MOSCOW, November 12, Vladislav Strekopytov. The human body gives priority to protein consumption, and the reason for the obesity epidemic that is sweeping the world is the imbalance in proteins, fats and carbohydrates of modern high-tech products. Such conclusions were reached by famous Australian scientists, authors of the concept of “protein appetite”.
The power of protein
In the 1980s, University of Sydney biologists David Raubenheimer and Stephen Simpson studied the response of locusts to changes in food. It turned out that no matter what food the insects were given, they always consumed the same amount of protein. This is how the “protein lever” hypothesis arose.
They conducted experiments on monkeys, and then on humans – the results were the same. If there was little protein, the subjects continued to feel hungry, even though the food generally contained enough calories. It was assumed that the body is focused on a certain protein norm, so a person eats until he satisfies his “protein hunger”, while consuming a bunch of unnecessary fats and carbohydrates.
Satiety IndexThe “protein lever” hypothesis was developed in the work of Australian researcher and physician Suzanne Holt. She introduced the concept of the satiety index (sometimes called the satiety index) of products in relation to white bread, taken as 100 percent.
Participants in her studies were given equal-calorie servings of different foods. Then, for several hours, no food and feelings of hunger/fullness were recorded every 15 minutes using a special questionnaire. After the test, the volunteers were offered a buffet and watched what and how much each person ate.
The satiety rating was topped by potatoes, which contain appetite suppressants. Next are foods high in protein (meat, poultry, fish, milk, nuts) and fiber (fruits, vegetables, grains). Sweets, oddly enough, are at the bottom of the rating. This is explained by the abundance of fats in confectionery products. Therefore, chocolate, sweets, and cakes, by and large, do not satisfy hunger, but only burden the body with extra calories.
In a physical sense, the satiety index reflects the time period of feeling full in terms of one calorie of energy contained in the product. In principle, this parameter should be high for any hard-to-digest solid food that lingers in the stomach for a long time. A typical example is pasta. But experiments have shown that the brain of primates, including humans, when choosing a potential source of quick hunger satisfaction, gives preference to protein foods. This strategy, supported at the level of brain neurons, was called “protein priority”.
This gave rise to the thesis about “protein baits”, which can be used to control human eating behavior. Later they found out that fruits act in a similar way, as well as spicy, ultra-processed fast food products. Some, for example, chips, have very little protein, but the brain considers them as a “priority”. This feature is actively used by marketers in advertising.
The satiety index proposed by Holt is actively used by nutritionists: they try to select low-calorie foods that satisfy hunger well. You can get rid of excess weight without restricting yourself in food, but only by changing your diet.
The main thing is balance
In 2020, Raubenheimer and Simpson published a popular science book < u>book “Eat like animals. What nature teaches us about the science of healthy eating.”
“To get rid of excess weight, we need to take advantage of the intuitive experience of our smaller brothers,” they write they.
While observing monkeys, scientists noticed that no matter what the animals eat, they manage to maintain a daily calorie balance. About 25 percent is obtained from protein foods, the rest is carbohydrates and fats. In winter, when the body requires more energy, their share increases, but the amount of protein consumed in absolute terms does not change all year round.
This means that there are two types of appetite – protein and carbohydrate. When there is enough food, the animals eat a balanced diet. When food is scarce, appetites compete. The “priority” protein usually wins, but if there are no such products, carbohydrates are used – and the animals quickly get fat.
An interesting experiment was also conducted on humans. A group of volunteers was isolated three times (to ensure the accuracy of the result) for four days. For each, we selected a set of products with a unique ratio of proteins, fats and carbohydrates. You can eat as much as you want. Bottom line: Everyone consumed protein at about the same rate, and fat and carbohydrates depended on how much non-protein food they needed to eat to reach their protein goal.
In Pursuit of Profit
Raubenheimer and Simpson recently published an articlethat protein appetite is the main culprit in the global obesity epidemic. Modern food is high in calories but contains little protein. According to the Food and Agriculture Organization of the United Nations, protein consumption in the United States fell from 14 to 12.5 percent of the daily value between 1961 and 2000.
Scientists have calculated that to compensate for the lack of protein, you need to increase your caloric intake by 13 percent on average. At the same time, people give preference not just to carbohydrates, but to “protein baits” – carbohydrate foods with the flavor of meat: chips, instant noodles, crackers and other fast food. All this disrupts the mechanism of eating behavior built in the process of evolution.
“The attractiveness of fast food is determined by several factors,” explains endocrinologist and nutritionist, candidate of medical sciences Marina Sviridonova. “First of all, cheapness and convenience, the use of attractive, appetite-stimulating flavoring additives and a high content of ultra-processed carbohydrates and fats. It has been proven that such a combination causes in the brain, biochemical processes are similar to nicotine. In other words, it causes addiction.”
The main reason for the decrease in protein content in products is its relatively high cost compared to fats and carbohydrates. To make food cheaper, they remove protein, add fats, carbohydrates and enhance the taste with sugar, salt, and flavorings.
“The system of our appetites, which developed in the natural environment, has been exposed to high technologies that break our biology,” said Stephen Simpson in an interview with Knowable Magazine. “We need our appetites to work for ourselves and for health, and not for food manufacturers and drinks.”
September 28, 08:00
Ideal = individual
Nutrition experts note that the recently popular protein diet is also not a panacea. It has its drawbacks.
“Any diet with a long-term restriction of one or more food components cannot be useful if this is not due to a specific health condition,” emphasizes nutritionist, consultant for the Teledoctor24 service Maria Menshikova. “Excessive amounts of animal protein increases cholesterol in the blood, increases the level of highly toxic ammonia – a protein breakdown product, which triggers metabolic disorders in general. Low-protein diets, such as veganism, vegetarianism and their derivatives, lead to severe deficiencies of many nutrients, which is also not very healthy.”
“Protein is a component of food that gives a feeling of satiety,” explains Ksenia Selezneva, head of the department of dietetics at the European Medical Center (EMC), Candidate of Medical Sciences. “A person who loses weight with a high-protein diet does not feel hungry, he is comfortable. Weight at This is really reduced, but it is important to remember that long-term excess protein is fraught with complications – kidney stones, gout, etc. Everything needs balance.”
You need a balanced diet with an abundance of fiber and a small proportion of fats and carbohydrates. And the “protein lever” is just one of many causes of eating disorders.
“A key role in the obesity epidemic is played by the availability of high-calorie foods, a sedentary lifestyle and psychological factors – stress eating, eating for non-nutritive purposes, and so on,” Sviridonova lists. “Protein deficiency is not the main factor, but it can bring a few extra pounds.”< br />
“A person overeats for various reasons,” says Selezneva. “Including psychological ones. A hyperphagic reaction to stress is the easiest way calm down or reward yourself, eat something tasty. Bad eating habits ingrained in childhood and genetically determined characteristics, for example, a decreased feeling of satiety, also have an effect. The composition of the microbiota – the bacteria that live in the intestines – is also important. There are bacteria that help maintain normal weight. Obese people may not have them.”
Therefore, there is no universal diet. Nutrition should be balanced, varied and at the same time individual, suitable for a particular person.