Metabolic syndrome: what it is, symptoms, causes, treatments and diet

Metabolic syndrome: what it is, symptoms, causes, treatments and diet

Metabolic syndrome is a set of conditions (abdominal circumference, arterial hypertension, fasting blood glucose abnormalities, insulin resistance and dyslipidemia) that are the result of an alteration of the metabolism. It has several characteristics in common with obesity.

It is a syndrome involving the metabolism of fats and sugars and increases the risk of developing cardiovascular (heart attack) and cerebrovascular (stroke) diseases.

Diagnosis and treatment are the responsibility of the endocrinologist, even if, due to its transversal nature, the treatment may require the contribution of the nutritionist, cardiologist and neurologist.

The major problem associated with this syndrome is the increased risk of developing heart disease (2 times greater than in the general population) and diabetes (5 times greater).

What is Metabolic Syndrome?

Metabolic syndrome is defined as a complex clinical picture, determined by the simultaneous presence of three conditions: diabetes (which involves high insulin and insulin resistance), high blood pressure and obesity (with a marked tendency for fat to be deposited in the visceral level).

The name that is used today to indicate this complex pathology replaces the expressions used in the past:

  • Plurimetabolic syndrome.
  • Sindrome X.
  • Insulin resistance syndrome.
  • Deadly Quartet.

Sometimes the expression is used as a synonym for decompensation, dysmetabolism or dysfunction, terms which however have a different meaning.

We speak of metabolic decompensation when, in diabetic patients, a complication known as diabetic ketoacidosis occurs, which involves very high blood sugar, acidification of the blood and ketonemia (an analogue of what is called acetone in children).

“Disorder” is the word used generically to refer to a disease or pathological condition. “Metabolic disorders” has a similar meaning and refers generically to the disturbance of a balance.

Metabolic dysfunction is, on the other hand, an expression used as a synonym for metabolic syndrome in the definition of a disease, NAFLD (metabolic dysfunction associated with fatty liver).

If you are interested in the topic, discover our in-depth study on diabetes.

How does it manifest itself?

The underlying factors of the metabolic syndrome are the genetic predisposition to insulin resistance, being overweight and sedentary lifestyle.

This means that, in people predisposed to developing insulin resistance (genetic and therefore non-modifiable factor) who do not implement preventive behaviors such as to counteract a sedentary lifestyle (modifiable factor) and excess weight (modifiable factor), the risk of developing metabolic syndrome is higher than in the general population.

The characteristic features of this syndrome are:

  • accumulation of visceral fat.
  • Hypertension.
  • Fasting blood glucose changes.
  • Insulin resistance.
  • Low HDL cholesterol, high LDL cholesterol and high triglycerides.

Symptoms of the metabolic syndrome

Metabolic syndrome is a complex set of conditions in which it is difficult to distinguish precisely the symptoms, understood as manifestations, from the causes. This is the loss of a general balance, which can be triggered by different points (weight gain, food neglect, interruption of physical activity) to affect others, with a domino effect.

Below we indicate what, in general, are the relevant aspects.

Abdominal circumference

The development of metabolic syndrome depends not only on the amount of adipose tissue present in the body, but also on its distribution. This is an important difference from obesity, a disease with which it shares many aspects.

The risk of metabolic syndrome is greater if the fat is concentrated around the waist (visceral obesity), i.e. if the subject concerned has an “apple” conformation (i.e. with a high waist/hip ratio, generally associated with a lean mass/ relatively low body fat).

On the other hand, this risk is lower if the conformation is “pear-shaped”, i.e. with a low waist/hips ratio, which expresses a greater value than the lean mass/fat mass ratio.

Why is the accumulation of abdominal fat dangerous? Because the adipose tissue deposited there and which is also called “visceral fat” behaves like a real organ, which produces free fatty acids, which enter the bloodstream as such, accumulating in the liver and muscle.


High blood pressure damages the arteries. The wall of these vessels is in fact violently solicited by the blood, especially if subject to sudden changes in pressure.

Over time, lesions form in the vessel walls that increase the risk of rupture, resulting in bleeding: if the bleeding occurs in organs at risk, such as the brain (hemorrhagic stroke), it can be fatal.

Damage to the arterial wall also creates the conditions for atheromatous plaques to deposit: excess fat in the blood tends to deposit there, restricting the passage to the blood and causing episodes of ischemia. Even this phenomenon, which is described as endothelial dysfunction, can be life threatening.

If you are interested in the topic, discover our in-depth study on hypertension.

Fasting blood glucose changes

Normally blood sugar rises when we eat and the sugars contained in food are absorbed in the form of glucose in the blood. The release of insulin then allows glucose to enter the cells to be used as an energy source. This represents a mechanism of blood sugar regulation: I eat – blood sugar increases – insulin is released – glucose enters cells – blood sugar decreases.

Insulin resistance

The metabolism of sugars is based on the presence of a hormone called insulin. When we ingest a food that contains them, the blood sugar rises and the production of insulin is activated in the body, a substance that allows the sugars to enter the cells.

This phenomenon has two important consequences: the first is that sugars can thus be burned in cells to produce energy and carry out the metabolic reactions that allow them to survive, the second is that blood sugar levels never exceed a certain concentration.

An unbalanced diet rich in sugar tends to keep insulin levels always high. In some cases, when this stimulus is prolonged over time, the body becomes insensitive to the action of insulin, so to speak. This determines an impossibility to exploit sugars as energy sources and an increase in basal blood sugar, manifestations of the so-called insulin resistance syndrome.

This already sufficiently compromised framework joins a further series of conditions such as obstructive sleep apnea, chronic renal failure and polycystic ovary syndrome.

It must be said that excessive insulin values ​​for long periods of time also lead to an increased risk of other pathologies, first of all cancer. Indeed, insulin promotes cell proliferation and, when present in excess, can lead to a loss of the relative control factors which normally protect against the development of tumours.

If you are interested in the topic, discover our study on insulin resistance.


Loss of sugar metabolic balance leads to an increase in blood triglycerides and a reduction in good cholesterol (HDL).

Put together, these two elements describe a picture that is defined as Atherogenic Dyslipidemia, typical of the metabolic syndrome, but also of type 2 diabetes and other pathologies involving an increased risk of heart attack.

Causes of metabolic syndrome

More than causes, it is useful to talk about risk factors. In the case of the metabolic syndrome, in fact, there are numerous parameters that contribute to determining the imbalance and which interact with each other, progressively worsening the situation.

While some of these factors are modifiable, essentially those related to lifestyle, others are not.

Actually, we can’t do much about age: over 40 the risk increases and we have to deal with it. A similar reasoning can be made with genetics: some people have a genetic predisposition that makes them more susceptible to developing this condition.

However, we can act on everything that has to do with eating habits and lifestyles. A waist circumference that exceeds the measurements shown in the tables that take into account ethnicity and gender can be corrected with nutrition and exercise.

A sedentary lifestyle is another modifiable risk factor. As? With regular and constant physical activity over time and developing a mentality in which movement finds its place in everyday life.

Metabolic syndrome and diabetes

Metabolic syndrome increases the likelihood of developing diabetes 5 times compared to the general population.

Why does this happen? An unbalanced diet in favor of sugars and fats stimulates the production of insulin, which brings blood sugar back to normal. But if insulin levels remain permanently high, its effectiveness is paradoxically reduced. People who have a diet rich in sugars, therefore, especially after a certain age, will find it difficult to keep their blood sugar low.

This condition predisposes to the development of diabetes.


These two conditions share many aspects.

Excessive weight leads to the accumulation of adipose tissue,…