevention. (2023). Physical activity and heart health. Retrieved from https://www.cdc.gov
Chi, X., Fan, Y., Zhang, Y., Zhang, H., & Wang, H. (2022). The role of gut microbiota in cholesterol metabolism and cardiovascular disease. Journal of Translational Medicine, 20(1), 1-13.
Koeth, R. A., Wang, Z., Levison, B. S., Buffa, J. A., Org, E., Sheehy, B. T., & Hazen, S. L. (2020). Intestinal microbiota metabolism of l-carnitine, a nutrient in red meat, promotes atherosclerosis. Nature Medicine, 19(5), 576-585.
Miller, M. A., Engen, P. A., Gorky, J., et al. (2022). Short-chain fatty acids and their role in gut and cardiovascular health. American Journal of Physiology-Gastrointestinal and Liver Physiology, 322(2), G156-G171.
Monda, V., Villano, I., Messina, A., Valenzano, A., Esposito, T., Moscatelli, F., & Monda, M. (2022). Exercise and gut microbiota: A new frontier for cardiovascular disease prevention. Frontiers in Physiology, 13, 821424.
Mu, Q., Tavella, V. J., & Luo, X. M. (2022). Role of gut microbiota in autoimmune diseases and its implications in cardiovascular health. Frontiers in Immunology, 13, 830690.
Tang, W. H. W., Li, D. Y., & Hazen, S. L. (2022). Dietary metabolism, the microbiome, and heart failure. Nature Reviews Cardiology, 19(3), 169-183.








