Posted on Jan 29, 2021 181
It’s hard to lose weight. Incredibly, desperately hard. Most people who try to fight excess weight fail miserably, often even adding extra pounds to themselves. And it’s not just because they make amazingly delicious pizza or donuts these days. When you lose weight, you cause your body to fight back.
The fat you are trying to get rid of is an energy-rich super-substance, always ready to fuel your cells. If you have nothing to eat or your body needs more energy, stored fat comes to the rescue. From an evolutionary and survival standpoint, it is better to have enough than none! However, there is a rather common misconception. If you want to lose weight, eat less, and the extra fat is safely burned with exercise. After that, you just have to not overeat, and it will keep the body weight within the limits that you consider ideal.
The problem is that the body, regardless of its size, does not want to lose its untouchable reserve. So no matter how much you reduce your caloric intake, it will do anything to make it harder to lose weight. One of his lines of defense is hormones. Specifically, leptin, fat cells secrete which. The bigger they are, the more leptin they produce. When you lose weight, the levels of this hormone drop. Some areas of the brain, such as the hypothalamus, interpret its deficiency as malnutrition, so they send alarm signals. Their general sense comes down to the fact that it is necessary to eat something in order to restore the “lost” reserves.
Other organs also use hormones to complain to the brain about declining fuel. The stomach does this by increasing ghrelin levels. The pancreas secretes less insulin, which regulates blood sugar levels, and amylin, which signals satiety. So as soon as you reduce your caloric intake, a crazy set of alarm bells start going off in your head, making you run urgently to wherever there is something to eat. The brain, and this has been found through many scientific studies, responds to these hormonal changes by drawing your attention to all the surrounding food. It intensifies your sense of pleasure from it if you give in and eat something at that very moment.
Meanwhile, the rest of your body goes into energy-saving mode. So, for example, your muscles switch to a different fuel. Normally, when you’re not starving, they run on a mixture of fat and circulating glucose in the blood. But when you’re on a diet, they lean more on glucose, so they end up getting more energy from the food you consume rather than the fat reserves you’re trying to burn. Muscles use other tricks to conserve energy. The other tissues of the body also keep up with them.
The most unpleasant thing about all this is probably that the hormonal signals of “starvation” don’t stop when you give up your diet. This makes practical sense with leptin, since it depends on the amount of fat you have. However, other hormones, which are usually associated with food intake, are produced in insufficient amounts even after restoring a normal diet. And this can last for years. Thus, the body continues to behave as if it were starving - which probably explains the fact that people who have lost weight often put it back on again. And they can’t get their body out of energy-saving mode.
The smaller your body is, the less energy it needs to function properly. However, this is not a linear relationship. A lot of it depends on whether you were once heavier or lighter. This phenomenon was the subject of a high-profile study in which scientists followed former members of a television show devoted to weight loss for six years. Specifically, their resting metabolic rate was studied. Essentially, this is the minimum amount of energy the body needs to keep its cells working. They filmed the TV show for 30 weeks. During that time, the 14 participants lost an average of 58 pounds, and their resting metabolic rate decreased by about 610 calories per day. In the following years, however, they gained an average of 41 kilograms each, and their metabolic rates never returned to their previous levels. They ended up burning about 500 fewer calories per day than they should have. This means they will have to limit themselves even more when they try to lose weight next time.
It should be noted, however, that the strength of the body’s resistance to weight loss is often individual. Scientists continue to find out how much it is influenced by genetics, the foods we eat, and other factors. The general conclusion, however, is clear - the human body resists attempts to lose weight, so it is not surprising that so many people struggle unsuccessfully with being overweight.