Dr. Jason Fung on Intermittent Fasting [Brain Fuel]

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Intermittent fasting for weight loss
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Intermittent fasting for weight loss


Jason Fung, nephrologist and best-selling author, shares his experiences utilizing an individualized approach to fasting, to successfully treat dozens of overweight, metabolically ill, and diabetic patients. And why being a doctor who specializes in kidney disease gives him a unique insight into early indications of metabolic disease. Let’s listen to Dr. Jason Fung! 


>> Jason Fung: I think that this is a very important health problem. And just to give you a little bit of background, I’m a kidney specialist. So, that means that I did my medical training and eventually I spent another five years doing my specialty training in kidney disease.


And the most common cause of kidney disease, by far, is type two diabetes. So I started practicing about 15 years ago and we had just been seeing more and more people with kidney disease and as their kidneys fail, we put them on dialysis and so on, and we treat them with medications. But it soon became fairly clear that people were not really getting better, despite the fact that I was giving them lots and lots of medications. And it gets to the point where people kind of give up and this is the real problem.


So type two diabetes, if you look at what a lot of people say, is considered a kind of chronic and progressive disease. We hear this all the time. Patients will come in and they’ll say, “Oh, well. I have it. I have life. This is nothing I can do about it.” The truth is, this is not really true. It’s never really been true. And it’s very easy to prove. So if you have somebody who is overweight and has diabetes, if they lose weight, then their diabetes very frequently goes away.


So, therefore, the disease itself is not a chronic and progressive disease. It’s not like aging where you will get older, no matter what you did. It’s just nothing you can do about it. So, therefore, you kind of give up trying to get younger. But type two diabetes is not like that. It’s a disease, but yes, it can be reversed. You have to do it in the proper way. And what was very clear was that the conventional treatment of type two diabetes was not working and the diets that we were prescribing were not working. The lifestyle interventions, we are prescribing, was not working. So then doctors would eventually resort to giving a lot of medications and those medications were not making people healthier. So what people typically did was that they got diagnosed with type two diabetes. They got started on lifestyle treatments, usually, a low calorie-reduced diet, and nobody got better. So then doctors started the patients, first one and two, then three, then four and insulin and then more insulin.


And when you look at it logically, what you see is that if you are taking more and more medications over a period of 10 – 15 years, your diabetes is not getting better. It’s only getting worse. So if you think about it, what we have is, let’s put these two facts together. One, type two diabetes is largely a reversible disease.

And number two, almost nobody was getting better. Well, when you put those two together, the only thing you can say is that the treatment is completely incorrect.


And that’s kind of where I started from. So if you kind of go back and say, “Okay Well, if type two diabetes relies on losing weight to reverse it, well, then that’s what we need to treat because that’s the root cause of the type two diabetes.” That’s not what we’re doing. We’re getting a diet, a low-fat diet or a calorie reduce diet that had almost no chance of success for weight loss. And again, this is one of those things, where nobody wants to be the bad guy and say what we’re doing, is really stupid.


This low fat, calorie-reduced diet. It’s really bad. It’s like the story – the emperor with the new clothes, nobody wants to say that the emperor’s naked. The thing is that if you look at large databases in the United Kingdom, for example, the probability of going from obese to normal weight or morbidly obese to normal weight is somewhere on the order of 0.2% – 1%. That’s your success rate. In other words, we were prescribing a diet that had about a 99 to 99.8% failure rate.


That’s ridiculous! And that squares exactly with the clinical experience. That is, everybody’s done it and nobody succeeded. So no wonder people were not reversing their type two diabetes. They were not losing weight. Then you go to medications and we were giving people things like insulin which causes weight gain. So if the reversal of type two diabetes depends on losing weight and the doctors prescribe medication that causes weight gain, guess what? Your blood sugars may be better, but your diabetes is only going to get worse.


And the thing that’s funny is that patients knew this. So I would prescribe insulins. I did this many years before I kind of changed. I would give them insulin. They would gain weight. And they come back and they say, “Woah! This insulin you gave me made me gain 20 pounds. You tell me that I need to lose weight, then you give him medication that makes me gain 20 pounds. How is that good?” And the answer is it’s not.


As they gain weight, their diabetes gets worse and they need more insulin. As they take more insulin,  they gain more weight, which makes diabetes worse. So they’re stuck in a vicious cycle that’s only getting worse. So that’s when I started really thinking about it. It was about 2008 when really the studies caught up to my kind of nagging doubts about what we are doing. And remember, this is really the core of everything I was doing day in and day out. It’s very hard to admit that you studied for like 11 years in school and worked for another 10 years and realized that, “Hey!  Most of what you do is not very useful. It might have been making people worse!”


 It’s not very easy to admit that. But that’s where the point where I was. In 2008 was when two very important studies came out in obesity medicine and type two diabetes medicine. So in obesity medicine, you started to get the results of a lot of these studies on low carbohydrate diets, which were relatively high in fat. And I, along with lots of other doctors, thought that it was going to be a disaster. This sort of  Atkins diet! The Atkins diet in the late 1990s was all the rage. And doctors like me thought it was going to be killing people left and right. So all of these studies were done with almost the express purpose of proving how bad these diets were. And then something happened. People were getting really healthy. Diabetes was better, their cholesterol was better. They were losing weight. It was ridiculous. But that’s what the evidence showed, that these high-fat diets, these low carbohydrate high-fat diets were actually not bad at all. And so that was a real eye-opener for me. And then very shortly after in 2008, in the same year, some of the studies on type two diabetes were coming out. So just to get back to type two diabetes which is characterized by high blood glucose. And for a long time, we thought that it was all about knowing that you should give as much medication as you needed to to get that down. And that was the core of what we did in medicine for like 30 – 40 years.


We talk to our medical students. We all believe that we all practice. So, a couple of studies came out – the important study, the advanced study, the VADT study, the origins study – there are multiple, multiple million-dollar, multi-national randomized controlled trials. And what they showed was that if you took two groups, one group you gave a lot of medication to get their blood sugars really down closer to normal. In one group, you didn’t care so much and give as much medication. So what they showed was that, yes, you get more medications, the blood glucose got better.


But what they also showed was that even when you gave more medications, people were not healthier. That is, they were still having the same heart attacks, still having the same strokes. The first study to come out actually showed that the high medication group, actually, were dying at a much faster rate. And so it’s like, “Okay, well, here it is!” Yeah, it was incredible. It was this everything that we had been doing for type two diabetes had just been proven completely wrong! From what we had done in medicine, was that focused so myopically on getting that blood glucose down and it wasn’t making people healthier.


They’re having the same heart attacks, strokes, kidney disease, everything. So why would you take a medication if it wasn’t going to make you healthier? That was the real question. And so it was a complete paradigm shift in type two diabetes that we needed to make. But unfortunately, over the next 5 or so, 10 years, nobody really took that next step and say, “Well, what do we need to do?” In fact, we just kept doing the same thing that we used to do, even though we just proved it completely ineffective.


That’s where kind of things started. So I really started to look at type two diabetes and trying to understand what type two diabetes is, what insulin resistance actually is, and how we can make people lose weight in order to start reversing their type two diabetes. So that’s when I started. Shortly thereafter, we started our program, the intensive management program, where we use a low carbohydrate diet and intermittent fasting to really start to get these type two diabetics and reverse their disease. And it was funny because as soon as I started, some of the stories were just ridiculous!


Like people who were coming in with hundreds of units of insulin for 10 years. And in two or three months, we have them off everything and their blood glucose is just almost normal. So 15 years of diabetes, which was reversing in like 3 months, was ridiculous! How quickly people were getting better. And that’s why I started to kind of expand and also to do some of the lectures about type two diabetes. And it turns out they’re both related diseases of too much insulin, which is essentially the problem.


So where we had gone wrong was that we are using a diet that’s very stimulating insulin, that is low fat, carbohydrate diet. And if you eat all the time, you stimulate insulin. So the problem, which is too much and we’re making it worse. If you do the opposite, if you cut down the carbohydrates, the refined carbohydrates and you reduce the number of times they eat, then you’re going to lower the insulin. So if the entire disease is too much, then you need to lower the insulin and that makes sense. 


What we were doing was that we were treating a disease of too much insulin with more insulin and then wondering why it wasn’t working. That’s crazy! It’s like treating an alcoholic with alcohol and then wondering, “I wonder why his alcoholism doesn’t get better?” It was the same ridiculous sort of mentality that we had. So we were treating this disease by making it worse and then saying, “Well, it’s worse because that’s just the way it is!” The medical community, the research community has a lot invested in this sort of paradigm. That is, there’s a lot of people who have built their careers on doing it this way. And there is a lot of money to be made by selling insulin and selling drugs and so on. It’s a multibillion-dollar business, so nobody wants to know about it. That is if you are a researcher, for example, and you’ve just spent the last 25 years trying to prove how you need to give more insulin to a disease of too much insulin or you need to give insulin, which makes a gateway even though the problem is that they’re overweight in the first place. If you just spent twenty-five years, it’s very hard for people to say, “Oh well. Guess what? I’m wrong.”  It’s making it worse. And the same thing with the drug companies. They have invested a lot of money into developing new types of insulin. The fact that they don’t make people healthier is entirely beside the point. All you need to do is get doctors to prescribe it. And these are multi-billion dollar drugs and that’s money. So they’ve invested a lot in it.


So, in order for people to change, it’s going to be very difficult. But there’s a good side to all this. The good side is that we don’t need them to take our side. We can start, right now, by telling people the truth and people can start using their own diet without their doctors, without the dieticians help. Just do it and get healthier. And that’s the real power of what you do, is that you can raise awareness of this and people can actually start to look into it.


And they don’t need anybody to do this for them. Because the diet is something that they take themselves without interference from anything else. The whole issue is that it’s not really just the weight! It’s actually the fat inside the organs, that is the problem. And sometimes that is not visible. So if you look at, for example, a Chinese population, they develop type two diabetes with an average body mass index of 23.7, which is actually completely normal. So 20 to 25 is normal and it just doesn’t look like they have type two diabetes.


Americans, for example, will develop type two diabetes with a body mass index closer to 28, which is on the overweight side, close to obese. So it’s not just the overall weight that’s important, but actually, probably the most important factor, truthfully, is dietary sugar. So you can’t see it because it’s all packed away in the liver. The liver is the main organ to be concerned about. It’s the fatty liver that causes a lot of type two diabetes and it really holds the key to it. And this is one thing that you have to understand is that you can exercise all you want, but you can’t exercise your liver.


You’re exercising your muscles, tendons are going to improve but your liver is not going to improve. Yes, you’re going to burn some calories doing exercise and you’re not going to get rid of the fat inside that liver. And fructose, which is part of the glucose and part of the sugar sucrose, is really the main culprit in that. So you actually see this very close correlation between intake sugar, for example, and the rise of type two diabetes. So it’s most clear in places like China, for example, in the 1990s, they had very high mortality, they were all eating white rice and everybody says it was brown rice.


That’s crap. I mean, I have relatives who lived in the area and they all eat white rice. And then all they’re eating lots of white rice and there’s practically no diabetes whatsoever. And the issue is that almost no sugar. So sugar with its fructose, high fructose, corn syrup, and table sugar are much worse than carbohydrates like bread, glucose causing type two diabetes because that fructose, kind of, goes straight into the liver and causes that fatty liver. So athletes, perversely, are at fairly high risk because they’re drinking all this Gatorade, especially the older ones that grew up in that era of Gatorade and Powerade and all those kinds of sugary drinks. And they all thought it was fine to drink the sugary beverage and exercise, burn it all off. But the problem is that you’re burning off the glucose but the fructose went into your liver. You got fatty liver. And then years later, despite the fact that you’re exercising like crazy, you’re getting all this type two diabetes, In China what happened is that their sugar intake has been rising very quickly as they sort of westernize their diet and combine with their original high carbohydrate intake. What’s happened is not an explosion of type two diabetes and went from approximately 1% in 1980 to approximately 11.4%.


I think that’s a huge, huge ’n’ times rise in type two diabetes in a single generation. And this is what’s scary about the whole thing, is that everything that’s happened has happened since about 1980. If you ever look at old pictures from the 70s and you look at the people on the street, it’s shocking because people are so thin. It’s ridiculous!. And everybody wants to say, well, “it’s genetics, it’s genetics”. It’s not genetics! In a single generation, the genetic pool has not changed very much. It’s time to sort of admit that this is a dietary problem. And what is it that we had changed in our diet that has made us so poor and that’s where we really can educate people and then help them to take control on their own? 


So, there’s a couple of things. When you think about type two diabetes, what it is, is essentially too much sugar. And not everybody wants to make it more complicated. It’s not really! So sugar is composed of both glucose and fructose. So glucose is a sugar contained in most carbohydrates and bread and rice. If you have table sugar or high fructose corn syrup, which is very similar, you have one glucose and one fructose. The difference between glucose and fructose is that all cells of your body are able to use that glucose. So if you eat a pound of sugar, you get half a pound of glucose and half a pound of fructose. 

The glucose is used by your entire body. So all the cells, all the muscles, all the liver, all the kidneys, the brain, they all use it and they burn it off. Fructose, though, can’t be used by any cell in the body and heads straight into the liver. So, therefore, what happens is that fructose goes straight into the liver. And because you don’t need the extra energy, because you have all this glucose, it just gets turned into fat. And that’s where you get the fatty liver.


The fatty liver is really where the kind of diabetes starts. If you want to think about what insulin resistance is –  so you hear this term quite a bit, which is inconsistent –  and what it means is that insulin is a normal hormone, that when you eat, your insulin tends to go up and that tells the body that food is coming. So you open up the cells so that they can take on some of the food energy and use it for energy.


And you start and you don’t burn your stored energy. The food is coming and the insulin is going up. Your stored food energy and your body is using the glucose that’s coming in. Insulin resistance refers to the fact that when people eat, their blood glucose, which should stay normal as the glucose goes into the cell, starts to go up. And that’s when you check your blood sugar, for example, and it’s high. Your doctor tells you that you have type 2 diabetes. And the reason they say that it’s insulin resistance is because of you measure insulin levels – it’s not low! It’s actually very high. So, there is plenty of insulin but that insulin is not able to force the glucose from your blood into the cells. So, that’s what is called insulin resistance. And they are essentially synonymous – type two diabetes is insulin resistance and insulin resistance is type two diabetes. They just kind of fall along the stack, that is if you have mild insulin resistance then you may not qualify for type two diabetes, but they’re essentially the same. And for many years people tried to say, well, what’s causing this insulin resistance? And one of the things is that they had this sort of lock and key model where they said, well, there is something that’s blocking the insulin from opening up the cells and letting the glucose go inside. That didn’t really work out. What it really is, a sort of overflow. That is if your cells are already jammed full of sugar, and now you eat, your insulin goes up, you’re trying to jam the sugar into this already filled cell. So it’s not going to go in. That’s why you are insulin resistant because it’s already full. It’s not that the insulin is not working. It’s working, but you can’t shove it in. So if you want to imagine, like a suitcase, when you’re putting clothes into an empty suitcase, goes in no problem. If that suitcase is already full, you can’t jam in those last two pair of pants because it’s already full. So there’s nothing wrong with the pants. Nothing wrong with the suitcase. It’s just full. So that’s what causes insulin resistance. 


So, think of our body as a sugar bowl. So if we start out with the Sugar Bowl empty then over time you put some sugar in. You burn some sugar when you don’t eat and you put it in when you do. If you’re putting in more sugar than taking out, over time, that bowl fills up. Now, if it’s completely filled, the next time you eat, the sugar just spills out into the blood. What your body does is  “Woah! I see all this sugar in the blood and I don’t like it and all this glucose. I’m going to produce more insulin to really shove it in.”


So, now you’re using more insulin to shove the glucose into a cell that’s already filled with glucose. That’s what happens. And it compensates over time. At first, your blood glucose stays normal but only because you’re producing so much insulin. If you think about the suitcase, what’s happening is that you’re just using a lot of force to jam close that suitcase. Eventually, it comes to the point where the body is completely filled up and it can’t take anymore. So your blood glucose goes up. What does your doctor do?


You go to your doctor, he gives you warrants,. Insulin was already high!  Insulin was a problem in the first place. So it just keeps shoving in more glucose and, in over time, your body just keeps filling up more and more with this sugar. And it goes initially to the liver, but the liver sends it out all over the body. It packages as fat because the liver has the ability to turn that carbohydrate glucose into fat. it is called de novo lipogenesis. If you have too much glucose, the body turns that into fat. Sends that fat all over the place. You get fat in the liver, you get fatty pancreas, you get fat in the muscles, you get fat around the organs, you get the abdominal obesity where all the fat gets stored around the organs and you get a very high waist size. What you see is this kind of big beer belly that people notice, even if the skin is not fat and even if the arms are not very fat. So that’s the real problem is that the bottom line was that there’s just too much sugar, not in your blood, but in your whole body.


And this is the mistake that we made. We have been using drugs, like insulin, to take the sugar out of the blood and jam it into our bodies. And our bodies didn’t want it. It took it, but eventually it developed more resistant. So then you have to use higher and higher doses. And you’re using higher and higher doses of medications then your diabetes is getting worse. So the answer is not to do that. The answer is obviously, if your body has too much of this sugar, just empty the body of the sugar.


So when I tell people, it’s well, think about your car. If you have a car and you fill up with gas and your gas tank is full, you still need to put some more gas in. So you’re forced to pump this gas into your back seat. Well, what would you do? Well, you wouldn’t just go to the gas station three times a day and keep pumping gas into your back seat. You say that’s really stupid. What you need to do is, one, stop putting gas in and, two, drive that car and burn it off.


So if you understand that the whole problem is just too much sugar – both glucose and fructose – then one, you cut down the glucose and fructose. So that’s why we say cut down the refined carbohydrates, cut down the fructose. And two, if you want to burn it off, the key is intermittent fasting. Everybody thinks that it’s exercise, but again, it’s liver that’s the problem. It’s the liver that’s getting too much glucose that’s now packaging the new fat and sending this all over the body. 


So you need to so-called “exercise that liver”, which is by not eating. And guess what? It’s a complete natural process. There’s no drugs involved, there’s no surgery involved. You can start doing it tomorrow if you want to, and it’s completely free. None of this is easy. Like, it’s simple. The concept is simple, “let’s actually do it”  – is not that simple because you all get hungry. We all want to eat cake. It’s normal. That’s not, you know, a defect. That’s just makes us what we are.


So there are things that we do need to do. One is sort of provide support for people to do the fasting. To keep the low carbohydrate diet, we have to do good recipes and make it acceptable, because the thing is that something like intermittent fasting is not well accepted at all. There’s a lot of myths surrounding it.

And that was one of the things that I tried to address in my second book, which was the “Guide to Fasting” was a lot of these myths that fasting is bad for you, your going to shut down your metabolism, you’re going to burn through muscle.


A lot of these myths that are not true. And the truth is that fasting has been used for thousands and thousands of years and it’s been used safely. Every religious group uses it and it gets couched in different terms, whether it’s a purification or a cleansing or a detox. The essential idea is that by not eating, you’re allowing your body to clean itself out, all the junk that’s making it sick, which is all that glucose and all that fat and the liver.


And guess what? It actually turns out to be true. But there’s a lot that goes into it. So making it socially acceptable, because one of the big mistakes that people do when they fast, like they tell their doctor, they tell the dietitian or they tell their friend and the friend, who doesn’t know, but is trying to be helpful, “Oh, you can’t do that. You should never do that.” It’s like, well, what, you have a three hundred pound person with the most severe type two diabetes and you think they can’t miss a single meal.


What do you think’s going to happen? It’s interesting because when I talk to doctors and I do give a number of lectures, doctors almost immediately understand that there is nothing wrong with fasting. That is, we tell people to fast all the time. When you go for colonoscopy you fast. When you go for surgery, you have to fast. When you have the blood work, you have to fast. And we all know that as doctors, when we were doing a medical residency, medical school, we fasted all the time because we were just so busy that you didn’t have time to eat and you just work right through it.


That was just the way life was. And if you’re busy with work, that’s it. It’s not like you’re going to die or something. And if you look around the animal kingdom, for example, or you see bears that are going six months hibernating, so no food. You see lions that eat once a month and snakes that eat once a month. So you know what? Guess what? That’s the reason our body stores fat. It’s for us to use when there’s no food to eat. If you are always eating, why would your body burn off that fat? That’s its stored energy. So it’s going to hold on to it. What you have to do is give your body the time to try to burn off that fat, that is making us sick. So doctors almost immediately understand that there’s actually nothing intrinsically wrong. But you do have to use some common sense. That is, not everybody should fast. Pregnant women shouldn’t fast Children should not fast. And if you’re malnourished you shouldn’t fast., If you’re on medications, you need to get some medical advice as to what to do with those medications, especially for diabetes medicines if you fast and take the same dose of medication, you put yourself at real risk. But getting back to the question of what we need to do, we have to make it socially acceptable. We have to put in the support structures that the doctors aren’t there to support patients. We have support groups for that. And this is one of the things that I sort of learnt from trial and error over these last 4 -5 years or so. In the last four or five years, we developed this program called the Intensive Dietary Management Program, the website, IDM program, dot com.

And what we do is try and provide that support. We give a counsellor who is able to help people with fasting because there’s not a lot of knowledge about that. We can help them with problems that come up during fasting because again, it’s not fun and it’s not easy to stick to. And we provide. We do small group sessions because that peer support is actually very important .In school, of course, we talk about peer pressure. That is, even if the teacher tells you to do one thing, you may not do it if all your friends are doing something else. So it’s very important to get the support of your peers to do something, and we want to harness that for the good. So we put people in small groups and they’re all trying to do the same thing. They’re all trying to lose weight. They’re all trying to reverse their type two diabetes. So there’s great support in that. And groups like ‘Weight Watchers’, groups like ‘Alcoholics Anonymous’ have figured that out a long time ago. It took me a while to figure out, but eventually I realised that small groups are actually one of the real keys to successfully treat these patients.


So you have to have the counsellor who knows how to help people, like headaches come up with constipation, diarrhoea. You have to have somebody who’s done it, who knows what they’re doing. You have to have the peer support and you have to have the medical support from your physician. And that’s the sort of program that we’ve tried to put together, in this IDM program. And over the last few years, it’s been really very rewarding because it’s it’s incredible to talk to people.


And this morning I had a group of four people and all four of them had virtually reversed their type two diabetes. One was on like 45 of insulin, one was on 180, one was on 95 units of insulin, and all had basically become pre diabetic on that thing. And it’s really incredible to talk to them because it’s the reason that we all went into medicine. We didn’t go into medicine to prescribe pills and watch people go on dialysis and get their feet chopped off.


We went into medicine because we wanted to make people better. In here, I see people in front of me who had reversed their type two diabetes, something that their own doctors had told them wasn’t possible. And it’s like, wow, that really makes me feel good and it makes them feel good. So it’s great. It’s a win-win situation. The government saves money because it’s not paying for all these drugs. It’s not paying for all these heart attacks and strokes and kidney failure.


They don’t want it anyway. And hey, everything just comes down to applying the right knowledge. I’m not talking about building great surgical centers. I’m just talking about spreading knowledge to the people who need it and then putting in the supports for them to actually do well. So we have a fasting support group, but there are ones online that you can join for free. You can read the books. They’re very inexpensive. You can read the blog for free.

You can go on to great websites like “dietdoctor.com”, which has great recipes. There’s a UK website which has a free low carb program called “diabetes.co.uk“, and of course, stuff like Youtube feed, which is promoting healthy diets for people to reverse their disease. And it’s like this is amazing that we can do this for people without building brick hospitals and incurring huge expenses and so on. It really, kind of, reinvigorated my sort of passion for medicine.


The first question was about this sort of myth that’s been around and you hear it from even the authority figures like dieticians and doctors that the brain needs 130 grams of glucose in order to function properly. And the idea is that you need to eat 130 grams of glucose to function properly. And those are two completely different things. That is, if you need 130 grams of glucose for your brain to function, you’ve got it stored in your liver. It’s called glycogen.


Glycogen is the stored form of sugar. The body takes the glucose that you eat from lunch. It stacks them all together and puts it in the liver in the form of glycogen. So in plants they use starch. So potatoes are from starch. But if you look at what starch actually is, it’s a big, long chains of glucose. So the same thing happens with liver. The animals now don’t use starch, which is animal leptin. We use glycogen. So it gets stored in the liver.


So, if you don’t eat for 24 hours, your body simply takes that stored sugar and breaks it down. After that, what happens is that the body starts to burn fat and it still needs a little bit of glucose. But what it does is that it creates new glucose in a process called “gluconeogenesis”. So ‘gluco’ means glucose, ‘neo’ means new and ‘genesis’ is to make. So gluconeogenesis is making new sugar from those fat. So you can take the glycerol backbone. You take off the fatty acids, your body burns the fat, you take the glycerol, you change it into glucose and you send it up to the brain.


Your body also produces ketone bodies, which is from the fat. And that is because the fat cannot cross the blood brain barrier and your brain can’t use the fat. Your muscles, for example, can burn fat directly, as can your liver, as in most of the other tissues of your body. The only parts of your body that need to still have some glucose is the brain and certain small parts like the red blood cells. So what your body does is it takes the fat, produces ketone bodies, which will now supply up to 75% of the brain’s energy needs and the rest of the glucose, that you need, for the brain to function derived from the fat from gluconeogenesis and some protein breakdown.


So that’s how your body survives when you’re fat. And again, this is completely normal. We have people who have fasted for a week or two weeks at a time and we have like 75 year olds who do this and they feel completely normal. In fact, one of the very interesting things is that the brain seems to work better in the fasted state. That is, there’s a lot of research that shows that when you fast people and then do things like memory tests, their memory is better.


There’s maybe prevention of Alzheimer’s disease. They seem to function better using those ketones as opposed to just straight glucose. So while it’s possibly true that your brain needs 130 grams of carbohydrates to function. It’s not the same as you must eat 130 grams carbohydrate because, for example, we will have people who will turn out to fast for 24 – 48 hours to do a colonoscopy. Remember, colonoscopy is a routine procedure now. It’s done in everybody over the age of 55. So people are fasting for 24 hours. None of them turn into stark raving lunatics because the brain doesn’t have enough glucose. They would be a little hungry but otherwise completely normal. So there is this entire myth that has gone around saying you must eat 130 grams of carbohydrates each and every day. Otherwise, you’re going to die! No, that’s not the case. Your body has a storage form of energy, that glycogen, and it will use that.


That’s just like saying, “Oh, well, you spend fifty dollars every day. So you must go out and earn fifty dollars every day.” And one day on a weekend you decide to take it off or you can die. You store money to use when you’re not working. Your body stores food energy for when you’re not eating. That’s the only reason we’re all still here. Otherwise this would be like Planet of the Apes or something. It’s ridiculous.


Type one diabetes is a completely different disease. And one of the important things that we recognise in the last little while, is that a lot of older people also develop type one diabetes. So sometimes people call it late onset type one diabetes. So in the old days, it was always in children. So you’d see these 10 year old children and they would have diabetes. And it’s all type one diabetes. Now you can see type one diabetes in a 65 year old person and it’s not all that unusual anymore.


And why it’s increasing in prevalence? The difference with type one diabetes is they’re essentially as opposites. One has too much insulin, which is type two diabetes. Type one diabetes is too little, and that is, there is an autoimmune destruction. Your body’s own immune system, for some reason, destroys the pancreatic cells that produce insulin. So there’s really just no evidence that glucose cannot go into the cells. And what happens is that because it can’t get into the cells, you pee it out and people just start to lose weight like crazy.


So this 10 year old children, they would be skeletally thin. You never see pictures of an untreated type one diabetes. They were skin and bones. And then they would die because the insulin would not let them use any of that energy. So when you give them, it’s fine. The problem is with type one diabetes and if you take too much insulin, then you run into problems over many decades of too much insulin. So if you have too much insulin, you gain weight and you develop insulin resistance.


So what you see clinically is that type one diabetes, after 15 – 20 years, they start to gain weight and their insulin dosage starts to go up. Instead of using 15 minutes a day, they start using 20 to 30, 40, 50. So their bodies are becoming insulin resistant and, again, insulin resistance is caused because of too much insulin. You’re stuffing too much sugar into those cells. So the point is that there’s two main problems. One is type one diabetes. If you have very high blood glucose, that’s problem.


And two, over the long term, having too much insulin is also a problem. So the way to manage that, you want to minimise the blood sugars and you want to minimise its dosage. And the best way to do that is to use a low carbohydrate diet. And that is if you don’t take low carbohydrate, you don’t put a lot of demand on your body to have more insulin. That is, if you think about a cookie versus an egg, if you eat that cookie, your blood glucose goes up, you need insulin to cover that.


If you eat that egg, same calories, your blood glucose did not go up and you don’t need insulin to cover that up. So you can get the same nutrition, you can get the same calories, but one will require a lot of insulin and one will require very little. So if you eat more fatty foods, natural fats, low carbohydrate, you’re not going to put the requirement on body to make insulin and therefore you can minimise the insulin dosage and, over the long term, have less weight gain, have less insulin resistance, which causes all the other problems, heart attacks, strokes and so on. But, yes, type one diabetes is actually, a sort of, untreatable kind of disease. You can manage it, you don’t want to go overboard on getting treated and otherwise eventually the problem is too much insulin. The problem with calories is that the body has no way of measuring calories. So it doesn’t matter if you eat a cookie, say 100 calories versus 100 calories of a kale salad. It’s the same number of calories and body has no way of knowing. The way the body works is that it responds to hormones. Hormones are chemical messengers that tell the body what to do.


So the question is not as a calorie, of course, a calorie is a calorie. The question is, are all calories equally fattening? That’s the real question. And it’s not at all clear that the answer is they are. In fact, it’s all very different. As soon as you put that cookie in your mouth, hormonal response of your body is completely different than eating that kale salad. Same calories – completely different hormonal response. That is, you eat the cookie and then insulin goes up. Way up! You eat that egg and kale salad, insulin doesn’t really go up very much. You don’t starve as much. If you don’t starve your body, then it burns. So it’s not that there’s this, sort of, magical calorie counter in the body that counts all your calories, tally’s it up at the end of the day and sort of rings a bell. It’s really the body relies on hormone signals. So what you have to understand is that obesity is not a caloric imbalance. It’s a hormonal imbalance. Know, the main hormone is insulin, but there are others, cortisol, for example.


And if you understand that the problem with obesity is that insulin is too hot and the answer is simple – lower insulin. And the question is how do you lower your insulin? Low carbohydrate diets and you do fasting. That’s how you lower the insulin. If you thought that obesity is because of too many calories, then the answer is just cut the calories. And that’s what we’ve tried that and it hasn’t worked. As I mentioned, the failure rate is like 95% . And one of the things that’s really super unfair to me is that we keep blaming the victims for their obesity.


That is, we give them a diet that has a 99% failure rate. Then when they fail, we turn around and we blame them. “Oh, you didn’t have enough willpower.” “Oh, you just didn’t follow our advice.” “Oh, you let yourself go.” That’s so unfair. These are the victims. Yet we’re trying to put the blame on them because the sort of nutrition authorities, all these kind of academic doctors and researchers can’t admit that their advice is not good.


So they have to blame the patients. They can shift that blame onto the patients. And the patients actually believe that they are the ones at fault. And that is really unfair thing that we’ve done to people. And of course, people just give up because they thought, well, it doesn’t work, so I’m not going to do it. So, you know, it’s very empowering to people to really understand their obesity, take control of type two diabetes and be able to do something about it. If it’s too much insulin then lower the insulin or if it’s about too much sugar then lower the sugar in the body. Don’t make it more complicated than it already is.

It’s crazy that we would have these people that say, “Oh, you have to eat breakfast!”, like you can eat breakfast even if you’re not hungry. “Oh, just shove a muffin at your mouth.” How is that going to make your obesity or type two diabetes better? Can somebody please answer that question for me, because I am mystified at how shoving a muffin in your mouth is going to make you more healthy than if you just say, “Oh, I’ll just have some tea and wait till lunchtime.” It doesn’t make any sense to me. Unfortunately, that seems to be a lot of nutritional science. 


What is it that I’m going to do to leave this world a better place? Because that’s passion. I mean, really, passion is the key and it really is something that you get as you get older. My younger days, of course, you’re worried about what you’re going to do, your career, how you’re going to make money, who you’re going to marry and all of that. But once you hit, kind of, the middle age then you start to think, “Well, I’m not going to live forever. How am I going to make this world a better place? How are people going to remember me? What’s going to be my legacy?”  and really that sort of an overwhelming sort of passion in life, and it really is what gives life meaning because it’s not enough to make a good living and have a roof over your head. I mean, those are all important things to happen. But if you do have them, then what you want to do is pay it forward to give it back. 


To me, that passion is, really, what is sustaining me. I do this not because it makes me money, but it’s really the passion that’s really important. What are you going to do to help people, to pay it forward to make life better for everybody else around you? I don’t have two diabetes. I don’t have to worry about it. But I see other people. I see lots of people. And I want them to think, wow, I want to be able to share that knowledge and be able to make them better and healthier and happier.


And that’s really what is important.The passion, your mission in life, what it is that you do. I think that really is to me, one of the most important things that’s driving. And it really is one of the most fulfilling things that you can do; is to do it for somebody else. And you realise that sometimes when you have children, that is when you’re a child, you enjoy a lot of things like Christmas. After a while, you can buy everything that you need and Christmas isn’t as exciting.


But then when you have a child, that excitement just kind of explodes again because you see the happiness.You see it and you’re able to give it to somebody else. It’s an amazing feeling and it’s the same thing that I want to be able to do. So I think passion is really the most important thing, I would say. Find your passion and do it, whether it is making the world a better place or whether it’s helping people do it, because it is just the most thrilling thing.


As you said, when people come back and email me or tell me all “Wow! It’s amazing that I have found you online. I was able to get better.” Great! I haven’t profited in any sort of financial way. But in a spiritual way, I’m so much richer for that entire experience. And that’s what drives all of us. Really, all of us in this community is this, sort of, shared passion, shared dream of something that just means we’re all in this, sort of, world together and we should do what we can to make each other better.

You know, the food that you eat and sleep and all of those things are very important as well. And our community is probably one of the least understood forces of wellness, but it’s actually one of the most important to look at. Blue zones, for example, why people in these blue zones are so much healthier? Not necessarily the food or the exercise, whenever, it’s actually the sense of belonging and sense of community that they have. And that’s something that’s very under-appreciated by sort of Western medicine, which is sort of a blood work-driven, sort of X-ray driven, sort of, specialty. If you can’t quantify it, it’s not important. But the sense of belonging, a sense of community which goes along, you find it when you find your passion in life and what you want to do.

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