Each and every one of us is a combination of lives within lives. We are made up of trillions of individual living cells that each must maintain itself. Even more significantly, the cells must communicate and interact with each other to form a republic of cells that we call our individual self. Our health and life depends on how accurately instructions are conveyed to our cells so that they can act in harmony. It is the communication among the individual cells that will determine our health and our life. The communication takes place by hormones. Arguably therefore, the most important molecules in your body that ultimately will decide your health and life are hormones.
Many would say that genes and chromosomes are the most important molecules, however once born your genes pretty much just sit there; hormones tell them what to do. Certainly, the most important message that our cells receive is how and what to do with energy, and therefore life cannot take place without that.
The two most important hormones that deliver messages about energy and metabolism are insulin and leptin.
Metabolism can roughly be defined as the chemistry that turns food into life, and therefore insulin and leptin are critical to health and disease. Both insulin and leptin work together to control the quality of your metabolism (and, to a significant extent, the rate of metabolism).
Insulin works mostly at the individual cell level, telling the vast majority of cells whether to burn or store fat or sugar and whether to utilize that energy for maintenance and repair or reproduction. This is extremely important for on an individual cell level turning on maintenance and repair equates to increased longevity, and turning up cellular reproduction can increase your risk of cancer.
Leptin, on the other hand, controls the energy storage and utilization of the entire republic of cells allowing the body to communicate with the brain about how much energy (fat) the republic has stored, and whether it needs more, or should burn some off, and whether it is an advantageous time nutritionally-speaking for the republic –you– to reproduce or not.
Leptin is a very powerful and influential hormone produced by fat cells. Prior to leptin’s discovery, fat was viewed as strictly an ugly energy storage depot that most everyone was trying to get rid of. After it was discovered that fat produced the hormone leptin (and subsequently it was discovered that fat produced other very significant hormones), fat became an endocrine organ like the ovaries, pancreas and pituitary, influencing the rest of the body and, in particular, the brain.
Leptin, as far as science currently knows, is the most powerful regulator that tells your brain what to do about life’s two main biological goals: eating and reproduction. Your fat, by way of leptin, tells your brain whether you should be hungry, eat and make more fat, whether you should reproduce and even make babies, or (partly by controlling insulin) whether to “hunker down” and work overtime to maintain and repair yourself. In short, leptin is the way that your fat stores speak to your brain to let your brain know how much energy is available and, very importantly, what to do with it. Therefore, leptin may be “on top of the food chain” in metabolic importance and relevance to disease.
It has been known for many years that fat stores are highly regulated. It appeared that when one tried to lose weight the body would try to gain it back. This commonly results in “yo-yo” dieting and in scientific circles one talks about the “set point” of weight. It has long been theorized that there must be a hormone that determines this.
Science points now to leptin as being that hormone.
If a person is getting too fat, the extra fat produces more leptin which is supposed to tell the brain that there is too much fat stored, more should not be stored, and the excess should be burned.
Signals are therefore sent to an area of the brain in the hypothalamus (the arcuate nucleus) to stop being hungry, to stop eating, to stop storing fat and to start burning some extra fat off.
The importance of insulin in health and disease is becoming well-known. Aside from its obvious role in diabetes, it plays a very significant role in hypertension, cardiovascular disease, and cancer.
However leptin may even supersede insulin in importance, for new research is revealing that in the long run glucose and therefore insulin levels may be largely determined by leptin.
It had been previously believed that the insulin sensitivity of muscle and fat tissues were the most important factor in determining whether one would become diabetic or not. Elegant new studies are showing that the brain and liver are most important in regulating a person’s blood sugar levels especially in type 2 or insulin resistant diabetes.
People become leptin-resistant by the same general mechanism that people become insulin-resistant; by overexposure to high levels of the hormone. High blood glucose levels cause repeated surges in insulin, and this causes one’s cells to become “insulin-resistant” which leads to further high levels of insulin and diabetes. It is much the same as being in a smelly room for a period of time. Soon, you stop being able to smell it, because the signal no longer gets through. This is the same happens with leptin. It has been shown that as sugar gets metabolized in fat cells, fat releases surges in leptin, and those surges result in leptin-resistance just as it results in insulin-resistance.
The only known way to reestablish proper leptin (and insulin) signaling is to prevent those surges, and the only known way to do that is via diet and supplements. When leptin signaling is restored, your brain can finally hear the message that perhaps should have been delivered decades ago; high leptin levels can now scream to your brain that you have too much fat and that you better start burning some off for your life is in danger. Your brain will finally allow you access into your pantry that you have been storing your fat in. Your cells will be fed the food from that fat and they will be satisfied. They will not know whether that food came from your belly fat or from your mouth; nor will they care. They will be receiving energy that they need and will not have to ask for more. You will not be hungry.
This also makes counting calories irrelevant, for the calories that you put into your mouth today are not necessarily what your cells will be eating; that will be determined primarily by leptin. Whether or not you put food into your mouth, your cells will be eating, and if they cannot eat fat they must eat sugar. Since little sugar is stored, that sugar will be had by making you crave it, or by turning the protein in your muscle and bone into sugar. This contributes in a major way to weakness and osteoporosis. Whether or not this lean tissue wasting happens is determined by your capacity, or incapacity, to burn fat, and that is determined by your ability to listen to leptin.
When you become leptin-resistant, your body can no longer hear the messages telling it to stop eating and burn fat — so it remains hungry and stores more fat.
Leptin-resistance also causes an increase in visceral fat, sending you on a vicious cycle of hunger, fat storage and an increased risk of heart disease, diabetes, metabolic syndrome and more.
People become both insulin and leptin resistant by eating the typical
American diet full of sugar,refined grains,processed foods and not a whole lot else. The solution is to instead eat a diet that emphasizes good fats and avoids blood sugar spikes — in short a dietary program detailed which emphasizes healthy fats, lean meats and vegetables, and restricts sugar and grains.
Ref: Ron Rosedale, M.D.