A lack of brown fat in humans makes it difficult to lose weight as you age. Brown adipose tissue in bodybuilding

Why is brown fat “good” and visceral fat dangerous to health? When is it time to sound the alarm and start watching your diet? How to get rid of “bad” fat? What can a large amount of fat in the body lead to? Together with nutritionist-endocrinologist Natalya Fadeeva, we are looking into these and other issues.

Natalya Fadeeva

There is nothing useless in the human body. Fat is also important hormonal organ. For example, during menopause in women, it partially takes over the function of the ovaries and produces sex hormones, which protects the woman from the development of osteoporosis (decreased density bone tissue) and fractures. Fat produces various hormonally active substances: resistin, adiponectin, leptin and others. Their functions in the body are being actively studied by scientists.

A person cannot live, much less reproduce, bear and feed a child without adipose tissue. There are genetic diseases in which a person practically does not have this tissue. Previously, such people could barely survive, but now medicine supports their viability.

White fat

This is the type that people first think of when they talk about fat. In another way, white fat is called white adipocytes - the cells that mainly make up adipose tissue. White fat is indeed white (or slightly yellowish) - due to the low density of mitochondria (permanent components of the cell, the source of energy of the cells) and small quantity blood vessels.

The main functions of white fat are to store energy (it is generally the largest source of energy in the body) and produce hormones. For example, the hormone adiponectin. It makes the liver and muscles sensitive to insulin, which means it reduces the risk of diabetes and heart disease. If a person gains weight, the production of adiponectin slows down or stops altogether - this can trigger the development of diseases. Fat also produces the hormone leptin - it regulates appetite and hunger. But this does not mean that the more white fat in the body, the better. Too much of it leads to leptin resistance. Result: constant feeling hunger and excess weight.

It is normal for a man's body to be 15-25% fat and a woman's body to be 15-30%. If the number exceeds the maximum, this indicates obesity - you need to reconsider your diet and think about training.

Natalya Fadeeva

White fat is the fat that is found under the skin, around the organs. As a rule, it accumulates in one droplet in the cytoplasm of the adipocyte cell. The main function of white fat is to store energy during periods of hunger.

Brown fat

The complete opposite of white fat - brown fat does not store energy, but helps to spend it. This type of fat owes its properties and color to close connection with mitochondria. Some scientists tend to classify brown fat more as muscle than as fat per se. If you activate this fat, it will begin to burn white fat.

Scientists have found that thin people have more brown fat than overweight people. Although there is little brown fat in the human body. For example, a person weighing 68 kilograms has 20-30 kilograms of fat. But only 500-800 grams of it is brown fat. And even this amount can burn from 300 to 500 calories per day - this is enough to regularly lose 450 grams of weight per week.

Scientists are working on a drug that would activate brown fat (the drug will help in the fight against obesity), but they still urge not to consider this a panacea and not to forget about sports and proper nutrition.

Natalya Fadeeva

Brown fat is fat that is located in the kidneys, back, shoulders, and neck. Its amount in the adult body is very small. In the body of a newborn, its amount can be much greater and reach 5% of body weight. Brown fat protects the child’s body from hypothermia, since its main function is thermogenesis (heat production).

In structure, brown fat differs from white fat in the large number of blood vessels and iron, which gives it its characteristic color. By increasing the amount of brown fat, you can speed up metabolism, increase energy expenditure and maintain normal body weight. You can increase its amount only by hardening the body - but the process starts only if you do this regularly, and from childhood.

It is brown fat that helps you lose weight - due to its thermogenetic effect, spending energy to keep warm.

Beige fat

During the course of research, scientists found that beige fat is a unique type of cell. They believe that white fat can be converted into beige fat, which means it will help get rid of excess weight. that catecholamines - hormones released during stress and colds - help transition the process of converting white fat to beige. . During physical activity muscles secrete special proteins that trigger this process.

Natalya Fadeeva

Beige fat is actually a transitional form of fat, from which, under the influence of conditions, external environment can form both white and brown fat. The latter will happen if the body is in low temperatures and needs additional thermogenesis. Beige fat was discovered not so long ago, and its role in the body is being actively studied.

Subcutaneous fat

Subcutaneous fat is the layer of fat that lies just under a person's skin and makes up 90% of all body fat. In many sports and medical centers you can measure the amount of this type of fat. Long-invented methods will help reduce its level - reduction fast carbohydrates and “empty” calories and regular high-intensity exercise.

Natalya Fadeeva

Subcutaneous fat protects the body from hypothermia, accumulates energy in case of hunger (cells can accumulate great amount energy), in women it is intended for pregnancy and breastfeeding, has shock-absorbing properties and is considered a hormonally active tissue.

The accumulation of subcutaneous fat depends on gender (women always have more than men), age (increases with age, decreases in old age) and eating habits (increases with physical inactivity and overeating). Excess accumulation subcutaneous fat in the thigh area in women increases the risk of disease reproductive system And varicose veins veins

It is subcutaneous fat that is blamed for cellulite, which is completely normal structure subcutaneous fat in women and depends on the amount of female sex hormones, structural features connective tissue among women. Cellulite does not require treatment at all from a medical point of view. The presence of cellulite is a female gender characteristic, and its absence indicates the predominance of male sex hormones.

Visceral fat

The most dangerous type of fat for health. Visceral fat is white fat that is found in the abdominal cavity around the organs, liver, pancreas, heart, and intestines. Researchers have discovered that visceral fat secretes retinol-binding protein 4, which increases insulin resistance. This, in turn, leads to glucose intolerance and type 2 diabetes.

Large amounts of visceral fat in the body have been linked to the development of breast cancer. colorectal cancer, heart disease, dementia. It is not entirely clear how dementia is linked to fat. Perhaps it has to do with the hormone leptin - produced by white fat - and its negative influence on the brain. , Candidate of Medical Sciences, Researcher research department at The Kaiser Permanente in Oakland, California, she identified the link between the presence of visceral fat and the development of dementia in a study where she analyzed data from more than 6,500 people.

To estimate the amount of visceral fat in the body, you need to determine your waist-to-hip ratio. Measure your waist and hips at their widest point. Then divide your waist circumference by your hip circumference. If the number is greater than 1.0 in men and 0.85 in women, then the fat level is too high.

Nutritionists recommend increasing the amount of unrefined foods, protein, unsaturated fatty acids, whole grain and fiber - their practice shows that this will help significantly reduce the level of visceral fat. It is also important to sleep 7-9 hours a day and exercise. , What effective method fight belly fat - do cardio regularly.

Natalya Fadeeva

Excessive accumulation of visceral fat (abdominal obesity, android obesity) leads to fat cells cannot cope with such an amount of fat (visceral fat cells cannot, unlike subcutaneous fat, accumulate fat in large quantities) and it enters the blood in the form of cholesterol, triglycerides and lipoproteins. This causes problems of cardio-vascular system(atherosclerosis, heart attacks, strokes), obesity of internal organs. And also fatty hepatosis, development metabolic syndromes, gout and other disorders.

You can get rid of “bad” fat if you follow the basic principles rational nutrition and move daily. For women, it is important that the waist circumference is no more than 82 centimeters, and for men - no more than 94. A significant increase in waist circumference - bad sign. He says there is more “bad” fat in the body than necessary. Prevention of abdominal (upper) type obesity - maintenance normal weight bodies throughout life, balanced diet and regular physical activity.

I’ll start with a quote from a biochemistry textbook edited by Severin: “Fat molecules in adipocytes are combined into large fat droplets that do not contain water, and therefore are the most compact form of storage of fuel molecules. It is estimated that if the energy stored in fats were stored in the form of highly hydrated glycogen molecules, a person’s body weight would increase by 14-15 kg.”

Another introductory quote: “The mechanism of switching energy storage mode to energy wasting mode may be a therapeutic target in the fight against obesity.”

Thermogenesis and thermogenin

Fat is an effective way to store energy. To lose fat, we need a way to spend/dissipate this excess energy. Mammals are lucky in that homeothermy (constant body temperature) gives us a mechanism needed to survive in cold environments by which our mitochondria can dissipate energy primarily from fats as heat. The so-called “cold thermogenesis” or non-shivering thermogenesis.

Uncoupling protein 1 (UCP1), also known as thermogenin, can dissipate energy.

Brown fat thermogenesis is associated with thermogenin (UCP1), a protein in the inner membrane of mitochondria.

UCP1 improves inner membrane conductance to H+, which dissipates the mitochondrial H+ gradient. This means that even with excess ATP, fats will continue to “burn” in the mitochondria, and the resulting energy will be dissipated as heat.

The path looks something like this:

Cold stress
Norepinephrine
Adrenergic stimulation of fat droplets in brown adipose tissue cells
Long-chain acids from the cell's fat droplet stimulate thermogenin
Thermogenin (UCP1) dissipates the H+ gradient
Fats are processed (even with excess ATP) into heat.

UCP1 is subsequently inhibited by cytosolic purine nucleotides. The mechanism by which fatty acid this is overcome remains unknown.

The mechanism of thermogenin activation is naturally more complex. We'll look at other factors a little later. The role of free fatty acids in the direct activation (join) of UCP1 was shown by Andriy Fedorenko and colleagues.

Figure 1. Free fatty acid from the fat droplet activates thermogenin (UCP1), which leads to the dissipation of energy in the form of heat.

The emergence of brown fat in the process of evolution and its role

Endogenous heat production provides mammals with a number of evolutionary advantages, but a significant part of the energy must be spent on maintaining body temperature in a colder environment. Most of the thermo-sensors in our body react to cold.

There are 2 main mechanisms of response to cold - shivering and non-shivering. Through shivering, when a cold stimulus causes muscles to contract rapidly, converting mechanical energy into heat. And thermogenesis without muscle contractions caused by burning fat for heat. This mechanism is more energy efficient. It involves brown fat and thermogenin.

The oldest traces of thermogenin date back to 400 million years BC. About 170 million years ago, monotremes separated from the mammalian lineage. They contain traces of UCP1, but UCP1-positive adipocytes have not been found in them to this day. A South American marsupial was found to have initial stage development of UCP1 mRNA. In the Australian fat-tailed marsupial mouse, a similarity of brown adipose tissue was found, but it did not have the adaptive function of cold-norepinephrine_stress-activation_UCP1. Afrotherium exhibits thermogenic brown fat at low temperatures environment. In the Hottentot golden mole, brown fat thermogenesis is considered the main adaptive mechanism to cold. The evolutionary path of thermogenic brown fat is schematically shown in the figure below.

Figure 2. Emergence of cold-activated thermogenic brown fat during mammalian evolution.

Types of adipose tissue

Figure 3. Adipose tissue types and plasticity in response to temperature changes.A) Main morphological and functional differences between brown, beige and white adipocytes. B) Anatomical location of the main deposits of adipose tissue. Brown:iBAT – interscapular brown;sBAT – subscapular brown;cBAT – cervical; Subcutaneous white:asWAT – anterior subcutaneous white;ingWAT – inguinal; visceral fat:mWAT – mesenteric;rWAT – retroperitoneal;pgWAT -perigonadal. The dotted line is the peritoneum. C) Brown/white fat model inC57BL6 male mice 13 weeks old. In the thermoneutral zone (30 degrees, 4 weeks), brown adipocytes began to resemble white ones. From 22 degrees brown fat became active. With a progressive decrease in temperature from 22 to 6 degrees, subcutaneous white fat changes and begins to resemble brown fat. Visceral fat is generally resistant to temperature influences.

Brown adipose tissue (BAT)

Brown adipose tissue is characterized by a large number of mitochondria, a large number of small fat droplets, and high expression of uncoupling protein 1 (UCP1). Without external stimulation, brown fat is less active due to purine nucleotides. Cold stress leads to both activation of UCP1 and lipolysis, providing fuel for thermogenesis needs. Active brown fat imports glucose and fatty acids to provide additional fuel to support thermogenesis.

In humans and mice, brown adipocytes are concentrated in areas of high blood flow. The largest deposits are in the interscapular, subscapular and cervical areas. Small reserves in the area of ​​the renal scar and aorta. Post-mortem analysis of people showed that there are deposits of brown fat around carotid artery. Until 2007, science denied the presence of brown fat in adults. There is an inverse correlation between the amount/activity of brown fat and body mass index (BMI).

BAT (brown adipose tissue) can expand due to the number of cells (hyperplasia) and due to the size of the cells (hypertrophy). Hypertrophy largely depends on the environment. Without temperature stress, brown fat is less metabolically active and accumulates fats in one fat globule. But even with a slight decrease in temperature, it has a more familiar multi-chamber morphology of fat droplets. Cold reduces BAT size through lipolysis and beta-oxidation, but prolonged cold exposure can increase brown fat mass by activating adipocyte precursor proliferation and differentiation mechanisms, i.e., increasing the number of adipocytes.

Figure 4. Distribution of brown adipose tissue in adults (left) and infants (right)

White adipose tissue (WAT)

White fat is the most common type of adipocyte, containing one large fat droplet. The main function of white adipocytes is to store “fuel” and release adipokines (such as leptin, adiponectin) to regulate energy homeostasis. The expansion of white fat (including in obesity) protects organs and muscles from lipotoxicity. WAT is usually divided into subcutaneous and visceral. An excess of the latter is associated with metabolic diseases, while an excess of subcutaneous is considered protective. White fat can expand in both cell size and quantity. The main sites of subcutaneous and visceral white fat deposition are marked in Figure 3.

Beige fat(brite, brown-in-white)

There is some debate about the origin of beige fat. Whether this is a form of white fat or a completely different form of fat that is activated by an external stimulus is important from a pharmaceutical point of view, but not from a practical point of view.

"Browning" occurs during energetic stress. Our most obvious example is hardening, when the energy from muscle contraction (shivering) is not enough to maintain body temperature. But browning also occurs with other external stress: cancer cachexia, serious burns, exercise and so on.

Thermogenin (UCP1) is activated along the above chain. Cells begin to store fat and burn it to produce heat. More mitochondria appear and there are more fat droplets. Visceral fat is much more susceptible to “browning” than subcutaneous white fat.

Fat cycle

It is important to understand that it is under stress (for example, cold) that brown fat becomes thermogenic, white fat turns into beige (bright). In the absence of a stimulus, brown and beige fat begin to resemble white fat.

Figures 5. Conversions of fat types into each other in the presence/absence of an external stimulus (in particular cold).

Factors influencing the activation of brown and beige fat

Endogenous factors directly related to cold

Figure 6. Endogenous factors influencing brown/beige fat activation. Neurons and macrophages secrete noadrenaline; the heart secretes natriuretic peptides; liver and brown fat secreteFGF21; muscles secrete irisin; thyroid T4, which is converted to T3; brown fat secretesbmp8b andvegf, which enhances thermogenic function in an autocrine manner. Orexin andBmp7 promotes brown fat formation, although its cellular source is unknown;

These and other factors are more important for researchers looking for ways to pharmaceutically activate brown fat. Trials of β3-AR agonists have not yet yielded the expected results in humans. For us, the most important activator is cold, which, among other things, promotes the growth of blood vessels in adipose tissue, which promotes oxygen delivery and heat exchange.

For further work with the literature, it is a good idea to remember the transcript coactivator PCG-1α, which is directly related to mitochondrial biogenesis and is the central transcript effector of adrenergic (stress) activation of thermogenic adipocytes.

PPAR-γ receptors, which play a role in the adipogenic mechanism.

FGF21 factor will be found in the literature on metabolic health (diabetes in particular), this factor affects the improvement of insulin sensitivity, glucose uptake by peripheral cells, and weight loss.

Natriuretic peptides reduce blood volume and pressure, promote sodium excretion by the kidneys, and promote lipolysis. It is logical to assume that there must be a dialogue between cardiomyocytes and adipose tissue to protect the heart muscle during cold weather.

Those who are very concerned should google the factors KLF11, PRDM16, EBF2, EWS/YBX1/BMP7 axis, IRF4, ZFP516 or read about them at the link below.

All of the above factors are modulated by cold as well as pharmacological intervention. Therefore, from a practical point of view, it is not worth spending too much time on them.

Exogenous factors that complement cold well

Sympathetic stimulation of β3-adrenergic receptors is more important for the conversion of white fat to beige (or activation of beige) than for brown fat.

• Capsaicin ( hot pepper) – stimulation of β3-AR;
• Fish oil (omega-3);
• Physical exercise;
• High fat diet.

Hot peppers and stress are additional stress, with this at the level of formal logic everything is clear.

Kim and colleagues write that fish oil activates the sympathetic nervous system, increases oxygen consumption (read fat oxidation), and rectal temperature with activation of β3-AR and thermogenin (UCP1). As a meat lover, I want to note that the fats of grass-fed beef (read DHA, omega-3) and grain-fed beef (omega-6, unsaturated fatty acids) are very different not only in taste, but also in color. When grass-fed, the fat is brown, and while texturally it is not as tender as its less healthy counterpart, it is much tastier. Grain-fed fat is white.

I don’t want to consider pharmacological exogenous agents for two reasons: the scientific side has not yet come to guaranteed working solutions and there are proven and effective means, which do not require farm support.

The ketogenic diet and brown fat

Kirill Stasevich

Doctors have every reason to believe that being overweight is not a good thing. As a rule, a whole range of disorders are associated with increased body weight: from cardiovascular to metabolic. And the number of people with one form or another of obesity is constantly growing.

How can you keep your weight within normal limits? The answer, it would seem, could not be simpler - eat less, move more. No one doubts the effectiveness of these remedies, but they do not help everyone. Some people have metabolic characteristics such that fat accumulates with any diet. Sometimes we simply cannot resist the feeling of hunger: the brain requires calories without regard to excess weight. It is also not always possible to follow instructions regarding physical activity, especially for city residents.

Therefore, obesity has become one of the most studied topics in modern medicine, and the efforts of many researchers are aimed at finding a remedy that would help prevent fat accumulation. You can, for example, try to change eating behavior through the brain and neuroendocrine system. Another way to prevent fat accumulation is by targeting intestinal microflora, since it largely depends on it what from food will be absorbed into the blood and what not. Finally, excess lipids can simply be burned, that is, they can be broken down in some metabolic processes.

Meanwhile, fat is different from fat. What is deposited on the buttocks and waist is white adipose tissue, consisting primarily of white adipocytes (fat cells). Their function is to store a variety of lipids, and they look like a huge drop of fat. They have cytoplasm, nucleus and other components of the cell, but they huddle somewhere between the lipid mass and the membrane. Brown fat cells look different: they have several fat droplets, and in the cytoplasm there are a lot of mitochondria, which, thanks to iron-containing proteins, give the cells a darker, brown color.

From a biochemical point of view, brown fat cells are arranged in a senseless way at first glance. In their mitochondria, the connection between the oxidation of organic molecules (that is, lipids) and the synthesis of energy molecules ATP is broken. As is known, during the oxidation of molecules in mitochondria, a proton gradient is created on their internal membranes: there are more protons on one side of the membrane than on the other. This gradient is necessary for the enzyme built into the membrane to work for the synthesis of ATP: the energy stored in chemical bonds ATP is easily released and used in the vast majority of molecular processes in the cell. But in brown fat, the energy from oxidized products is almost not stored in ATP. But it is not wasted either, but goes into warmth.

All cells, to one degree or another, allow some portion of the energy they receive to leak into heat, but brown fat cells are specialized for this very function - creating heat from stored lipids. It is easy to guess that brown adipocytes serve as an important element of the thermoregulation system in warm-blooded animals. In fact, zoologists have long noticed that brown fat is especially developed in animals that hibernate. “Sleeping” animals cannot maintain body temperature using other mechanisms, such as shivering, and brown fat comes in handy.

Brown fat also protects infants from hypothermia - in them it constitutes up to 5% of body weight. In adults, as was believed until recently, brown adipocytes cease to perform their function, lose mitochondria and turn into something like ordinary white fat cells.

However, a few years ago, brown fat was also found in adults. It turned out that some part of it remains in the area of ​​the neck, shoulders and upper part chest. Moreover, it turned out that the amount of brown fat in adults increases in the cold, which is understandable, because brown fat is needed specifically for heating.

And since the “furnace” of brown fat works on lipids, the idea arose: could it be used to get rid of excess weight? But then we need some kind of “switch” that would activate brown adipose tissue when needed. To realize this idea, it is necessary, firstly, to understand the molecular and cellular mechanisms that ensure the appearance of brown fat in the body, and secondly, to make sure that it really helps against obesity and related metabolic problems.

Although brown fat cells were found not only in special “depots”, but also in the thickness of white fat, it was believed that they still had their own special precursors, which then developed into brown adipocytes. However, researchers from ETH Zurich have found that white fat and brown fat can directly convert into each other. The experiments were carried out on mice in which individual white fat cells were monitored: when the temperature decreased, these cells “turned brown”, and when the temperature increased, they “turned white.” It turns out that brown fat can be formed directly from white fat.

Brown adipose tissue is densely permeated with blood vessels; they not only bring her fuel, but also take heat with them. It was even possible to find nerve cells that give a signal for the breakdown of fats - they turned out to be some neurons of the hypothalamus. They controlled specifically the metabolic activity of brown fat cells. That is, appetite and food consumption remained the same, but in the brown fat “furnace” it was burned large quantity calories.

The brain can control brown fat not only through neural signals itself, but also through neuropeptide hormones called orexins. These neuropeptides are synthesized again in the hypothalamus, participate in the regulation of sleep-wake cycles and affect energy metabolism and appetite. It turned out that orexins directly act on white fat cells, promoting their transformation into brown adipocytes. (It is possible that the matter is not limited to direct influence alone, since orexins are included in complex system several neuropeptides that control metabolism and can act on brown fat through their “influencing agents.”) If the orexin genes were turned off in mice, the animals gained weight even with a moderate diet.

However, you should not think that brown fat is under the care of just a couple of neuropeptides and a group of nerve cells. The most active participant in the transformation of one adipose tissue into another takes the immune system. Several years ago, researchers from the University of California, San Francisco (USA) discovered that macrophages present in white fat cause fat cells to turn brown when the temperature drops. Macrophages are usually spoken of as “cleaner” cells that eliminate the consequences of “immune wars”, and their active role in metabolism became clear only recently. Under the influence of special signaling proteins, macrophages force adipose tissue to burn its reserves. And just recently it was possible to link the immune signals that control macrophages with muscle function. During physical exercise and again when the ambient temperature drops, a special hormone (called meteorin-like hormone) is released from the muscles, which, through the immune signaling proteins interleukins, acts on macrophages located in adipose tissue, and then everything unfolds according to the scenario described above.

Deciphering the mechanisms that control brown fat usually involves searching for molecular “magic buttons”—regulatory proteins that can be used to activate the appearance of new brown cells or enhance their activity. Thus, recently researchers from Virginia Commonwealth University (USA) published an article in which they proposed the enzyme Tyk2 kinase to play the role of the brown fat switch. Until now, this enzyme has been studied as one of the promising anticancer proteins. (It may be recalled here that obesity often develops along with oncological diseases.) There are many such examples; reports of brown fat activator proteins appear regularly. Naturally, in each such work their effect on excess weight is tested. So far, anything that activates brown fat helps with excess weight get rid of. But does brown fat help reverse the metabolic problems that accompany obesity?

Researchers from the Dana-Farber Cancer Institute (USA) answered this question in the affirmative. They found a protein that links heat-burning calories to inflammation that begins in overgrown fat tissue. It is inflammation that is believed to provoke resistance of tissues and organs to insulin, which is a direct path to type 2 diabetes. It turned out that the TRPV4 protein, contained in white adipocytes, interferes with fat burning and promotes inflammatory processes in adipose tissue. If the synthesis of TRPV4 was suppressed, then there was no obesity or inflammation in the experimental animals, although they ate a high-calorie diet. fatty foods. In fact, other studies have also noted a connection between the activation of brown fat and the disappearance of signs of diabetes, but it was necessary to find a specific molecular link. It turned out to be TRPV4. However, it must be taken into account that research of this kind is not limited to just one link, and usually molecular biologists extract a whole signal chain by catching a link, each member of which can become a target for drugs.

Basically, such experiments are carried out on mice, so it would be reasonable to ask the question to what extent the results obtained can be extrapolated to humans. But literally in July of this year, an article was published in the magazine “Diabetes” in which employees medical department University of Texas at Galveston (USA) write about a clear connection between the amount of brown fat in a person, the level of glucose in the blood and the response of cells to insulin. The more active brown fat was, the more it was, the more calories were burned and the more actively glucose was absorbed from the blood into tissue cells. So brown fat could really be a good medical tool in the fight against obesity and diabetes, and it is not in vain that scientists are looking for a means with which they can quickly and effectively activate brown adipose tissue.

Most of these searches are aimed at target molecules involved in the management of brown fat. Different approaches differ here in effectiveness and likelihood of side effects. For example, employees of the biotechnology company Genetech claim that they can activate brown adipocytes and normalize metabolism with just one injection of antibodies that activate cellular receptors for the hormone FGF21 (fibroblast growth factor 21). In diabetic mice that received the injection, their glucose levels remained normal for a whole month, and the mice themselves lost 10% weight. However, these antibodies have so far only been tested on animals. On the other hand, researchers from Cambridge (UK) believe that preference should be given to “their” protein called BMP8B, which not only activates brown fat, but does it very specifically - that is, by acting on BMP8B with some drug, we almost We do not risk affecting another molecular cellular process. It is also worth mentioning recently open hormone irisin - it saves from obesity and diabetes, turning white fat into brown, and at the same time promotes the growth muscle tissue. That is, the effect of this hormone is similar to going to the gym: minus fat, plus muscles.

Among the various tips on how to activate brown fat, the proposal to use Viagra looks original. The fact that this legendary drug also helps against obesity was reported by researchers from the University of Bonn (Germany), who published an article last year in The Journal of the Federation of American Societies for Experimental Biology. Viagra, or sildenafil, increased the amount of brown fat in mice, and also suppressed inflammatory processes in white adipose tissue.

Well, can a person himself help increase the proportion of brown fat in the body, without waiting for medications to appear? There is such a way, and it is sports and physical education. We have already mentioned above about the meteorin-like hormone, released from the muscles when physical stress. Also, muscle loads increase the synthesis in muscles of the transcription factor PGC-1α, which turns on genes in white fat cells that convert them into brown adipocytes. (The protein factor PGC-1α works in a signaling chain associated with the TRPV4 protein, which has been used to “link” brown fat with diabetes.)

If you don’t want to spend time on physical exercise, your friends will help you lose weight. In 2011, researchers from Ohio University (USA) found that increased social activity helps fat mice lose weight, and protects thin ones from obesity, even if fed fatty foods. Communication with other mice increased the proportion of brown fat in the animals’ bodies, and the connecting molecular link was a fairly well-known protein called “brain-derived neurotrophic factor” (BDNF), the level of which increased in nerve cells during an intense social life.

Finally, another way to activate brown fat, which naturally suggests itself, is cold. Indeed, if the activity of brown fat cells is increased by cold, then why not freeze for therapeutic purposes for those who are overweight? Employees of the University of Maastricht (Netherlands) tried to evaluate the effectiveness of this method. For 10 days, they forced volunteers to sit for six hours every day in a room with an air temperature of 15 o C. The brown fat of the experiment participants was actually activated, they stopped freezing, and their energy expenditure increased by 30%. However, it is still unclear whether such activation is enough for truly significant weight loss.

But if brown fat alone is not enough, white fat will help - it, as it turns out, can also break down fat with the release of heat if it gets cold around. Researchers from Harvard (USA) found that white adipocytes themselves, without intervention nervous system and independent of brown fat, can sense cold and participate in thermoregulation.

To be fair, there is some evidence associated with brown fat that may dampen enthusiasm for it. For example, oddly enough, in some experiments it increased the risk of atherosclerosis, provoking an increase in the proportion of “bad” fats - low-density lipoproteins - in the blood. However, these results still need to be confirmed in clinical studies.

It is possible that the diversity of lipid tissues is not limited to white and brown fat. Two years ago, employees of the Dana-Farber Cancer Institute (USA) discovered that there is also beige fat in the human body. Its cells are similar to brown fat cells and also burn excess lipids to produce heat, but differ in some significant biochemical and genetic characteristics. It is possible that those adipocytes that are considered brown in humans are actually beige. However, even if adult brown fat is indeed fake, researchers just need to switch to beige fat,” which can also be used to regulate metabolism and prevent obesity.

Surely few people know that there are several types of adipose tissue - white, brown and beige, the cells of which function differently.

The bulk of fat in our body is white adipose tissue, which is essentially a storehouse of excess calories.

Brown fat cells, on the other hand, burn calories.

Activated brown adipose tissue can produce 300 times more heat than any other tissue in the body. In a 30-minute workout, 57 grams of brown fat burns the same amount of calories.

If almost all adults have brown fat in their bodies, why not put it to work for you?

Below are tips that will help you increase their activity, which will ultimately lead to rapid weight loss.

1. Lowering the temperature activates the work of brown fats

Swedish scientists have conducted interesting experiments. They studied changes in the body of five subjects who spent two hours in a room with an air temperature of 17 °C to 19 °C. In another experiment, subjects lowered their body temperature even further: they alternately dipped one leg into ice water for 5 minutes, then pulled it out of the water for 5 minutes, etc.

The research results showed that in all subjects, when the air temperature dropped, the volume of brown adipose tissue increased, and additional exposure to cold water led to an increase in the activity of these fat cells by 15 times.

2. Cooling the skin causes brown fat cells to become active.

A decrease in temperature sends a signal to the brain, which instructs it to stimulate the activity of brown adipose tissue. This can happen in two ways different ways: either using nerve impulses, which will stimulate the activity of brown fat cells; or impact on vascular system, which leads to increased blood flow to adipose tissue.

So why should we be cold all the time now? Not at all! Studies have shown that spending two hours in a room at a temperature of 15 °C in summer clothes is enough to not only activate the activity of brown fat cells, but also burn an additional 100 to 250 calories, depending on the person’s age.

Decline temperature regime Setting the thermostat in your home or office to an average of 16 °C will increase the activity of brown fats, which will ultimately lead to significant loss weight.

3. One apple a day, including the peel, helps you maintain normal weight.

IN apple peel contains a large amount of ursolic acid - a substance that promotes the increase of brown adipose tissue and muscle mass. In addition, it helps solve problems with obesity and glucose intolerance.

Eat at least one apple a day, peeled, or include foods such as blueberries, plums, cranberries, and prunes - all of which contain ursolic acid.

This useful substance It is also included in many herbs: thyme, basil, lavender, oregano, buttercup, peppermint, hawthorn and periwinkle.

4. Include low-fat, high-carb foods in your diet.

There is no conclusive evidence yet as to which foods or nutrients contribute to active work brown fat cells.

When examining cancer patients, radiologists try to reduce the activity of brown fats, since the thermal energy that is generated during their life can mask tumors. Therefore, doctors advise patients to eat foods that are high in fat and low in carbohydrates before the examination.

From this we can conclude that foods containing low fat and high carbohydrates will help you lose weight due to the activity of brown fat cells.

5. Training in temperatures below 18°C

You can also speed up your weight loss by exercising in temperatures below 18°C. This will burn a lot more calories.

During exercise, faster evaporation of sweat from the surface of the skin will produce a cooling effect that will lead to the activation of brown fat cells.

The higher the air temperature where you train, the lower their activity. When too high temperatures their activities may be suspended.

6. Activate the formation of melatonin in the body

It turns out that there is not only white and brown fat, but also beige fat, which is also capable of burning calories, but to a lesser extent. However, it also has another useful function - it increases the production of melatonin. This hormone plays a very important role in normalizing the sleep-wake cycle.

Regular, healthy sleep benefits the body in all ways, including increasing the ability of beige fats to burn calories.

You can increase melatonin levels in your body naturally: getting more sunlight during the day (to replenish vitamin D reserves); avoiding active rays of the blue region of the visible spectrum before bedtime; eating foods rich in melatonin - tomatoes, cherries, almonds.

7. Eat regularly and correctly - no overeating or fasting

To activate brown fats and increase their levels in the body, you need to ensure that the brain neurons responsible for the feeling of hunger are working efficiently.

Reducing your calorie intake will not help turn white fat into brown fat, so fasting is useless!

With an excess of calories, white fat reserves increase, in addition, this reduces the ability of brown fat to burn calories.

All these findings were confirmed by research from Harvard University.

8. Monitor your sugar levels and diet

Brown fats are considered beneficial for diabetics as they can increase the metabolism of blood sugars.

In the body of people with low level glucose is usually contained more in this adipose tissue.

Scientists have discovered a special protein in brown fat that can speed up the metabolism of white fats. Experimental mice deprived of this protein began to expend less energy, gained weight and developed diabetes.

Do what these smart mice did - speed up your weight loss by activating brown fats! How, you ask?

One way is to avoid sudden increases or decreases in sugar levels. At critical moments, the brain automatically begins to slow down metabolic processes, making it more difficult to lose weight.

Brown fat cells can act as a trigger for increased metabolic activity. This helps to effectively combat the metabolic decline that occurs during dieting.

As people age, they tend to gain 10 kg of extra weight for every 10 years of their life. Burning calories will help you activate metabolic processes in organism.

By burning 200 to 300 calories a day, you will eliminate 0.5 kg of fat that could accumulate in a couple of weeks.

Ready to turn on yours body fat to work?

Brown fat– adipose tissue present in the body of mammals along with white fat. Thermoregulation function – converts calories into heat. Contains many capillaries, since the need for oxygen saturation is higher than that of the fat layer white. The brown (brown) color comes from iron located in the mitochondria. Brown fat is natural fat burner, as it converts white fat lipids into energy.

In a newborn's body, brown fat makes up 5%. Due to their small body size, infants spend heat intensively; the body does not regulate temperature sufficiently (children do not know how to shiver when they feel cold). Hypothermia is dealt with by islands of brown fat, which are concentrated around the neck, on the back and shoulders.

As you get older, this type of fat decreases, making it more difficult to lose weight. Therefore, problems with excess weight occur in middle-aged and older people more often than in young people. The amount of brown fat is affected genetic predisposition, gender(men have less than women), glucose balance and insulin sensitivity (the lower the sugar level, the thicker the “useful” adipose tissue), taking beta blockers, content, irisin production due physical activity(increase).

Video: Muscle vs fat

How to increase the amount of brown fat in the body

Thermo diet - losing weight with cold

A decrease in body temperature causes brown fat to become more active, replacing white fat more intensively and producing heat to restore balance. This property is used to build subcutaneous brown fat, which helps fight excess weight. Metabolism accelerates due to cold, excess reserves are burned.

• Pouring or bathing with cool water.
• Drink with a few ice cubes.
• Reducing layers of clothing - replacing a sweater with a scarf and so on.
• Keeping the room cool (16 degrees) during night sleep.
• Air baths.

Perform procedures to cool the body gradually, otherwise you will catch a cold instead of losing weight. Receptors that inform the brain about a decrease in ambient temperature function on the surface of the skin. Hypothermia of the core of the body is dangerous.

Normalization of sleep and melatonin

Melatonin– a hormone responsible for regulating circadian rhythms. Slows down aging, affects immunity, endocrine processes, digestion, blood pressure. An increase in this substance in the body has a beneficial effect on the formation of brown fat deposits. The deficiency of the hormone is compensated by dietary supplements. Obesity (interesting fact, those with obesity of 2nd degree or higher are not accepted into the army) is a direct consequence of insufficient melatonin production. A natural way to cope with a lack of melatonin is to normalize your sleep. . This will help you lose weight and cope with other problems that insomnia leads to. The importance of melatonin in the fight against excess weight is important for people over forty, since the amount of fat Brown decreases and needs to be replenished.
Measures for natural recovery sleep

• At least an hour before bedtime, turn off the TV and computer. Radiation forces the body to work in daytime mode and slows down the formation of melatonin.
• Bright light during the day and pitch darkness at night.
• Remove devices that emit electromagnetic waves from the bedroom.
• Temperature for comfortable sleep– 21 degrees maximum.

Physical exercise

Irisin converts white fat deposits into brown ones. This is a hormone released during physical exercise and preventing obesity. During sports or other strength activities, energy is consumed more intensely than necessary to achieve results.

Directions in the fight against obesity using brown fat

1. Fight obesity with irisin injections into the blood. Overweight mice were injected with this hormone, the layer of white fat was intensively converted into brown without changes in diet or exercise, and blood sugar levels decreased.
2. Transplantation of brown fat from the back of mice into abdominal cavity(in the liver area) to other animals of this species. White fat deposits have decreased and glucose levels have returned to normal. Brown fat cells burned lipids.

Attempts to create a miracle drug for people based on irisin have not yet yielded tangible results. Human brown fat has a different composition than mouse fat; under the influence of the hormone, individual cells of “harmful” fat are replaced with “good” ones. Forced acceleration of metabolism is a gross interference in the functioning of the body, side effects cover up the benefit. Irisin injections and brown fat transplantation as ways to combat obesity are the topic of further research and experimentation.

Brown fat - natural helper in the fight against obesity. Increase and activation of this species subcutaneous tissue using a thermo-diet, physical exercise, and normalizing sleep are natural ways to keep your weight normal. Proper nutrition and healthy image life will strengthen and consolidate the results.