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Why Do Insulin Receptors Stop Working

Insulin Resistance

Insulin Resistance

Insulin resistance (IR) is a pathological condition in which cells fail to respond normally to the hormone insulin. The body produces insulin when glucose starts to be released into the bloodstream from the digestion of carbohydrates in the diet. Normally this insulin response triggers glucose being taken into body cells, to be used for energy, and inhibits the body from using fat for energy. The concentration of glucose in the blood decreases as a result, staying within the normal range even when a large amount of carbohydrates is consumed. When the body produces insulin under conditions of insulin resistance, the cells are resistant to the insulin and are unable to use it as effectively, leading to high blood sugar. Beta cells in the pancreas subsequently increase their production of insulin, further contributing to a high blood insulin level. This often remains undetected and can contribute to the development of type 2 diabetes or latent autoimmune diabetes of adults.[1] Although this type of chronic insulin resistance is harmful, during acute illness it is actually a well-evolved protective mechanism. Recent investigations have revealed that insulin resistance helps to conserve the brain's glucose supply by preventing muscles from taking up excessive glucose.[2] In theory, insulin resistance should even be strengthened under harsh metabolic conditions such as pregnancy, during which the expanding fetal brain demands more glucose. People who develop type 2 diabetes usually pass through earlier stages of insulin resistance and prediabetes, although those often go undiagnosed. Insulin resistance is a syndrome (a set of signs and symptoms) resulting from reduced insulin activity; it is also part of a larger constellation of symptoms called the metabolic syndrome. Insuli Continue reading >>

Insulin And Insulin Resistance

Insulin And Insulin Resistance

Go to: Abstract As obesity and diabetes reach epidemic proportions in the developed world, the role of insulin resistance and its consequences are gaining prominence. Understanding the role of insulin in wide-ranging physiological processes and the influences on its synthesis and secretion, alongside its actions from the molecular to the whole body level, has significant implications for much chronic disease seen in Westernised populations today. This review provides an overview of insulin, its history, structure, synthesis, secretion, actions and interactions followed by a discussion of insulin resistance and its associated clinical manifestations. Specific areas of focus include the actions of insulin and manifestations of insulin resistance in specific organs and tissues, physiological, environmental and pharmacological influences on insulin action and insulin resistance as well as clinical syndromes associated with insulin resistance. Clinical and functional measures of insulin resistance are also covered. Despite our incomplete understanding of the compl Continue reading >>

The Insulin Stopped Working? Inconceivable!

The Insulin Stopped Working? Inconceivable!

Insulin resistance in diabetic pets is a pain, Highness. Anyone who says differently is selling something. Insulin resistance, according to endocrinologist extraordinaire David Bruyette, DVM, DACVIM, is a condition in which a normal amount of insulin produces a suboptimal biological response—in other words, it fails to control hyperglycemia and its resultant clinical signs. Sometimes the cause can be simple to determine and correct, such as in cases of gingivitis or urinary tract infection; other times it can be near impossible (glucagonoma, anyone?). The key is to figure out what concurrent conditions are affecting insulin and its receptors in your patient and to treat accordingly so that insulin can be effective. Here are Bruyette’s top tips for ferreting out difficult feline and canine insulin resistance cases, with a little help from a classic movie. (Can you guess which one?) Insulin resistance: You keep using that word … There is no single insulin dose veterinarians can look to that clearly defines insulin resistance, Bruyette says. But for most uncomplicated cases of diabetes in dogs and cats, glycemia should be controlled using 1.0 U/kg or less of NPH, Lente insulin, or glargine (in cats) twice daily. Insulin resistance should be suspected if hyperglycemia is noted in the face of insulin dosages exceeding 1.5 U/kg, when insulin dosages greater than 1.5 U/kg are necessary to maintain blood glucose concentrations below 300 mg/dl, or when constant changes in insulin are required to control hyperglycemia. Serum fructosamine concentrations are commonly greater than 500 μmol/L in animals with insulin resistance and can exceed 700 μmol/L if resistance is severe. Don’t forget about stress-induced hyperglycemia in cats, Somogyi response or other problems with i Continue reading >>

Insulin Resistance

Insulin Resistance

Insulin Resistance Definition Insulin resistance is not a disease as such but rather a state or condition in which a person's body tissues have a lowered level of response to insulin, a hormone secreted by the pancreas that helps to regulate the level of glucose (sugar) in the body. As a result, the person's body produces larger quantities of insulin to maintain normal levels of glucose in the blood. There is considerable individual variation in sensitivity to insulin within the general population, with the most insulin-sensitive persons being as much as six times as sensitive to the hormone as those identified as most resistant. Some doctors use an arbitrary number, defining insulin resistance as a need for 200 or more units of insulin per day to control blood sugar levels. Various researchers have estimated that 3-16 percent of the general population in the United States and Canada is insulin-resistant; another figure that is sometimes given is 70-80 million Americans. Insulin resistance can be thought of as a set of metabolic dysfunctions associated with or contributing to a range of serious health problems. These disorders include type 2 diabetes (formerly called adult-onset or non-insulin-dependent diabetes), the metabolic syndrome (formerly known as syndrome X), obesity, and polycystic ovary syndrome. Some doctors prefer the term "insulin resistance syndrome" to "metabolic syndrome." Description To understand insulin resistance, it may be helpful for the reader to have a brief account of the way insulin works in the body. After a person eats a meal, digestive juices in the small intestine break down starch or complex sugars in the food into glucose, a simple sugar. The glucose then passes into the bloodstream. When the concentration of glucose in the blood reaches Continue reading >>

What Causes Insulin Resistance? Part I

What Causes Insulin Resistance? Part I

Insulin is an ancient hormone that influences many processes in the body. Its main role is to manage circulating concentrations of nutrients (principally glucose and fatty acids, the body's two main fuels), keeping them within a fairly narrow range*. It does this by encouraging the transport of nutrients into cells from the circulation, and discouraging the export of nutrients out of storage sites, in response to an increase in circulating nutrients (glucose or fatty acids). It therefore operates a negative feedback loop that constrains circulating nutrient concentrations. It also has many other functions that are tissue-specific. Insulin resistance is a state in which cells lose sensitivity to the effects of insulin, eventually leading to a diminished ability to control circulating nutrients (glucose and fatty acids). It is a major contributor to diabetes risk, and probably a contributor to the risk of cardiovascular disease, certain cancers and a number of other disorders. Why is it important to manage the concentration of circulating nutrients to keep them within a narrow range? The answer to that question is the crux of this post. Cellular Energy Excess There has been a tremendous amount of research into the molecular mechanisms of insulin resistance in the last few decades, and certain things have become clear about it. The first is that it appears to be a 'deliberate' process-- cells activate specific signaling pathways that down-regulate insulin responsiveness. The rationale for this becomes clear when one considers what insulin does: it drives energy into cells. Insulin resistance is how the cell says "stop sending me more energy-- I have too much already!" It is a deliberate response to mitigate the negative effects of cellular energy excess. Why would a cell w Continue reading >>

Insulin Receptors

Insulin Receptors

Insulin receptors are special proteins in your cells that allow you to utilize insulin. Unfortunately if have chronically high insulin levels, your insulin receptors will stop working. This is known as insulin resistance. Insulin resistance is a very common metabolic disorder resulting from having chronically high insulin levels. If you were to consume too many carbohydrates (starches, sugars and starchy vegetables) over an extended period of time, your pancreas (the organ that secretes insulin) will have to work overtime to try to process these carbohydrates. If you have high insulin levels for too long, eventually your insulin receptors will stop working and you will develop insulin resistance (resistance to your own insulin). This condition is also commonly referred to as “pre-diabetes”. Other names for insulin resistance are metabolic syndrome, dysinsulinism and hyperinsulinism. Regardless of what you call this unhealthy state, if you have chronically high insulin levels you will be at great risk for developing diabetes, obesity, high blood pressure, heart disease, strokes, cancer, depression, thyroid disease and a bunch of other adverse health conditions. Many people, including many doctors erroneously believe that if your blood sugar levels are under control than you are doing the best you can to reduce your chances of developing complications from type 2 diabetes. The best and most important treatment for insulin resistance and to keep your insulin receptors functioning properly is to fix the cause of this problem, reducing your intake of sugars, starches and other carbohydrates. Any other treatment (like drugs, vitamins, herbs, amino acids and minerals) will only serve to cover up your symptoms and will eventually fail to help you. If you are looking to keep Continue reading >>

Blood Sugar Basics And Glucose Balance

Blood Sugar Basics And Glucose Balance

You’ve heard the terms “blood sugar” and “blood glucose” but if you’re confused about why they matter, this guide can help. What is blood glucose? Blood glucose, also known as blood sugar, is one of the most important sources of energy for your body. When you eat, food is broken down into basic nutrients: fats, proteins, and carbohydrates. Carbohydrates — fiber, starch, and sugar — are broken down into glucose or “blood sugar.” Glucose is the only fuel used by brain cells except under extreme conditions like starvation. Muscle cells use glucose during short bursts of activity like running to your car in a rainstorm. Having good blood sugar balance is an important benchmark of overall wellness because it prevents certain endocrine imbalances that can threaten your health. Glucose needs insulin to fuel your cells Glucose circulating in your blood needs help to get into the cells. Insulin, a hormone made by the pancreas, is the “key” that turns the “lock” (a cell’s insulin receptor) to let glucose enter. When a cell is working hard — like a muscle cell rapidly expanding and contracting during exercise — it needs more glucose for fuel. So the cell “summons” insulin to bring in more glucose by increasing the number of insulin receptors on its surface. Then insulin can increase the amount of glucose it has to offer the cell as necessary. Healthy glucose levels are a balancing act Blood glucose rises and falls in a process called glucose homeostasis. Blood glucose goes up after you eat carbohydrates but it can also increase in response to stress, illness, or even excitement. Rising blood glucose signals the pancreas to release more insulin so blood glucose levels stay in the healthy range. For people without diabetes, that’s around 70 ng Continue reading >>

Insulin And Insulin Resistance

Insulin And Insulin Resistance

Insulin Insulin is a hormone released from the pancreas, one of the body's endocrine organs. The body is truly fascinating the way it works because there is a neural network in the pancreas and digestive tract that coordinate insulin release. Insulin helps to regulate blood sugar and gets activated predominantly when we eat sugar and carbohydrates. But although sugar and carbs are the biggest influence of this stimulation, fats, proteins, and other hormones can influence insulin release as well. In our body, glycemic control (aka blood sugar level) is kept within a tight range. This is very important to the function of our body and so is insulin, insufficient or excess insulin secretion is life threatening. We see this in type 1 diabetes where the person must have insulin injections in order to survive. And in type 2 diabetes we see the effects of high blood sugar and insulin resulting in cardiovascular issues, oxidative stress, eye, kidney, and peripheral nerve problems. Insulin action is required throughout the body as the central nervous system uses it’s signals to control energy metabolism and balance, for reproduction, for brain function, and other functions too. But it's main role is as our energy storage hormone. Any excess calories, sugar, or carbs increases fat accumulation, which is basically insulin pushing the excess energy into storage for later use. To us that simply means an increasing waist line! Dr Robert Lustig says that around 75-80% of obesity and weight gain is high insulin shunting excess calories, predominantly from sugar and carbs, to fat! 4 Things That Drive Up Insulin 1. Insulin rises in response to a meal, especially one filled with refined sugar and carbohydrates. 2. Because of specific foods you eat…you can develop a fatty liver and deve Continue reading >>

Insulin In Central Nervous System: More Than Just A Peripheral Hormone

Insulin In Central Nervous System: More Than Just A Peripheral Hormone

Journal of Aging Research Volume 2012 (2012), Article ID 384017, 21 pages 1CNC, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal 2Institute of Physiology, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal 3Institute of Biochemistry, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal Academic Editor: Barbara Shukitt-Hale Copyright © 2012 Ana I. Continue reading >>

How Does Fat Affect Insulin Resistance And Diabetes?

How Does Fat Affect Insulin Resistance And Diabetes?

According to the Centers for Disease Control, 29 million people in America have diabetes and 86 million have prediabetes. Insulin resistance is recognized as a predictor of type 2 diabetes, heart disease, and obesity. But what causes insulin resistance? In this NutritionFacts.org video, Dr. Michael Greger talks about how fat affects insulin resistance, and about how the most effective way to reduce insulin sensitivity is to reduce fat intake. We’ve also provided a summary of Dr. Greger’s main points below. Insulin Resistance of People on High-Fat Diets vs. High-Carb Diets In studies performed as early as the 1930s, scientists have noted a connection between diet and insulin intolerance. In one study, healthy young men were split into two groups. Half of the participants were put on a fat-rich diet, and the other half were put on a carb-rich diet. The high-fat group ate olive oil, butter, mayonnaise, and cream. The high-carb group ate pastries, sugar, candy, bread, baked potatoes, syrup, rice, and oatmeal. Within two days, tests showed that the glucose intolerance had skyrocketed in the group eating the high-fat diet. This group had twice the blood sugar levels than the high-carb group. The test results showed that the higher the fat content of the diet, the higher the blood sugar levels would be. What Is Insulin Resistance? It turns out that as the amount of fat in the diet goes up, so does one’s blood sugar spikes. Athletes frequently carb-load before a race because they’re trying to build up fuel in their muscles. We break down starch into glucose in our digestive tract; it circulates as blood glucose (blood sugar); and it is then used by our muscle cells as fuel. Blood sugar, though, is like a vampire. It needs an invitation to enter our cells. And that invit Continue reading >>

Pcos, Inflammation & Insulin

Pcos, Inflammation & Insulin

What do PCOS, inflammation & insulin have in common? Like many chronic conditions and disease, inflammation and insulin dysregulation are at the root of the issue, with PCOS being no exception. In fact, inflammation and insulin resistance can lead to infertility, difficult and painful periods, PCOS, high testosterone, mood disorders, and many other common hormonal symptoms women struggle with. Can You Prevent PCOS by Decreasing Inflammation & Regulating Insulin? Many of us are aware that blood sugar imbalances and issues with insulin can lead to diabetes, heart disease, and cancer. But not many people (docs included) recognize that these play a crucial role in balancing hormones too. What if you eat right and exercise? While diet and exercise are absolutely foundational to health blood sugar levels and excellent hormones, it will only take you so far if you’re inflamed. Inflammation alone can lead to insulin resistance and high blood sugar. Yup, you can eat right and exercise and still develop diabetes if you’re inflamed. There is now evidence to suggest insulin resistance that is a result of inflammation may actually cause PCOS rather than being a result of the disease. This is cascade called lipotoxicity — a condition in which dysfunctional fat cells secrete inflammatory chemicals that ultimately causes insulin resistance. How does inflammation cause insulin resistance & PCOS? Inflammation causes blood sugar dysregulation, which is why in my clinic we go searching for hidden cause of inflammation like adrenal issues and hidden infections.. Inflammation makes your cells rigid, making it harder for insulin to get sugar into the cell. This causes you body to make more insulin. When the cells are bombarded with sugar they eventually become insulin resistance. Basica Continue reading >>

Understanding Insulin Resistance

Understanding Insulin Resistance

It's a precursor to diabetes, but it also can be reversed Though you may not be living with diabetes, your body could be battling against the hormone insulin. The condition, called insulin resistance, occurs when insulin can't effectively do its job. "People often don't realize that insulin resistance can develop into diabetes," said Dawn Sherr, a diabetes educator for the American Association of Diabetes Educators. "And if they're not aware they're insulin resistant, they don't know what steps they can take to prevent it." Insulin resistance is a fuzzy, often misunderstood concept. Here, we answer five common questions. Q: How does the body become resistant to insulin? A: When you eat, food is broken down into glucose to be used for energy. Insulin, a hormone produced in the pancreas, tempers the amount of sugar in the bloodstream by helping glucose get into the muscle, fat and/or liver cells. "We think of insulin as a 'key' that opens doors to the body's cells, so glucose can enter," said diabetes educator Gary Scheiner. With insulin resistance, it's like having locks that are frozen or rusty. The keys won't turn, and glucose can't get into the cell. The pancreas, alarmed by the increase in blood sugar, cranks out more insulin. Eventually, the overworked pancreas breaks down. Blood sugar levels rise even further, causing pre-diabetes and setting the stage for Type 2 diabetes. "Most people think of diabetes as high blood sugar caused by too little insulin," said Scheiner, the author of "Think Like a Pancreas. "But the insulin resistance is really the root cause of almost all cases of Type 2 diabetes. Q: What is pre-diabetes? A: The body's cells are insulin resistant; the levels of glucose in the blood are higher than normal, and the pancreas can't make enough insulin t Continue reading >>

Too Much Insulin? How To Reset Your Metabolism

Too Much Insulin? How To Reset Your Metabolism

By: Mark Hyman, M.D. Are your hormones out of balance? Does your life feel like a song played badly out of tune? If so, the problem may have to do with imbalances in your hormones, which are wreaking havoc on your body and mind. Today I want to focus on the most common — and therefore the most problematic — of hormonal problems in Americans today: too much insulin. When you eat too much sugar, flour and white rice, your insulin levels spike. When this happens, your cells become resistant to its effects. So you pump out more and more insulin, become even more resistant to its effects, and end up in the vicious cycle of insulin resistance. Insulin resistance can cause energy and mood swings — and it can take you down the slippery road toward high blood pressure, heart disease, obesity, cancer, brain aging, dementia, and more. Between 80 and 100 million Americans suffer from insulin resistance. It is not exactly the same in everyone, but the ultimate consequences can be similar. How do you know if you suffer from insulin resistance? Most people with insulin resistance have extra fat around the middle. (Quick Tip: Check your waist-to-hip ratio — the measurement around your belly button divided by the measurement around your hips. If it is greater than 0.8, you likely have insulin resistance.) You may be tall, thin, short, fat, or any combination of these and still have insulin resistance. The only way to know for sure is to take an insulin response test, which measures blood sugar and insulin while you are fasting and one and two hours after you consume a 75-gram sugar drink. Just measuring blood sugar alone isn’t enough. You have to measure insulin — this is something that many doctors miss. Fortunately, balancing blood sugar and correcting insulin resistance a Continue reading >>

Glucose Insulin And Diabetes

Glucose Insulin And Diabetes

Every cell in the human body needs energy to survive and do its different functions. If we're talking about a brain cell, it needs energy to keep stimulating other brain cells and sending on signals and messages. If it's a muscle cell, it needs energy to contract. They need energy just to do the basic functions of a cell. And the place that they get that energy from, or the primary source of that energy, is from glucose. Glucose is a simple sugar. If you were to actually taste glucose, it would taste sweet. And glucose gets delivered to cells through the bloodstream. So this right here, I'm drawing some blood that's passing by a cell. Maybe the blood is going in that direction over there. And inside the blood, let me draw some small glucose molecules passing by. And so in an ideal situation, when a cell needs energy, glucose will enter the cell. Unfortunately, it's not that simple for the great majority of cells in the human body. The glucose won't enter by itself. It needs the assistance of a hormone or a molecule called insulin. So let me label all of these. This right here is the glucose, and it needs insulin. So let me draw insulin as these magenta molecules right over here. That over there, that is insulin. And the surface of the cells, they have insulin receptors on them. And I'm just drawing very simplified versions of them, kind of a place where these magenta circles can attach, can bind. And what happens is, in order for the glucose to be taken up by the cell, insulin has to attach to these receptors, which unlocks the channels for glucose. In order for the glucose to go in, insulin has to bind to the insulin receptors. And then, once that happens, then the glucose can be taken up by the cell. Now, unfortunately, things don't always work as planned. So let me d Continue reading >>

Does Fat Cause Insulin Resistance?

Does Fat Cause Insulin Resistance?

For decades now, we have been told that fatness (or “obesity”) is a major cause of diabetes. Health “experts” have warned about this, but they could never say how being overweight could cause insulin resistance (IR). Without IR, you can’t have Type 2 diabetes, so the whole “blame fat” theory has been suspect. Well, now they have a plausible explanation. Obesity may cause inflammation, causing IR, leading to diabetes. But is this theory true? Does adipose (fat) tissue really create inflammation? Or do both obesity and inflammation come from some other cause? Get ready for some science as I try to explore these questions. In a new report in the Journal of Leukocyte Biology, two Japanese scientists report that “obesity is associated with a state of chronic, low-grade inflammation.” They explain that as fat cells get larger, they seem to attract immune cells called macrophages. These cells produce inflammatory chemicals called cytokines that help cause insulin resistance. Chief among these chemicals are interleukin-6 and tumor necrosis factor-alpha. In animal models, insulin resistance doesn’t occur until after macrophages invade the fat cells. So the question remains, which comes first, the inflammation or the fatness? What draws the immune cells into adipose tissue? Remember that most overweight people never develop diabetes. And some overweight people have much more inflammation than others. (The same is true of thin people, of course.) Why do some develop this fat-related inflammation and some don’t? Some think that weight itself provokes inflammation. According to French scientists writing in the journal European Cytokine Network, weight loss is associated with reduced “macrophage infiltration” and reduced inflammation. Also, another chemical, Continue reading >>

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