20.10.2021

 Eating behaviour necessary to survive

Humans and animals eat food on an empty stomach for energy.

This desire is appetite, and when you are hungry, you start eating food. When you feel full, you stop eating.

This feeding behaviour is a natural behaviour for living things.

Causes of eating behaviour
Where is eating adjustment done?
Appetite regulator

• Glucose / free fatty acid
• stomach
• Eating experience
• State of mind and body

Causes of eating behaviour

Appetite regulators play a role in the causes of eating behaviour.

The desire to eat food is an important factor in initiating the feeding behaviours necessary to sustain life and continue living activities.

The desire for appetite is usually caused by hunger, but appetite is influenced by a variety of factors, as you may feel appetite even when you are not hungry.

Where is eating adjustment done?

Eating behaviour is caused by the feeling of hunger that "I am hungry".

Then, the feeling of fullness stops eating behaviour.

This instinctive feeding behaviour is regulated by the "feeding centre" located in the lateral area of ​​the diencephalic hypothalamus and the "satiety centre" located in the ventromedial nucleus.

When the feeding centre is stimulated and the satiety centre is suppressed, food is consumed.

On the contrary, when the satiety centre is stimulated and the feeding centre is suppressed, the intake stops, so the feeding centre and the satiety centre are in a contradictory relationship.

Experimental animals whose lateral field has been artificially destroyed to study ingestion behaviour become polyphasic and obese when they stop eating, lose weight, or starve to death while their ventromedial nucleus is destroyed.

Appetite regulator

The hypothalamus does not only have a neural appetite transmission mechanism that stimulates feeding behaviour like the feeding centre and satiety centre, but also a humoral transmission mechanism by science-sensitive neurons and brain amines and peptides in the brain. It has a great influence due to the inclusion of various factors such as regulation of chemically sensitive neurons by orexin.

Appetite-regulating factors also act as endogenous factors.

Glucose / free fatty acid

Glucose in the blood, that is, blood glucose and free fatty acids, regulates the feeding centre and satiety centre.

Free fatty acids are fatty acids produced by the breakdown of fat.

When the blood sugar level rises due to eating, the feeding centre is suppressed and the satiety centre is stimulated, causing a feeling of fullness.

In addition, when the blood sugar level decreases over time, the decomposition of fat progresses as an energy source, the amount of free fatty acids increases, and the feeding centre is stimulated.

stomach

When food enters the stomach, the stomach wall stretches.

After that, the parasympathetic nerve reacts to the change and stimulates the satiety centre, causing a feeling of satiety.

In addition, when the contents of the stomach are sent to the intestines, the stomach wall shrinks, and this time the sympathetic nerves react to stimulate the feeding centre, causing a feeling of hunger, which increases the appetite.

I'm sure there are many people who have had a stomachache when they are hungry.

The rumbling of the stomach is a sign of good health, as it promotes a feeling of hunger when the stomach is contracting.

Therefore, it contracts when the stomach is empty and stretches when food enters.

Eating experience

Appetite is also influenced by eating experience.

The information from the five senses introduced above and the memory and knowledge of the eating experience are integrated in the amygdala part of the brain to judge "delicious" or "not delicious".

At this time, the information that it is delicious is transmitted to the feeding centre, so the appetite is increased.

On the contrary, the information that it is not delicious is transmitted to the satiety centre, which means that you do not have an appetite.

And, depending on your childhood eating experience, it may affect your appetite because it remains a dietary habit until after you grow up.

State of mind and body

Appetite also changes depending on the physical and mental condition.

Maybe some people have experienced it, and some have heard of it?

Mental stress affects appetite, which increases or decreases depending on the degree of stress.

In addition, the effect on appetite changes depending on the physical condition, and most of them decline in the case of various illnesses.

English is my second language, so you may find incorrect sentences.

It would be great help if you leave a comment for me. 

Thank you for reading!