Every endocrinologist who has ever consulted obese patients knows how difficult it is to find the cause of excess weight. Patients, in turn, are also perplexed as to why they suddenly began to gain weight. And indeed, out of 100 cases, maybe in 3–4 cases the cause will be determined.

Possible causes of excess weight

As practice shows, obesity in these cases is directly related to other endocrine and non-endocrine diseases and is therefore called secondary.

For example, in patients suffering from hypothyroidism, obesity is associated with a lack of thyroid hormones, which promote fat utilization. Constantly increased appetite (hyperphagia) and, accordingly, obesity may be a consequence of damage to certain areas of the brain due to any head injuries, inflammatory diseases or tumor processes.

In the remaining 96-97 cases of primary obesity, which develops regardless of anything, the cause may remain unclear. It remains obvious that this disease is based on a normal, evolutionarily determined, physiological phenomenon – the ability of adipose tissue cells to accumulate fat.

Why does the body stop burning fat?

Let’s try to figure out why the body does not burn fat as fuel, but begins to store it in fat depots?

From the position of the widespread theory of energy balance, according to which, weight remains stable if the amount of energy consumed by a person is equal to the amount expended, and it does not matter in what form the excess energy enters the body, in the form of fats, proteins or carbohydrates.

But as the results of special studies have shown, the energy effect from the breakdown of carbohydrates is higher than from the breakdown of fats, and the absorption of fats from food is a much simpler and energetically beneficial process than the formation of fat from carbohydrates. Therefore, when these substances enter the body for oxidation (i.e. combustion), it gives preference to carbohydrates, and for utilization (i.e. accumulation) – fats. A significant factor regulating appetite is the level of glucose in the blood and the state of glycogen depots in the liver and muscles.

Unlike carbohydrates, the potential for fat storage can reach several tens of kilograms. Studies have shown that patients who had a high-fat breakfast consumed more food than those who had a carbohydrate-rich breakfast. With free access to food, patients chose food containing more fat, which ultimately led to an increase in daily caloric intake and overeating.

Consequences of decreased ability to break down fats

Reduced ability to utilize fats and excess fat in the diet can lead to a decrease in tissue sensitivity to insulin (the pancreatic hormone that regulates glucose metabolism) and the development of metabolic syndrome (syndrome X), which subsequently determines the appearance of arterial hypertension, type 2 diabetes mellitus and cholesterol metabolism disorders.

The above provisions allowed JP. Flatt in 1988 hypothesized that excess fat intake, even within the normal daily caloric intake, can lead to an increase in fat mass.

The real hypothesis is that body weight remains constant if the amount of energy consumed as fat is equal to the amount of energy the body obtains from fat oxidation. If the fat content of food exceeds the ability to oxidize it, then excess fat will be stored in adipose tissue, regardless of the total amount of energy consumed.

Factors causing excess weight

The appearance of excess weight is due to two main factors

  1. amount of fat consumed;
  2. the body’s ability to oxidize fats.

As practice shows, increasing the proportion of fat consumed to 50% of daily calories leads to an increase in body weight in most people. But what’s interesting is that replacing part of the energy value of fats with carbohydrates, as a rule, does not entail weight gain. Thus, we can talk about the protective role of carbohydrates in the fight against extra pounds.

According to many scientists, the predisposition to the development of obesity is determined by the body’s reduced ability to oxidize fats. Often this decrease is genetically determined, which greatly complicates the task for patients and doctors

Leave a Reply