Excess fat around the heart, known as pericardial fat or "fatty heart," is linked to a higher risk of heart failure, atrial fibrillation, and coronary artery disease1 . This risk exists even in people with a normal body mass index (BMI), highlighting the importance of fat distribution rather than just overall body weight2 . Understanding how heart fat affects health and ways to reduce it can help prevent serious cardiovascular problems.
Fatty Heart Explained
Epicardial adipose tissue (EAT) is the fat depot located directly around the heart, specifically between the myocardium (heart muscle) and the visceral pericardial layer3 . This fat is present in all individuals and serves as a source of energy and mechanical protection for the heart4 . However, EAT is not just a passive fat storage; it actively secretes bioactive molecules called adipokines and cytokines that influence heart health3 .
These secretions can promote inflammation and contribute to atherosclerosis, the buildup of plaques in arterial walls that increases the risk of cardiovascular events such as heart attacks3 . Increased pericardial adiposity is independently linked to adverse cardiovascular phenotypes, including changes in heart structure and function5 . The volume of this fat can be measured non-invasively using cardiac CT or MRI scans, providing a way to assess cardiovascular risk3 65.
Pericardial fat, sometimes called "fatty heart," is a type of visceral fat that surrounds the heart and upper chest. It produces inflammatory proteins that can speed up plaque buildup in coronary arteries, increasing the risk of heart attack and heart failure1 .
Causes of Heart Fat
The main contributors to increased fat around the heart are obesity and metabolic syndrome, which lead to greater pericardial and epicardial fat deposition7 6. There is a strong correlation between overall body fat and regional fat accumulation around the heart7 . Additionally, factors such as age, gender, and hormonal status influence pericardial fat volume. Older adults and postmenopausal women tend to have higher levels of pericardial fat8 6.
Obesity affects the hypothalamic–pituitary–adrenal (HPA) axis, which plays a role in fat distribution and increases visceral adipose tissue, including around the heart7 . Studies using MRI have shown that adrenal gland volume correlates positively with visceral fat compartments, including pericardial fat7 . This suggests that hormonal and metabolic changes in obesity contribute to fat accumulation near the heart.
- Obesity and metabolic syndrome increase pericardial fat deposition7 6.
- Age and hormonal changes, especially in postmenopausal women, raise pericardial fat volume8 6.
- Alterations in the HPA axis in obesity promote visceral fat accumulation7 .
- Adrenal gland volume is linked to regional fat deposits, including heart fat7 .
- Lifestyle and demographic factors also influence pericardial fat levels7 .
BMI and Heart Fat Risk
Pericardial fat is a strong predictor of cardiovascular risk independent of BMI and other general measures of adiposity6 9. While pericardial fat volume tends to increase with higher BMI and waist circumference, it can also be present in individuals with a normal BMI6 . This means that even people who appear to have a healthy weight may carry dangerous amounts of fat around their heart.
Studies involving large populations, such as the UK Biobank with over 42,000 participants, have confirmed that pericardial adiposity is independently associated with adverse cardiovascular outcomes, regardless of BMI6 . This highlights the importance of regional fat distribution over total body weight in assessing heart disease risk.
- Pericardial fat volume correlates with BMI but predicts heart risk independently6 9.
- People with normal BMI can still have high pericardial fat and increased cardiovascular risk6 .
- Pericardial fat is linked to myocardial infarction risk after adjusting for BMI9 .
- Large studies confirm pericardial fat’s role in cardiovascular disease beyond BMI effects6 .
- The relationship between BMI and pericardial fat requires further research6 .
Fatty heart is less about what you eat and more about how much you eat, emphasizing the role of overall calorie intake and lifestyle in heart fat accumulation10 .
Health Effects of Heart Fat
Excess pericardial fat is associated with increased risk of several serious heart conditions, including atrial fibrillation, heart failure, and coronary artery disease, independent of traditional risk factors like hypertension or cholesterol6 511. The fat releases pro-inflammatory cytokines that promote vascular inflammation and atherosclerosis3 . Its close anatomical proximity to the myocardium and coronary arteries allows these inflammatory molecules to directly affect heart muscle and blood vessels3 .
Mechanistically, pericardial fat can impair cardiac function by causing diastolic dysfunction (problems with the heart relaxing and filling with blood) and may also affect lung function due to mechanical effects12 13. Women with high pericardial fat have about double the risk of developing heart failure, while men have about a 53% increased risk1 2.
- Pericardial fat secretes inflammatory molecules that promote atherosclerosis3 .
- It is linked to atrial fibrillation and heart failure risk11 6.
- The fat can impair heart muscle relaxation and lung function12 13.
- Women with fatty hearts have a higher relative risk of heart failure than men1 2.
- Fatty heart increases risk regardless of overall body weight2 .
Underlying conditions, like obesity and high blood pressure, are known to increase the risk for heart failure, but these findings help investigators further study these associations, while potentially advancing research that helps explain sex-based differences in cardiovascular disease outcomes14 .
Heart Health Improvement Tips
Reducing pericardial fat and improving heart health involves lifestyle modifications that target visceral fat and overall cardiovascular risk. Key strategies include adopting a healthy diet, engaging in regular physical activity, quitting smoking, and managing stress4 .
💡 Did You Know?
Extra fat around the heart is linked to a greater chance of developing heart failure with preserved ejection fraction, a condition where the heart muscle becomes stiff14 .
A Mediterranean-style diet rich in fruits, vegetables, whole grains, lean proteins, legumes, olive oil, nuts, and seeds is associated with reduced cardiovascular risk4 . Avoiding processed foods, trans fats, added sugars, and excess sodium supports heart health. Regular aerobic exercise for at least 30 minutes daily helps reduce visceral fat, including pericardial fat1 .
Other important factors include maintaining adequate sleep duration and practicing stress management techniques such as meditation or yoga, which can improve cardiovascular outcomes4 . Healthcare providers can offer guidance on safe weight management and smoking cessation to further reduce risk4 .
- Follow a Mediterranean-style diet rich in whole, unprocessed foods4 .
- Exercise moderately for at least 30 minutes daily to reduce visceral fat1 .
- Avoid smoking and seek support for cessation4 .
- Manage stress through mind-body practices like meditation or yoga4 .
- Ensure adequate sleep to lower cardiovascular risk4 .
I've operated on many hearts throughout my career. I've seen enough of them to know that fatty heart can be a problem for all body types. No matter what the scale says, maintaining healthy habits in diet and exercise is the best way to lower your risk for heart disease10 .
Key Takeaways
- Pericardial fat, or fat around the heart, is an active fat depot that secretes inflammatory molecules promoting heart disease3 5.
- Obesity, age, and hormonal changes increase pericardial fat volume, but even people with normal BMI can have high heart fat and risk7 6.
- Pericardial fat is a stronger predictor of cardiovascular events than BMI alone, emphasizing the importance of fat distribution6 9.
- Excess heart fat raises the risk of heart failure, atrial fibrillation, and coronary artery disease, especially in women1 2.
- Lifestyle changes including diet, exercise, smoking cessation, stress management, and good sleep are essential to reduce heart fat and improve cardiovascular health4 1.
