The causes of obesity

Obesity is a problem that many people are troubled by now. The number of obese people is increasing, and the distribution of body fat is uniform without endocrine disorders. Often, there are some hereditary factors or some nutritional excesses that lead to obesity. And according to weight, it can be judged whether it is obesity symptoms. So we must also treat obesity well. Overweight can also lead to other body function decline.

Obesity is a very painful thing for patients. Many patients' general daily diet includes a lot of high-calorie foods, and excessive fat can lead to overnutrition, thereby promoting fat accumulation. Moreover, many people in daily life suffer from obesity symptoms due to genetic factors and social environmental factors.

Firstly, endogenous factors cause fat metabolism disorder and lead to obesity.

1. Genetic factors The occurrence of simple obesity in humans also has a certain genetic background. It is generally believed that human obesity belongs to polygenic inheritance, and genetics plays a role in predisposition in the pathogenesis. The formation of obesity is also related to lifestyle, feeding behavior, hobbies, insulin response, and the interaction of social and psychological factors.

2. Neuro-psychological factors There are two pairs of neural nuclei in the human hypothalamus related to feeding behavior. One pair is the ventromedial nucleus, also known as the satiety center; the other pair is the ventrolateral nucleus, also known as the hunger center. When the satiety center is excited, there is a sense of satiety and refusal to eat; when it is destroyed, appetite increases significantly. When the hunger center is excited, appetite is strong; when it is destroyed, there is aversion to food and refusal to eat. Under physiological conditions, it is in a dynamic balance state, regulating appetite within the normal range and maintaining normal weight. The blood-brain barrier at the hypothalamus is relatively weak, which makes it easy for various bioactive factors in the blood to migrate to this location, thereby affecting feeding behavior. These factors include glucose, free fatty acids, norepinephrine, dopamine, serotonin, insulin, and so on. In addition, mental factors often affect appetite. The function of the feeding center is controlled by the mental state. When the sympathetic nervous system is excited or the adrenergic nervous system is stimulated (especially when alpha receptors are dominant), appetite is suppressed. When the vagus nerve is excited and insulin secretion increases, appetite is often hyperactive.

3, Hyperinsulinemia In recent years, the role of hyperinsulinemia in the occurrence of obesity has attracted attention. Obesity often coexists with hyperinsulinemia, and the causal relationship between the two needs further investigation. However, it is generally believed that hyperinsulinemia causes obesity, and the insulin release in hyperinsulinemic obesity is about three times that of normal people.

Insulin has a significant effect on promoting fat accumulation and can be used as an indicator of obesity to some extent. The effect of insulin on promoting the increase of body fat is achieved through the following links: ① Promoting glucose entry into cells, thereby synthesizing neutral fat; ② Inhibiting the mobilization of fat in fat cells.

Overeating and hyperinsulinemia often coexist and are important factors in the occurrence and maintenance of obesity.

4, Abnormal brown adipose tissue Brown adipose tissue is a type of fat tissue that was only discovered in recent years, corresponding to the white adipose tissue mainly distributed under the skin and around the internal organs. Brown adipose tissue has a limited distribution range, only distributed in the interscapular region, the neck and back, armpits, mediastinum, and around the kidneys. The tissue appearance is light brown, and the cell volume changes relatively little.

White adipose tissue is a form of energy storage, where the body stores excess energy in the form of neutral fat. The volume of white adipose cells varies greatly with the release and storage of energy.

Brown adipose tissue is a heat-producing organ, that is, when the body eats or is stimulated by cold, the fat in the brown adipose cells is burned, thereby determining the level of the body's energy metabolism. The above two situations are respectively called eating-induced heat production and cold-induced heat production.

Brown adipose tissue, this heat-producing tissue, directly participates in the total regulation of body heat, dissipating excess body heat to the outside, making the body's energy metabolism tend to balance.

There are not many studies on brown adipose tissue in humans who are obese, but indeed, some patients with dysfunctional obesity that causes heat production can be observed.

5, Other Hormones are important factors in regulating fat metabolism, especially in the synthesis and mobilization of triglycerides, which are determined by hormones regulating enzymes. Insulin and prostaglandin E1 are the main hormones that promote fat synthesis and inhibit decomposition; catecholamines, glucagon, ACTH, MSH, TSH, GH, ADH, and adrenocortical hormones are hormones that promote fat decomposition and inhibit synthesis. If the former are secreted excessively and the latter are secreted less, it can cause an increase in fat synthesis, exceeding decomposition and leading to obesity. This group of endocrine factors are more closely related to secondary obesity.

Secondly, extrinsic factors are mainly due to overeating and insufficient physical activity.

The factors causing obesity can be mainly divided into intrinsic factors, mainly genetic and neurological factors, and factors caused by some diseases. There is a family history of genetic obesity, which will lead to this symptom. Neurological symptoms are also relatively easy to occur. Hormones are also an important factor in fat metabolism, and many external factors are caused by overeating or insufficient physical activity.