Written by Slawomir (“Swavak”) Gromadzki, MPH

Leptin is another precious hormone which is secreted by fat cells and regarded as the most powerful among hormones capable of controlling our appetite. Apart from that, it improves metabolism and increases the amount of fat released from fat tissue.

Leptin is also the signalling hormone in the body between fat cells and brain cells. Your brain will stop craving food only when it senses an adequate amount of Leptin. Normally, when everything functions properly, leptin should go to your brain cells, touch their special receptors, and stimulate them to tell you, “Ok, you’ve got enough! Do not to eat any more!”

According to some new studies leptin also makes our immune system happy which is the best way to prevent this system from turning against us and developing dangerous autoimmune diseases. When our immune system is not relaxed and happy, due to leptin resistance, unhealthy lifestyle, and too much stress, it may turn against us attacking and destroying various organs or parts of our body.

Key symptoms of leptin deficiency or resistance include: weight gain, late night eating, stress eating, uncontrollable sugary and junk food cravings. If the problem of leptin resistance is left unhandled it leads to obesity, diabetes, heart disease, cancer, fibromyalgia, high blood pressure, and other health-related problems. Apart from that, new studies demonstrated that leptin resistance also elevates the bad LDL cholesterol levels.

The key factors which contribute to the development of leptin resistance are the following: stress and high levels of stress hormone cortisol, sedentary lifestyle (lack of physical activity), insulin resistance, diet high in refined sugar, food allergies, diet rich in animal fat leading to high level of triglycerides in the blood, inflammation, environmental toxins, and liver insufficiency.

Studies investigating the relationship between zinc and leptin show that zinc may critically impact leptin secretion. Zinc supplementation to the obese mice increases leptin levels and restoration of obesity induced by sucrose. It means that both leptin resistance and low levels of this very important hormone and appetite suppressor, which occurs in obesity, might have resulted from zinc deficiency. The relationship between zinc and leptin was examined also in humans who had zinc deficiency caused by refined diet. Zinc supplementation to these individuals resulted in significant increase in leptin secretion.

Fortunately, it is still possible to reverse leptin resistance by bringing your organism back to its natural state of health and wellness. And the only way you can achieve this goal is again through regular exercise, stress control, and loaded with fibre plant-based diet. All these three factors will remove any inflammations and hormonal imbalances, improve metabolism, lower cholesterol and triglycerides levels, detoxify your body and liver, and will lead to many other beneficial changes eventually resulting also in weight loss.

In order to boost leptin you have to eat more fibre in the form of unrefined grains, fresh and dried fruits, vegetables, legumes, seeds, and nuts. Fiber from these products will expand in your stomach by absorbing water and thus it will make you feel full and willing to consume less food. As soon as your appetite is satisfied, more leptin is produced.

Try to go to bad earlier and sleep more (7-8 hours each night) as researchers demonstrated that whenever people don’t get enough sleep and rest, their organism produce less leptin and as a result they feel hungry and had tendencies to overeat.

To boost leptin consume plant foods high in omega-3 fatty acids such as seeds and nuts, but especially soaked chia seeds and ground flax seeds (linseeds). People who are overweight or obese release too much of certain kind of molecules which are used by our organism to fight inflammation. Unfortunately, these molecules tend to reduce leptin’s ability to communicate with the brain, and this in turn is regarded as one of the key causes of leptin resistance. Omega-3 fatty acid, however, by its ability to control inflammation is able to reduce the production of these molecules.

In the beginning when researchers noticed that mice deprived of leptin became obese and after leptin injections recovered from obesity, they thought that leptin supplementation would become an effective treatment for obesity in humans. But, does it mean that obese or overweight people should take leptin injections or pills? It probably wouldn’t be a good solution because experiments revealed that leptin injections may increase aggressiveness. Leptin pills wouldn’t even work because leptin is a type of protein and it would be digested in your stomach. Thus, all those supplements of leptin which are widely advertised now don’t contain leptin but only some ingredients which are supposed to help this hormone to increase our feeling of satiety. And, to be honest, nobody really knows whether this supplements are effective. Apart from that, when later scientists discovered that obese people produce enough leptin (much more than thin people) they realized that it wasn’t leptin deficiency but leptin resistance that led to obesity. It means that even if obese people receive leptin injections it will not significantly reduce their appetite and metabolism simply because in their case leptin is not able to do its job properly as their brain cells have no functional leptin receptor. Leptin tries to phone brain cells and tell them to reduce appetite but brain cells do not pick up the phone simply because their phone is damaged and as a result they can’t hear anything.

Leptin resistance is caused by the typical modern sedentary, stressful and unhealthy lifestyle which also includes the bad and high in fat, sugar, and refined products diet. The good news, however, is that although leptin resistance (and also insulin resistance) which leads to gaining weight, easily develops in rats (when they are given unlimited access to high in sugar and fat foods), yet the same harmful process is always reversed as soon as these rats are back on healthy diet.

We know that one of the leptin’s functions is to influence certain brain receptors which are responsible for reducing our food consumption. Researchers showed that diet high in refined sugar (especially fructose) leads to leptin resistance in rats. Rats on a normal unrefined (rich in fiber) plant-based diet do not develop leptin resistance and for this reason leptin can easily bind to brain cells’ receptors thus leading to reduced appetite. But rats fed with refined sugar (and also any refined carbohydrates such as white flour products which turn in the body into sugar) even after receiving leptin injections, do not reduce their food intake (and appetite), because the brain cells’ receptors cease to react to leptin properly. And, when later an animal fat was added to the rats’ diet they quickly became overweight.

When you consume foods which contain refined sugar, then as a result the sugar level in your blood gets high quickly, which causes pancreas to produce insulin to reduce the sugar level. Unfortunately, when insulin levels in your organism are high (because blood sugar level is higher than normal), it leads to leptin deficiency, and eventually brain is unable to hear leptin’s desperate cry “stop eating!” Therefore, in order to break this vicious circle you have to stop consuming foods rich in refined sugar and instead start eating high-fibre plant-based foods. As a result your brain cells and fat cells will be able to effectively communicate again, reducing your appetite, and improving your metabolism, which will consequently result in a natural and permanent fat loss.

As far as obesity is concerned, leptin is an incredibly important hormone because it regulates our metabolism, appetite, and how much fat we are going to store and burn. When leptin works properly, it keeps our body weight balanced regardless of the amount of food we consume. It does this by stimulating liver to improve fat burning and forcing thyroid hormones to speed up metabolism. So, normally, as soon as we gain weight, our fat cells should release leptin to suppress our appetite and increase metabolism and burn fat more efficiently so that we could lose weight. By the way, isn’t it incredible how wonderfully our body is created and works?! It amazes me when I realize that our own fat can behave in such a clever and intelligent way! It is so mind boggling because it seems that our own fat demonstrates shocking ability to regulate itself by releasing hormone which sends orders to the brain cells demanding from them to suppress appetite and increase metabolism to reduce the amount of fat in the fat cells! This efficiently working mechanism, which boosts metabolism, is probably one of the reasons why some individuals are still slim and even skinny in spite of the fact that they eat a lot.

Experts suggest that instead of taking leptin supplements which haven’t been proven to help, obese and overweight people should rather aim at coping with leptin resistance by reducing resistance to insulin, and also lowering blood triglyceride levels. It is important to cope with insulin resistance because it generates leptin resistance. And you can easily recover from insulin resistance by low sugar and low fat diet, exercise and stress control.

But why obese people need to lower blood triglycerides levels? It is necessary because if you have too much triglycerides in your body they do not allow leptin to communicate with your brain to prevent you from overeating. It is also important to know that insulin-resistance greatly contributes to accumulation of triglycerides in your body. That’s why you need to cope with both insulin-resistance and high blood triglycerides level. In this way you will enable leptin to effectively send signals to your brain cells again. Triglycerides are produced in our body from carbohydrates (sugars) or they come with animal foods (dairy and meat products) which unlike plant foods contain triglycerides. Apart from leading to cardio-vascular diseases triglycerides contribute to excessive fat storage in your body by depriving leptin of its ability to communicate with brain cells which in turn leads to gluttony and obesity. The best way therefore to reverse this process, is again by switching to a plant-based unrefined diet, simply because it is free from bad fats (triglycerides and cholesterol) and refined carbohydrates (sugar). And research has already confirmed that leptin resistance is triggered especially by eating lots of refined sugary foods and drinks.

We know that type 2 diabetes is caused by stress, unhealthy diet, and bad lifestyle, as it leads to accumulation of certain proteins called endoplasmic reticulum (ER) which are involved in the synthesis of proteins and works as cell’s membrane factory. As a result, these harmful proteins lead to the development of obesity-induced insulin resistance which is the key cause of type 2 diabetes. This fact, however, inspires us to draw a conclusion that this ER stress may in a similar way trigger the development of leptin resistance and lead to obesity in humans. Sedentary lifestyle, stress, and especially the animal-based and high in refined sugar and white flour diet probably trigger another harmful protein in the body which also causes leptin resistance and obesity. And after drawing this simple and obvious conclusion I have found that scientists already suspect certain protein called CRP of being responsible for impairing leptin signalling abilities. Stress as well as diet high in refined sugar and fat, and also protein rich meals (meat and dairy) suppress the production of leptin as it constantly creates an ER stress in the hypothalamus cells of mice thus activating a harmful protein response and leading to leptin resistance which stimulated mice to consume more food, become less active and gain weight.

Back in Poland I had a privilege to translate series of very interesting health seminars by American physician Dr. Sang Lee who proposed a very interesting and possible reason why our own organism may manufacture a harmful proteins which, for example, cause insulin resistance in type 2 diabetes. He said that our genes are very sensitive to different needs, lifestyle, and the condition of our nervous system. Thus, he suggested that when we don’t exercise our body ‘thinks’ we are already dead because only dead people do not move. When we are stressful or depressed, and especially when we don’t enjoy life and think about suicide, when we use harmful medications, coffee, alcohol and other stimulants which leads to premature death, consume dead animal foods such as meat products, then the genes in our body are constantly receiving the signals or messages of death. As a result after some time the genes somehow ‘draw a conclusion’ that either we don’t want to live or we are already dead, and those death signals stimulate them to produce a harmful proteins which eventually cause insulin resistance in type 2 diabetes, leptin resistance in obese people, or for example even the brain damage in Alzheimer’s disease (caused by an abnormal protein too). And even though this idea hasn’t been proven yet it is very interesting and sounds reasonable.

Nevertheless, if the above is true, then it means that in order to reverse the problem and remove the protein which probably makes your cells resistant to leptin you need to avoid refined sugar, give up on deadly stimulants, switch to a vegan unrefined living foods, exercise every day, control stress, enjoy life, think positive as in this way you will flood your body and genes with life signals and messages, showing your organism that you are not dead but alive! And because genes in your body are very sensitive to your needs the problem will be solved and leptin receptors will again start to properly react to leptin reducing your appetite and improving your metabolism!

The problem of leptin or insulin resistance can’t be solved by a leptin tablet or injection because enough leptin and insulin is already present in the body of obese person. The only way to recover from this problem is by removing the true cause of leptin resistance which is unhealthy diet, lack of exercise, and inability to control stress.

First of all, you need to come back to the original plant-based unrefined, unprocessed and free from additives, stimulants or preservatives diet our Creator gave human kind in the beginning: I now give you every seed-bearing plant on the face of the entire earth and every tree that has fruit with seed in it. They will be yours for food. (Genesis 1:29, NET Bible). Second, you have to exercise on a regular basis and live more physically active life. And finally, you also need to think positive, learn to enjoy life, effectively control stress, and get rid of all your existential fears. Because stress and existential fears are regarded as the key factors which contribute to the development of leptin resistance you need to study the last two chapters of this book which deal with this subject.




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