Difference Between Keto and Fat Adaptation
What is the difference between Ketosis and Ketoacidosis, Keto adaption and Fat adaption and something I refer to as metabolic flexibility?
So let’s start with the difference between Ketosis and Ketoacidosis.
Wikipedia says Ketosis is a metabolic state in which most of the body’s energy supply comes from ketone bodies in the blood, in contrast to a state of glycolysis in which blood glucose provides most of the energy.
Dr Peter Attia of Eating Acedemy says – Ketosis is a state, achieved through significant reduction of carbohydrate intake (typically to less than 50 grams per day), at which point the body makes a fundamental change from relying on glycogen as its main source of energy to relying on fat as the primary source of energy. In particular, the brain shifts from being entirely dependent on glucose, to being primarily dependent on beta-hydroxybutyrate – a so-called “ketone body.” Ketone bodies are chemical structures made by the liver (also somewhat in the kidney) out of fatty acids, primarily.
Ketosis is simply the mechanism in which the body begins to burn fat for fuel by producing ketones in the liver rather than glucose. This happens when carbohydrate/glucose is removed from the diet and the body begins to produce ketones, this is ketosis.
Ketoacidosis is typically a state that occurs in T1 diabetics and is a combination of high ketones and high BG, although it can happen in other situations including alcoholics. The cause is extremely elevated ketone levels of say 15 mmol or higher and high levels of Blood Glucose. That said there is need for concern should your ketones get above say 10 mmol. Basically what happenes, the body fails to manage or regulate ketone production causing uncontrolled ketosis. It happens when the individuals BG levels are elevated and the body can’t produce insulin, because they are T1 and don’t produce any, to get the glucose into cells. So it goes into emergency mode and starts burning everything it can find like fat and tissue from lean mass and bones and starts generating ketones to survive, but here’s the problem there is no insulin to lower BG and there is still no insulin to lower or manage ketones. So now you have a life threatening situation, remedied only by insulin. But this is not actually possible in a person who can produce insulin, even in small amounts. And a ketogenic diet is perfectly safe for Type ones as long as the monitor BG and BHB and does with insulin.
So another term we hear often is Nutritional ketosis, this is a term coined by Phinney and Volek refers to a blood BHB level between .5 mmol and 3 mmol or maybe even 4-5 however in a recent podcast Dom D’Agostino says over 1 mmol is preferable. This is term that is used to describe a certain level of ketones in the blood. Im sure you have seen the graph that shows a curve from 0 to 10+, the green zone is nutritional ketosis and over 3 to 10 is starvation ketosis, or what I like to refer to as therapeutic levels and then over 10 is the rage where ketoacidosis becomes possible. There is more than just fat burning benefits that come along with these levels of BHB, there’s emerging research that shows many things like protein sparing effects, decreasing of oxidative stress, gene expression, and many other great benefits still not completely known.
The difference between keto adaptation and fat adaptation is variable and there are a lot of different definitions and opinions on the subject. I do have a rather definitive explanation of both. Rather than define it lets describes what’s happening and the progression.
Before we get into I would like to address a very important topic. There is a misconception that you have to increase dietary fat during adaptation and this is not accurate. The machinery is already there, we just need to eliminate the glucogenic substrate from the body and it will happen on its own. If that were not the case anyone who is fasting beyond 24-48 hours would not be able to adapt and we know that is not the case based on Cahill’s work. Having said that, I would like to point out that during the adaptation period increasing fat will certainly help with the withdrawals from sugar and fatigue during the switch from glucose to fat.
I like to think of Keto adaptation as the point at which the body, primarily the brain has adapted to using fat, ketones for fuel. In his research George Cahill showed that to happen about the 4-6 week mark. During this time there are a few stages. In the first 24-48 hours is when the brain is still being powered by glucose. Then for the next several weeks the brain is using a mixture of glucose and ketones, however glucose is primary. This glucose needs are fulfilled by GNG. At some point again around that 4-6 week mark the brain begins using ketones as the primary fuel source and much less glucose. This is keto adaptation.
Speaking of adaptation, Steve phinney describes keto adaptation – as climbing to the top of a steep dune, once you eat carbs you slide back down and now you have to climb back up. In another interview Phinney he says most of the adaptation occurs in the first two weeks, but some of the fine tuning is going on four to six weeks after that.
At some point in the near future something I refer to as full adaption happens when there is a full mitochondrial turnover when all the mitochondria now operate on fat rather than glucose other than the few organs and cells that still require glucose. This is the start to fat adaption.
Fat adaption however, requires some effort and practice.
Fat adaption happens when the body is now efficient at burning fat at a higher rate for energy then before is the best way to describe that is. Take an endurance athlete who runs a mile in say 5 minutes at heart rate of 180 plus burning glucose the entire time. So now take that same athlete and put him on a ketogenic diet. Allow him to become keto adapted. He’s climbed to the top of the dune. His brain is functioning on mainly ketones and his entire mitochondrial system is now flipped over to a primarily ketone/fatty acid fuel source. If we wants to run that mile at a fat burning heart rate, meaning not needing glucose to fuel the run. He would be at a LISS, low intensity steady state, so let’s say he’s is 30 years old so that fat burning heart rate is going to be 150, 180 minus his age and now he runs out same mile in say 10 minutes however fast forward to the point of fat adaption when he becomes efficient at burning fat for fuel and he now runs that same mile at the same heart rate of 165-170 in 6 or 7 minutes or maybe even the same as before – because now his body is going efficient at burning fat, because he can better oxidize fat and at the same time he can burn fat at an increased HR. The body is actually getting better at utilizing both fuels simultaneously. So it’s burning fat and glucose at the same time in a ketogenic state. In fact in a conversation with Peter Defty, he explains how he now uses 200 minus age for his fat adapted athletes because of this. If you are not familiar with Peter and his work, check out the FASTER study and his website www.fatadaptation.com… This is the guy redefining the space of keto endurance athletes and has been before most of us ever even heard the word Keto.
So this now brings me to something metabolic flexibility. This is the state in which the bodies become efficient at switching back-and-forth from producing ketones to glucose in the liver so it is this is the state would you like our ancestors I believe that it was by the food source availability climate culture The majority of our species in my opinion floated in and out of ketosis, eating primarily protein and fat and any carbohydrate source then available. He didn’t find a potato or a kiwi and say, “this looks really good, but it’s going to screw up my macros and knock me out of ketosis!”
There is much research to be done on the subject and I think that Peter’s athletes and some practitioners of CKD and TD are illuminating the way into this. The guys are prime examples of metabolic flexibility, insulin sensitive, increased glycogen storage capabilities, enhanced glucose/glycogen uptake. The ultimate physical and metabolic specimen.
Keto saved me and it can save you too!
We are all individual as such our journey. Thanks for reading and be well!