In the global debate about obesity, attention often focuses on total body weight, but modern science has begun to present a more complex and accurate picture. The problem does not lie only in the amount of fat, but in where it accumulates within the body.
Research in recent decades has shown that fat accumulated in the abdominal area, known as central obesity, is much more dangerous than fat distributed elsewhere.
This obesity is no longer just a matter of aesthetics or appearance, but today it is one of the most prominent drivers of what is known as cardiometabolic diseases, including high blood pressure, blood lipid disorders, type 2 diabetes, non-alcoholic fatty liver disease, heart disease and strokes.
A different type of fat
Central obesity refers to the accumulation of fat deep in the abdominal cavity, where it surrounds vital organs such as the liver, pancreas, and intestines. This fat is known as visceral fat, and it is radically different from the fat found under the skin.
While subcutaneous fat acts as an energy store, visceral fat acts like a hormonally active organ, secreting fatty acids, hormones, and inflammatory substances directly into the bloodstream.
Because of their proximity to vital organs, these substances quickly affect the body’s normal functions, which explains their strong association with diseases.
The hidden driver of heart and metabolic disease
Central obesity is at the heart of what is known as cardiometabolic dysfunction, serving as the starting point for a series of interconnected disorders affecting both metabolism and the cardiovascular system.
The first of these disorders is insulin resistance, as fatty acids released from visceral fat weaken the cells’ response to insulin, which hinders the regulation of blood sugar levels.
Over time, the pancreas fails to compensate, and sugar levels gradually rise and type 2 diabetes appears, often after years of silent changes. At the same time, central obesity causes a clear imbalance in blood fats, known as dyslipidemia.
This disorder is characterized by high triglycerides, low good cholesterol (HDL), and an increase in small, dense particles of harmful cholesterol (LDL), which are most capable of causing damage to the walls of the arteries. This pattern is considered one of the most dangerous factors that accelerate atherosclerosis.
When fat turns into high pressure
Another direct consequence of central obesity is high blood pressure, which is not an accidental event, but rather the result of the interaction of several biological mechanisms.
Visceral fat activates the sympathetic nervous system, which increases heart rate and leads to constriction of blood vessels. It also stimulates the renin-angiotensin-aldosterone system, which is a hormonal system that leads to the retention of sodium and water inside the body, which raises blood pressure.
In addition, the accumulation of fat around the kidneys can affect its function in regulating fluids, while chronic inflammation contributes to weakening the elasticity of blood vessels. Together, these factors lead to a continuous rise in blood pressure, with risks to the heart, brain, and kidneys.
Non-alcoholic liver
One of the most serious complications associated with central obesity is non-alcoholic fatty liver disease. With insulin resistance and increased flow of fatty acids from visceral fat, the liver begins to store them, leading to fat accumulation within it. Over time, this accumulation may develop into inflammation and damage to liver cells, and then to cirrhosis in advanced cases.
Today, fatty liver is viewed as the hepatic facet of heart and metabolic disease, due to its close association with insulin resistance, lipid disorders, and a higher risk of heart disease.
Chronic infections
All of these disorders share an underlying factor: chronic low-grade inflammation. Visceral fat constantly secretes inflammatory substances that spread throughout the body, causing gradual damage to blood vessels, exacerbating insulin resistance, disrupting the balance of fats, and contributing to raising blood pressure.
This silent inflammation is the hidden link between central obesity and overall cardiovascular disease.
Why is BMI not enough?
BMI (weight in kilograms divided by the square of height in metres) does not always reflect true health risks. A person of normal weight can have a high percentage of visceral fat, a condition sometimes known as normal-weight obesity.
This index also does not take into account the ratio of lean mass to fat mass (bodybuilders may have a high BMI without having high fat mass).
Therefore, experts recommend relying on other measurements such as waist circumference or waist-to-height ratio, which are more accurate in assessing the risk of heart and metabolic diseases.
A risk that can be avoided
Despite its seriousness, central obesity remains a condition that can be controlled. Visceral fat responds remarkably well to lifestyle changes. Regular physical activity, especially when combined with aerobic and strength training, helps reduce abdominal fat.
Following a diet rich in natural foods, fiber, and healthy fats also contributes to improving metabolic balance. Good sleep and reducing stress play an essential role in regulating hormones associated with fat accumulation.
Even simple changes can lead to significant improvements in blood pressure, fat balance, liver health, and heart risk.
