Medical expert of the article
New publications
Appetite
Last reviewed: 04.07.2025

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.

Appetite is a psychological desire to eat, and often concerns specific food products. Our life depends on what kind of hunger we experience: work, career, normal sensations in the stomach and intestines, and so on.
Therefore, appetite is very important for someone who wants to be a successful and sought-after person.
How does appetite affect life activity?
How much and how we eat depends on our appetite. It can be weak or brutal, the main thing is that it is there. If the appetite is strong, it cannot be suppressed by a simple effort of will. It is necessary to investigate the causes of increased appetite. Perhaps these are hormonal storms in the body or a deficiency of some hormones and a predominance of others? Perhaps these are foods with an increased content of substances that cause appetite?
If a person does not eat enough, then the level of endorphin hormones in the body decreases - the so-called hormones of joy. And then the person does not want to work, arrange his personal life, achieve anything. He becomes irritable and aggressive.
Consequences of prolonged fasting
If fasting lasts more than 24 hours, a man or woman (or child) may feel dizzy, have muscle weakness, and be unable to perform regular daily tasks. Brain function is impaired, simple tasks become inaccessible, and a person may faint in the most inappropriate place and at the most inappropriate time (for example, when receiving the Person of the Year award).
The person begins to lose weight rapidly and look bad, his skin is no longer soft and smooth, but rough and sore. His nails break, his hair splits and falls out. His teeth will not be healthy for a long time either: they crumble and fall out.
All this ends with the degeneration of the personality. The person is no longer interested in what he does, all his thoughts are occupied with food and control over kilograms, it is not even interesting to talk to him. Memory deteriorates, attention is scattered, the person becomes a crybaby and a bore. In general, you can say goodbye to the aesthetic moral appearance. This is what periodic malnutrition is.
Endogenous nutrition
Endogenous nutrition means internal. A person switches to it as soon as the body does not receive food from the outside or receives too little of it. And then we get the process of exhaustion: the reserves of subcutaneous fat are used up, then the muscle mass goes away. A person looks flabby, unkempt and this adds years to him.
When the body "eats" its own muscles and fats, it can live on. But internal food reserves are limited. Therefore, soon the body's tissues begin to actively undergo destructive processes. And that's it, it's all over, death is on the horizon. Because the body can't feed on its own muscles and fat forever. To live, you need food. And if this food appears, a person remains in the world of the living.
[ 7 ], [ 8 ], [ 9 ], [ 10 ], [ 11 ], [ 12 ]
The mechanism of appetite development
There are at least three chains that serve for saturation: appetite, eating tasty (or tasteless) food and the work of the digestive tract. As soon as you have a desire to eat, the salivary glands begin to work more actively. That is why people came up with the expression "drooling". This means that the stomach and intestines are ready to receive food and digest it. And also to utilize it.
But if we actively overeat, the body will also tell us about it with a feeling of satiety, burping, it is impossible to even look at the food - these are reflex reactions of the body to overeating. This is the body signaling us: "Leave those buns alone - I can no longer even look at them, much less chew them."
You should always pay attention to what you especially want to eat. Sour or salty or, conversely, sweet. This ingredient, then, is lacking in your body - it needs to be replenished, this will protect you from diseases. And you do not need to force yourself to eat the food that makes you feel sick - this means that the body has an excess of certain substances contained in this product. The body is the best prompter and assistant in choosing a menu.
If a person starts to want to eat after a long period of flu or cold, this is a reliable indication that he is recovering. Because the functions of a good appetite are also to provide a man or woman with a sufficient quality of life. Appetite consoles a person in grief, increases pleasure in joy and provides reliable protection against diseases at any age.
The role of appetite
It has not yet been fully revealed by science. But it is well known that appetite can regulate the work of all systems of the human body, improve its emotional, physical and psychological state, and also facilitate social contacts. This means that you need to listen to your appetite: if you are healthy, then eat what you want and refuse obligatory meals if it does not suit your soul.
But appetite needs to be controlled. That is why you should immediately consult an endocrinologist if your appetite is too small or too large, and constantly. Strong changes in appetite - from a strong desire to eat a lot to a complete unwillingness to look at food - should also alert you and make you consult a doctor.
Biological basis of appetite
There are biological bases of appetite according to the degree of attractiveness of individual types of food products. People get pleasure from specific food properties of products, their qualities, such as sweetness and fat content or sour or bitter taste. In the process of human evolution, preference for products with these properties can lead people to consume products that have special energy, for example, everyone knows the food value of carbohydrates, the energy value of fats.
Consequently, the survival value of these traits almost certainly continues to this day. Scientists recognize that most cultures have highly valued eating habits based on foods that are either sweet and fatty, or sour and bitter. And sometimes a combination of both - when appetite may be particularly intense.
How do these genetic traits based on the pleasant qualities of foods manifest themselves in brain processes? The attractiveness of food is an indirect signal of "rewarding yourself for something" on the way to the brain. These pathways for promoting various types of pleasure can be artificially stimulated by drugs and food.
[ 13 ], [ 14 ], [ 15 ], [ 16 ]
Research into the mechanisms of appetite
Through drug research, it has been discovered that neurochemical messengers are involved in the reward process, these messengers include dopamine, opioids, cannabinoids - these are molecules with their specific receptors. Research has also shown empirically that the areas of the brain that serve the most intense pleasures can be stimulated by food.
This means that the nutritional deficit indicated by low body weight can trigger the so-called reward systems to increase the enjoyment of foods. In practice, this would mean that people who have lost significant body weight will show increased interest in some foods that they enjoy, while ignoring others. This would mean that their appetite would increase at the sight of some foods they like, and decrease at the sight of foods they don’t like.
This can be seen as a useful biological mechanism, where appetite can be increased or decreased through the long-known phenomenon that appetite perceives an external stimulus as pleasant or not, depending on internal stimuli. This concept is based on the biological concept of pleasure.
High degree of appetite
However, another mechanism is also at work. This mechanism is based on the recognition that some people who rapidly gain weight and are obese have traits that motivate them to derive a high degree of pleasure from food. Consequently, foods with potent sensory properties are attractive objects for such people. And then the increased pleasure from eating can lead to overconsumption and increased weight.
There is clear evidence that obese women have a very high intake of sweet and fatty foods, which is why they consume significant amounts of them.
Other studies have shown that obese people prefer only fatty foods and respond to the taste of fat with pleasure. After eating, obese people eat the food that they find more pleasant than the food that they classify as tasteless. Therefore, a cake that is considered tasty is eaten again and again, and healthy, not tasteless carrots are ignored. Due to such biological properties of appetite, obesity tightly grips people in its clutches, and it is difficult to get out of them. Especially considering the abundance of products with pleasure-stimulating properties.
Appetite and the problem of choice
The activity of appetite depends on the properties of products. Science has found products that can increase appetite and suppress it. Taking these features into account, a person can control his appetite.
For many people, food is a cheap form of pleasure, available every day. Satiety implies a decrease in people's willingness to consume products. The question arises whether it is possible for the food industry to increase the taste of food products without weakening the feeling of satiety and vice versa. The balance between taste and satiety must be maintained, this is the essence of the interaction between hunger and satiety during food intake. That is, control over appetite.