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Where Are Ketone Bodies Broken Down?

Everything You Need To Know About Ketones

Everything You Need To Know About Ketones

Ketone is an organic compound that the body produces when fats are broken down for energy. People with diabetes may not be able to regulate the level of ketones in their blood, so ketone testing is an essential part of managing their condition. There are three types of ketone, which are collectively known as ketone bodies, or ketones. In this article, we explain when to check for ketones, the types of tests available, and how to understand the results. Contents of this article: What are ketones? The body uses a range of nutrients for energy, including carbohydrates, fats, and proteins. It will use carbohydrates first, but if none are available, the body will burn fat for energy. When this happens, ketones are produced. Ketones have gained attention in recent years due to the popularity of ketogenic diets, in which people eat a low carbohydrate diet so that their body will burn fat instead of carbohydrates. There is currently a lack of clear evidence on the benefits of this diet, and there may be some risks, such as high acidity in the blood and loss of muscle. Typically, carbohydrates are broken down into different nutrients, including blood sugar (glucose), by an enzyme called amylase that occurs naturally in the body. Insulin then transports the sugar to cells to be used for energy. A person with diabetes does not produce enough insulin to transport the blood sugar, or the cells in their body may not accept it properly, which stops the body from using the blood sugar for energy. When sugar can't be used by the cells for energy, the body will start to break down fats for energy instead. Types of ketone and DKA Three types of ketones are always present in the blood: acetoacetate (AcAc) 3-β-hydroxybutyrate (3HB) acetone The levels of each of these ketone bodies will var Continue reading >>

“ketone Bodies” A Trendy Word

“ketone Bodies” A Trendy Word

Health Writer Ketosis is a normal process where excessive ketone bodies formed, a crucial organic compound – acetoacetate, when human body is starved of carbohydrates for energy requirements. Plan B in the body under such strained situations would be to use fatty acids stored in the body as triglycerides to burn its own fat for fuel, for energy requirements in the liver, heart and kidneys, due to the restriction of energy from carbohydrates. The process of ketones production in humans is called ketogenesis. In the brain, they are a vital source of energy during fasting when the body is deprived of carbohydrates. Brain cells would prefer energy from sugars, being much more physiological. So, we have to understand that ketone body formation is a natural event under carbohydrate deprived situation (plan B). Ketosis presents a danger to some patients, having liver and kidney damage, and also type 1 diabetic. When people restrict their carbohydrate consumption, as in situations of starvation, lost in the jungle, or deliberate, the body turns to fat (Plan B), as an energy source. So as mentioned the fats are broken down to fatty acids to form chemicals – aceto-acetic, beta- hydroxyl-butyric acid and acetone. Same mechanism – production of excessive ketones can be activated by making people restrict their carbohydrates to very low levels and increasing the fat and protein consumption to a most un-physiological unnatural consumption situation. These are not balanced diets and a juggle with carbohydrates, proteins and fats. The late Dr Robert Atkins advocated this diet to slim, and many variations of this ketogenic diet appeared in the market, subsequently. The rationale involved here is that when carbohydrates are restricted the body turns to fat for energy requirements ( Continue reading >>

Ketones 101: Exploring The Benefits Of Exogenous Ketone Use

Ketones 101: Exploring The Benefits Of Exogenous Ketone Use

Walk into any supplement store and you’ll see the shelves adorned with what seems like an endless number of products making too-good-to-be-true claims: Lose weight in 24 hours! Lose two inches in two weeks! Between excessive praise and pushy salespeople, it can be difficult to know which supplements are reasonably worth trying—and why. So, when exogenous ketone supplements started showing up on the market, we were honestly a bit skeptical: Are these new supplements worth incorporating into our regimens, and are their apparent benefits backed up by actual scientific research? Today’s post is dedicated to explaining how we came to conclude that yes, exogenous supplements are worth including into your daily routine, and we’re about to tell you why. What are Exogenous Ketones? Simply put, the term “exogenous” refers to things that come from outside the body. Supplements are therefore considered exogenous because you ingest them rather than producing the contents of that supplement inside the body. The opposite of exogenous is “endogenous,” which refers to things that you do produce within your body. To define what “ketones” are, we need to briefly talk about how our metabolism works. Whenever you eat carbohydrates, they’re broken down into glucose (or sugar), which provides your body with the energy it needs to function; however, when you utilize a low-carb diet and don’t have enough glucose, your body adapts by looking for other sources of energy in the body. Eventually, it will turn to your fat cells. Whenever fats are broken down for energy, ketone bodies are produced as a result. Glucose is no longer your body’s primary fuel source, ketones are. (It’s important to note that ketones are always present in the blood, but their levels increase du Continue reading >>

Understanding Ketosis

Understanding Ketosis

To gain a better understanding of ketosis and the ketogenic diet, it is important to take a look at the physiology behind the diet. If you recall from the article What is a Ketogenic Diet? the goal of a ketogenic diet is to induce ketosis by increasing ketone body production. A key step in understanding the diet is to learn what ketosis is, what are ketones and what do they do. “Normal” Metabolism Learning the basics of the various metabolic processes of the body will better your ability to understand ketosis. Under the normal physiological conditions that are common today, glucose is our body’s primary source of energy. Following ingestion, carbohydrates are broken down into glucose and released into the blood stream. This results in the release of insulin from the pancreas. Insulin not only inhibits fat oxidation but also acts as a key holder for cells by allowing glucose from the blood to be shuttled into cells via glucose transporters (GLUT). The amount of insulin required for this action varies between individuals depending on their insulin sensitivity. Once inside the cell, glucose undergoes glycolysis, a metabolic process that produces pyruvate and energy in the form of adenosine triphosphate (ATP). Once pyruvate is formed as an end product of glycolysis, it is shuttled into the mitochondria, where it is converted to acetyl-CoA by pyruvate dehydrogenase. Acetyl-CoA then enters the TCA cycle to produce additional energy with the aid of the electron transport chain. Since glucose is so rapidly metabolized for energy production and has a limited storage capacity, other energy substrates, such as fat, get stored as triglycerides due to our body’s virtually infinite fat storage capacity. When a sufficient source of carbohydrates is not available, the body adap Continue reading >>

How Is The Production Of Atp From Ketone Bodies Similar And/or Dissimilar From It By Glucose?

How Is The Production Of Atp From Ketone Bodies Similar And/or Dissimilar From It By Glucose?

Ketone bodies (acetoacetate, acetone and 3-hydroxybutyrate) are produced in the liver by the process of ketogenesis in the course of normal metabolism and in increased amounts when large amounts of fats are rapidly metabolised. They enter the circulation whence acetone is largely excreted in the breath and urine while acetoacetate and 3-hydroxybutyrate are taken up by other organs such as the heart, brain and muscle. In these organs, but not in the liver which lacks the necessary transferase enzyme, the ketone bodies are converted back to acetyl-coenzyme A by the process of ketolysis. This joins the pool of acetyl-coenzyme A produced by the catabolism of glucose during glycolysis and is broken down by the citric acid (TCA) cycle and oxidative phosphorylation with the accompanying production of ATP. The metabolism of carbohydrates and fatty acids (and some amino acids) are then highly integrated through the common intermediate acetyl-coenzyme A and the key metabolic pathway of the citric acid cycle. Continue reading >>

Ketone Bodies

Ketone Bodies

Ketone bodies Acetone Acetoacetic acid (R)-beta-Hydroxybutyric acid Ketone bodies are three water-soluble molecules (acetoacetate, beta-hydroxybutyrate, and their spontaneous breakdown product, acetone) that are produced by the liver from fatty acids[1] during periods of low food intake (fasting), carbohydrate restrictive diets, starvation, prolonged intense exercise,[2], alcoholism or in untreated (or inadequately treated) type 1 diabetes mellitus. These ketone bodies are readily picked up by the extra-hepatic tissues, and converted into acetyl-CoA which then enters the citric acid cycle and is oxidized in the mitochondria for energy.[3] In the brain, ketone bodies are also used to make acetyl-CoA into long-chain fatty acids. Ketone bodies are produced by the liver under the circumstances listed above (i.e. fasting, starving, low carbohydrate diets, prolonged exercise and untreated type 1 diabetes mellitus) as a result of intense gluconeogenesis, which is the production of glucose from non-carbohydrate sources (not including fatty acids).[1] They are therefore always released into the blood by the liver together with newly produced glucose, after the liver glycogen stores have been depleted (these glycogen stores are depleted after only 24 hours of fasting)[1]. When two acetyl-CoA molecules lose their -CoAs, (or Co-enzyme A groups) they can form a (covalent) dimer called acetoacetate. Beta-hydroxybutyrate is a reduced form of acetoacetate, in which the ketone group is converted into an alcohol (or hydroxyl) group (see illustration on the right). Both are 4-carbon molecules, that can readily be converted back into acetyl-CoA by most tissues of the body, with the notable exception of the liver. Acetone is the decarboxylated form of acetoacetate which cannot be converted Continue reading >>

How Does The Body Adapt To Starvation?

How Does The Body Adapt To Starvation?

- [Instructor] In this video, I want to explore the question of how does our body adapt to periods of prolonged starvation. So in order to answer this question, I actually think it's helpful to remind ourselves first of a golden rule of homeostasis inside of our body. So in order to survive, remember that our body must be able to maintain proper blood glucose levels. I'm gonna go ahead and write we must be able to maintain glucose levels in our blood, and this is important even in periods of prolonged starvation, because it turns out that we need to maintain glucose levels above a certain concentration in order to survive, even if that concentration is lower than normal. And this of course brings up the question, well, how does our body maintain blood glucose levels? So let's go ahead and answer this question by starting off small. Let's say we have a mini case of starvation, let's say three or four hours after a meal. Your blood glucose levels begin to drop, and so what does your body do to resolve that? Well, at this point, it has a quick and easy solution. It turns to its glycogen stores in the liver. Remember that our body stores up these strings of glucose inside of our body so that we can easily pump it back into the blood when we're not eating. But unfortunately humans only have enough glycogen stores to last us about a day, so after a day of starvation, our body's pretty much reliant exclusively on the metabolic pathways involved in gluconeogenesis, which if you remember is the pathway by which we produce new or neo glucose. And we produce this glucose from non-carbohydrate precursor molecules. So let's think about what else we have in our body. Remember that our other two major storage fuels are fats, and we usually think about fatty acids containing most of th Continue reading >>

Beta-oxidation & Ketone Body Metabolism Flashcards Preview

Beta-oxidation & Ketone Body Metabolism Flashcards Preview

- stored in adipocytes - when blood glucose levels are low, hormones (cortisol and epinephrine) activate hormone-sensitive lipase - hormone-sensitive lipase cleaves triglycerides into glycerol and free fatty acids, which are released into the blood - (glycerol is H2O soluble, but fatty acids require albumin to traverse the blood) - to power gluconeogenesis! - gluconeogenesis requires ATP (and since this is occurring in the starved state, we need to get ATP from alternate sources); in addition, acetyl-CoA is needed to turn on pyruvate carboxylase, which begins gluconeogenesis - the acetyl-CoA is then used for ketogenesis - B-oxidation moves high energy electrons from the beta-carbon (3rd carbon) of the fatty acid and uses it in the ETC to make ATP (in the liver this ATP is used to power gluconeogenesis, in other cells, this ATP is used for their own needs) - B-oxidation also creates acetyl-CoA, which is used to create ketone bodies in the liver, and is used to create more ATP via the TCA cycle in other cells for their own needs - occurs in the mitochondrial matrix (so any cell with mitochondria can generate ATP via B-oxidation; again, RBCs lack mitochondria so they can NOT) - 1) fatty acids diffuse from the cytoplasm into the outer mitochondrial membrane, where it is attached to a CoA to form FA-CoA (this requires an enzyme, CoA, and ATP) - 2) FA-CoA then becomes FA-carnitine via carnitine acyltransferase-1 (CAT-1) - 3) FA-carnitine enters the matrix via carnitine transporters in the inner mitochondrial membrane - 4) in the matrix, FA-carnitine is returned to FA-CoA via CAT-2 - defective CAT-1, carnitine transport, or CAT-2, resulting in muscle aches, weakness, myoglobinuria, etc. - (it's myopathic, because muscles are the most affected due to their high energy demand) - Continue reading >>

Dublin Institute Of Technology

Dublin Institute Of Technology

Size: 25 Glucose is used as our primary energy source acids get stored for later use. • Glucose fuels us for about six hours, and once it runs out we rely of glycogen stores to produce energy • Ketone bodies are produced from fatty acids when liver glycogen is entirely depleted, and are used for energy • Once the fats are broken down, your body turns to breaking down protein in muscles, essentially wasting away your muscles. • Breaking down protein and releasing amino acids into the bloodstream will produce more glucose In diabetes, hepatocytes cannot efficiently take up glucose to use as a fuel. Acetyl-CoA accumulates in the hepatocytes and are converted into ketone bodies as the TCA cycle is slowed Increased conc. of acetoacetate and D-β-hydroxybutyrate lower pH= acidosis (coma, death) Acetoacetate & β hydroxybutyrate minimal in blood & minimally produced by hepatocytes. Most acetyl CoA fatty acid or pyruvate oxidation enter the TCA cycle only if fat and carbohydrates degradation are balanced. Continue reading >>

Lipid Metabolism

Lipid Metabolism

on on Fats (or triglycerides) within the body are ingested as food or synthesized by adipocytes or hepatocytes from carbohydrate precursors ([link]). Lipid metabolism entails the oxidation of fatty acids to either generate energy or synthesize new lipids from smaller constituent molecules. Lipid metabolism is associated with carbohydrate metabolism, as products of glucose (such as acetyl CoA) can be converted into lipids. Lipid metabolism begins in the intestine where ingested triglycerides are broken down into smaller chain fatty acids and subsequently into monoglyceride molecules (see [link]b) by pancreatic lipases, enzymes that break down fats after they are emulsified by bile salts. When food reaches the small intestine in the form of chyme, a digestive hormone called cholecystokinin (CCK) is released by intestinal cells in the intestinal mucosa. CCK stimulates the release of pancreatic lipase from the pancreas and stimulates the contraction of the gallbladder to release stored bile salts into the intestine. CCK also travels to the brain, where it can act as a hunger suppressant. Together, the pancreatic lipases and bile salts break down triglycerides into free fatty acids. These fatty acids can be transported across the intestinal membrane. However, once they cross the membrane, they are recombined to again form triglyceride molecules. Within the intestinal cells, these triglycerides are packaged along with cholesterol molecules in phospholipid vesicles called chylomicrons ([link]). The chylomicrons enable fats and cholesterol to move within the aqueous environment of your lymphatic and circulatory systems. Chylomicrons leave the enterocytes by exocytosis and enter the lymphatic system via lacteals in the villi of the intestine. From the lymphatic system, the chylo Continue reading >>

What Are Ketones And Are They Healthy?

What Are Ketones And Are They Healthy?

What Are Ketones and Are They Healthy? If you are up on your health news or follow anyone in the health field, you have likely heard the term ketogenic diet. The goal of the ketogenic diet is to adapt the body to utilize fat as its primary fuel source instead of sugar. The body does this by first converting fat into what are called ketones that the cells can then burn as fuel. It is at this point that I typically get asked, what are ketones? In this article, I am going to clear up any gaps, explain exactly how ketogenisis works, and why it can be so beneficial for the human body. Biological Role of Ketones For our ancestors, eating three meals a day just wasn’t a thing. Instead they would hunt and forage for the foods they could find. When there wasn’t food, they wouldn’t eat. What this means is that sometimes they would go for days at a time with no food. To sustain life during times of scarcity, the body is thought to have developed the ability to utilize fat as an alternative fuel source. In a traditional nutrition course, you would learn that sugar is the body’s primary fuel source while fat is a secondary fuel source. When sugar stores are burned up, the cells then convert to burning fat as an energy source. What we are finding out now is that fat can actually be a healthier and more sustainable source of energy. Our Society Is Full of Sugar Burners Modern day, we have an abundance of food that is available to us at all times. Most of us regularly eat three meals a day with intermittent snacking in between. This kind of frequent eating, along with an overemphasis on carb-rich and sugary foods, causes a reduced ability to burn fat. As these foods damage our bodies on a metabolic level, we actually lose the ability to produce ketones. This type of reliance on Continue reading >>

Ketone Bodies In Energy, Neuroprotection, And Possibly In The Effects Of Dietary Restriction

Ketone Bodies In Energy, Neuroprotection, And Possibly In The Effects Of Dietary Restriction

The Durk Pearson & Sandy Shaw® Life Extension NewsTM Volume 6 No. 4 • September 2003 Ketone Bodies in Energy, Neuroprotection, and Possibly in the Effects of Dietary Restriction Ketone bodies, natural metabolites produced from fatty acids, are sources of energy that can be used when there is insulin deficiency (which may be pathological, as in diabetes, or as a result of consuming low dietary carbohydrate) or mitochondrial senescence. Ketone bodies are found in moderate amounts in prolonged human fasting and in type 2 diabetes. Interestingly, ketones are very efficient sources of energy. One paper1 reports that the efficiency of cardiac hydraulic work (in rat hearts) was 10.5% in hearts perfused with glucose alone, and increased to 28% in combination with insulin, to 24% with ketones, and to 36% on addition of the combination. Addition of insulin, ketones, and the combination increased acetyl CoA (in the tricarboxylic acid cycle) 9-fold, 15-fold, and 18-fold, respectively, with corresponding decreases in CoA. “Addition of insulin increased the efficiency of hydraulic work per mole of oxygen consumed in [rat] heart 28% by decreasing oxygen consumption by 14% and increasing cardiac work 13%. Addition of ketones, on the other hand, increased the efficiency mainly by increasing hydraulic work, at the same time decreasing oxygen consumption by only a small percentage.” The authors propose that “The increase in efficiency caused by ketones therefore was compatible with a decrease in proton leakage across mitochondrial membrane due simply to a decrease in potential, as has been previously suggested.” We have written earlier in this newsletter on the hypothesis that increased mitochondrial membrane potential (which increases free radical production in mitochondria) i Continue reading >>

Ketone Body

Ketone Body

ketone body n. Any of three compounds, acetoacetic acid, acetone, and beta-hydroxybutyric acid, that are ketones or derivatives of ketones and are intermediate products of fatty acid metabolism. Ketone bodies accumulate in the blood and urine when fats are being used for energy instead of carbohydrates, as in individuals affected by starvation or uncontrolled diabetes mellitus. Also called acetone body. American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved. ketone body n (Biochemistry) biochem any of three compounds (acetoacetic acid, 3-hydroxybutanoic acid, and acetone) produced when fatty acids are broken down in the liver to provide a source of energy. Excess ketone bodies are present in the blood and urine of people unable to use glucose as an energy source, as in diabetes and starvation. Also called: acetone body Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014 ke′tone bod′y n. any of several compounds, as acetoacetic acid, acetone, and hydroxybutyric acid, that are intermediate in the metabolism of fatty acids and are produced in excessive amounts under certain abnormal conditions, as in diabetes mellitus. Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved. Noun 1. ketone body - a ketone that is an intermediate product of the breakdown of fats in the body; any of three compounds (acetoacetic acid, acetone, and/or beta-hydroxybutyric acid) found in excess in blood and urine of persons with meta Continue reading >>

How Your Body Fights To Keep You Alive When You’re Starving

How Your Body Fights To Keep You Alive When You’re Starving

The human body can go without oxygen for about five to ten minutes, and about three to eight days without water. But remarkably, people have been known to live upwards of 70 days without food. How is this possible? The answer lies in a series of evolved physiological and metabolic defenses that work to keep you alive for as long as possible in the unfortunate event that you don't have access to food. Just because you're starving doesn't mean you've become helpless. Here's how your body fights to keep you alive and active. By definition, starvation is a process. Our bodies are not like cars which immediately shut down when they're out of gas. When we experience prolonged low energy intake, and as long as water is available, our bodies enter into a successive series of metabolic modes. It's the body's way of recognizing that food is scarce, and that it needs to re-allocate resources in preparation for what could be an extended period. In essence, your body is buying you some valuable time to give you a fair chance of finding some food. 0-6 hours after eating Soon after eating, our bodies start to break down glycogen (molecules that store energy) to produce glucose (an important carbohydrate that fuels cells). When we're eating normally, we use glucose as our primary fuel source; all is well, we're happy, and in storage mode. Glucose gets packed into our liver and muscle, with the fatty acids getting stored around our body for (potential) future use. In terms of energy allocation, our brains require 25% of the body's total stored energy (which is a lot if you think about it), with the rest going to fuel our muscle tissues and red blood cells. We can go for about six hours in this glucose-burning mode, which is why we tend to get a bit cranky if we have to go without food f Continue reading >>

Ketones

Ketones

Excess ketones are dangerous for someone with diabetes... Low insulin, combined with relatively normal glucagon and epinephrine levels, causes fat to be released from fat cells, which then turns into ketones. Excess formation of ketones is dangerous and is a medical emergency In a person without diabetes, ketone production is the body’s normal adaptation to starvation. Blood sugar levels never get too high, because the production is regulated by just the right balance of insulin, glucagon and other hormones. However, in an individual with diabetes, dangerous and life-threatening levels of ketones can develop. What are ketones and why do I need to know about them? Ketones and ketoacids are alternative fuels for the body that are made when glucose is in short supply. They are made in the liver from the breakdown of fats. Ketones are formed when there is not enough sugar or glucose to supply the body’s fuel needs. This occurs overnight, and during dieting or fasting. During these periods, insulin levels are low, but glucagon and epinephrine levels are relatively normal. This combination of low insulin, and relatively normal glucagon and epinephrine levels causes fat to be released from the fat cells. The fats travel through the blood circulation to reach the liver where they are processed into ketone units. The ketone units then circulate back into the blood stream and are picked up by the muscle and other tissues to fuel your body’s metabolism. In a person without diabetes, ketone production is the body’s normal adaptation to starvation. Blood sugar levels never get too high, because the production is regulated by just the right balance of insulin, glucagon and other hormones. However, in an individual with diabetes, dangerous and life-threatening levels of ketone Continue reading >>

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