Dr. Jason Fung is a nephrologist and worldwide expert in intermittent fasting. Based in Toronto, he graduated medical school in internal medicine at the University of Toronto prior to finishing his nephrology fellowship at the University of California – Los Angeles. Dr. Fung has published several books about weight-loss and intermittent fasting, including The Complete Guide to Fasting.
On today’s episode of The Low Carb Leader Podcast, Dan chats with Dr. Fung about what intermittent fasting is and why it’s better for your health than you may think. He explains how the body actually works – on a mental and biological level – during a fasting period, as well as how the benefits and risks compare to traditional calorie restricted diets.
“If you have a plate of brownies, or if you have a salad with salmon, they could be the same number of calories – but what they do to your body is completely different.” – Dr. Jason Fung
On Today’s Episode of the Low Carb Leader:
- What is intermittent fasting?
- How diseases today are all related to nutrition.
- The hormonal response differences between the types of food you eat.
- The benefits of intermittent fasting.
- Why calorie restriction diets often fail and how it is different than fasting.
- The mental effects of intermittent fasting.
- What to expect when you start fasting for the first time.
- What is autophagy and how it helps your body rebuild damaged cells.
- All calories are not equal.
- The breakdown process is just as important as the rebuilding process.
Connect with Dr. Jason Fung:
- The Complete Guide to Fasting by Dr. Jason Fung
- The Obesity Code: Unlocking the Secrets of Weight Loss by Dr. Jason Fung
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Read Podcast Transcript
024 – Intermittent Fasting with Dr. Jason Fung, Part 1
Hello, and welcome to The Low Carb Leader podcast. I’m your host, Dan Perryman, and you have joined me for Episode 24. Today we have an awesome interview with Dr. Jason Fung. I interviewed Dr. Fung in Breckenridge, Colorado, this past weekend at the Low Carb Breckenridge conference. We actually did a Facebook Live interview, which was very informative. And Dr. Fung is a worldwide expert on intermittent fasting and a skilled physician, just a great guy.
A little bit about Dr. Fung. He is a Toronto-based nephrologist. He completed medical school in internal medicine at the University of Toronto before finishing his nephrology fellowship at the University of California Los Angeles. He then joined Scarborough General Hospital in 2001 where he continues to practice. He is the author of several books, including The Obesity Code: Unlocking the Secrets of Weight Loss and The Complete Guide to Fasting.
Low Carb Breckenridge Conference in Review
So before we get into the interview I just want to discuss the Low Carb Breckenridge conference that I just returned from last night. This was an amazing weekend. They brought in numerous speakers, top speakers in the field of diabetes, low-carb. There were physicians, clinicians, just a great panel. So the whole weekend was lectures and networking. There was about 300 people there. And so what was really cool about it was you could interact with the speakers and get to know a lot of people. So as a result, Dr. Fung, we did a Facebook Live interview, talked with him all weekend. Also did a Facebook Live with Maria Emmerich who is the author of nine books on ketogenic cooking, and she does a lot of nutritional consulting. And if you listen to the podcast I had already interviewed her, but we wanted to do a Facebook Live, which was really cool.
So just wanted to talk about Breckenridge. For those of you who are skiers or those of you who have been in higher altitudes, Breckenridge was at 9600 feet, and I never realized what altitude does to us, and so a lot of people, including myself, kind of went through the whole weekend with headaches and cramps in our legs. And I talked to quite a few people at the conference, and everybody was kind of experiencing this altitude sickness because that’s pretty high, almost 10,000 feet. And so they had an oxygen bar there where you could sit in there and breathe oxygen. Of course you pay for it. I did that for a couple days actually, 45 minutes a day, and that made a big difference. So never really knew how altitude affected me because I’ve really never spent three days at 10,000 feet, and then knowing that the skiers were up at around 13,000 feet. And it was extremely cold, so the wind chill was definitely below zero. But if you look at the Facebook page, The Low Carb Leader, you can see pictures. Beautiful place and an amazing conference. So happy that I went.
Just want to remind you that I will be kicking off the 14 day Tabata challenge on March 15th, and so if you signed up you have received the first email and you’ll start getting more emails as we go. We have 550 people who have confirmed, and actually 850 people who have signed up. So you have to confirm on your email. So please go to your email and click on it.
So we’ll get on to part one. The reason I broke it up is because we talked for over an hour, and it would make the podcast episode a little bit too long. So part two will be coming out soon. Hope you enjoy the interview.
Dr. Fung’s Medical Background
So where I kind of switched a little bit from kind of conventional medicine was somewhere around 2011, somewhere around there when it kind of became obvious that nutrition was really a very, very more important part of medicine than most conventional doctors are trained to understand. So that’s when I started really looking into weight loss, obesity, type II diabetes, and really realizing that a lot of what we get taught is not actually true, which is funny to say. The sort of root cause of much of our disease, type II diabetes with all of its downstream complications, heart disease, cancer, kidney disease, which is where I come in, but also blindness, amputations, Alzheimer’s disease, all of this which practically takes up like 50% of our healthcare dollars is all related back to nutrition and weight and so on, and nobody even really seems to care too much about it other than eat a little bit less, portion control, count your calories, exercise. It’s like well that’s really tired advice. I mean I got that advice in the ‘80s when I grew up, and it’s the same advice we give people now, and it hasn’t worked. So this is where I came in to see the real sort of fallacy, the sort of illogic of what we do. But unfortunately it’s such a big part of healthcare that we really can’t sit by idly and just let it go.
Yeah. I mean you know I work in a hospital, and doctors are not trained on this, are they?
Not at all.
And I don’t think people understand that, but I read you maybe go through one nutrition course.
Yeah, so honestly I don’t remember any of them. But I’m sure I had them. So out of four years of medical school we had probably seven or eight hours of nutrition, but it wasn’t really truly nutrition. You’d go over biochemical pathways of vitamin K, for example. So that was your nutrition course. So we’d learn all these pathways of vitamin K, which relates to anticoagulation. So again, relating back to medicines that we’d give people, not really what people should eat and how they should stay healthy and how to lose weight and that sort of thing. The stuff that everybody assumes doctors understand, there is practically zero training. So there’s a lot on other things about nutrition which relate to disease, beriberi disease, scurvy, like nutrient deficiencies and so on. But not a lot on what affects you and I and the rest of North America because we don’t treat beriberi disease truly, right? It’s not a very common disease compared to obesity and type II diabetes, for example.
So really in truth there is zero nutrition courses. So then after the four years of medical school then you go into what I did, which was internal medicine, which is five years of postgraduate training. So it’s a lot of training. And in there there is truly zero hours of nutrition unless you’re interested. So out of nine years of medical school and postgraduate training you get virtually zero on how to lose weight, how to treat your diabetes. So really that’s what’s happened. So doctors have been kind of – they don’t get the training, so they leave it to other people to deal with. So you leave it to the dietitians. And in truth where do people get their weight loss advice from? They have to go to Weight Watchers, or they go online and they follow some guy who sells them all kinds of stuff. There’s all kinds of stuff out there.
So we are live. This is, for those watching right now, this is the first time that I’ve ever done the live thing, and my contacts don’t work so well, so I’m actually going to have to move up just to see what – if you have any questions or comments for Dr. Fung let us know. But we do want to talk about intermittent fasting. So you go around the world, pretty much, and I’ve watched a lot of your YouTube videos. You know you have like 100,000 viewers when you have a YouTube video.
Which is pretty awesome, which kind of shows that people are really interested in this concept of intermittent fasting. So for those that aren’t familiar with it, what would – just kind of a background.
What is Intermittent Fasting?
Intermittent fasting is basically where you don’t eat. So you can drink water, and there’s all variations. You can drink teas and coffees in some, and some people allow broth, and some people allow [inaudible 0:08:48.2]. But they’re all variations of a prescribed period of time that you don’t eat. And it can be any period of time. So it’s infinitely flexible. So it could be 16 hours; it could be 24 hours; it could be 36 hours. It could be five days; it could be seven days; it could be 30 days. So you can do anything you like or whatever suits you. And the thing about the way I got into this kind of field is actually very strange because I started out looking at weight loss and obesity and understanding that what we get taught, which is it’s all about calories, is really not true.
All Calories are not Created Equal
So this is what everybody thinks is that if you eat too many calories you gain weight with no kind of differentiation of where those calories come from. And that sort of idea has been promoted a lot, mostly through commercial interests, to try and convince you that all calories are the same. But they’re not. It’s so obvious that if you have dinner and you have a plate of brownies or if you have a salad with salmon they could be the same number of calories, but what they do to your body is completely different. And as soon as that food goes in your mouth the hormonal response of your body is completely different. And that’s the point. One will cause a lot of insulin release and weight gain. The other won’t. So why we pretend they’re equal, I don’t really know. I think it’s because a lot of the people who sell junk food, sell sugary sodas, have always tried to promote that message that all calories are equal. But they’re not. They’re all different.
So that’s how I started. I started doing a low carbohydrate sort of a clinic, and the thing was that it was a total disaster. Nobody was doing what I was telling them to do. And it wasn’t – so then I had to kind of go back and say why aren’t people understanding this? And it’s hard because we’ve been trained for 30 years, 40 years, to eat low-fat, cut your fat, count your calories. And they couldn’t really get their heads around that all this rice and all this pasta and all these sugary drinks, you know, they don’t understand what it was that I was trying to tell them.
So that’s when I thought well I really have to do something a little different here. Because if you’re very interested, if you’re 30 years old and you’re on the Internet all day looking at nutrition lectures, yeah, you’ll understand what I’m talking about. But that’s not my patient. My patient was 65, 70 years old. Maybe they were Filipino. Maybe they were Chinese. Maybe they didn’t speak English. Maybe they’re Arab. There are so many different people, and it really didn’t work, that low-carb. They’d have all different ideas of what it was. So then I thought well, okay, then I have to do something else.
So that’s when somebody had mentioned one of these cleanses that they were doing, and I thought well that’s just like fasting. I thought what a terrible idea. Fasting is just a terrible idea. That’s my initial thought. And that’s what almost everybody else, when I mention it, thinks. But again, my advantage is that I understand physiology, and I have the resources to look it up. And I thought well, my initial reaction, my gut reaction is that this is such a terrible thing, but why do I think that? What is really going to happen if people don’t eat? And there is a couple of things that I kind of always thought was interesting. One is that as a doctor I tell people to fast all the time, and it’s not because of nutrition; it’s because they’re going for surgery, they’re getting blood work done, they’re getting an ultrasound done, they have to get this test done, they have to get endoscopy, colonoscopy.
So for example if you have people do a colonoscopy, which is now routine after age 55, there are places that make you fast for two days. And guess what. Nothing bad happens in those two days, and I always remember back when I actually had an endoscopy – it’s funny because I had two gastroscopies when I was a kid because I had peptic ulcer disease. And I fasted for the endoscopy because you have to clear out the gut. And I remember this is not that bad. Like I didn’t eat for 24 hours because that was the standard at the time, and I felt really normal. I thought I wonder why that is. And so I always remembered that.
The Safety and Simplicity of Fasting
So that’s why I went back and thought we tell people to fast all the time. And the other thing that I always thought was very interesting was that when we get people out of the intensive care unit onto my medical floor they might have gone into the intensive care unit taking 200 units of insulin a day. When they come out, because they’ve been sick and they haven’t been eating, they are off all their insulin, and their blood sugars are perfectly normal. I thought that is weird, and I saw it for 20 years, but I didn’t kind of put it together until I really started to think about it. I thought, well what really is wrong with fasting?
So then I went back and I looked at all the data on fasting, what happens physiologically to the body, and guess what, nothing bad happens. You store food energy as fat and glycogen, and when you don’t eat you just pull it back out of your body and use it. That’s the way we’re designed. And then you think back, okay well there are so many historical things that we’ve done with fasting that is through religion, and it’s not one religion. It’s all religions. But even if you go back even further to the kind of beginning of human history people didn’t eat for long periods of time because there was no food. And guess what. We’re here. So they survived. Those cavemen survived.
So that’s when I started thinking okay, well the fasting is actually a very interesting idea because one, because of that link to all, basically all of humanity, every religion in the world has prescribed periods of fasting, everybody kind of understands what fasting actually means, whether it’s because we tell them to do fasting blood work and all this sort of thing. People understand what fasting actually means. And three, it’s conceptually very simple for them to understand that if they don’t eat that blood sugar is going to come down. If that blood sugar comes down they don’t need to take insulin or as much insulin or their medications, and guess what; they’re going to lose weight, too.
So because it’s so easy for people to understand, there’s a much higher rate of acceptance, whereas if you tell people well you should eat low-carbohydrate, high-fat, they’re like whoa, high-fat? The last 40 years every doctor has told me to eat low-fat. Now obviously that has changed, but some people haven’t kind of caught on to that switch that we’ve kind of cut out a lot of that from the dietary guidelines for Americans. They cut that kind of total fat cap out of it. The Mediterranean diet is not a low-fat diet. It’s a high-fat diet with all the olive oil, avocados and nuts. So we are moving towards more and more kind of healthy fats. But a lot of people don’t understand that. They don’t keep up with it. But fasting, they understand. It’s like hey, this is what I need to do. They understand exactly why it’s going to make them healthier, and they understand exactly what they have to do because it’s not like eat this and not that, and this and not that, and this and not that. It’s like duh, just don’t eat anything at all. Just drink water for this period of time, and that’s it.
And the other advantage is because I could prescribe those periods of time, I could adjust those medications exactly to what that period of time was. And this is a big advantage. So it’s a huge advantage when people are changing their diet because of course their insulin doses, their medications, are based on what diet they’re eating. So if I can control exactly the diet, I can prescribe them and have them do it safely. So that’s a huge advantage, and there are so many other advantages. It doesn’t cost them any money.
Yeah, that’s a great –
Huge advantage. They understood what they’re doing. They could easily explain to their family members what it was that they were doing, and again, I have a huge advantage because then they can say oh, my doctor told me to do it, whereas if somebody else does it and says oh I found this on the Internet somewhere that somebody told me to do this, their family would be like oh my God, don’t do that. But then they’re like my doctor’s doing it. He’s monitoring my blood work. He’s monitoring me. He’s monitoring everything, like my medication. So they feel safe.
It gives it legitimacy around it.
We do have a couple – let’s see if there is a – [Healy 0:17:05.1] watching from the Pueblo of Zuni in New Mexico – that’s awesome – and Denise watching from Texas, well welcome. That’s cool. So I’ve experimented a lot with intermittent fasting, and so I’ve done the 16/8 window where you eat for eight hours, and I’ve been really watching – I did a five-day water fast and measured glucose and ketones and the ratio. But what I found was when I eat in a bigger window I lose my level of ketones over a few days a lot quicker, and my blood sugar actually goes up a little bit. So what I’ve been doing is closing that window. So now I’ll eat from like 2 to 6, and I’ll drink bulletproof coffee. I’m addicted to that stuff anymore. But my blood sugar has dropped, my ketones – so the caloric restriction is a big part of ketones and blood sugar, right?
How Fasting Helps the Body Switch Fuel Sources
Yeah, and this is the thing that people don’t quite understand. This whole thing about calories and calories I’d say is quite a useless concept because, for example, if you simply restrict your calories, which we’ve always told people to do, if you say to somebody okay you normally eat 2000 calories a day. Now you cut it to 1500 a day. Every day you still eat three, four, five meals a day but you simply eat a little less. And we tell people that’s going to make you lose weight. The truth is it doesn’t. That’s the [purely 0:18:33.0] the what happened because we’ve all done it, and nobody loses weight. We look in society, and people try to lose weight by caloric restriction. It doesn’t work. And the question is why. The answer really is that your body, if it senses you’re only eating 1500 calories, it will quickly restrict you to 1500 calories of caloric expenditure. So now your body heat is lower, you feel cold, you feel tired, you feel hungry. So as you drop that caloric expenditure you don’t lose weight because now you’re eating 1500 and burning 1500, and you don’t lose weight. What happens during fasting is completely different because what you’re doing is you’re restricting time, not calories. So the signal, the hormonal signal you send to the body, which is by lowering insulin levels, particularly, is you signal to the body to start switching fuel sources. So now, for example, your body instead of burning food is burning fat, the fat that you have on your body because that’s all it is. That’s all stored food energy from previous meals that you will use when there’s nothing to eat.
If you’re always eating, like if you start eating a few snacks here and there throughout your fast all through the day, then your body’s like well I’m still getting food in. I’ll just burn that. It never switches fuel sources. So even if you eat 500 calories in that eating window, that four hours, or 800 calories, your body will actually make up those other 1200 calories from your body fat because it’s like whoa, during the time that you’re not eating it’s like well I have nothing to eat; let me switch over to this one. And it’s like okay, I have like tons of this body fat. I’ll just burn it, right? Whereas before if you kind of snacked throughout the day, just cut a few calories here and there, the fat stores are locked away. They’re not accessible to you. So then your body has to do reduce its expenditure. It’s kind of like if you have two fuel sources, like a hybrid car. You can do electric, or you can do gas. But if you lock away that gas component and only run electric, well, if the electricity goes down your car starts not moving, which is what happens to our body. As the food goes down, you go from 2000 calories to 1500, your body starts shutting down because you’ve locked away that gas. What we’re talking about with fasting is really trying to flip that hormonal switch to let you access that second fuel source, which is natural. It’s there in our body.
Fasting, Mental Clarity and Weight Loss
Which burns – ketones burn a lot cleaner, correct?
Yeah, the ketones is basically when your body doesn’t have glucose to burn, like food, then it will switch to burning fat. So most of the body can actually use that fat directly – so fats are triglycerides – but the brain can’t. So the brain, there’s a blood-brain barrier, so the triglycerides can’t actually get from the blood into the brain, and you actually have to produce these ketones from the fat which can get into it. So your brain actually still uses a little glucose, but up to 75% of your brain metabolism switches over to ketones, and this is one of the things we find during fasting is that people find that their mental clarity is much higher.
So it’s a very interesting thing, and people have noticed this kind of throughout history. There is some very interesting stories of Pythagoras, the very famous Greek mathematician. So in ancient Greece they used to fast, not because they were fat, not because they had type II diabetes, because they didn’t. It was to increase their mental capacity. So Pythagoras required his students to fast before they could come into his class –
Oh, is that right? That’s cool.
– which is amazing. And all of these famous Greek philosophers, they did fasting to increase their mental clarity. And we still talk about the ancient Greek philosophers and how smart they are, Pythagoras, these ancient Greek mathematicians. It’s like hey, that’s amazing. And here is something that you can use as a hack. People talk about hacks, which is these simple things you can do to make your body function better. So there’s people, for example in Silicon Valley, who will fast, not because they need to lose weight, but because they realize that they can actually function at a much higher mental level than if they’re eating all the time. And guess what; that means you’re more competitive. It means dollars and cents. And hey, why not? It’s like the perfect hack. So there’s lots of different reasons to do it.
Welcome everybody else. This is a great discussion. A question I have – well first of all a comment about mental clarity. I almost don’t even want to eat. Seriously, I’ve got to like force myself to eat. And people find that funny. But you wake up burning fat, and then I do bulletproof coffee with MCT, but that doesn’t really affect me too much.
Yeah, it doesn’t stimulate insulin. So pure fats don’t. So that’s why.
But the clarity I have in the morning, I actually look forward to getting up like at 4:30 or 5:00, and I work on podcast stuff or whatever. I’m so clear. And then later in the afternoon maybe because of my age or whatever, I start getting a little tired at night, but that has made a big difference. And I interviewed Brian and Danny from The Ketogenic Athlete, and they said the same thing. And the question I have for you is we all feel that now our body needs less sleep. I swear I sleep less. Is that something you see?
I mean, I do think that people do that. Sleep definitely is affected. And some people – a lot of people actually complain because they’re used to sleeping eight hours, and all of a sudden they say I can’t fall asleep. And what happens during fasting is that your blood glucose drops, so your body produces something called counter-regulatory hormones. So these are hormones that run counter to insulin. So the insulin tends to lower your blood sugars. These tend to raise your blood sugars. So what happens of course is that as you’re not eating your body actually wants to start pulling glucose back out from its stores and filling it up. So there are several main ones. Cortisol is a big one. Noradrenaline is a big one. And growth hormone. These are all counter-regulatory hormones. So part of the hormonal change of fasting is that these all go up, and they actually activate your body. So they are general activators. And noradrenaline, for instance, is like adrenaline. It gives you energy. Growth hormone allows your body to rebuild when you start eating, which is amazing. There are so many different benefits to that sort of growth hormone. There’s theoretical benefits, for example, for osteopenia or osteoporosis. There’s theoretical benefits for Alzheimer’s disease, all kinds of things in terms of letting your body kind of regenerate and renew itself, which is fantastic. Your body starts to break down a few of the old proteins, and then the growth hormone allows it to rebuild so you’re actually almost getting a kind of antiaging.
But getting back to the sleep, because it activates your body you don’t need as much sleep. And some people they try and force themselves. They go to bed at 10:00 every night for the last 30 years. Now they start fasting, and they’re up until 1:00. And it’s like, and I always tell them this is a natural response to the fasting. So if it really bothers you then you may have to adjust things. But really, just that’s some free time for you. You can go do work. You can go enjoy yourself. You can watch movies. You can do anything that you normally like because now your body is actually powered up and ready to go. And this is the thing that is – yeah, that’s where it’s beneficial to have somebody who understands what fasting is because they can tell you this is exactly what you’re going through, and don’t worry about it.
The other thing that people always come back to us very surprised is that they always say when I started fasting I thought I would be always so hungry, but it’s actually the complete opposite.
They go I think my stomach shrank. I’m always like I don’t think your stomach physically shrank, but it feels like it. And everybody always comes back. And it’s because what’s happening of course is that you’re now opening up fuel stores from your body fat. So your body is telling you I don’t need to eat that much because I can access all this huge stores of fat to power my body. So people will be fasting, and they’ll say I’m only getting like 600 calories a day, and it’s like yeah, but the other 1200 is coming from your body fat. That’s perfect.
That’s awesome, yeah.
And now I say well think about it. If you’re trying to lose weight that’s exactly what you want because if your hunger goes down, now you’re working with your body to lose weight instead of the previous way, which is portion control, count your calories, where it’s been proven that hunger signaling goes way up. And even during short-term fasts what’s interesting if you measure ghrelin, which is the hunger hormone, as you go longer and longer through a fast hunger does not go up. So this is the secret to how people can do these 7-, 21-, 31-day fasts is because by day two ghrelin peaks and then goes down. So day two is the day that you say oh man I am never going to make it through. By day five you’re like I could go on forever because your body is simply eating body fat. So it’s actually very interesting, and this is the thing, that nobody, because nobody fasts anymore – it’s been really out of style for like 30 years – there’s been nobody around to tell you that hey, this is normal. This is what to expect. It’s okay. This is how to deal with it. And that’s what we’re trying to kind of educate people and let them know and hold their hand and tell them don’t worry. There are lots of problems like constipation, headaches and stuff, but you can deal with them.
To confirm what you were saying about day two, I mean I think going into a five – I did a five-day water fast, and going into it I was low-carb anyway, so I think that makes it a little bit easier.
But day one and day two – I fast a lot anyway – wasn’t too bad. But by day three, four, five, absolutely no hunger to the point of even surprised me because I’m like I don’t even – I wouldn’t even want to eat right now. And then on day five I started, I thought you know, just I think you have to listen to your body. And after day five I’m like I think it’s been long enough. But I felt good. I mean I felt really good, and I think people should try it. I think people get so scared that I’m going to drop dead if I don’t eat every three hours, but it’s really good for your body. Question about – I’ve heard it pronounced two ways, autophagia or autophagy. How do you pronounce it?
I say autophagy.
I’ve heard it both ways.
When do you think that kick– well actually if you could explain that, and then when do you think that kicks in?
So autophagy is this process which is the breaking down of your own body’s kind of old proteins or slightly damaged proteins, and it probably starts somewhere between 18 hours, 24 hours, 36 hours. That’s probably the maximal time. So what happens is that if you look at the body during fasting, your body stores food energy as glycogen in the liver and body fat. Your glycogen will last you 24 hours, roughly. And then after that the fat oxidation really kicks in around 36 hours. So somewhere between 24, 36 hours there is this period where you actually do break down protein, and this is why some people have always said oh you’re going to eat all your protein. That’s not actually what happens because what your body is doing is selectively targeting those kind of damaged old proteins, and the other thing that people always forget is that growth hormone goes way up during a fasting period so that as you start to eat you are going to rebuild those proteins. Yes, there is breakdown. If you only look at the breakdown and don’t look at the kind of rebuilding you’re going to miss the entire beneficial process. So it’s like renovation. So you want to renovate your kitchen, or your bathroom or whatever. The first thing you’ve got to do is throw out that 1970-style lime green tub.
Which you found in your room.
That’s right. Our parents had like tons of this stuff. That’s hilarious. But the breakdown is just as important as the rebuilding. So if you look at, say, bone, because this may play a role in osteoporosis, for example, is that when you renew your bone the first thing you do is take a little chunk out of the bone and break it down. So the osteoclasts, they actually break down bone. And then you rebuild it. That’s how you get it. It’s a renewal process. So the autophagy has gained a lot of attention because the 2016 Nobel Prize for medicine was awarded to one of the researchers, one of the original researchers in it. But this is a way that the body can actually renew a lot of its old protein. So if you can do that, that almost reverses the aging process, and it’s like wow, that is amazing considering that benefit is available to everybody for free. It’s like that is like tremendous. So this is – a lot of new research is going into it. So you can’t say that there is a lot of proven benefits, but the theoretical benefits would be, say, for osteoporosis, for Alzheimer’s disease prevention and for cancer because a lot of these cancers, remember, are damaged cells. So if you look at the work of say some of the researchers like Dr. Thomas Seyfried in Boston, he says that everybody should do like a seven-day fast once a year because you want to get rid of all that old junk, including all those cancerous cells, and do this on a routine basis throughout like not like when you have cancer, but from the time that you’re an adult, do it once in a while to get rid of those old cancerous cells. Your body will break it down and rebuild proper cells. It’s like wow, that is fantastic.