Dr. Doron Sher - 'Understanding Ketones'

so I'm an orthopedic surgeon I'm good at anatomy I'm good at biomechanics I'm good at you know cutting things and putting them back together but really carbon chemistry was never a passion of mine and that's why I did orthopedics I didn't have to think about it ever again but but I needed to understand what was happening with ketones and and what the hype was all about so again I'm I try to make things as simple as possible and we're going back to this model that we can either burn glucose or as our primary fuel source or fad as our primary fuel source to get energy so in a nutshell this is what you need to know about ketones the fatty acids are released from the fat cell they travel through the blood into the liver in the liver there's this magic box which turns them into ketones ketones are released back into the blood and from the blood they go to the cell where they provide energy a certain number of them will evaporate and be blown off through your lungs and a certain amount of them will get excreted through your kidneys thank you very much so where does our energy come from when we eat food it's broken down into its small small bits that are useful to the body and the mitochondria is the powerhouse of the cell this is where most of the energy production takes place a major role for the mitochondria is production of ATP which is sort of the unitive of energy and this is used to transport stuff in and out of the cells create mechanical changes like getting muscles to contract and help synthesize or build new parts of the cell so at a mitochondrial level and that's what I'm showing you over here is what happens within the mitochondrial and don't get scared about all the chemistry and the chemical equations there's two major things I really want you to notice that both fats and glucose go into the mitochondria now in a standard diet type person about 50% of your energy comes from the carbohydrates and about 50% comes from the fats or fatty acids so this is people who are on a standard Australian diet these feed into something called the TCA cycle or Krebs cycle and I'll talk about a little bit more about that afterwards if you become fat adapted and you cut out the glucose the amount of glucose feeding into the system gets less the amount of fat feeding into the system gets more and for example after three or four days of having less glucose your brain can adapt to use the ketones instead of the glucose so again complex slide don't worry about remembering the details this is just an enlargement of this here there's a couple of things we need to know about one is called acetyl co a and the other is oxaloacetate so burning glucose as our primary source of fuel is known as glycolysis from carbohydrates we make acetyl co a which you see down here which enters something called the citric acid cycle up here and again you don't need to remember this this is more a conceptual thing that you need to understand from which down here the energy is released now it has to go full circle to come back again and if you're missing one of these ingredients it's a bit like missing a critical step in a recipe you know you don't have eggs you can't make the cake the whole thing will fall apart it's the same thing here and the critical thing that I want you to notice is this thing called oxaloacetate now ATP is very important but we only have limited stores of glucose and glycogen in the body to burn and I think people know that we all know that muscles have lots of glycogen but the problem is if my leg muscles have lots of glycogen and my arm muscles have run out of glucose there's no way of getting that glycogen from the legs up to their arms the only organ that can release glycogen is liver and send it to other parts of the body so when my arm blockage in is used up I get glycogen from the liver but when that's used up as well I've got no more glycogen and the only way to get more glycogen is then to eat it so with sustained exercise we will fairly quickly run out of our glucose and glycogen stores now gluconeogenesis is the body's ability to make its own glucose and that's why we're not worried about you know Brett the brain which needs glucose we will make enough glucose for the brain on our own without needing to eat it so I'm gonna go through the slide a couple of times and go through it relatively slowly because this is what you need to understand for ketones this is the crux of the science of low carbohydrate energy production basically this is what happens normally carbohydrates go through acetyl co a go through that big circle that I showed you beforehand and you end up with energy or ATP but if we cut out the carbohydrates what happens we don't have any acetyl co a to go into the cycle so what happens the body says okay well I still need a so Talco a what am I going to do I'm gonna make the acetyl co a from the fat that puts it back into the citric acid cycle now the problem at this stage is we haven't given the body carbohydrate or glucose so the body says okay I'm going to make my own glucose by going through gluconeogenesis but in order to do that it uses up the oxaloacetate because that's required for gluconeogenesis and what does that do stops the circle going round so we don't have any more ATP now this is a problem as the ATP isn't produced the acetyl co a doesn't have anywhere to go and so we get increased acetyl co a what happens to increased acetyl co a well we can turn it into ketones and the ketones can be used for energy so I'll run through that one more time you cut out the carbohydrates mmm that makes no asset alkaway from there so we've got to get acetic away from our fat when we don't have carbs we use up our oxaloacetate to make glucose that blocks off our energy pathway this way we get an increase in asset ROA which causes ketone production and ketones are used as an energy source so after about three days the brain gets about 25% of its energy from ketone bodies and after four to five to six days that can go up as much as 70 percent so you can have a massive increase in your ketone energy supply to the brain now the level of ketones or ketone bodies in our bloodstream can be measured and this reflects the amount of fat that's being broken down but we'll talk about that a little bit a little bit more later at a cell mitochondrial level the ketone bodies are taken up Andry converted into acetyl co a where they can turn them into energy so remember our fat cell from the previous talk as well the hormone sensitive lipase is breaking up the triglyceride the fatty acids are going out and then they go ahead and go through the liver into the cell and they're then burned now fatty acid in the blood can either come from food that we eat or our in stores if you're eating lots of fat you don't need to use up your own stores so you've got to be careful with how much you eat if you're looking to burn your own stores so what happens when the fatty acids reach the liver well you remember that the cell wall has this barrier to get through the same thing happens in the mitochondria that the keto the the the fatty acid can't get through there now a lot of people are very worried about protein a lot of people have heard of carnitine and you don't really need to worry too much about this but the only way that that the long-chain fatty acids can get into the motor Maria is using a carnitine pathway so once they're in the liver the fatty acids allow allow asset alkaway to be produced and then eventually it goes through becoming acetyl acetone Co a goes through hmg-coa and you need enzymes to be able to do this and you form acetyl acetate acetyl acetate can is released into the blood and some of its converted it to beta hydroxy butyrate but that requires energy for that to happen and some of it spontaneously becomes acetone which is quite volatile and can go up into your lungs and you can blow it off out through your lungs now there is an enzyme that also does that and so if you get a lot more acetyl acetate that can drive that a little bit more so the reverse process can take place as well that you can start with your beta hydroxy butyrate and run back through the system to give you the SS Otago way to be able to produce the energy now the question is why does the liver not just use up all the ketones that it's making because if it can go in both directions then it should just end up in this endless cycle where it's making and burning and making and burning but luckily the body's pretty clever we're missing a particular enzyme in the liver which is known as thiolase and that's what's stops the liver from eating and using its own ketones now again simple orthopedic surgeon when I was first trying to learn about all of this I thought you know what's the ketone so I went to Wikipedia as most people do and I read this and it just bamboozled me I mean you know seriously that doesn't help me at all so I then look look further into Wikipedia and it says ketone not to be confused with ketone bodies I'm thinking everything that I've read in the literature is just using these terms interchangeably ester acid ketone body and there is actually a fair bit of science behind the different things so ketone group has has a double bond with an oxygen and carboxyl group over there and acetone is certainly one of those ketones and not to put too fine a point of it but even Wikipedia puts beta-hydroxybutyrate acid rather than putting beta hydroxy butyrate as the picture when you're talking about ketones and there's this complex pathway where you can remove a proton from it but at the end of the day unless you're actually a scientist it probably doesn't matter exactly what term you're using so if you read ketone body versus ketone versus ask ester or acid it does make a difference from a scientific perspective but from the general weight loss community the discussions don't seem to make that much difference so why are we talking about nomenclature I want to briefly discuss ketoacidosis because maybe every second week I get this question you're going keto oh my god that's dangerous so and I think it's important for us to understand ketoacidosis just to be able to tell people look you're simply wrong this is not a realistic problem for us so if you remember our graph showing fat burning versus fat storage and the amount of insulin that we have we can see that when insulin is low on the x axis fat metabolism is high as insulin levels increase we get a sharp drop in fat metabolism so this reflects the fact that even small amounts of insulin are going to have a large impact on our fat burning ability this is very important for our next slide so this is a graph of pH which is the acid-base balance of the body and this is the amount Ketones you have in your body so again this is a quick show of hands who are these who in the audience is ketogenic okay who tests their ketones excellent now has anybody had a ketone level of above two above four above six amazing above eight so we've got one person anybody up to 12 with their ketone levels give me a number what's the highest that's ever been fifteen all right so fifteen fifteen is very very high for most people and a ketogenic diet and it's almost always associated with something like an extended fast you know twenty thirty day fasting is very unusual for people to get that high the majority of people are probably going to be in the sort of 0.5 to 2 ratio a lot of the time and more people will get higher as time goes by so the normal upper limit of nutritional ketosis is defined as 3 but I mean this is an arbitrary number it doesn't really mean that very much starvation ketosis is often about five but you know clearly in our audience here we've got some you know real goers who are getting up you know five eight ten sort of level and one one extreme example over there so the absence of insulin signals the body the energy shortage so if you're in ketoacidosis you've got glucose but you can't get the glucose into the cells the brain reacts saying I need more energy where can I get the energy from it can get it from ketones so the brain sends out a signal and say produce lots of ketones and the ketone production goes ahead at a breakneck speed but this can only happen in the absence of insulin the body tries to blow off the extra acetone you remember I showed you the pathway that it goes to the cells or some to the lungs and so you start to breathe faster and as you start to breathe faster the acid-base balance of your body and you become acidotic or you have more acid in your system because you're blowing it off and you see that as a pH drop so the number here goes down towards 7 then you get dehydration and that impairs the renal expression of the hydrogen ions which is another acid and so your pH eventually approaches 7 now I've got here moderate ketoacidosis at the level of about 1315 which is where you were would put you over here and even that is still in a safe zone if you've got even a hint of insulin because as soon as the insulin hits the system what's going to happen your fat burning' drops therefore your fat product for your fat burning' drops therefore your ketone production stops so this kid met then a diabetic ketoacidosis really is only a problem if you're a type 1 insulin-dependent diabetic who doesn't have any insulin on board all of us are able to produce insulin when our ketone levels start to get higher the body responds by giving it some insulin to stop the fat burning and stop us getting into this keto acidotic state so just to summarize a complete absence of insulin is required for ketoacidosis so it's not going to happen to anybody on a diet where they're making their own insulin all right what about measuring ketones you can do it multiple ways breath urine finger prick the finger prick test detects beta-hydroxybutyrate as opposed to acetone or cito acetic acid and the blood levels are measured through a test that that uses the single beta hydroxy butyrate dehydrogenase and it's got an nad plus as an electron accepting cofactor does that really matter no not really the fact is it's a very accurate measure of the beta hydroxy butyrate ketone in your in your blood at that particular in time so it's obvious already that some individuals have different insulin responses and those people will be able to have a different amount of carbohydrate to somebody else rod mentioned this at the beginning of the talk some people will be 20 grams a day some people 50 some people are hundred and your metabolism your fat metabolism will be affected by the amount of insulin that you have so this is an example of a food diary from one of the patients in the clinic so you can see here initially the patient's doing pretty well they testing themselves at nighttime they're running one point one point seven point four they're burning fat they're eating steak and coleslaw egg macadamia nuts now what happens next they have a small piece of sponge boom point two all right so this particular person can monitor their blood levels and understand the food how the food is affecting them now this varies enormously between different individuals you know the patient goes back on their good diet and what happens point seven again they think oh I'll just have that little piece of toast boom down to point to again alright so you can use the ketone testing to actually monitor your response to fat burning you also need to understand that what we what we do is eat food we don't eat ratios on an app and and the problem with following your ratios too closely is that the food combination actually creates different insulin responses so we know that protein causes about half the insulin spike of carbohydrate but double that of fat and that's a lot of the reason that we get people to limit their proteins you've got to have enough protein for you to be have your building blocks but not so much protein that you stimulate an insulin spike and stop your fat burning so what do we consider Target ketone levels look this is incredibly difficult and depending on what you're trying to achieve for fat-burning I would say these are probably the appropriate levels but I had a long chat to donal main when she was here in Australia and she's an oncologist and she's told me that when she runs her patient she runs them at add average between three and four while the patients are going under undergoing chemotherapy and radiotherapy so it just depends on what your goals are as to what advice you're going to be given as to how to run your ketones now there isn't an absolutely better level of ketones and it's very important to understand that having a higher ketone level doesn't necessarily make you burn more fat and lose more weight because it depends where the ketones are coming from you can drink exogenously tones and get a very high ketone level but what that's going to do is stop the body burning your own ketones and stop your body burning fat so having a champion I've got a six level of ketones where I've drunk exogenous ketones doesn't necessarily help you lose weight and Paul I'm sure will talk to you a little bit more about that so to lose weight you need to listen to your hunger signals and most of us doing this way of eating will probably only eat once or twice a day very rare for us to eat three or four times a day but occasionally you will be hungry and on those days you will eat more there's nothing wrong with learning what hunger is and following that pathway so weight loss requires negative energy balance ketosis tells you that you're able to metabolize fat but you do need a negative energy balance to be to need to metabolize your own fat and that really is a key point to understand so I say that one more time ketosis shows that you're able to metabolize fat but in order to burn your fat you're going to need a negative energy balance so what are the metabolic advantages of nutritional ketosis well one it shows you that you're able to metabolise you're fat number two it tells you your blood glucose levels and therefore your insulin levels are controlled and number three it reduces hunger and therefore it's easy to reduce your food intake so I would commend you to be coming here to genic if you're not because of all of the advantages thank you

Channel: Low Carb Down Under

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Keywords: Low Carb Down Under, LCDU, www.lowcarbdownunder.com.au, Low Carb Sydney 2017, Doron Sher, Nutritional Ketosis, Ketogenic Diet, LCHF, Low-Carbohydrate Diet, Low Carb Healthy Fat, Ketone Bodies, #LowCarbSyd, Kreb Cycle, Weight Loss, Carbohydrate Restriction

Id: z7Lx-GHGMBc

Length: 22min 13sec (1333 seconds)

Published: Fri Jun 22 2018