What is appetite and what are the centers in our body regulate it?
What is the appetite, probably, everyone knows, even the youngest children. This is when you want to eat! No, when you want to eat-it's not an appetite, but a feeling of hunger. We can eat herring with appetite, but at the same time absolutely without appetite to swallow broccoli and spinach. So what exactly is the appetite and what are the centers in our body regulate it?
We read the definition: "appetite is a feeling associated with the need for food, as well as the physiological mechanism that regulates the intake of nutrients." Can you imagine an evolutionary problem? It is not easy to create an organism that would react to the lack of food, but to construct a system that receives signals from each cell of the body about what it lacks. Otherwise, focusing only on the feeling of hunger, the biological organism will eat some unsuitable food and die.
The Great Russian scientist Ivan Petrovich Pavlov believed that appetite is gastric juice. Moreover, in order to make it stand out, you can just smell or imagine the food. And saturation occurs when the stomach is full. But look around. We would never have an epidemic of obesity if the body worked according to the "Pavlovo laws".
Today, there are seven theories of appetite regulation in science, and none of them fully explains what is happening. hat is why it is still not possible to create the perfect pill that would not give to gain excess weight.
The first theory is a mechanical one.
Appetite is regulated by the degree of stretching of the stomach.
The second theory is amino acid – static.
According to it, the excitability of neurons of the food center is determined by the content of amino acids in the blood. The food center in humans is found-a lateral nucleus of the hypothalamus.
Irritation of these nuclei leads to increased food consumption, and their destruction – to the refusal of food. These nuclei of the hypothalamus are called a hunger center or a food center. And amino acids are the building blocks of proteins. According to this theory, from different parts of our body we receive a signal: we need more amino acids – building blocks – a person starts to eat. A signal - "enough bricks" - stops food consumption.
The third theory is gluco – static.
The level of glucose in the blood drops-we feel hunger. Rising, then? full. But the theory doesn't work on cows, goats, sheep, and other ruminants that have no glucose absorbed from the digestive tract at all.
Lipo-static theory links appetite to fat consumption. Little fat-eat more, a lot – stop, throw this piece of fat... but it is rather a theory of fiction…
The fifth theory is hydration.
Connects appetite with the presence of water in the body. That's why they say: drink more, then less want to eat. Of course, the effect of water is, but still small.
Sixth - thermostatic.
It is based on the fact that warm-blooded animals must maintain the temperature of their bodies all the time. That is, they eat to prevent cooling and stop eating to avoid overheating.
And the seventh theory is metabolic.
Its meaning is that in the conveyor called "metabolism" should be a button to turn on and off the appetite. This theory is now being discussed vigorously.