Ketosis Fundamentals
What is ketosis? Ketosis is the physiological state where the concentration of ketone bodies in the blood is higher than normal. This is generally agreed to be at beta-hydroxybutyrate (BHB) concentrations greater than 0.5 mM. How to achieve ketosis? Ketosis occurs either as a result of increased fat oxidation, whilst fasting or following a strict ketosis diet plan (ENDOGENOUS ketosis), or after consuming a ketone supplement (EXOGENOUS ketosis). When in a state of ketosis the body can use ketones to provide a fuel for cellular respiration instead of its usual substrates: carbohydrate, fat or protein. Why does ketosis exist? Normally, the body breaks down carbohydrates, fat, and (sometimes) proteins to provide energy. When carbohydrate is consumed in the diet, some is used immediately to maintain blood glucose levels, and the rest is stored. The hormone that signals to cells to store carbohydrate is insulin. The liver stores carbohydrate as glycogen, this is broken down and released between meals to keep blood glucose levels constant. Muscles also store glycogen, when broken down this provides fuel for exercise. Most cells in the body can switch readily between using carbohydrates and fat as fuel. Fuel used depends on substrate availability, on the energy demands of the cell and other neural and hormonal signals. The brain is different as it is dependent on carbohydrates as a fuel source. This is because fats cannot easily cross the blood-brain barrier. The inability to make use of energy within fat poses a problem during periods where there is limited carbohydrate in the diet. If blood glucose levels fall to low, brain function declines. Relatively little energy is stored as carbohydrate (2,000 kCal) compared to fat (150,000 kCal). The body's store of carbohydrates runs Continue reading >>
How To Fix Your Broken Metabolism By Doing The Exact Opposite
We saw last week with the Biggest Loser study that basal metabolism plummets when you lose weight with calorie reduction. As contestants lose weight, they burn a lot less energy – up to 800 calories per day less than before. Some of that is expected, since there is less body tissue to maintain, but nevertheless, these contestants burn far less than expected even taking this into account. Even 6 years later, their basal metabolic rate (BMR) remains depressed, as do the contestants themselves. The story got a lot of coverage, but one thing was consistently missing. How to fix it.That’s what I’ll show you today, and it’s the opposite of what most people expect. So, let’s think about this problem in the context of the 2 compartment model of obesity that we have used before. There are two compartments for body energy. We take calories in as food. This gets stored in the short term as glycogen, or long term as body fat. Glycogen is easily converted to energy (calories out), but body fat, not so much. So we can consider the analogous situation where short term energy is stored in a refrigerator and long term in the basement freezer. Insulin’s role is to direct food into the basement freezer. When there is excess food that can’t be kept in the fridge, insulin directs it to the freezer. This is body fat and manufactured in the liver by the process of de novo lipogenesis. What causes insulin levels to be elevated depends partly on the foods we eat, but also by insulin resistance. Fructose, for example, plays a key role in elevating insulin resistance which will, in turn raise insulin levels. Insulin resistance leads to high insulin levels, which leads to higher resistance in a vicious cycle. That is, it can be self sustaining. So during weight loss, if we don’t ad Continue reading >>
Metabolism And Ketosis
Dr. Eades, If the body tends to resort to gluconeogenesis for glucose during a short-term carbohydrate deficit, are those who inconsistently reduce carb intake only messing things up by not effecting full blown ketosis? If the body will still prefer glucose as main energy source unless forced otherwise for at least a few days, is it absolutely necessary to completely transform metabolism for minimal muscle loss? Also, if alcohol is broken down into ketones and acetaldehyde, technically couldn’t you continue to drink during your diet or would the resulting gluconeogenesis inhibition from alcohol lead to blood glucose problems on top of the ketotic metabolism? Would your liver ever just be overwhelmed by all that action? I’m still in high school so hypothetical, of course haha… Sorry, lots of questions but I’m always so curious. Thank you so much for taking the time to inform the public. You’re my hero! P.S. Random question…what’s the difference between beta and gamma hydroxybutyric acids? It’s crazy how simple orientation can be the difference between a ketone and date rape drug…biochem is so cool! P.P.S. You should definitely post the details of that inner mitochondrial membrane transport. I’m curious how much energy expenditure we’re talkin there.. Keep doin your thing! Your Fan, Trey No, I don’t think people are messing up if they don’t get into full-blown ketosis. For short term low-carb dieting, the body turns to glycogen. Gluconeogenesis kicks in fairly quickly, though, and uses dietary protein – assuming there is plenty – before turning to muscle tissue for glucose substrate. And you have the Cori cycle kicking in and all sorts of things to spare muscle, so I wouldn’t worry about it. And you can continue to drink while low-carbing. Continue reading >>
Ketogenic Diets And Physical Performance
Abstract Impaired physical performance is a common but not obligate result of a low carbohydrate diet. Lessons from traditional Inuit culture indicate that time for adaptation, optimized sodium and potassium nutriture, and constraint of protein to 15–25 % of daily energy expenditure allow unimpaired endurance performance despite nutritional ketosis. Introduction In the opinion of most physicians and nutrition scientists, carbohydrate must constitute a major component of one's daily energy intake if optimum physical performance is to be maintained [1]. This consensus view is based upon a long list of published studies performed over the last century that links muscle glycogen stores to high intensity exercise. It has also been reinforced by the clinical experience of many physicians, whose patients following low carbohydrate formula or food diets frequently complain of lightheadedness, weakness, and ease of fatigue. During the time that this consensus view of the necessity of carbohydrate for vigorous exercise was forming, the last pure hunting cultures among the peoples of North America finally lost out in competition with expanding European cultural influences. Between 1850 and 1930, the routine consumption of carbohydrates spread north from the U.S. Plains States through central Canada, where the indigenous peoples had heretofore made at most seasonal use of this nutrient class. However the last of these groups to practice their traditional diet, the Inuit people of the Canadian and Alaskan Arctic regions, were luckily observed by modern scientists before their traditional dietary practices were substantially altered. The reports of these early scientists imply that the Inuit people were physically unhampered despite consuming a diet that was essentially free of ide Continue reading >>
What Is Ketosis?
"Ketosis" is a word you'll probably see when you're looking for information on diabetes or weight loss. Is it a good thing or a bad thing? That depends. Ketosis is a normal metabolic process, something your body does to keep working. When it doesn't have enough carbohydrates from food for your cells to burn for energy, it burns fat instead. As part of this process, it makes ketones. If you're healthy and eating a balanced diet, your body controls how much fat it burns, and you don't normally make or use ketones. But when you cut way back on your calories or carbs, your body will switch to ketosis for energy. It can also happen after exercising for a long time and during pregnancy. For people with uncontrolled diabetes, ketosis is a sign of not using enough insulin. Ketosis can become dangerous when ketones build up. High levels lead to dehydration and change the chemical balance of your blood. Ketosis is a popular weight loss strategy. Low-carb eating plans include the first part of the Atkins diet and the Paleo diet, which stress proteins for fueling your body. In addition to helping you burn fat, ketosis can make you feel less hungry. It also helps you maintain muscle. For healthy people who don't have diabetes and aren't pregnant, ketosis usually kicks in after 3 or 4 days of eating less than 50 grams of carbohydrates per day. That's about 3 slices of bread, a cup of low-fat fruit yogurt, or two small bananas. You can start ketosis by fasting, too. Doctors may put children who have epilepsy on a ketogenic diet, a special high-fat, very low-carb and protein plan, because it might help prevent seizures. Adults with epilepsy sometimes eat modified Atkins diets. Some research suggests that ketogenic diets might help lower your risk of heart disease. Other studies show sp Continue reading >>
Metabolic Damage And Keto Adaptation – Why And How.
I have been getting questions about how to keto adapt, and how long does keto adaption take etc. and does keeping calories up while keto dieting, does this reduce metabolic damage or adaptation even if your carbs are very low? So what this question is kind of centering on is the concept about metabolic damage and adaptation. My take is that your body becomes very efficient at burning calories when you drive your calories lower and lower and do more and more steady state cardio. I’m not talking about 1 or 2 – 45 min cardio sessions a week, I’m talking more about one or two hours of cardio per day. So this is a high amount of cardio and very low calories. Essentially what you’re doing is you’re just kind of metabolically shocking your system and your body responds by becoming a lot more efficient. Now these mechanisms of efficiency are starting to get studied in the scientific world but that’s basically kind of what we are talking about. Right now there isn’t much evidence, but they do believe something is there. The basis of these adaptations is definitely present. So how this does relate specifically to a ketogenic diet, and you know because your carbs are really low, can you still keep your calories high so you don’t get these metabolic adaptations. And the answer is yes. So what about ketosis? Let’s Get Scientific for a Moment This is a really important key to remember, ketosis is not weight loss, instead ketosis is actually a metabolic state when fat is being burned as your primary fuel source and then ketones are being produced. Ketones are by products of fat metabolism. Fat is getting oxidized at a very high rate, which results in ketone production and then you can measure ketones in either your urine (not recommended as I discuss here in my TOP K Continue reading >>
Ketosis For Metabolism Control
We know that simply counting calories doesn’t work for weight loss. The threadbare ideas of “calories in versus calories out” and “just eat less and exercise more” are outdated concepts, and not effective long-term. However we do know that the quality of your diet has a tremendous impact on your hormones, satiety, and body composition. In this article, we cover how ketosis for metabolic control wins out over other ways to try and lose fat. How Ketosis Changes Metabolism Let’s do a very quick overview of metabolism in the context of ketosis: When the average person eats, their body breaks down carbohydrates into glucose to be used as energy for all functions of the body. In this case, carbohydrates provide the main fuel source for the body. But when someone is in ketosis, either from eating a ketogenic diet or from fasting, their body is instead breaking down fats into ketone bodies for energy. These ketone bodies are then used to provide the body with a constant source of energy instead of carbs. Being in ketosis allows you to literally shift your metabolism. Now, let’s look at some of the powerful ways ketosis can be used for maintaining a healthy metabolism: Calorie Restriction Versus Ketosis As we prefaced above, simply reducing calories to lose weight is not effective. We know this based on research from people like Gary Taubes. And that’s just part of the story: it can actually be harmful to your metabolism and lower metabolic rate (the amount of calories the body burns per day) — just look at the long-term results from past winners of the Biggest Loser. After forcing the body into caloric reduction, the contestants’ metabolisms dropped, leading to weight loss plateaus and weight regain. In contrast, research has also shown that when we fast, th Continue reading >>
The Ketogenic Diet's Effect On Cortisol Metabolism
(Related post: Red Light, Green Light: responses to cortisol levels in keto vs. longevity research) One of the myths surrounding ketogenic diets comes from misunderstanding the role of cortisol — the "stress hormone". In a previous post, we addressed one of the arguments behind this myth: the idea that to activate gluconeogenesis (to make glucose out of protein), extra cortisol must be recruited. That is just factually incorrect, as we showed in the post. The other argument, which we address here, is more complex. Like the previous cortisol myth, it involves a faulty chain of reasoning. Here are the steps: Ketogenic diets may raise certain measures of cortisol. Chronically elevated cortisol is correlated with metabolic sydrome, and therefore higher cortisol measures may indicate the onset of metabolic syndrome. Therefore, ketogenic diets could cause metabolic syndrome. Metabolic syndrome is a terrible and prevalent problem today. It is that cluster of symptoms most strongly identified with diabetes — excess abdominal fat, high blood sugar, and a particular cholesterol profile — but also correlated with other life-threatening conditions such as heart disease and cancer. In this post, we're going to explain some of the specifics of cortisol metabolism. We'll show how this argument is vague, and how clarifying it leads to the opposite conclusion. The confusion may all stem from misunderstanding one important fact: different measures of cortisol are not equivalent. First, though, there is an important reason why the argument doesn't make sense. We already know that a ketogenic diet effectively treats metabolic syndrome. As we will describe below, it turns out that certain cortisol patterns are strongly linked to metabolic syndrome, and might even be a cause of metabol Continue reading >>
- Low-Carb and Ketogenic Diets for Dogs with Diabetes
- Effect of Probiotics on Glucose and Lipid Metabolism in Type 2 Diabetes Mellitus: A Meta-Analysis of 12 Randomized Controlled Trials
- The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus
Nutritional Ketosis Affects Metabolism And Behavior In Sprague-dawley Rats In Both Control And Chronic Stress Environments
1Applied Neuroscience Branch, Warfighter Interface Division, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, OH, USA 2Research Associateship Program, National Research Council, National Academies of Science, Washington DC, USA 3Infoscitex, Inc., Dayton, OH, USA Nutritional ketosis may enhance cerebral energy metabolism and has received increased interest as a way to improve or preserve performance and resilience. Most studies to date have focused on metabolic or neurological disorders while anecdotal evidence suggests that ketosis may enhance performance in the absence of underlying dysfunction. Moreover, decreased availability of glucose in the brain following stressful events is associated with impaired cognition, suggesting the need for more efficient energy sources. We tested the hypotheses that ketosis induced by endogenous or exogenous ketones could: (a) augment cognitive outcomes in healthy subjects; and (b) prevent stress-induced detriments in cognitive parameters. Adult, male, Sprague Dawley rats were used to investigate metabolic and behavioral outcomes in 3 dietary conditions: ketogenic (KD), ketone supplemented (KS), or NIH-31 control diet in both control or chronic stress conditions. Acute administration of exogenous ketones resulted in reduction in blood glucose and sustained ketosis. Chronic experiments showed that in control conditions, only KD resulted in pronounced metabolic alterations and improved performance in the novel object recognition test. The hypothalamic-pituitary-adrenal (HPA) axis response revealed that KD-fed rats maintained peripheral ketosis despite increases in glucose whereas no diet effects were observed in ACTH or CORT levels. Both KD and KS-fed rats decreased escape latencies on the third day of water maze, Continue reading >>
The Fat-fueled Brain: Unnatural Or Advantageous?
Disclaimer: First things first. Please note that I am in no way endorsing nutritional ketosis as a supplement to, or a replacement for medication. As you’ll see below, data exploring the potential neuroprotective effects of ketosis are still scarce, and we don’t yet know the side effects of a long-term ketogenic diet. This post talks about the SCIENCE behind ketosis, and is not meant in any way as medical advice. The ketogenic diet is a nutritionist’s nightmare. High in saturated fat and VERY low in carbohydrates, “keto” is adopted by a growing population to paradoxically promote weight loss and mental well-being. Drinking coffee with butter? Eating a block of cream cheese? Little to no fruit? To the uninitiated, keto defies all common sense, inviting skeptics to wave it off as an unnatural “bacon-and-steak” fad diet. Yet versions of the ketogenic diet have been used to successfully treat drug-resistant epilepsy in children since the 1920s – potentially even back in the biblical ages. Emerging evidence from animal models and clinical trials suggest keto may be therapeutically used in many other neurological disorders, including head ache, neurodegenerative diseases, sleep disorders, bipolar disorder, autism and brain cancer. With no apparent side effects. Sound too good to be true? I feel ya! Where are these neuroprotective effects coming from? What’s going on in the brain on a ketogenic diet? Ketosis in a nutshell In essence, a ketogenic diet mimics starvation, allowing the body to go into a metabolic state called ketosis (key-tow-sis). Normally, human bodies are sugar-driven machines: ingested carbohydrates are broken down into glucose, which is mainly transported and used as energy or stored as glycogen in liver and muscle tissue. When deprived of d Continue reading >>
Can You Really Fix Your Metabolism With The Keto Diet?
The new best-selling book “The Keto Reset Diet” says it can fix a sluggish metabolism and train your body to be a fat-burning machine. Experts are skeptical. It isn’t just you. Dieting is an endless pursuit for many Americans. Around 45 million Americans go on a diet each year. And the weight eventually comes back for 33 to 66 percent of people who’ve dieted. In the New York Times best-seller “The Keto Reset Diet: Reboot Your Metabolism in 21 Days and Burn Fat Forever,” author and keto diet enthusiast Mark Sisson writes that “yo-yo dieting is severely destructive to your metabolism.” He claims that following a low-carb, high-fat diet will help “turn you into a ‘fat-burning beast’ and stay this way for the rest of your life.” The book explains that the three-week keto reset diet does this by reprograming your genes into a state of “metabolic efficiency” — which he considers burning fat, rather than being “dependent upon regular high-carbohydrate meals to sustain your energy, mood, or cognitive focus.” Critics say the science doesn’t support these claims. Does yo-yo dieting really affect your metabolism? A person’s resting metabolic rate (RMR) is largely based on their weight, but factors like age and genetics also play a role. When someone significantly restricts calories to lose weight, their body can also enter starvation mode. Their metabolism slows down considerably to conserve energy. Extremely low-calorie diets make it easier to regain weight after a diet is over. If someone with a slowed metabolism hits their target weight and celebrates by eating the same amount of daily calories a person with a typical RMR and of their same weight and age would eat, they could gain weight rapidly. Case in point: contestants from the TV show Continue reading >>
Metabolic Effects Of The Very-low-carbohydrate Diets: Misunderstood "villains" Of Human Metabolism
Go to: The Ketone Bodies are an Important Fuel The hormonal changes associated with a low carbohydrate diet include a reduction in the circulating levels of insulin along with increased levels of glucagon. This activates phosphoenolpyruvate carboxykinase, fructose 1,6-biphosphatase, and glucose 6-phosphatase and also inhibits pyruvate kinase, 6-phosphofructo-1-kinase, and glucokinase. These changes indeed favor gluconeogenesis. However, the body limits glucose utilization to reduce the need for gluconeogenesis. In the liver in the well-fed state, acetyl CoA formed during the β-oxidation of fatty acids is oxidized to CO2 and H2O in the citric acid cycle. However, when the rate of mobilization of fatty acids from adipose tissue is accelerated, as, for example, during very low carbohydrate intake, the liver converts acetyl CoA into ketone bodies: Acetoacetate and 3-hydroxybutyrate. The liver cannot utilize ketone bodies because it lacks the mitochondrial enzyme succinyl CoA:3-ketoacid CoA transferase required for activation of acetoacetate to acetoacetyl CoA [3]. Therefore, ketone bodies flow from the liver to extra-hepatic tissues (e.g., brain) for use as a fuel; this spares glucose metabolism via a mechanism similar to the sparing of glucose by oxidation of fatty acids as an alternative fuel. Indeed, the use of ketone bodies replaces most of the glucose required by the brain. Not all amino acid carbon will yield glucose; on average, 1.6 g of amino acids is required to synthesize 1 g of glucose [4]. Thus, to keep the brain supplied with glucose at rate of 110 to 120 g/day, the breakdown of 160 to 200 g of protein (close to 1 kg of muscle tissue) would be required. This is clearly undesirable, and the body limits glucose utilization to reduce the need for gluconeogenesis Continue reading >>
In Depth Look At Ketogenic Diets And Ketosis
What exactly is Ketosis? The metabolic state of ketosis simply means that the quantity of ketone bodies in the blood have reached higher-than-normal levels. When the body is in a ketogenic state, this means that lipid energy metabolism is intact. The body will start breaking down your own body fat to fuel the body's normal, everyday functions. What's So Great About Being In Ketosis? Establishing this metabolic state of ketosis even for a short period of time has many outstanding benefits. Benefit 1 The main benefit of ketosis is that it increases the body's ability to utilize fats for fuel, which gets very lazy on a high-carbohydrate diet. When on high-carbohydrate diets, the body can usually expect an energy source to keep entering the body. But in the state of ketosis, the body has to become efficient at mobilizing fats as energy. Benefit 2 Ketosis has a protein-sparing effect, assuming that you are consuming adequate quantities of protein and calories—0.7 grams per pound of body weight per day—in the first place.[1] Once in ketosis, the body actually prefers ketones to glucose. Since the body has copious quantities of fat, this means there is no need to oxidize protein to generate glucose through gluconeogenesis. Benefit 3 Another benefit has to do with the low levels of insulin in the body, which causes greater lipolysis and free-glycerol release compared to a normal diet when insulin is around 80-120. Insulin has a lipolysis-blocking effect, which can inhibit the use of fatty acids as energy. Also, when insulin is brought to low levels, beneficial hormones are released in the body, such as growth hormone and other powerful growth factors. Benefit 4 Another small but very important benefit of the ketogenic diet is that when in the state of ketosis, ketones, alon Continue reading >>
Burn Fat With A Cyclical Ketogenic Diet
The Cyclical Ketogenic Diet What is a cyclical ketogenic diet and how does it help one burn fat? By the way, what even constitutes an optimal physique? This is different based on each individual’s unique genetic potential but researchers would agree that we should have a moderate to thin structure and good muscular development. While many have sought after a thin physique, the mantra of the 21st century is that strong is the new thin! We want to have a good body fat percentage (6-15% for men and 15-30% for women) and have developed well-toned musculature. This article discusses how to build muscle and burn fat with a cyclical ketogenic diet Ketogenic Diet and Fat Metabolism: A ketogenic diet is a very low carbohydrate, moderate protein and high fat based nutrition plan. A ketogenic diet trains the bodies metabolism to run off of fatty acids or ketone bodies. This nutrition plan has been shown to improve insulin sensitivity and reduce inflammation. This leads to improved muscle development and fat metabolism (1, 2). The ketogenic diet is built around good fats such as grass-fed butter, coconut products, avocados, nuts/seeds, pasture-raised animal products and extra-virgin olive oil. This diet should also focus on low-carbohydrate fruits, vegetables and herbs as staple components. The fat levels will be between 60-80% of calorie intake. How Ketones Are Formed? The body has two major energy sources, it burns glucose or ketone bodies. The majority of people burn glucose primarily because they are constantly supplying a steady form of sugar, starches and proteins that can be turned into blood sugar. When one either fasts or goes on a low-carb, moderate protein and high fat diet they switch their energy source to fat. In particular, the fatty acids are broken down into keto Continue reading >>
Metabolic Pathways: How The Body Uses Energy
Metabolic pathways in the body determine how we utilize the macronutrients (carbohydrates, proteins and fats) we eat, and ultimately what happens to the fuels that come from each macronutrient. It all depends on when the last meal was finished. If the body is in a "fasting or starvation" mode, energy pathways will behave differently than when food is available. Food is available! The macronutrients (carbohydrate, fats and protein) on your plate are broken down in separate metabolic pathways: Carbohydrates are broken down into glucose by various enzymes. Some are burned for immediate energy, but overall the level of glucose in the blood stream rises, which triggers an insulin release by the pancreas. The insulin acts to push glucose into the cells to be made into ATP, stored as glycogen or when in excess amounts, stored as fat droplets called triglycerides in the fat cells (adipose tissue). Fats are digested in the small intestine, and then packaged into lipoproteins for various functions (ever heard of LDL and HDL? ) Excess fat calories often end up as fat droplets in fat cells. When fats are used as an energy source, they are broken down in cellular mitochondria through a process called beta-oxidation. Proteins are broken down into individual amino acids and used in body cells to form new proteins or to join the amino acid pool, a sort of "cache" for these molecules. Amino acids that are in excess of the body's needs are converted by liver enzymes into keto acids and urea. Keto acids may be used as sources of energy, converted into glucose, or stored as fat. Urea is excreted from everyone’s body in sweat and urine. Body is "Fasting" Carbohydrate, fats and protein are metabolized in separate processes into a common product called acetyl-CoA. Acetyl-CoA is a major meta Continue reading >>
