What if I told you that there is a hidden danger inside your body, silently affecting your heart and blood vessels, and you can’t even see it? That danger is visceral fat. It is not the fat you can pinch or view in the mirror, but it is the type that is hidden deep inside your abdomen, surrounding your vital organs. Visceral fat is the fat stored within the abdominal cavity. It is not visible from the outside and can be present even in individuals who appear lean. This is why some individuals who appear slim may still have high levels of visceral fat, sometimes called “TOFI” ( Thin Outside, Fat Inside).

What makes visceral fat so harmful?

This type of fat is metabolically active, meaning it does not just exist passively. Instead, it actively interacts with the body’s systems, particularly the endocrine and immune systems.

Unlike other types of fat, visceral fat produces and releases inflammatory molecules, hormones, and substances that interfere with normal bodily functions, leading to negative health effects. This is one reason it is often referred to as “toxic fat” by health professionals.

How visceral fat impacts cardiovascular health

Visceral fat is harmful as it affects multiple systems and organs in the body, contributing to a variety of health conditions. However, one of its most significant impacts is on cardiovascular health, where it can lead to a range of issues that are major risk factors for cardiovascular disease.

  1. Inflammation: 

Visceral fat cells produce molecules called pro-inflammatory cytokines, such as interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α). These molecules trigger chronic, low-grade inflammation that spreads through the bloodstream, damaging the arterial walls. Over time, this contributes to arterial stiffening and atherosclerosis, a leading cause of heart attacks.

  1. Insulin Resistance: 

Excess visceral fat interferes with insulin’s ability to regulate blood sugar. The resulting insulin resistance raises blood glucose and insulin levels, damaging blood vessels and promoting type 2 diabetes. Additionally, insulin resistance can also increase VLDL cholesterol, which contributes to plaque build-up in arteries and heightens the risk of coronary artery disease.

  1. Raised Blood Pressure: 

The renin-angiotensin-aldosterone system (RAAS) plays a crucial role in regulating blood pressure and fluid balance. Visceral fat disrupts the balance of this system, leading to elevated levels of angiotensin. This causes blood vessels to constrict, resulting in high blood pressure (hypertension). It also contributes to arterial stiffness and impairs the vessels’ ability to relax, placing additional strain on the heart. 

  1. Unhealthy Cholesterol Levels: 

Fat deposits around the heart release inflammatory substances that further increase cardiovascular risk. Excess visceral fat is closely linked to a harmful lipid profile, known as atherogenic dyslipidaemia, which includes:

  • Elevated triglycerides
  • Low HDL (the “good” cholesterol)
  • Elevated LDL (the “bad” cholesterol)
  • Elevated total cholesterol
  • Elevated VLDL (very low-density lipoprotein). 

This combination of unhealthy lipids is particularly damaging to cardiovascular health. LDL cholesterol is more likely to penetrate the arterial walls, stick and contribute to plaque build-up, a key factor in the development of atherosclerosis. So, elevated LDL cholesterol levels further accelerate plaque formation in the arteries, increasing the risk of heart disease and other cardiovascular complications.

  1. Chronic Kidney Disease: 

Visceral fat is also associated with chronic kidney disease (CKD), a condition that further increases cardiovascular risk. Visceral fat can impair kidney function by promoting inflammation and altering the balance of important hormones and waste products. CKD often leads to higher blood pressure and abnormal lipid levels, both of which significantly raise the risk of developing cardiovascular disease.

The Impact on Heart Function:

  • Visceral fat damages blood vessels, restricting the heart’s ability to receive sufficient oxygen. When arteries become narrowed or clogged due to plaque build-up, the heart must work harder to pump blood. Additionally, high blood pressure, a common consequence of excess visceral fat, puts further strain on the heart. Over time, this chronic pressure can weaken the heart muscle, leading to hypertensive heart disease, which further raises the risk of heart failure.

How Much Visceral Fat is Too Much? 

You might be wondering, How do you know if you have too much visceral fat? Since it is not visible like subcutaneous fat, it can be hard to measure. However, there are a few signs and tools to help assess your risk:

1. Waist-to-Hip Ratio (WHR):

This is a simple method to gauge abdominal fat. For men, a WHR above 0.90, and for women, above 0.85, indicates a higher concentration of visceral fat, which increases the risk of cardiovascular disease. A larger waist relative to your hips suggests more fat around your organs.

2. Body Composition Analysis (BCA):

BCA provides a more detailed look at your body fat and muscle mass. Tools like bioelectrical impedance analysis (BIA) or DEXA scans can give you an accurate measurement of your visceral fat. These methods help assess how much of your total body fat is stored around your internal organs, giving a clearer picture of your heart health risks.

3. Body Mass Index (BMI):

While BMI is not a perfect measure, a score over 30 typically indicates obesity, which is often linked to higher levels of visceral fat. However, BMI does not distinguish between fat and muscle mass, so it is important to use this alongside other measurements for a more accurate assessment.

What Can Be Done?

It is worth noting that the risks it poses can be significantly reduced. Research shows that visceral fat responds well to:

  • Exercise regularly: Aim for 150 minutes of moderate activity weekly, plus resistance training to burn fat.
  • Eat a balanced diet: Focus on complex carbohydrates, high-quality protein, high fibre and healthy fats, especially omega-3 foods. Avoid processed foods and sugary drinks.
  • Sleep well and manage stress: Get 7–9 hours of quality sleep and use relaxation techniques like yoga or meditation.
  • Limit alcohol: Excess alcohol leads to fat around the abdomen. Cutting back helps reduce visceral fat.
  • Stay hydrated: Drink plenty of water to support metabolism and fat loss.
  • Quit smoking: Smoking increases cardiovascular risk and worsens the impact of visceral fat.
  • Monitor waist size: Keep track of your waist-to-hip ratio as an indicator of visceral fat.

Medical options: 

In some cases, medications such as GLP-1 agonists, liraglutide (Saxenda) and semaglutide (Wegovy, Ozempic, Rybelsus), have been shown in studies to reduce body weight, visceral adipose tissue, and inflammation while supporting cardiovascular health. These should only be considered under medical supervision.

Reducing visceral fat has been shown to lower inflammation, improve insulin sensitivity, reduce blood pressure, and improve cholesterol levels, all key to protecting cardiovascular health.