Fat Vs Sugar In The War On Insulin Resistance
Fat vs Sugar in the war on insulin resistance Insulin resistance and the incidence of type 2 diabetes are on the rise. Dietary choices are implicated in increasing risk, but sometimes it is hard to know where to look when seeking advice on what to eat! But is it fat or sugar we should be more concerned about? Or both?It seems the answer to that question is a little complex. First, lets look at the action of insulin. Insulin impacts the synthesis and storage of glucose, fat and amino acids. It is primarily recognised for its regulation of blood glucose levels, and maintains balance of levels of sugar in the blood by: moving glucose from the blood into muscle cells or adipose (fat) tissue, and; inhibiting the formation of glucose from non-carbs, i.e. fats and proteins (a process called gluconeogenesis that takes place in the liver when blood glucose runs low).1 It then gathers excess glucose in the blood and stores it as fat. It also acts as an appetite regulator, and whilst its role is not well defined, once insulin acts to deposits fat into fat cells, leptin the hunger suppressant hormone is stimulated to release.1 In insulin resistance, it has been observed that glucose and free fatty acids are persistently high in the blood, likely due to resistant cells not heeding to insulins call, meaning less glucose uptake by muscle cells, and adipose cells no longer inhibiting free fatty acid release.1 This then results in higher levels of insulin being produced, and chronically high insulin is known as hyperinsulinemia. Liver and kidney cells do not become resistant to insulin-like the muscle and fat cells, and instead are hyper-stimulated to produce triglycerides and retain sodium respectively. This results in high levels of TGL in the blood, and high blood pressure.1Neither Continue reading >>
High Amounts Of Fat May Improve Insulin Sensitivity – New Study
Studies show that calorie-reduced diets improve insulin sensitivity, regardless of their fat content. However, it’s unclear if this is due to the composition of the diet or weight loss. For this reason, a group of scientists compared the effects of high- and low-fat diets, while maintaining stable weight. Below is a review of their findings, published in the European Journal of Nutrition. BACKGROUND Insulin sensitivity refers to how sensitive the body is to the effects of insulin. Low insulin sensitivity, also known as insulin resistance, means the body doesn’t respond to insulin efficiently. This adverse condition characterizes type 2 diabetes and can lead to abnormally high blood sugar after meals. It’s unclear exactly what causes insulin resistance, but several studies have examined how diet composition affects insulin sensitivity. Two short-term studies compared the effects of diets high in fat (50–55% of calories) and low in fat (20–25% of calories) on insulin sensitivity. They found no significant differences in insulin sensitivity between diets. Another study in older individuals showed that a 4-week, high-fat diet (42% of calories), high in saturated fat (24% of calories), did not cause significant changes in insulin sensitivity. What’s more, an 11-day study found that a very-high-fat diet (83% of calories) had no effects on insulin sensitivity, compared to a diet that contained no fat. However, the evidence is not entirely conclusive. Some studies indicate that low-fat diets may improve insulin sensitivity. In short, it seems that eating high amounts of fat does not increase your risk of becoming insulin resistant, but more research is needed. ARTICLE REVIEWED Researchers from the University of Washington in the US compared the effects of a very hig Continue reading >>
A Practical Guide To Carb Tolerance And Insulin Sensitivity
One of the biggest reasons why people go Paleo is the metabolic benefits. Most people find Paleo to be very therapeutic for a whole cluster of carb-related problems: high blood sugar (or the rollercoaster of highs and lows), insulin resistance, and all the related issues. These issues can make weight loss difficult or impossible, but on the flip side, addressing them through diet can make it easier and more pleasant than you ever thought could happen! On the other hand, though, there are a lot of myths and half-truths floating around about diet, exercise, and carb metabolism. So here’s a quick review of what it all means, and the evidence supporting various different complementary strategies for improving your carb tolerance (preview: it’s so much more than dietary carbs). Note: This article is not written for diabetics. Diabetes is a very complicated disease and strategies that are right for other people might not be appropriate. If you have diabetes, see a doctor! What Is “Carb Tolerance”/Insulin Sensitivity? (If you already know how insulin and glucose work, this section has nothing new for you; just skip down to the next one) Very simply put, insulin sensitivity (or “carb tolerance” in everyday language) is a healthy hormonal state that allows your body to digest and store carbohydrates without a problem. In healthy people, here’s how it works: You eat something with carbs (let’s say a potato, but it could be anything). Your digestive system breaks down the starch in that potato into glucose. Glucose is a simple sugar – this is the form of carbohydrate that you’ll either use for energy or store as fat. Your blood sugar temporarily rises as the glucose enters the bloodstream. This is not a big problem, because… Insulin (produced in the pancreas) Continue reading >>
The Connection Between Insulin Resistance And The High-carb, Low-fat Diet
Dr. Tim Noakes, a well-respected scientist, researcher, physician and professor at the University of Cape Town, South Africa, is one of the world’s foremost experts on low-carb diets Legal action was taken to strip him of his medical license for promoting the low-carb diet. It’s the first time in history that a diet has been put before a legal jury to decide whether or not it’s correct A low-carb, high-fat diet is crucial for preventing or reversing insulin resistance and type 2 diabetes; treating type 2 diabetes with insulin is one of the worst mistakes you can make By Dr. Mercola Dr. Tim Noakes, a well-respected scientist, researcher, physician and professor at the Division of Exercise Science and Sports Medicine at the University of Cape Town, South Africa, is one of the world's foremost experts on low-carb diets. In fact, he was instrumental in getting the low-carb diet revolution off the ground. He's also an accomplished athlete. As a long-distance endurance runner with 70 marathons under his belt, he had long promoted high-carb diets, himself consuming 400 grams of carbs a day or more when preparing for a race. Eventually, he discovered this wasn't the best way to improve athletic endurance and health, and ended up writing a number of popular books on low-carb diets. From High to Low Carb Noakes graduated from medical school in 1974. At the time, he was also running, and this was when the high carbohydrate diet really started to become popularized. Following the advice of one of his professors at the cardiology unit where he worked, he changed to a high-carb diet and began promoting it in his writings, including the book, "Lore of Running," which was widely read. "There it says that you must eat lots of carbohydrates for both health and performance. I contin Continue reading >>
High Fat Diet Induces Central Obesity, Insulin Resistance And Microvascular Dysfunction In Hamsters
Volume 82, Issue 3 , November 2011, Pages 416-422 High fat diet induces central obesity, insulin resistance and microvascular dysfunction in hamsters Microvascular dysfunction is an early finding in obesity possibly related to co-morbidities like diabetes and hypertension. Therefore we have investigated changes on microvascular function, body composition, glucose and insulin tolerance tests (GTT and ITT) on male hamsters fed either with high fat (HFD, n=20) or standard (Control, n=21) diet during 16weeks. Total body fat and protein content were determined by carcass analysis, aorta eNOS and iNOS expression by immunoblotting assay and mean blood pressure (MAP) and heart rate (HR) by an arterial catheter. Microvascular reactivity in response to acetylcholine and sodium nitroprusside, functional capillary density (FCD), capillary recruitment induced by a hyperinsulinemic status and macromolecular permeability after 30min ischemia was assessed on either cheek pouch or cremaster muscle preparations. Compared to Control, HFD animals have shown increased visceral fat (6.00.8 vs. 13.80.6g/100g BW), impaired endothelial dependent vasodilatation, decreased FCD (11.31.3 vs. 6.81.2/field) and capillary recruitment during hyperinsulinemia and increased macromolecular permeability after ischemia/reperfusion (86.45.2 vs.105.25.1leaks/cm2), iNOS expression and insulin resistance. MAP, HR, endothelial independent vasodilatation and eNOS expression were not different between groups. Our results have shown that HFD elicits an increase on visceral fat deposition, microvascular dysfunction and insulin resistance in hamsters. We have studied microcirculatory effects of high fat diet in hamsters High fat diet blunted arteriolar response to acetylcholine and induced iNOS expression in aorta. Continue reading >>
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 >>
Dear Mark: Does Eating A Low Carb Diet Cause Insulin Resistance?
157 Comments Despite all the success you might have had with the Primal way of life, doubts can still nag at you. Maybe it’s something you read, or something someone said to you, or a disapproving glance or offhand comment from a person you otherwise respect, but it’s pretty common when you’re doing something, like giving up grains, avoiding processed food, or eating animal fat, that challenges deeply-and-widely held beliefs about health and wellness. It doesn’t really even matter that you’re losing weight or seem to be thriving; you may still have questions. That’s healthy and smart, and it’s totally natural. A question I’ve been getting of late is the effect of reducing carb intake on insulin sensitivity. It’s often bandied about that going low carb is good for folks with insulin resistance, but it’s also said that low carb can worsen insulin resistance. Are both true and, if so, how do they all jibe together? That’s what the reader was wondering with this week’s question: Hi Mark, I’ve been Primal for a few months now and love it. Lowering my carbs and upping my animal fat helped me lose weight and gain tons of energy (not too shabby for a middle-aged guy!). However, I’m a little worried. I’ve heard that low carb diets can increase insulin resistance. Even though I’ve done well and feel great, should I be worried about insulin resistance? Do I need to increase my carb intake? I always thought low carb Primal was supposed to improve insulin function. Vince Going Primal usually does improve insulin sensitivity, both directly and in a roundabout way. It improves directly because you lose weight, you reduce your intake of inflammatory foods, you lower systemic inflammation (by getting some sun, smart exercise, omega-3s, and reducing or dea Continue reading >>
High-fat Diets Cause Insulin Resistance Despite An Increase In Muscle Mitochondria
High-fat diets cause insulin resistance despite an increase in muscle mitochondria We are experimenting with display styles that make it easier to read articles in PMC. The ePub format uses eBook readers, which have several "ease of reading" features already built in. The ePub format is best viewed in the iBooks reader. You may notice problems with the display of certain parts of an article in other eReaders. Generating an ePub file may take a long time, please be patient. High-fat diets cause insulin resistance despite an increase in muscle mitochondria Chad R. Hancock, Dong-Ho Han, [...], and John O. Holloszy It has been hypothesized that insulin resistance is mediated by a deficiency of mitochondria in skeletal muscle. In keeping with this hypothesis, high-fat diets that cause insulin resistance have been reported to result in a decrease in muscle mitochondria. In contrast, we found that feeding rats high-fat diets that cause muscle insulin resistance results in a concomitant gradual increase in muscle mitochondria. This adaptation appears to be mediated by activation of peroxisome proliferator-activated receptor (PPAR) by fatty acids, which results in a gradual, posttranscriptionally regulated increase in PPAR coactivator 1 (PGC-1) protein expression. Similarly, overexpression of PPAR results in a large increase in PGC-1 protein in the absence of any increase in PGC-1 mRNA. We interpret our findings as evidence that raising free fatty acids results in an increase in mitochondria by activating PPAR, which mediates a posttranscriptional increase in PGC-1. Our findings argue against the concept that insulin resistance is mediated by a deficiency of muscle mitochondria. Keywords: mitochondrial biogenesis, mitochondrial dysfunction, PPAR, skeletal muscle, PGC-1 It has b Continue reading >>
What Causes Insulin Resistance? Lipid Overload
Over the past year I have interacted with hundreds of people with diabetes, and have come to learn one very important lesson that has changed my view of diabetes altogether. This realization came to me early on in my career as a nutrition and fitness coach for people with diabetes, and continues to hold true. While insulin resistance is a condition that is most commonly associated with type 2 diabetes, an increasing body of evidence is now shedding light on the fact that insulin resistance is a common thread that underlies many health conditions previously unassociated with blood sugar, including (but not limited to) heart disease, diabetes, atherosclerosis, the metabolic syndrome, obesity and cancer. What that means is simple: insulin resistance significantly increases your risk for the development of a collection of health conditions that can significantly reduce your quality of life and decrease your life expectancy. Watch this video for a synopsis of the causes of insulin resistance: What is insulin and why should you care? Insulin is a hormone which is released by the pancreas in response to rising blood glucose. When you consume carbohydrates, the glucose that enters the bloodstream knocks on the door of the beta cells in the pancreas as a signal to make insulin. Insulin serves as the key that unlocks the door to allow glucose to enter body tissues. Insulin tells your cells “Yoo hoo! Pick up this glucose. It’s all over the place.” Without insulin, cells in the liver, muscle, and fat have a difficult time vacuuming up glucose from the blood. These tissues are capable to vacuuming up only a small percentage (5-10%) of the glucose in circulation without the help of insulin. When insulin is present, the amount of glucose that can be transported into tissues sign Continue reading >>
What Causes Insulin Resistance?
Michael: You wrote: ” Part of the question in my mind are the relative benefits of higher HDL vs lower LDL; a topic I would love to see taken up on a NF video.” I have suggested that this be a topic of future videos. In the meantime, below is some information I’ve gathered about HDL which may be helpful to you. . **************** I am not an expert on the topic of HDL, but some of my favorite NutritionFacts forum members and some experts have had a thing or two to say on the matter. BOTTOM LINE: I synthesize the information below to mean we do not need to worry about HDL levels or HDL falling in the context of a whole plant food based diet, when LDL goes down or is already at a healthy level. . In other words, if you have high/unsafe cholesterol levels (total and LDL) overall, then also having high HDL can be protective (especially if you got that high HDL through exercise or some other healthy behavior rather than diet). But in the face of healthy LDL levels, the HDL level doesn’t seem to matter. I may be wrong about this, but see what you think. ************************************ . First, check out the following article from heart health expert Dean Ornish. He does a great job of explaining the role of HDL and when we need to worry about it’s levels vs when we do not. “A low HDL in the context of a healthy low-fat diet has a very different prognostic significance than a low HDL in someone eating a high-fat, high-cholesterol diet.” . Two of our more knowledgable forum particpants, Gatherer and Darryl, have put together for us some of the strongest evidence–a list of good studies. Gatherer wrote (from comment ) : . “”Don’t put too much stock in HDL levels. Here is a news release “Raising ‘good’ cholesterol doesn’t protect against heart di Continue reading >>
High Fat Diet Induces Brain Insulin Resistance And Cognitive Impairment In Mice
Volume 1863, Issue 2 , February 2017, Pages 499-508 High fat diet induces brain insulin resistance and cognitive impairment in mice Consumption of high fat diet and sugary drink (HFS) leads to abnormal metabolic phenotype in mice Feeding of HFS also leads to impairment of brain insulin signaling linked with neuroinflammation. Insulin resistant due to HFS associated with biochemical changes in markers related with Alzheimer disease pathology. High fat diet-induced obesity is associated with insulin resistance (IR) and other chronic, diet related illnesses, including dementia. Alzheimer disease is the most common form of dementia, and is characterized by the presence of amyloid plaques and neurofibrillary tangles in brain. This study was designed to determine whether diet-induced changes in peripheral insulin sensitivity could contribute to alterations in brain insulin signaling and cognitive functions. Six week old, male C57BL/6NHsd mice were randomly assigned a high fat diet (40% energy from fat) with 42g/L liquid sugar (HFS) added to the drinking water or a normal chow diet (12% energy from fat) for 14weeks. Metabolic phenotypes were characterized for energy expenditure, physical activity, and food intake, and glucose and insulin tolerance tests. In addition, we examined the changes in protein expression related to brain insulin signaling and cognitive function. Mice fed HFS exhibited a statistically significant increase in obesity, and lower glucose and insulin tolerance as compared to animals fed the normal chow diet. In brain, HFS elicited IR as evidenced by a significant decrease in tyrosine phosphorylation of insulin receptor and an increase serine phosphorylation of IRS-1. These changes were accompanied by inflammatory (NFB, JNK) and stress responses (p38 MAPK, Continue reading >>
Effect Of High Fat Diet On Insulin Resistance: Dietary Fat Versus Visceral Fat Mass.
Effect of high fat diet on insulin resistance: dietary fat versus visceral fat mass. This article has been cited by other articles in PMC. The purpose of the present study was to determine whether chronic high-fat diet (HF) induces insulin resistance independently of obesity. We randomly divided 40 rats into two groups and fed them either with a HF or with a high-carbohydrate diet (HC) for 8 weeks. Whole body glucose disappearance rate (Rd) was measured using a euglycemic hyperinsulinemic clamp. Firstly, we defined whether insulin resistance by HF was associated with obesity. Plasma glucose and triglyceride concentrations were significantly increased in HF. Rd was decreased (10.6+/-0.2 vs. 9.1+/-0.2 mg/kg/min in HC and HF, respectively) and the hepatic glucose output rate (HGO) was increased in HF (2.2+/-0.3 vs. 4.5+/-0.2 mg/kg/min in HC and HF, respectively). Rd was significantly correlated with %VF (p<0.01). These results implicate that visceral obesity is associated with insulin resistance induced by HF. In addition, to define whether dietary fat induces insulin resistance regardless of visceral obesity, we compared Rd and HGO between groups 1) after matching %VF in both groups and 2) using an ANCOVA to adjust for %VF. After matching %VF, Rd in HF was significantly decreased by 14% (p<0.001) and HGO was significantly increased by 110% (p<0.001). Furthermore, statistical analyses using an ANCOVA also showed Rd for HF was significantly decreased even after adjusting %VF. In conclusion, we suggest that dietary fat per se could induce insulin resistance in rats fed with chronic HF independently of obesity. The Full Text of this article is available as a PDF (77K). Articles from Journal of Korean Medical Science are provided here courtesy of Korean Academy of Medical Sci Continue reading >>
The Ketogenic Diet And Insulin Resistance
We recently touched on how you can use the ketogenic diet to control symptoms of diabetes such as elevated glucose and triglycerides. In this article, we examine research showing the impact that the ketogenic diet has on levels of the hormone insulin, a key regulator of blood sugar in the body. What is Insulin’s Role in the Body? Before we look at the research, we need to know our main players. Insulin is a protein-based hormone produced by beta-cells located in the pancreas. The pancreas, which is located under the stomach, also produces enzymes that aid with digestion. Insulin’s primary purpose is to regulate the metabolism of fats and carbohydrates. The digestive system breaks down carbohydrates, such as sugars and starches, into a molecule called glucose. This compound can be used by cells to produce energy through a process called cellular respiration. Insulin allows cells in the body absorb glucose, ultimately lowering levels of glucose in the blood stream. After a meal is consumed, blood glucose levels increase and the pancreas responds by releasing insulin into the blood. Insulin assists fat, liver, and muscle cells absorb glucose from the blood, resulting in lower levels of blood glucose. Insulin stimulates liver and muscle tissues to store excess glucose as a molecule called glycogen and also reduces glucose production by the liver. When blood sugar is low, the hormone glucagon (produced by alpha-cells in the pancreas) stimulate cells to break down glycogen into glucose that is subsequently released into the blood stream. In healthy people who do not have type II diabetes, these functions allow levels of blood glucose and insulin to stay in a normal range. What Is Insulin Resistance and Why Is It a Problem? Unfortunately, for many Americans and other peopl Continue reading >>
Diet And Diabetes: Why Saturated Fats Are The Real Enemy
Diet and Diabetes: Why Saturated Fats Are the Real Enemy This is the seventh article in our Controversies series and the third piece focusing on the subject of fats. Today, we are going to explore the very important relationship between saturated fat intake and the onset of diabetes. As we mentioned in The Ultimate Guide to Saturated Fats , Once we control for weight, alcohol, smoking, exercise and family history, the incidence of diabetes is significantly associated with the proportion of saturated fat in our blood. Today we will take a deep dive to fully understand why there is such a strong link between diabetes and saturated fat consumption. We will also discuss how a plant-based diet may protect you from (or even reverse!) the disease. Insulin resistance is a hallmark of both prediabetes and type 2 diabetes. So what is insulin resistance exactly (and why is it important)? Insulin is what permits glucose (sugar) in the blood to enter our (muscle) cells. In essence, insulin unlocks the door, allowing the glucose to come in. If there is no insulin at all (the case of type 1 diabetes), the blood sugar hangs out in the bloodstream because it cannot get inside. That causes the blood sugar levels to rise. But what happens if the insulin is there but is simply not working properly? In that case, the lock to the cell door is blocked. This is what is called insulin resistance. So what causes insulin resistance in the first place? Fat build-up inside (muscle) cells creates toxic fatty breakdown products and free radicals that block the insulin-signaling process, close the glucose gate, and make blood sugar levels rise. In fact, insulin resistance can occur in 180 short minutes (just 3 hours!) after the consumption of fat. The process of insulin resistance, caused by the buil Continue reading >>
High-fat Diets Promote Insulin Resistance Through Cytokine Gene Expression In Growing Female Rats - Sciencedirect
Get rights and content To determine if tumor necrosis factor (TNF-) and interleukin-6 (IL-6). IL-6 gene expression is influenced by amount and source of dietary fat, 30 weanling female rats were randomly assigned to a moderate-fat soybean oil (MFS; 22% of total energy fed as fat), high-fat (HF) soybean oil (HFS; 39% of total energy fed as fat), or HF tallow (HFT; 39% of total energy fed as fat) diet treatments. Oral glucose tolerance tests (OGTT) were conducted serially over 10 weeks of treatment. HFT and HFS rats gained more weight and had greater body fat than the MFS rats fed similar amounts of energy. Both groups of HF-fed rats had greater (P<.05) insulin resistance (homeostasis model assessment) than MFS-fed rats. TNF- mRNA abundance quantified by real-time reverse transcriptase-polymerase chain reaction was greater (P<.05) in liver and lower (P<.05) in adipose tissue in HFT compared to HFS and MFS rats. There were positive correlations (P<.05) between hepatic TNF- mRNA and insulin resistance, and negative correlations between insulin sensitivity and hepatic TNF- mRNA and hepatic IL-6 mRNA. During Week 3 and Week 6 OGTTs, hyperinsulinemic responses were observed in the HFT group, after which, on Week 9, insulin secretion was diminished in response to the OGTT, suggesting impaired pancreatic insulin secretion. HFS rats exhibited insulin resistance on Week 9 OGTT. In summary, an HFT diet fed to growing female rats caused insulin resistance associated with increased hepatic TNF- mRNA leading to pancreatic insufficiency. Early-onset insulin resistance related to the inflammatory process in obesity is influenced by the amount and type of fat in the diet. Continue reading >>