Why we overeat: 5 common reasons

The disease of the well-fed world, the scourge of the 21st century, the disease of office workers - it's all about obesity. We are used to thinking that this is a problem for the West. But according to the UN, Russia ranks 19th in the world in terms of the number of overweight citizens. According to the RAMS, 60% of women and 50% of men over 30 in our country are overweight, and 30% of the population is obese.

At the same time, global trends are disappointing: according to experts, the number of overweight people on the planet will reach one billion by 2025. One of the reasons for being overweight is overeating. Let's try to figure out what it is and why we eat so much.

What is overeating

Now three meals a day are considered the norm (about 2,500 kcal per day for men and 2,000 kcal for women). But does this mean that a person overeats if he eats 4-5 times a day?

Human eating behavior is determined by two mutually complementary hormones: ghrelin and leptin. Ghrelin is a peptide hormone that stimulates appetite, increases food intake and increases fat mass.

When the stomach is empty, ghrelin is produced and released into the bloodstream. These signals go to the hypothalamus, which is responsible for human eating behavior, where cells in the arcuate nucleus are activated. As a result, appetite is aroused, a feeling of hunger appears.

As the stomach fills, the fatty tissue hormone leptin is produced. It is a peptide hormone that regulates energy metabolism and suppresses appetite. Leptin interacts with nerve endings in the stomach walls and hypothalamic receptors, thereby signaling satiety to the brain.

This process is clearly shown in this video.

From a physiological point of view, overeating is a missing signal of satiety. But why do we ignore him? What are the reasons for overeating?

Reasons for overeating

Dopamine

The process of food absorption is associated with the production of dopamine. It is a neurotransmitter produced in the brain, as well as a hormone produced by the adrenal medulla and other tissues.

Dopamine is thought to be a chemical factor in the brain's reward system. At the same time, a professor at Stanford University, an expert in the study of the relationship between mental and physical states of a person, Kelly McGonigal is convinced that dopamine is responsible not for pleasure as such, but only for its anticipation.

Numerous proofs of this are given in her book “Willpower. How to develop and strengthen."

Nature has taken care that we do not starve. Evolution doesn't care about happiness, but it promises it so that we can fight for life. Therefore, the brain uses the expectation of happiness, and not the direct experience of it, so that we continue to hunt, collect, work and woo.

Kelly McGonigal

The sight and aroma of delicious food triggers a surge in dopamine. This is fine. The problem is that we live in a world where food is readily available. Each such outburst is a step towards overeating, and not a simple gratification of instinct. Seductive food is everywhere: on the most prominent shelves in stores, on street stalls, billboards. Dopamine makes us think, "I want this eclair!" Even when we are not hungry.

Worst of all, dopaminergic neurons get used to familiar rewards over time, even those they really like.

Scientists from the University of Texas at Austin have found that the degree of pleasure obtained from food correlates with the level of dopamine. When a person no longer experiences the same satisfaction from a favorite dish as before, it seems to him that he just needs to eat more.

Sugar and other flavor enhancers

Closely related to the dopamine trap is another reason for over-absorption of food - its taste.

David Kessler, M. D. and former head of the Federal Food and Drug Administration in the United States, has researched for years why the more sweet, salty, or fatty foods you eat, the more you want. He presented the results of his scientific research in the book "The End of Gluttony".

And although Kessler's theory of a global conspiracy is very controversial, the fact that the world food industry is actively using the formula "fat + salt + sugar = not just delicious, but super tasty food" is an indisputable fact.

A person overeats not only because it is delicious and impossible to break away, but also because sugar and other food additives block the satiety signal. So, scientists at Yale University found that fructose suppresses the activity of the parts of the brain that are responsible for appetite.

We miss the satiety signal, and it seems to us that we are still hungry.

Robert Sherwin endocrinologist

A similar opinion is shared by Robert Lustig, who noticed that fructose increases the body's resistance to leptin. It prevents it from entering the brain and makes you feel hungry.

Servings and Calories

The signal of satiety does not arrive immediately in the brain. A person, relying on his eyesight and prudence, eats until he empties the plate.

Professor Brian Wansink, head of the Food and Brand Research Lab at Cornell University, has been researching human eating behavior for many years. To this end, he conducted many interesting experiments.

In one of them, the subjects were seated at a table and offered to taste tomato soup. The catch was that pipes were brought to the bottom of the plates, which imperceptibly added soup to them. As a result, the subjects ate an average of 73% more soup than under normal conditions. Wansink explained this by the fact that for many people the words "full" and "empty plate" are synonyms.

Another experiment proving that large portions lead to overeating was carried out at the University of Michigan. The researchers placed two bowls of cookies (80 g each) in the break room, but one labeled "medium" and the other "large." It turned out that if a person chose cookies from the first bowl, they ate on average 12 g more than those who ate from a plate with “large” cookies. At the same time, the first firmly believed that they ate less.

Serving size is also related to the calorie content of the food. For example, vegetables are associated with healthy food, so many people tend to think that a standard serving is not enough to satisfy hunger. Have you noticed that dieters often order a double salad? The low calorie content of the dish creates the illusion of safety and leads to overeating.

Television

In the BBC documentary "How to feed children" (from the cycle "The Truth About Food") a demonstrative experiment was carried out, proving that while watching TV a person eats more than eating in silence.

13-year-old Rosie and her mother are overweight, despite the fact that the girl is constantly involved in sports, and the woman is at work all day. Their family's dinner takes place in the living room while watching TV.

The experiment took place in two stages. First, they baked pizza for Rosie and treated her to her during her favorite TV show. The girl ate 13 pieces. The next time Rosie was seated at the table, pizza was on the menu again. The girl ate 10 pieces, and her lunch lasted only 11 minutes.

What is happening on the TV screen distracts us, so we miss the signal of satiety. We can continue to eat for hours while we are passionate about the transfer.

Communication is an equally distracting factor. According to the professor of psychology John de Castro (John de Castro), during the conversation a person ceases to control the amount eaten. When you eat with someone alone, you eat 35% more than alone.

Family and environment

Among the anthropogenic factors of overeating are upbringing and cultural and household traditions.

"Until you eat everything, you won't go for a walk," the mother says to the child. Of course, she does not even think that by doing so she teaches him to overeat. Parents shape children's eating behavior. A person brought up in the spirit "who does not eat porridge will not grow up" is inclined to eat the entire portion, even when the body has informed about satiety.

In addition, according to researchers from the University of Pennsylvania, in families where parents are overweight, this problem is more often manifested in children. And it's not about genetics. Adults form the food environment in which the child grows up (cooking, serving portions), and also sets an example of eating behavior. If children see uncontrolled excessive consumption every day, then they consider this the norm.

Finally, one cannot fail to note the cultural and everyday traditions of society. So, Brian Wansink notes that Americans are used to filling their stomachs to capacity, but in Japan it is believed that it is better to leave the table when the stomach is only 80% full.

Also, if a person has ever starved in his life, for example, during a war, he will remember this every time he sits down at the table. The fear that food interruptions may recur prevents food from being left on the plate.