Many people mistakenly believe that weight gain (and weight loss ) only related to calories and willpower.
However, the study of modern obesity does not agree, and scientists are increasingly accusing a type of hormone called leptin .
Being resistant to the effects of this hormone (called leptin resistance) is now thought to be the main cause of increased fat in humans .
In the paragraph above, a researcher and About obesity, explains everything you need to know about leptin and how it is related to obesity.
Familiarize yourself with Leptin, a "controlled" hormone that regulates body weight
Leptin is a hormone produced by body fat cells . It is often called "depression hormone" or "hungry hormone." Leptin's main goal lies in the brain, especially the place called (hypothalamus).
Leptin is said to tell the brain that we already have enough stored fat, we don't need to eat, and we can burn calories at normal speed .
It also has many other functions related to fertility, immunity, brain function and other functions .
However, the main role of leptin is long-term regulation of energy balance; calories that we eat and consume, and the amount of fat we store in our bodies .
The leptin system has evolved to keep us from starving or overeating, both of which make us less likely to survive in the natural environment.
Today, leptin is very effective in keeping us from starving. But something was broken in the mechanism that supposedly prevented us from eating too much.
Key thing: Leptin is a hormone produced by body fat cells. Its main role is to regulate the amount of calories we ingest and consume as well as body fat.
It is believed that leptin tells the brain that we do not need to eat
The way leptin works is relatively simple.
This hormone is produced by body fat cells. The more fat they carry, the more leptin they produce .
Leptin is transported by the blood into the brain, where it sends a signal to the hypothalamus (hypothalamus). This is the brain area that controls when and how much to eat .
Fat cells use leptin to "tell" the brain how much fat they carry. Many leptin tell the brain that they have a lot of stored fat, while low leptin levels tell the brain that fat reserves are low. We are at risk of starving now .
This diagram shows how leptin works:
We eat -> body fat rises -> leptin increases -> we eat less and burn more calories.
We don't eat -> lower body fat -> reduced leptin -> we eat more and burn less calories.
This type of system is known as a loop and similar control mechanisms for various physiological functions such as breathing, body temperature, blood pressure, etc.
Key thing: The main function of leptin is to send signals to the brain, "telling" how much fat is stored in the fat cells.
Eptin resistance may be the main biological abnormality in obesity
Obese people have a lot of fat in their fat cells.
Because fat cells produce leptin corresponding to their size, obese people also have very high leptin levels .
In a way that is considered leptin's way of working, these people should not eat, their brains should know that they already have a lot of energy reserves.
However, the problem lies in the leptin signal not working. There are many leptin floating around but the brain does not "see" it there .
This condition is called leptin resistance. Today people think this is The main biological abnormality in obese people .
When the brain does not receive the leptin signal, it misunderstands that the body is hungry even though its energy reserves are excessive.
This makes the brain change our physiological and behavioral functions to regain the fat that it thinks we are missing :
- Eat more: The brain thinks that we MUST eat to not starve.
- Reducing energy consumption: The brain thinks we need to conserve energy, so it makes us feel more lazy and makes us burn less calories when we rest.
In this way, eating more and exercising less is not the cause of weight gain, but that is of leptin resistance, a hormonal defect ( 16 ).
Most people cannot try to apply inhibition of awareness (will) to hunger signals caused by leptin.
Key thing: Obese people have high leptin levels, but leptin signals are inactive because of the condition called leptin resistance. Leptin resistance can cause hunger and reduce energy consumption.
Losing weight reduces leptin, so the brain tries to gain weight again
Most "diets" do not have good long-term results. This is a famous issue in weight loss research.
Diets are not so effective that whenever someone from obesity turns to lean, it is considered a reliable document.
The truth is that when it comes to weight loss, long-term success is an exception, NOT a routine. There are many reasons for this, but studies show that leptin may have a great relationship .
Weight loss reduces the amount of fat leading to a significant reduction in leptin levels, but the brain does not necessarily reverse leptin resistance.
Reduced levels of leptin cause hunger, increased appetite, decreased exercise motivation and reduced calories burned at rest .
Basically, the amount of leptin decreases, making the brain think it is hungry, so it triggers all the powerful mechanisms to regain lost fat and mistakes that it is protecting us from hunger.
In other words, the brain is active protect more fat, stronger biochemical effects force us to eat to regain lost weight.
Most dieters will get used to this. It is often easy to start losing weight, especially when there is a lot of motivation, but it is quickly starving so it is extremely important to reduce this exercise.
This is the main reason many people "waver" when dieting. They lose a significant amount of weight and immediately gain weight again (then they gain more weight).
Key thing: When reducing fat, leptin levels in humans decrease significantly. The brain understands that this is a sign that the person is hungry so it changes our biological and behavioral traits to help us recover the lost fat.
What is the cause of Leptin resistance?
According to Dr. Guyenet, some mechanisms have holes behind the identified leptin resistance. Include :
- Inflammation: The hypothesis of hypothalamus may be an important cause of leptin resistance in both animals and humans.
- Free fatty acids: Having free fatty acids in the blood can increase fat metabolism in the brain and interfere with the signaling of leptin.
- High leptin level: High levels of leptin are the primary cause of leptin resistance.
Almost all These factors are high in obese people. So this may be a vicious cycle in which obese people are getting fatter and getting more leptin resistance over time.
Key thing: Potential causes of leptin resistance include inflammation, elevated free fatty acids and high leptin levels. All three factors are high in obese people.
What does science know about reversing Leptin resistance?
The best way to know if you are resistant to leptin is to look in the mirror.
If your body has a lot of fat, especially in the abdomen, then you're almost certainly leptin resistant.
A key to prevent (or reverse) that leptin resistance is .
There are some things you can do as follows:
- Avoid processed foods: Pre-processed foods can affect intestinal integrity and cause inflammation .
- Eat soluble fiber: Eating soluble fiber can help improve intestinal health and fight obesity .
- Do exercise: Physical activity can help reverse leptin resistance .
- Sleep: Sleeplessness is associated with leptin problems .
- Reduce triglyceride levels: High blood triglyceride levels can prevent the transport of leptin from the blood into the brain . The best way to reduce triglycerides is to reduce the amount of carbohydrates .
- Eat more protein: Eat a lot the protein Can reduce weight naturally. There are many reasons and one of them may be the improvement of leptin's sensitivity (29).
Is there any method you find familiar? Incidentally these methods are related to health promotion.
Unfortunately, there is no simple way to do this. Eat fresh food , maintain a healthy intestinal tract, exercise, sleep well ... These are lifelong efforts that require a strong lifestyle change.
The main message to note
The cause of obesity is not due to greed, laziness or lack of will.
There are powerful biochemical factors that cause obesity, mainly due to changes in the environment, especially the diet in the West.
The truth is everywhere People using this diet are obese and chronic diseases will appear.
Not because this diet turns people into obesity but because it changes our biological characteristics in a way that changes our behavior.
Although the causes of obesity are complex and varied, leptin resistance is still the main cause of weight gain and it is difficult to reduce.
Leptin is a "hormone that takes control of" the mechanism that causes body fat.