The Effects of Liver Disease on the Heart (and Vice Versa)

Did you know that the leading cause of death in patients with liver disease isn’t caused by the liver? It’s actually the heart (1)! But what does liver disease have to do with the heart? One simple way to explain this is through the circulatory system.

The circulatory system includes your heart and blood vessels, which connects all of your organs and body parts; this system does the important task of delivering oxygen and nutrients to cells as well as taking away waste (2). Therefore, the connection of the heart and liver is of utmost importance as the heart delivers oxygen to the liver and the liver rids your body of toxins via the circulatory system. Research has shown that heart health and liver health are linked, so disease in one organ can negatively affect the other. 

How Heart Failure and Cholesterol Affect the Liver

When we think of heart disease, we usually do not associate it with the liver or assume that a problem with the heart could affect the liver. Research has proven that liver inflammation can be caused by heart failure or other types of vascular issues (3); for example, if a heart is weakened by a disease, even a small decrease in its output can strain the liver. Nearly 20% of the heart's output blood flow goes directly to the liver, so when the heart is having issues, the liver can become stressed as well. Dr. Hamza El Hadi and his research associates found that up to 30% of patients with acute heart failure have developed liver damage (3). 

Even high cholesterol, a concern we normally associate with heart health, can affect the liver. Cholesterol is the result of a diet high in fats and sugars, and according to researchers at the Keck School of Medicine, “excess cholesterol accelerates damage of fatty liver disease” (4). In their study executed on mice, it was found that high cholesterol levels can make fatty liver disease worse and can increase inflammation and scarring of the liver (4). 

Fatty Liver and Cardiovascular Disease

Since heart disease can cause liver damage, how can liver disease affect the heart? Dr. El Hadi and his colleagues explained that when the liver isn’t functioning properly, it can affect one’s blood pressure and increase nitric oxide levels, which can negatively impact the heart. This can then cause stiffening of vessels, coronary artery disease, and irregular heart rate (3). 

Non-alcoholic fatty liver disease (NAFLD) plays a big role in heart health as well. According to the American Heart Association, out of 3.8 million adults with NAFLD, 400,000 suffer from heart failure (5). The buildup of fat in the liver can lead to the buildup of fat in the heart, resulting in heart damage and could ultimately lead to heart failure. Dr. Alan Kwan from the Smidt Heart Institute stated that “the liver plays a part in processing cholesterol, which can affect the heart” (6). In Kwan’s study, they didn’t find any definite links between NAFLD and cardiac issues, but insulin resistance, inflammation, and stress on both organs could be the culprit. Insulin resistance can create fat and plaque in the blood vessels because fat is not being properly transported throughout the body (3). With heart failure being the leading cause of death for those with NAFLD (6), it is not difficult to see the distressing link between both the liver and the heart. 

While these studies may be alarming, there are things we can do to be mindful of our health. Both the heart and liver affect one another greatly, so it is crucial to visit your doctor regularly and receive proper blood work to track your cholesterol and liver health. When it comes to treating both heart and liver disease, the best outcomes are from health and lifestyle changes. The American Heart Association details eight essential things to keep track of when developing towards a healthier lifestyle (7).

8 Essential Lifestyle Changes 

1. Eat whole foods, such as fruits, veggies, lean protein, nuts, and seeds, while avoiding trans fats and hydrogenated oils (both commonly found in fried foods and commercial baked goods).

2. Be physically active with at least 2.5 hours of moderate exercise or 75 minutes of vigorous activity a week.

3. Do not smoke, or quit smoking as soon as possible.

4. Get at least 7-9 hours of sleep every night.

5. Maintain a healthy weight.

6. Control and keep track of your cholesterol.

7. Manage your blood sugar levels.

8. Manage your blood pressure.

Get Your Liver on Track

If you need extra support with your liver health, try out The Plug Drink, which can in turn help with your heart health in the long run. We hope you implement these habits into your lifestyle so that both your liver and your heart can stay healthy and happy for many years to come!

Bibliography

1. de Roos A, Lamb HJ. Exploring the Interaction between Liver and Heart Disease. Radiology [Internet]. 2020 Aug 18;297(1):62-63. Available from: https://pubs.rsna.org/doi/full/10.1148/radiol.2020203112 

2. Circulatory system [Internet]. Victoria State Government: Better Health Channel. Available from: https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/circulatory-system

3. Hadi HE, Vincenzo AD, Vettor R, Rossato M. Relationship between Heart Disease and Liver Disease: A Two-Way Street. Cells [Internet]. 2020 Feb 28;9(3):567. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7140474/

4. Lewis W. High cholesterol leads to long-term liver scarring and immune cell dysfunction in lab study [Internet]. University of Southern California: Keck School of Medicine. 2022 Sept 16. Available from: https://keck.usc.edu/news/high-cholesterol-leads-to-long-term-liver-scarring-and-immune-cell-dysfunction-in-lab-study/#:~:text=Press%20Release-,High%20cholesterol%20leads%20to%20long 

5. Christensen T. Fatty liver disease may increase heart failure risk [Internet]. American Heart Association. 2022 Nov 16. Available from: https://www.heart.org/en/news/2022/11/16/fatty-liver-disease-may-increase-heart-failure-risk

6. Even Early Forms of Liver Disease Affect Heart Health, Cedar Sinai Study Finds [Internet]. Cedars Sinai. 2022 Dec 6. Available from: https://www.cedars-sinai.org/newsroom/even-early-forms-of-liver-disease-affect-heart-health-cedars-sinai-study-finds

7. Life’s Essential 8 [Internet]. American Heart Association Inc. Available from: https://www.heart.org/en/healthy-living/healthy-lifestyle/lifes-essential-8