Ketosis In An Evolutionary Context
Humans are unique in their remarkable ability to enter ketosis. They’re also situated near the top of the food chain. Coincidence? During starvation, humans rapidly enter ketosis; they do this better than king penguins, and bears don’t do it at all. Starvation ketosis Humans maintain a high level of functionality during starvation. We can still hunt & plan; some would even argue it’s a more finely tuned state, cognitively. And that’s important, because if we became progressively weaker and slower, chances of acquiring food would rapidly decline. Perhaps this is why fasting bears just sleep most of the time: no ketones = no bueno..? Animals with a low brain/carcass weight ratio (ie, small brain) don’t need it. Babies and children have a higher brain/carcass weight ratio, so they develop ketosis more rapidly than adults. Is this a harmful process? No, more likely an evolutionary adaptation which supports the brain. The brain of newborn babies consumes a huge amount of total daily energy, and nearly half comes from ketones. A week or so later, even after the carbohydrate content of breast milk increases, they still don’t get “kicked out of ketosis” (Bourneres et al., 1986). If this were a harmful state, why would Nature have done this? …and all those anecdotes, like babies learn at incredibly rapid rates… coincidence? Maybe they’re myths. Maybe not. Ketosis in the animal kingdom Imagine a hibernating bear: huge adipose tissue but small brain fuel requirement relative to body size and total energy expenditure. No ketosis, because brain accounts for less than 5% of total metabolism. In adult humans, this is around 19-23%, and babies are much higher (eg, Cahill and Veech, 2003 & Hayes et al., 2012). For the rest of this article and more, head over to Pat Continue reading >>
The Truth About Ketosis & Low-carb Diets, Backed By Science
A lot of people are confused by the term “ketosis.” You may read that it is a “dangerous state” for the body, and it does sound abnormal to be “in ketosis.” But ketosis merely means that our bodies are using fat for energy. Ketones (also called ketone bodies) are molecules generated during fat metabolism, whether from the fat in the almonds you just ate or fat you were carrying around your middle. When our bodies are breaking down fat for energy, most of it gets converted to energy, but ketones are also produced as part of the process. When people eat less carbohydrates, their bodies turn to fat for energy, so it makes sense that more ketones are generated. Some of those ketones (acetoacetate and ß-hydroxybutyrate) are used for energy; the heart muscle and kidneys, for example, prefer ketones to glucose. Most cells, including the brain cells, are able to use ketones for at least part of their energy. Is ketosis a bad thing? There is an assumption that if a body is burning a lot of fat for energy, it must not be getting “enough” glucose. However, there is no indication, from studying people on reduced carbohydrate diets, that this is the case (though there is usually a short period of adjustment, less than a week, in most cases). It takes about 72 hours to burn up all of the reserve glycogen (sugar loads). Although it’s true that our bodies can’t break fat down directly into glucose (though, interestingly, they easily use glucose to make fat), our bodies can convert some of the protein we eat into glucose. Indeed, this works well for people who don’t tolerate a lot of sugar, because this conversion happens slowly so it doesn’t spike blood glucose. What is the danger of ketosis? It is important that if you are following a ketogenic nutritional pro Continue reading >>
Ketosis, Ketones, And How It All Works
Ketosis is a process that the body does on an everyday basis, regardless of the number of carbs you eat. Your body adapts to what is put in it, processing different types of nutrients into the fuels that it needs. Proteins, fats, and carbs can all be processed for use. Eating a low carb, high fat diet just ramps up this process, which is a normal and safe chemical reaction. When you eat carbohydrate based foods or excess amounts of protein, your body will break this down into sugar – known as glucose. Why? Glucose is needed in the creation of ATP (an energy molecule), which is a fuel that is needed for the daily activities and maintenance inside our bodies. If you’ve ever used our keto calculator to determine your caloric needs, you will see that your body uses up quite a lot of calories. It’s true, our bodies use up much of the nutrients we intake just to maintain itself on a daily basis. If you eat enough food, there will likely be an excess of glucose that your body doesn’t need. There are two main things that happen to excess glucose if your body doesn’t need it: Glycogenesis. Excess glucose will be converted to glycogen and stored in your liver and muscles. Estimates show that only about half of your daily energy can be stored as glycogen. Lipogenesis. If there’s already enough glycogen in your muscles and liver, any extra glucose will be converted into fats and stored. So, what happens to you once your body has no more glucose or glycogen? Ketosis happens. When your body has no access to food, like when you are sleeping or when you are on a ketogenic diet, the body will burn fat and create molecules called ketones. We can thank our body’s ability to switch metabolic pathways for that. These ketones are created when the body breaks down fats, creating Continue reading >>
Fasting Ketosis And Alcoholic Ketoacidosis
INTRODUCTION Ketoacidosis is the term used for metabolic acidoses associated with an accumulation of ketone bodies. The most common cause of ketoacidosis is diabetic ketoacidosis. Two other causes are fasting ketosis and alcoholic ketoacidosis. Fasting ketosis and alcoholic ketoacidosis will be reviewed here. Issues related to diabetic ketoacidosis are discussed in detail elsewhere. (See "Diabetic ketoacidosis and hyperosmolar hyperglycemic state in adults: Epidemiology and pathogenesis" and "Diabetic ketoacidosis and hyperosmolar hyperglycemic state in adults: Clinical features, evaluation, and diagnosis" and "Diabetic ketoacidosis and hyperosmolar hyperglycemic state in adults: Treatment".) PHYSIOLOGY OF KETONE BODIES There are three major ketone bodies, with the interrelationships shown in the figure (figure 1): Acetoacetic acid is the only true ketoacid. The more dominant acid in patients with ketoacidosis is beta-hydroxybutyric acid, which results from the reduction of acetoacetic acid by NADH. Beta-hydroxybutyric acid is a hydroxyacid, not a true ketoacid. Continue reading >>
Ketosis: What Is Ketosis?
Ketosis is a normal metabolic process. When the body does not have enough glucose for energy, it burns stored fats instead; this results in a build-up of acids called ketones within the body. Some people encourage ketosis by following a diet called the ketogenic or low-carb diet. The aim of the diet is to try and burn unwanted fat by forcing the body to rely on fat for energy, rather than carbohydrates. Ketosis is also commonly observed in patients with diabetes, as the process can occur if the body does not have enough insulin or is not using insulin correctly. Problems associated with extreme levels of ketosis are more likely to develop in patients with type 1 diabetes compared with type 2 diabetes patients. Ketosis occurs when the body does not have sufficient access to its primary fuel source, glucose. Ketosis describes a condition where fat stores are broken down to produce energy, which also produces ketones, a type of acid. As ketone levels rise, the acidity of the blood also increases, leading to ketoacidosis, a serious condition that can prove fatal. People with type 1 diabetes are more likely to develop ketoacidosis, for which emergency medical treatment is required to avoid or treat diabetic coma. Some people follow a ketogenic (low-carb) diet to try to lose weight by forcing the body to burn fat stores. What is ketosis? In normal circumstances, the body's cells use glucose as their primary form of energy. Glucose is typically derived from dietary carbohydrates, including: sugar - such as fruits and milk or yogurt starchy foods - such as bread and pasta The body breaks these down into simple sugars. Glucose can either be used to fuel the body or be stored in the liver and muscles as glycogen. If there is not enough glucose available to meet energy demands, th Continue reading >>
What Is Starvation Ketosis?
Starvation ketosis is a metabolic state in humans and many animals in which the body breaks down fat and produces acids known as ketones, then uses these as a primary energy source. The “starvation” part of the name owes to the fact that, in most cases, people only use ketones for energy when they aren’t getting adequate glucose from food. The body typically converts carbohydrates to glucose as a main source of energy, but once the liver has used all of its stored glucose it begins to metabolize fatty acids, forming ketone bodies. Malnutrition and fasting are two of the most common causes, but it can also be the result of conditions like diabetes, alcoholism, and a low carbohydrate diet. People sometimes intentionally trigger this state as a means of burning fat to lose weight, but whether this practice is safe or even advisable is widely disputed in the medical community. Ketones are capable of supplying energy to the body, but an abnormally high level can cause a number of problems, including organ damage, coma, and even death. Understanding Ketones The liver typically makes ketones in response to some sort of energy crisis in the body. People generally get the majority of their energy by synthesizing glucose, which is a sugar molecule found in carbohydrates like bread and grain products. When people aren’t getting enough glucose, the liver begins creating ketones that the body uses in combination with any fat stores it has on hand. Ketones in many ways prevent the body from robbing muscles of their core proteins. Starvation ketosis happens when these become the body’s primary source of energy. The condition can usually be identified by looking for excesses. The body gets rid of unneeded supplies by spilling them out through exhalations, urine, and sweat. Wh Continue reading >>
“starvation Mode” And Muscle Wasting Myth On A Low Carbohydrate Diet
Another one of the fallacies that seems to pervade is that a ketogenic diet is the same as being in starvation – whereby the body significantly reduces it’s metabolism and starts tapping into the muscles for energy. This is completely bogus and you’d be best off just ignoring the idea altogether. In light of restricted carbohydrates through either keto or starvation the body will focus on maintaining glucose homeostasis, ie constant blood-glucose level. It’s highest priority is to provide sufficient energy to the brain and other critical functions, and can do so with a mix of glucose and ketone bodies. The only real common ground is that ketone production is elevated in both a keto diet and in starvation due to reduced carbohydrate intake. Conflating keto with starvation is guilt by association – eg falling asleep makes you unconscious; being punched out also renders you unconscious and can cause serious injury; therefore falling asleep is dangerous like being punched out. Starvation is just that – severe restriction of calories over a long period, and “starvation mode” is what anti-low-carb people tend to call it as a scare tactic. After a few days of complete fasting the metabolic rate only drops 5-10% – sometimes increases – and even on an intake of half the amount of energy you’d normally consume for maintenance, you would be fine for months without too much of a drop. If you have a significant amount of fat to lose then your metabolism will barely drop at all, even on severe restriction your extra adipose stores will make up any energy requirements you have. A ketogenic diet stabilises glucose and maintains very low levels of circulating insulin, so access to liberating energy from your adipose stores is unhampered. A ketogenic diet is extreme Continue reading >>
- The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus
- The interpretation and effect of a low-carbohydrate diet in the management of type 2 diabetes: a systematic review and meta-analysis of randomised controlled trials
- Wasting Money on Diabetes Education That Fails to Teach the Right Things
What Is Ketosis, And Is It Healthy?
Ketosis is a natural metabolic state. It involves the body producing ketone bodies out of fat, and using them for energy instead of carbs. You can get into ketosis by following a very low-carb, high-fat ketogenic diet (1). In addition to fast weight loss, ketosis may have several health benefits, such as reduced seizures in epileptic children (2). Ketosis is quite complex, but this article explains what it is and how it can benefit you. Ketosis is a metabolic state in which fat provides most of the fuel for the body. It occurs when there is limited access to glucose (blood sugar), which is the preferred fuel source for many cells in the body. Ketosis is most often associated with ketogenic and very low-carb diets. It also happens during pregnancy, infancy, fasting and starvation (3, 4, 5, 6). To go into ketosis, people generally need to eat fewer than 50 grams of carbs per day and sometimes as little as 20 grams per day. This requires removing certain food items from your diet, such as grains, candy and sugary soft drinks. You also have to cut back on legumes, potatoes and fruit. When eating a very low-carb diet, levels of the hormone insulin go down and fatty acids are released from body fat stores in large amounts. Many of these fatty acids are transferred to the liver, where they are oxidized and turned into ketones (or ketone bodies). These molecules can provide energy for the body. Unlike fatty acids, ketones can cross the blood-brain barrier and provide energy for the brain in the absence of glucose. Ketosis is a metabolic state where ketones become the main sources of energy for the body and brain. This happens when carb intake and insulin levels are very low. It's a common misunderstanding that the brain doesn't function without dietary carbs. It's true that glu Continue reading >>
Ketoacidosis
GENERAL ketoacidosis is a high anion gap metabolic acidosis due to an excessive blood concentration of ketone bodies (keto-anions). ketone bodies (acetoacetate, beta-hydroxybutyrate, acetone) are released into the blood from the liver when hepatic lipid metabolism has changed to a state of increased ketogenesis. a relative or absolute insulin deficiency is present in all cases. CAUSES The three major types of ketosis are: (i) Starvation ketosis (ii) Alcoholic ketoacidosis (iii) Diabetic ketoacidosis STARVATION KETOSIS when hepatic glycogen stores are exhausted (eg after 12-24 hours of total fasting), the liver produces ketones to provide an energy substrate for peripheral tissues. ketoacidosis can appear after an overnight fast but it typically requires 3 to 14 days of starvation to reach maximal severity. typical keto-anion levels are only 1 to 2 mmol/l and this will usually not alter the anion gap. the acidosis even with quite prolonged fasting is only ever of mild to moderate severity with keto-anion levels up to a maximum of 3 to 5 mmol/l and plasma pH down to 7.3. ketone bodies also stimulate some insulin release from the islets. patients are usually not diabetic. ALCOHOLIC KETOSIS Presentation a chronic alcoholic who has a binge, then stops drinking and has little or no oral food intake for a few days (ethanol and fasting) volume depletion is common and this can result in increased levels of counter regulatory hormones (eg glucagon) levels of free fatty acids (FFA) can be high (eg up to 3.5mM) providing plenty of substrate for the altered hepatic lipid metabolism to produce plenty of ketoanions GI symptoms are common (eg nausea, vomiting, abdominal pain, haematemesis, melaena) acidaemia may be severe (eg pH down to 7.0) plasma glucose may be depressed or normal or 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 >>
What Is The Difference Between Ketogenic Diet And Starvation?
I really must track down how the unscientific drivel that the ketogenic diet is some sort of a starvation response got started. The only link between starvation and the ketogenic diet is the production of ketones in the body. I know certain Quora gurus posit such crap repeatedly but it’s not true. Ketones as a natural process in the body The body produces ketones naturally. It’s likely a protective mechanism due to the evolutionary instability of the food supply. Most of the time ketone levels are quite low. However, anytime the food supply gets interrupted, even short times like at night during sleep, the body starts to produce ketones. Ketones and fat metabolism Ketones are made in the liver from fat. One of the reasons people measure ketone levels in the body is that they are a marker for increased fat utilization in the body. There are two fuel partitioning schemes in the human body. The body can utilize glucose and glycogen or the body can utilize fats (dietary and body) and ketones. There are some overlaps in the utilization of these schemes but when foods that are easily broken down into glucose are withdrawn the body will start to burn fats and ketones as sources of energy. Ketones and starvation The similarity between starvation and the ketogenic diet is that both involve higher levels of circulating ketones in the body. This makes sense since in both situations foods that are easily broken down into glucose have been withdrawn. In both situations, levels of blood glucose and glycogen stores are lower and the body must fuel with other substances. Some tissues in the body are perfectly happy (and in many ways) prefer utilizing fats as fuels. However, some tissues need levels of glucose. These tissues when faced with lower glucose intake in the diet must rely Continue reading >>
The Biggest Loser Fail And That Ketogenic Study Success
This week, splashed all over the New York Times, was an article about a paper written by Kevin Hall, a senior researcher at the National Institutes of Health. It was published in Obesity and titled “Persistent metabolic adaptation 6 years after ‘The Biggest Loser competition“. This generated a lot of hand-wringing about the futility of weight loss. NYT: After ‘The Biggest Loser,’ Their Bodies Fought to Regain Weight The study, along with another study presented by Kevin Hall seemed to generate more anxiety about the insulin hypothesis being dead. Of course, both these studies fit in perfectly with the hormonal view of obesity and reinforces once again the futility of following the Caloric Reduction as Primary approach. You could review my 50ish part series on Hormonal Obesity if you want a more in-depth view. So, let’s dive in an explain the findings of both of Dr. Hall’s excellent papers. His conclusions, well, let’s just say I don’t agree with them. The studies, though, were very well done. The Biggest Loser Let’s start with the first paper about the Biggest Loser. Essentially, what it did was follow 14 of the 16 Biggest Loser contestants. At the end of the show, they had all lost significant amounts of weight following a Eat Less, Move More approach. Contestants eat about 1000 – 1200 calories per day and exercise like mad people. What the study showed is that basal metabolism drops like a piano out of the Empire State building. It plummets. They are burning about 800 calories less per day than previously. The new paper shows that this metabolic rate does not recover even 6 years later. In other words, if you reduce your ‘Calories In’, your ‘Calories Out’ will automatically drop. This makes sense. If your body normally eats 2000 calories Continue reading >>
Starvation Ketoacidosis As A Cause Of Unexplained Metabolic Acidosis In The Perioperative Period
Go to: Abstract Patient: Female, 24 Final Diagnosis: Starvation ketoacidosis Symptoms: None Medication: — Clinical Procedure: Lumbar laminectomy Specialty: Orthopedics and Traumatology Besides providing anesthesia for surgery, the anesthesiologist’s role is to optimize the patient for surgery and for post-surgical recovery. This involves timely identification and treatment of medical comorbidities and abnormal laboratory values that could complicate the patient’s perioperative course. There are several potential causes of anion and non-anion gap metabolic acidosis in surgical patients, most of which could profoundly affect a patient’s surgical outcome. Thus, the presence of an acute acid-base disturbance requires a thorough workup, the results of which will influence the patient’s anesthetic management. An otherwise-healthy 24-year-old female presented for elective spine surgery and was found to have metabolic acidosis, hypotension, and polyuria intraoperatively. Common causes of acute metabolic acidosis were investigated and systematically ruled out, including lactic acidosis, diabetic ketoacidosis, drug-induced ketoacidosis, ingestion of toxic alcohols (e.g., methanol, ethylene glycol), uremia, and acute renal failure. Laboratory workup was remarkable only for elevated serum and urinary ketone levels, believed to be secondary to starvation ketoacidosis. Due to the patient’s unexplained acid-base disturbance, she was kept intubated postoperatively to allow for further workup and management. Starvation ketoacidosis is not widely recognized as a perioperative entity, and it is not well described in the medical literature. Lack of anesthesiologist awareness about this disorder may complicate the differential diagnosis for acute intraoperative metabolic acidosi Continue reading >>
Why Dka & Nutritional Ketosis Are Not The Same
There’s a very common misconception and general misunderstanding around ketones. Specifically, the misunderstandings lie in the areas of: ketones that are produced in low-carb diets of generally less than 50 grams of carbs per day, which is low enough to put a person in a state of “nutritional ketosis” ketones that are produced when a diabetic is in a state of “diabetic ketoacidosis” (DKA) and lastly, there are “starvation ketones” and “illness-induced ketones” The fact is they are very different. DKA is a dangerous state of ketosis that can easily land a diabetic in the hospital and is life-threatening. Meanwhile, “nutritional ketosis” is the result of a nutritional approach that both non-diabetics and diabetics can safely achieve through low-carb nutrition. Diabetic Ketoacidosis vs. Nutritional Ketosis Ryan Attar (soon to be Ryan Attar, ND) helps explain the science and actual human physiology behind these different types of ketone production. Ryan is currently studying to become a Doctor of Naturopathic Medicine in Connecticut and also pursuing a Masters Degree in Human Nutrition. He has interned under the supervision of the very well-known diabetes doc, Dr. Bernstein. Ryan explains: Diabetic Ketoacidosis: “Diabetic Ketoacidosis (DKA), is a very dangerous state where an individual with uncontrolled diabetes is effectively starving due to lack of insulin. Insulin brings glucose into our cells and without it the body switches to ketones. Our brain can function off either glucose or fat and ketones. Ketones are a breakdown of fat and amino acids that can travel through the blood to various tissues to be utilized for fuel.” “In normal individuals, or those with well controlled diabetes, insulin acts to cancel the feedback loop and slow and sto 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 >>
