Since about 2011, researchers at the World Health Organization have begun to pay attention to the potential dangers of obesity. Since that time, it has already begun to increasingly acquire the features of an epidemic, and even children have become subject to obesity. A few years earlier, scientists discovered leptin - a hormone that is responsible for the feeling of satiety and can be used in the treatment of this disease.
Side effect of parabiosis studies
The history of the discovery of this hormone is associated with the research of the American scientist Hervey, who was interested in the processes of parabiosis. This process is a biological fusion in artificial conditions of two, and sometimes three animals. At the same time, they establish a common circulatory system, as well as lymph. Studies of this kind were necessary in order to study the interactions between hormones and spliced tissues.
The scientist was interested in a thorough description of all the functions of the hypothalamus. As is often the case in science, in the process, in the process of his research, the hormone of satiety of leptins was discovered. By 1998, about 600 articles had been published about this substance.
What are the functions of leptin in the body?
Translated from the ancient Greek language, its name means "slim, weak." However, the last word can not be called. After all, his role in the body is very large. Leptin is a hormone that belongs to a special category of substances called adipokines. Unlike other hormones, they are not produced by the organs of the endocrine system, but by adipose tissue. Adipokines in the body carry an information function. For example, leptin is able to transmit information to the hypothalamus about how much more or less fat has become in the body after eating. In turn, the hypothalamus regulates the amount of food consumed - it increases or decreases appetite.
The functions of leptin cannot be underestimated. It helps to suppress appetite, enhances the processes of thermogenesis, that is, the conversion of fats into energy and vice versa. Leptin is involved in the production of dopamine. In the female body, leptin affects the regularity of the menstrual cycle. It also improves the functioning of the entire female reproductive system as a whole. In addition, this peptide is involved in enhancing immunity.
Leptin works in close cooperation with the hypothalamus. When a person eats food, it is in the hypothalamus that signals, which cause a feeling of fullness, enter it. The relationship of leptin and dopamine was discovered by scientists not so long ago. Now there are suggestions that both excitement and the desire to eat something appear due to a lack of dopamine and leptin at the same time.
Leptin level and individual norms
Leptin indices may vary depending on affiliation with a particular age group. Also, the amount of leptin produced depends on gender. Before puberty, boys and girls have approximately the same amount of leptin. Then the situation changes dramatically. Since the female body always has more adipose tissue, the level of leptin with the onset of puberty in girls becomes higher. Also, estrogen affects this indicator.
Hormone composition
Leptin is a hormone that by its design is a peptide. It consists of 167 substances - amino acid residues. Most of this hormone is produced directly by fat cells. However, in addition to them, it can be produced by other types of cells. Namely, the placenta, mammary gland epithelium, gastric mucosa, skeletal muscle.
Elevated levels of leptin as a factor of coronary heart disease
However, both low and high levels of any hormone have a negative effect on the body. Leptin also acts. Hormone is elevated - what does this mean, and how can its amount adversely affect the body? First of all, high levels of leptin are a risk factor for various diseases. For example, increased leptin provokes an increase in longitudinal tissues and the deposition of various salts in the blood vessels, which leads to coronary artery disease.
Leptin and diabetes
Leptin imbalance is related to many diseases. Another dangerous consequence of a failure in his work is diabetes. The doctors recently discovered that the hormone leptin is directly related to this disease. What is this peptide responsible for in this case? In a healthy person, leptin increases the amount of glucose excreted by external organs. It also reduces the synthesis of insulin in the pancreas. When a large amount of leptin is in the body, this causes the production of a huge amount of insulin. Leptin also enhances the body's sensitivity to insulin. The hormone is elevated in those people who have a genetic predisposition or are prone to other risk factors that trigger diabetes.
The interaction of the peptide with another hormone
One of the main “partners” of leptin in the regulation of eating behavior is the “hunger hormone”. Leptin and ghrelin (the so-called this hormone) interact with each other, performing opposite functions. Ghrelin causes hunger, and is suppressed immediately after eating. Recently, it became known that this peptide also provokes weight gain in the long term. It is also produced in increased quantities during stressful situations. That is why, after a tense conversation, you really want something to eat.
How does a leptin behave with a diet. Hormone and feeling full
Unfortunately, a large number of diet fans follow the rules indicated in them without a proper assessment of all possible risks to the body. Most diets prescribe a reduced level of carbohydrate and fat intake, in the metabolism of which the hormone leptin takes an active part. What is responsible for each girl or woman who thoughtlessly decides to go on a rigid diet, for example, the well-known “Kremlin”? The most important risk is associated with metabolic disorders. After all, this diet involves a significant restriction in the intake of carbohydrates. In addition, fats are practically forbidden with it, and this can also lead to various endocrine disorders.
Many have heard that after a diet, weight can return, and even to a greater extent. This is due to the fact that the brain begins to respond much less to leptin. In other words, after this, the reaction of the hypothalamus to leptin becomes many times lower. Recently, a slimmer girl still constantly feels hunger, as a result of gaining even more weight. In addition, the brain, having received at the beginning of the diet a sufficient number of signals about the onset of "hungry times", gives the command to spend as little energy as possible. Therefore, sports and physical exercises become a real test - and most likely, such a girl will begin to lead a sedentary lifestyle.
Is there any sense in dieting?
Of course, in the process of losing weight, you can lose a large amount of body fat, and at the same time in a fairly short time. However, leptin also falls. Hormone raised - what does this mean for someone who is going to go on a diet? Most likely, its level will drop significantly in the first week. Fat deposits will also go away - but does it make sense if the brain loses its ability to feel hunger and is constantly in a state of “emergency”? With the onset of resistance to leptin, you can very easily gain weight in the first days after the end of the diet.
For people who are overweight or obese, it becomes increasingly difficult to lose weight over time. After all, their body is becoming less sensitive to leptin. With each meal they need to eat more, because their brain, which is almost not responding to satiety hormone, is sure that the body is starving. Leptin - the hormone of satiety - ceases to be such for them.
A way to balance leptin and ghrelin
The only way to get out of this vicious circle is to do aerobic exercise. This will help to gradually return the sensitivity of the hypothalamus to leptin. In turn, the hunger hormone ghrelin also comes back to normal. Studies have shown that even a half-hour aerobic exercise helps to significantly reduce the concentration of ghrelin in the blood. Thus, intense exercise helps both to get rid of excess fat and reduce appetite.
To better control the balance of leptin and ghrelin in the body, the researchers make the following recommendations. Firstly, you must observe the strict regime of the day - go to bed at about ten in the evening and get up at six in the morning. Secondly, you need to do exercises or other physical exercises every morning. Even a little physical exertion on an empty stomach, studies have shown, helps improve glucose and insulin sensitivity. And this is a good way to prevent diabetes.