How Permanent Is The Effect Of Intermittent Fasting On Insulin Resistance?
There are tons of questions about intermittent fasting, like these: How permanent is the effect of intermittent fasting on insulin resistance? Does whey protein supplements help lower blood sugars? Dr. Jason Fung is one of the world’s leading experts on fasting for weight loss or diabetes reversal. Here are a his answers to those questions and more: Fasting and insulin resistance Dr Fung, I have a few questions: 1. How permanent is the IF on the insulin resistance? After you lower the insulin resistance through a regimen of fasting, is it sustainable or you have to do it for life. As you mentioned, most weight loss diet are not reversible. So I wonder whether IF is sustainable. 2. In this study, it is mentioned that whey protein helps to lower blood sugar. For me, I take Whey after a gym regimen to help to build muscles. I am TD2. Is it harmful to take whey (not excessive – just about one spoonful provided by the Whey protein can). 3. What about Monk Fruit (natural – not processed). Is it OK to drink that or mix it with your drink? Seng Dr. Jason Fung: 1. It is not permanent. It’s like taking a bath. You can’t do it once and expect to be clean forevere. 2. I don’t recommend it. Stick to real food. 3. No. Aspirin Dr. Fung, thanks for the reply to previous questions, now have one about baby aspirin. I’ve been taking a daily baby aspirin in addition to all the oils for blood lubricity, and with all the bad press I’ve been reading lately I’m beginning to question the wisdom of that. I’m thinking the oils I’m taking : fish oils, avocado oils, olive oils, Vit E in tocotrienol form, and Vit. D’s, are enough to keep blood lubed up plenty good. Question is do I really need the baby aspirin. I know from your book “The Obesity Code” that you don’t see Continue reading >>
You Are “when” You Eat: The Benefits Of Intermittent Fasting (video)
Intermittent fasting is term coined by the research world that refers to an extended duration of minimal calorie intake. Believe it or not, humans are evolutionarily adapted to performing intermittent fasts – our ancestors performed extended fasts whenever food was unavailable, and feasted only when they could procure enough food to eat. However, in our modern world of abundance, deliberately fasting for an extended period of time is anything but “normal.” Fasting goes against every morsel of modern life, and is in direct opposition to the abundance-based food culture that we have worked so hard to create. In our world of fast food, on-demand food delivery and 24-hour convenience stores, choosing not to eat food can seem strange indeed. I spent my entire graduate career investigating the effects of intermittent fasting in rodents, in order to understand why calorie restriction and intermittent fasting are the gold standards for improving insulin sensitivity. As a result of this active body of research, tens of thousands of people across the world engage in intermittent fasting on a weekly basis, as a means of improving their body composition, losing fat mass, shedding pounds or observing a religious holiday. The research world has taken a large interest in calorie restriction and intermittent fasting, for the explicit purpose of identifying cellular mechanisms that may retard the aging process and promote excellent metabolic health. And in the process of studying intermittent fasting, researchers have uncovered a laundry list of health benefits that confuse even the most educated professors. The truth is that humans have been fasting for thousands of years. Modern research is playing catch-up, in order to understand why the health benefits are so impressive. The M Continue reading >>
Intermittent Fasting: An Effective Tool For Weight Loss
Intermittent Fasting: An Effective Tool for Weight Loss Intermittent fasting (IF) is a fascinating topic for a variety of reasons.IF is relatively simple, its fairly easy to stick to, its cheap, and it has a vast array of health benefits, including weight loss. Most of us have grown up thinking that skipping meals is bad. We believe that it slows down our metabolism, puts our body in starvation mode, and makes us store more body fat. However, research shows that short-term intermittent fasting, whether its for part of the day or the entire 24 hours, can actually boost our metabolism , increase fat loss, and improve our overall health. I recently spoke with Dr. Anthony Balduzzi, a naturopathic physician and founder of The Fit Father Project ,who is a big proponent of IF. Heres what he told me: I recommend that almost every healthy human on the planet do at least some fasting in their weekly routine. I personally do a 24-hour fast once a week every week, and I plan on doing that for the rest of my life. Its just incredibly effective and healthy for so many reasons. ( Check out my full interview with Dr. Balduzzi here .) So, what exactly is intermittent fasting and should you give it a try? Lets take a deeper look at IF and all that it has to offer. IF is not a diet. Rather, its a pattern of eating that focuses on when you eat as opposed to what you eat. (IF is actually part of nutrient timing theory, which you can read more about here .) During intermittent fasting, you compress your eating window into a set number of hours and fast for the rest of the day. Typically people do this anywhere from a day to a few days a week, though its possible to follow some form of intermittent fasting every day. (Side Note: While short-term fasting can speed up your metabolism, research Continue reading >>
The Sweet Spot For Intermittent Fasting
The Sweet Spot for Intermittent Fasting Lower insulin means greater fat loss Intermittent fasting — the practice of going without food for some (undefined) period of time — has many health benefits. It can help prevent heart disease, speed fat loss, and slow or reverse aging. There are a number of physiological mechanisms involved. It reduces inflammation and oxidative stress, leads to increased numbers and quality of mitochondria, and increases autophagy, the cellular self-cleansing process. Many of the beneficial effects are entwined with lower levels of insulin. The function of insulin is to promote energy storage and the growth of the organism. When insulin is increased, fat is stored in fat cells, and other cells take up glucose from the blood. Most importantly, when insulin is increased, lipids can’t leave fat cells. Since fat loss is all about getting lipids out of fat cells to be burned, losing fat requires some attention to how diet, exercise, and fasting cause insulin to rise or fall. Take a look at the following graph, taken from a paper by Volek et al. It shows that even small increases in insulin, within the normal range, virtually abolish lipolysis, or the breakdown of fat. This is where intermittent fasting comes in, as one of its effects is to lower insulin levels and thus increase lipolysis. The question is, how long do you need to fast before insulin comes down? Eating causes insulin to rise, the amount of the rise being dependent on a number of factors, such as type and amount of food eaten and the insulin sensitivity of the person doing the eating. High amounts of carbohydrates and lower insulin sensitivity cause a greater rise in insulin. Insulin increases and stays higher for several hours after eating — that is, during the “fed” state. Continue reading >>
10 Evidence-based Health Benefits Of Intermittent Fasting
Intermittent fasting is an eating pattern where you cycle between periods of eating and fasting. Numerous studies show that it can have powerful benefits for your body and brain. Here are 10 evidence-based health benefits of intermittent fasting. When you don't eat for a while, several things happen in your body. For example, your body initiates important cellular repair processes and changes hormone levels to make stored body fat more accessible. Here are some of the changes that occur in your body during fasting: Insulin levels: Blood levels of insulin drop significantly, which facilitates fat burning (1). Human growth hormone: The blood levels of growth hormone may increase as much as 5-fold (2, 3). Higher levels of this hormone facilitate fat burning and muscle gain, and have numerous other benefits (4, 5). Cellular repair: The body induces important cellular repair processes, such as removing waste material from cells (6). Gene expression: There are beneficial changes in several genes and molecules related to longevity and protection against disease (7, 8). Many of the benefits of intermittent fasting are related to these changes in hormones, gene expression and function of cells. When you fast, insulin levels drop and human growth hormone increases. Your cells also initiate important cellular repair processes and change which genes they express. Many of those who try intermittent fasting are doing it in order to lose weight (9). Generally speaking, intermittent fasting will make you eat fewer meals. Unless if you compensate by eating much more during the other meals, you will end up taking in fewer calories. Additionally, intermittent fasting enhances hormone function to facilitate weight loss. Lower insulin levels, higher growth hormone levels and increased amoun Continue reading >>
How Intermittent Fasting Can Increase Weight Loss
Intermittent fasting, without restricting overall calorie intake, has been found to reduce weight and improve metabolism. A new investigation hunts down the molecular mechanisms behind these physiological benefits. Our modern lifestyle, combined with longer waking hours, means that the enforced period of fasting while we sleep has steadily been reduced. This, along with the poor-quality Western diet and more time spent sedentary, has dramatically increased the prevalence of obesity and metabolic disease. Over recent years, fasting has been shown to impart a number of health benefits. Many clinicians hope that by modifying aspects of fasting — such as how long to fast for, what to eat between fasts, and when to fast — it may be possible to design methods of combating obesity and metabolic disorders. The rise of periodic fasting Intermittent fasting is believed to share many of its health benefits with prolonged fasting. It has, for instance, been shown to reduce oxidative stress and inflammation. Other studies have demonstrated that intermittent fasting increases insulin sensitivity and protects nerve cells from certain types of damage. It may also slow aging and reduce the risk of age-related diseases. Intermittent fasting without a reduction in calorie intake can be a preventative and therapeutic approach against obesity and metabolic disorders." Study co-author Kyoung-Han Kim Because of these, and other, recent findings, the so-called 5:2 diet — which involves 5 days of normal eating followed by 2 days of fasting — has become popular. Evidence in favor of intermittently restricting calorie intake is growing, but the mechanisms through which it imparts its benefits are still unclear. Recently, a research team led by Hoon-Ki Sung — of the Department of Laborat Continue reading >>
Intermittent Fasting Finally Becoming Mainstream Health Recommendation
It is nice to see the intermittent fasting approach that I have recommended for some time now is starting to catch on. This is no surprise to me as it is one of the most powerful interventions I know of to move your body into fat burning mode and have your hunger nearly magically disappear. It is a powerful tool to help you keep a healthy weight. In a new diet book, The Fast Diet: Lose Weight, Stay Healthy, and Live Longer with the Simple Secret of Intermittent Fasting, Dr. Michael Mosley1 suggests the best way to lose weight is to eat normally for five days a week, and fast for two. On fasting days, he recommends cutting your food down to ¼ of your normal daily calories, or about 600 calories for men and about 500 for women, along with plenty of water and tea. Dr. Mosley himself claims to have lost 19 pounds in two months by following this recommendation. I lost about seven pounds when I implemented the approach last year, but the most amazing aspect is not the weight loss, it's the absence of hunger and sugar cravings once you are fat adapted. Your desire to eat unhealthy foods seems to disappear; at least that was my experience. I prefer to think of intermittent fasting as a lifestyle rather than a diet. It's a way of living and eating that can help you live a longer, healthier life. I promoted the health benefits of intermittent fasting well before it hit the mainstream, and have been experimenting with different types of scheduled eating in my own life for the past two years. I currently restrict my eating to a 6-7 hour window each day. In the featured BBC interview,2 Dr. Mosley also points out the importance of high-intensity interval training (HIIT) — especially in conjunction with fasting — and how sheer inactivity is actually more detrimental to your healt Continue reading >>
Intermittent Fasting And Diabetes: Can If Improve Insulin Sensitivity?
Type 2 diabetes is a diseases that kills many. Intermittent fasting has been indicated as a potential treatment, but does it stand up to scrutiny? Type 2 Diabetes is an incredibly damaging disease that causes a huge amount of damage to both life and to our national healthcare expenses. Diabetes is the seventh leading cause of death in the United States. It has annual costs of $245,000,000,000. This is a huge problem for our nation and for 29.1 million people. There was early on some evidence in rats and mice that intermittent fasting could help with insulin sensitivity and potentially with diabetes, and the question is whether or not that same effect is seen in humans. First things first we need to briefly discuss how Type 2 Diabetes develops. (Remember I am not a doctor or medical professional) First of all we will discuss how insulin functions in a healthy individual and then how it is warped in a person who develops Type 2 diabetes. Healthy: A person consumes foods that increase blood sugar (especially carbohydrates) The pancreas (specifically the beta islet cells) read the increase in blood glucose and release insulin. Your cells see the increase in insulin and take it as a signal to bring the glucose in the blood into the cell for energy Blood sugar levels fall to normal. Diseased: A person consumes food (frequently or of the type that chronically raises blood sugar levels) The pancreas reads the chronically elevated levels and produces more and more insulin The cells gradually become ‘resistant’ to the signal of the insulin and it takes more and more insulin for them to bring in the gluocose. Pancreas produces more insulin in order to try to drive the glucose into the resistant cells The elevated insulin levels damage the pancreas’ ability to produce insulin Continue reading >>
Effects Of Intermittent Fasting On Health Markers In Those With Type 2 Diabetes: A Pilot Study
Go to: Abstract To determine the short-term biochemical effects and clinical tolerability of intermittent fasting (IF) in adults with type 2 diabetes mellitus (T2DM). We describe a three-phase observational study (baseline 2 wk, intervention 2 wk, follow-up 2 wk) designed to determine the clinical, biochemical, and tolerability of IF in community-dwelling volunteer adults with T2DM. Biochemical, anthropometric, and physical activity measurements (using the Yale Physical Activity Survey) were taken at the end of each phase. Participants reported morning, afternoon and evening self-monitored blood glucose (SMBG) and fasting duration on a daily basis throughout all study stages, in addition to completing a remote food photography diary three times within each study phase. Fasting blood samples were collected on the final days of each study phase. At baseline, the ten participants had a confirmed diagnosis of T2DM and were all taking metformin, and on average were obese [mean body mass index (BMI) 36.90 kg/m2]. We report here that a short-term period of IF in a small group of individuals with T2DM led to significant group decreases in weight (-1.395 kg, P = 0.009), BMI (-0.517, P = 0.013), and at-target morning glucose (SMBG). Although not a study requirement, all participants preferentially chose eating hours starting in the midafternoon. There was a significant increase (P < 0.001) in daily hours fasted in the IF phase (+5.22 h), although few attained the 18-20 h fasting goal (mean 16.82 ± 1.18). The increased fasting duration improved at-goal (< 7.0 mmol/L) morning SMBG to 34.1%, from a baseline of 13.8%. Ordinal Logistic Regression models revealed a positive relationship between the increase in hours fasted and fasting glucose reaching target values (χ2 likelihood rat Continue reading >>
What Does Fasting Do To Insulin?
A common thread among many dietary plans is compressing eating times. On the one hand, some plans narrow periods to two to three meals per day, with substantial time gaps in between (i.e. time-restricted feeding). Variation include other strategies that suggest eating normally for a few days, then avoiding food entirely for a few days (i.e. intermittent fasting). On the other hand, some diet plans encourage eating several meals throughout the day (i.e, “grazing”; 6-8 small meals per day). Because elevated insulin is one of the most, if not the most, relevant factor in developing insulin resistance, a highly rational strategy is to follow a dietary plan that incorporates periods of time throughout the day wherein insulin is low. This philosophy immediately suggests that frequent eating is less effective than less frequent eating—indeed, three meals per day is better than six [1]—but are fewer than three meals best of all? Maybe. Fasting’s Effectiveness Partially Depends on How It’s Done Time-restricted feeding and intermittent fasting strategically include periods of deliberate food avoidance. The evidence regarding its efficacy in improving insulin sensitivity is valid, though it partially depends on how it’s done. Two studies used this idea by having study subjects eat normally one day (i.e. unrestricted) and essentially fast the entire second day (i.e., alternate-day fasting), repeated seven times over a two-week period and found conflicting results—one reporting an improvement in insulin sensitivity [2], while the other observed no benefit [3]. An alternative strategy, wherein the person confines eating to a specific window of time each day (e.g., eating breakfast and dinner only [4], or lunch and dinner only [5]) yielded robust improvements in insuli Continue reading >>
17: Healing Insulin Resistance, Benefits Of Shorter Fasts, Fasting Again, Extended Fasting Vs. If For Weight Loss, Electrolyte Imbalance, Coffee Enemas
HOT TOPIC: What are the signs a patient can look for that indicate there is healing happening to their insulin resistance? I just finished up my first extended fast at 67 hours thanks to the information that you and Megan share on your awesome podcast. I’m down 3 pounds, blood sugar 63, blood ketones 6.6. I had improved blood pressure, amazing mental clarity and even ran my fastest 5K ever. Wow! I’m going to keep extended fasting as part of my routine along with regular intermittent fasting. I have a question for you guys that I haven’t heard addressed yet. Other than measuring changes in blood glucose and ketone levels, how would someone know they are improving their insulin resistance? Are there ways you quantify this in your patients at IDM? Thanks so much for all that you do. I am so very grateful that I found you guys! NOTICE OF DISCLOSURE: Paid sponsorship 1. What are the hormone improvements and adaptations that take place doing shorter fasts of 24-36 hours? I have read Keto Clarity, The Obesity Code and The Complete Guide to Fasting, so thanks for all these great resources. In The Obesity Code, Dr. Fung writes about a lot of adaptations that happen during fasting including a rise in epinephrine. But according to the book, those adaptations do not kick in until around Day 3 or 4 of extended fasting. So what I want to know is what hormonal improvements or adaptations take place during an intermittent or alternate day fasting period of 24-36 hours? Keep up the great work! I’ve been intermittent fasting for 10 weeks and I’m down 20 pounds! GIVE YOUR ELECTROLYTES A SUGAR-FREE BOOST NOTICE OF DISCLOSURE: Paid sponsorship 2. Why am I not getting the same benefits from fasting now that had I previously when I fasted? What can I do about it? Many years ago, I w Continue reading >>
Fasting Physiology – Part Ii
There are many misconceptions about fasting. It is useful to review the physiology of what happens to our body when we eat nothing. Physiology Glucose and fat are the body’s main sources of energy. If glucose is not available, then the body will adjust by using fat, without any detrimental health effects. This is simply a natural part of life. Periods of low food availability have always been a part of human history. Mechanisms have evolved to adapt to this fact of Paleolithic life. The transition from the fed state to the fasted state occurs in several stages. Feeding – During meals, insulin levels are raised. This allows uptake of glucose into tissues such as the muscle or brain to be used directly for energy. Excess glucose is stored as glycogen in the liver. The post-absorptive phase – 6-24 hours after beginning fasting. Insulin levels start to fall. Breakdown of glycogen releases glucose for energy. Glycogen stores last for roughly 24 hours. Gluconeogenesis – 24 hours to 2 days – The liver manufactures new glucose from amino acids in a process called “gluconeogenesis”. Literally, this is translated as “making new glucose”. In non-diabetic persons, glucose levels fall but stay within the normal range. Ketosis – 2-3 days after beginning fasting – The low levels of insulin reached during fasting stimulate lipolysis, the breakdown of fat for energy. The storage form of fat, known as triglycerides, is broken into the glycerol backbone and three fatty acid chains. Glycerol is used for gluconeogenesis. Fatty acids may be used for directly for energy by many tissues in the body, but not the brain. Ketone bodies, capable of crossing the blood-brain barrier, are produced from fatty acids for use by the brain. After four days of fasting, approximately 75 Continue reading >>
Intermittent Fasting Increases Peripheral But Not Hepatic Insulin Sensitivity
Intermittent Fasting Increases Peripheral but not Hepatic Insulin Sensitivity Cycles of feast and famine wer Cycles of feast and famine were common in earlier days. To guarantee survival, metabolic adaptations to these opposing feeding states are indispensable. It has been shown that intermittent fasting (IF) in humans increases whole body insulin sensitivity without affecting body composition or body weight. Whether this is caused solely by an increase in peripheral or hepatic insulin sensitivity or both is not known. To explore the effects of IF on glucose metabolism, we studied glucose fluxes after a period of two weeks of IF and a standardized eucaloric diet (SD). Eight healthy lean male volunteers underwent a two step (insulin infusion 10 mU/m2 x min and 40 mU/m2 x min) hyperinsulinemic euglycemic clamp using stable isotopes after two weeks of a SD and after two weeks of IF. Caloric intake per 48 hrs was similar to avoid changes in body weight. Data are presented as median [min-max] and comparisons were calculated using the Wilcoxon Signed Rank Test. Basal plasma glucose levels tended to be lower after SD compared to IF (4.7 [4.0 - 4.9] vs. 4.8 [4.7 - 5.3] mmol/L respectively, P = 0.09. Basal endogenous glucose production (EGP) did not change (SD 10.4 [9.6 - 13.9] µmol/kg x min vs. IF 11.4 [10.0 - 13.9] µmol/kg x min, P = 0.67). EGP during the low dose insulin infusion was equal after SD and IF (1.9 [0 - 6.7] vs. 2.6 [1.7 - 5.9] umol/kg x min resp, P = 0.575) while peripheral glucose uptake (Rd) was significantly lower after SD compared to IF (21.4 [16.5 - 35.7] vs. 27.3 [20.4 - 36.5] µmol/kg x min resp., P = 0.05). During the high dose insulin infusion, no differences were found in EGP and Rd after SD or IF. No differences were observed in lipid and glucose oxi Continue reading >>
Intermittent Fasting Improves Insulin Sensitivity Even Without Weight Loss
Though you may not have heard the term that often, insulin resistance is a big health problem these days. What insulin resistance means in practice is that normal amounts of insulin are not enough to produce an insulin response – a signal for cells to take up glucose from the blood. The result of prolonged insulin resistance is diabetes, and everyone has heard of diabetes. Since diabetes is really the end result of a long process (which has the ultimate end result of death), it's much easier and more economic to tackle insulin resistance before things get out of hand. Several small meals or a few big ones? The traditional wisdom says that the key to staying healthy, lean and fit is to eat several small meals a day. "Keep blood sugar levels constant" and "breakfast is the most important meal of the day" are the mantras recited often by the ever-working slaves of the food pyramid. The same people are often quick to remind you that not eating at least six loaves of bread each day will surely kill you. But there are also different, non-conventional approaches to this problem. One of them is intermittent fasting, which I have been following for the past six months (click here for the latest update). It's based on the idea that the paleolithic man didn't have access to food all the time. Instead, he would go for long periods without food (hunting and gathering), and when food was available (after a succesful kill), he would eat a lot. Feast and famine. In short, the intermittent fasting approach is the complete opposite to common wisdom, which you've undoubtedly been taught ever since you were on an all-milk diet. So who is right – your mother who warned you not to go too long without eating, or those crazy blogger folks who want you to get in touch with your inner cavema Continue reading >>
Intermittent Fasting Shown To Improve Insulin Sensitivity!
The impact an Intermittent Fasting (IF) eating plan can have on health parameters and performance levels has only been inestigated in a limited number of human trials to date. Whilst much more work needs to be done, early results seem to show that IF can significantly improve your insulin sensitivity. Insulin resistance is a widespread problem in the developed world and it is now well established that insulin resistance is a preceding stage to type 2 diabetes. A number of factors are implicated in people developing insulin resistance – diets containing hydrogenated and refined vegetable fats, too much fructose and sugar, and low levels of minerals involved in insulin action like chromium and magnesium have been shown to lower insulin sensitivity. In my opinion, a very obvious factor is the widespread vitamin d deficiency epidemic that we have nowadays. Some theorise that another reason for the insulin resistance problem we face is simply an overabundance of food available to people. The theory goes that, because are genome was likely selected in the Paleolithic era (50,000–10,000 BC), where we had to hunt for food, our metabolisms are designed to work best on a feast-famine cycle where we have to go for longish periods without eating. A group of Danish researchers set out to test whether following a hunter gatherer diet pattern that provided enforced breaks from eating could improve subjects’ insulin sensitivity (1): Eight young men fasted every second day for 20 h, from 10 pm to 6pm the next day, for 15 days. Euglycemic hyperinsulinemic clamps were performed before and after the intervention period to measure insulin sensitivity (this is the best method in existence for testing insulin sensitivity). The results were as follows: • ‘After the 20-h fasting perio Continue reading >>
