New book from NYT bestselling author Lewis Howes is now available!

New book from NYT bestselling author Lewis Howes is now available!


Jason Fung

The Science of Intermittent Fasting (Foods To Live Longer & Reverse Type 2 Diabetes)

Live life longer, healthier, and to the fullest.

American-Indian author Deepak Chopra said, “If we are creating ourselves all the time, then it is never too late to begin creating the bodies we want instead of the ones we mistakenly assume we are stuck with.” And author Brian Wansink said, “The best diet is the one you don’t know you’re on.”

It’s no secret — the foods we consume on a daily basis drastically affect our physical, mental, and emotional health. Not only that, but the amount of time we spend eating them affects our health as well!

If we can get clear on what foods we should eat and when, then we are one step closer to leveling up our health. Healthy eating and intermittent fasting have amazing results — they’ve been known to reverse Type 2 diabetes, improve mental health, facilitate weight loss, and even help prevent cancer!

This Monday, I had the pleasure of interviewing Dr. Jason Fung — a leading expert on intermittent fasting and low-carb diets. We had such an incredible conversation that I had to split this interview into two parts! Definitely check out Episode 1,030 to get the scoop on intermittent fasting, cancer prevention, and whether we should take vitamins and supplements.

Today, I’m sharing Part 2 of our conversation with you! It’s full of amazing information that’s sure to level up your health and improve your life!

Who Is Dr. Jason Fung?

Dr. Jason Fung, MD, is a Toronto-based nephrologist and a world-leading expert in intermittent fasting and low-carb diets. He is also the bestselling author of The Diabetes Code, The Obesity Code, and The Complete Guide to Fasting, and the creator of the Intensive Dietary Management program as well as co-founder of The Fasting Method.

After graduating from the University of Toronto and completing his residency at the University of California, Los Angeles, Dr. Jason returned to Toronto to work as a kidney specialist. He began to work with patients to prevent and treat Type 2 diabetes and obesity — both precursors to kidney disease.

He started by prescribing more conventional solutions — low-fat, low-calorie diet, and exercise — but he found that such conventional treatment plans weren’t truly helping his patients lose weight and get healthier. That’s when he decided to think a little outside the box.

Dr. Jason, along with his friend and professional partner, Megan Ramos, co-founded the Intensive Dietary Management program and The Fasting Method to help their patients truly lose weight, prevent obesity and Type 2 diabetes, and completely avoid kidney disease. They started seeing real results in their patients, and now, they’re beginning to see that fasting can also lower our chances of getting cancer.

Dr. Jason fundamentally believes in the power of intermittent fasting to help people lose weight, lower their blood glucose levels, reduce their medication dependency, and improve their overall health. His work is positively impacting thousands of people around the world, and today, he’s sharing his wisdom and knowledge right here on The School of Greatness on Part 2 of the episode!

In this interview, Dr. Jason Fung shares how to use intermittent fasting if you’re an athlete, how mental health affects our physical health, and his three most important lessons for living a healthy life. Trust me — you’re not gonna want to miss this one.

How to Reverse Type 2 Diabetes via Fasting 

In our interview, Dr. Jason gave a shocking statistic — almost 50% of the American population suffers from prediabetes or Type 2 diabetes: 

“About 10% – 15% is Type 2 diabetes. About 30 – 35% is prediabetes. So the point is that if you put all that sugar into your body, what happens is that you can cram it in, but then all that sugar sort of goes all over the body. And every single organ just starts to rot away.” – Dr. Jason Fung 

Prediabetes eventually leads to Type 2 diabetes, which is extremely harmful to the body and, in some cases, even life-threatening. How do people develop Type 2 diabetes? The answer is simple: an overabundance of sugar.

“Imagine your body is a sugar bowl. And over the years, you’re sort of eating a lot more and not using it up. So the sugar builds up, builds up, builds up. Eventually, it gets to the point where it starts to overflow. And that’s basically what Type 2 diabetes is. You’ve stored up so much sugar in your body that it overflows into the blood.” – Dr. Jason Fung

People suffering from Type 2 diabetes often take insulin shots, but Dr. Jason says that this treatment is actually counterproductive in the long run. Instead of getting rid of the sugar that has overflowed into the body, insulin merely “crams” it back into that initial sugar bowl — which will eventually overflow again. The solution to curing Type 2 diabetes isn’t insulin — according to Dr. Jason, it’s getting rid of most sugar and giving your body time to burn it off:

“The solution is not to put more and more [insulin] to push it in. The solution is to get rid of all that stuff. … The solution is to get rid of all that sugar. So how do you do that? There [are] only two things you need to know: Don’t put it in and let your body burn it off.” – Dr. Jason Fung

There are tons of ways you can do this — going on diets, taking supplements, etc. — but the method with the most results is intermittent fasting combined with a low carbohydrate diet. Dr. Jason used the analogy of going to the gas station to fill up your car — you don’t go to the gas station three times a day to fill up the tank, do you? If you did, the gas would overflow (and it’d be a waste of money, right?). 

“[It’s the] same as the body. Every time, you’re just putting more sugar and putting more sugar. … [Instead,] run that body without sugar for a while. And that’s what intermittent fasting does. And that’s why we were able to reverse [Type 2 diabetes]. We wrote a case series about three patients who we did this for. We just reversed the diabetes — like, they had 20 years of diabetes, and we reversed it in them.” – Dr. Jason Fung

Do you suffer from Type 2 diabetes or prediabetes? Do you know someone else who suffers from it? It’s sadly becoming more and more prevalent, but thankfully, there is a way to reverse it. Type 2 diabetes can completely wreck your internal organs, give you kidney disease, increase your risk of heart attack, and shorten your lifespan, but you don’t have to let it. I’d encourage you to talk to your doctor about intermittent fasting and whether or not it’s right for you. And if you want to learn the specifics about intermittent fasting, I encourage you to check out Part One with Dr. Jason Fung where he explains the different methods!

“It’s 100% possible to reverse Type 2 Diabetes by practicing fasting and getting rid of sugar.” @drjasonfung  

Can Athletes Use Intermittent Fasting? 

Even if you don’t suffer from prediabetes or Type 2 diabetes, intermittent fasting has so many benefits to your overall health. In Dr. Jason’s new book, The Cancer Code, he explains how intermittent fasting can reduce your risk of cancer and other diseases! 

But what if you’re an athlete, and you need a high-calorie diet to supplement all the exercise you’re doing? Can you still use intermittent fasting to upgrade your wellness? I asked Dr. Jason for his thoughts:

“You have to differentiate between the weekend athlete, the one who really isn’t at that super high level of competition, [and the professional athlete]. … So if you’re one of these guys who works out two or three times a week … [fasting] is perfectly acceptable because if you don’t eat, your body will simply take those calories that it needs from your body fat.” – Dr. Jason Fung

If you work out on a moderate level, intermittent fasting is not off limits! In fact, it will help you burn off fat at a more efficient level and make room to build muscle. However, if you’re an elite athlete, chances are that you need those calories. 

“Most [elite athletes] don’t have enough body fat to sustain [that sort of fasting], right? … So what we do there, and we’ve worked with a number of elite athletes, is that you have to separate what you’re trying to do. So in the ‘on-season,’ you can’t really fast. It’s hard to do. You need too much energy.” – Dr. Jason Fung

Here’s the bottom line for athletes: It depends on your body type, your sport, and other health factors. As always, it’s important to talk to your doctor before trying intermittent fasting, especially if you’re a high-performance athlete!

Dr. Jason Fung’s Top Five Foods to Eat for a Healthier Life 

Of course, intermittent fasting is not as powerful if you don’t eat the right foods in the first place! If your diet is composed solely of carbs and sugars, then the odds are intermittent fasting won’t give you the results you’re looking for. What you eat directly affects your mental, emotional, and physical health, so it’s important to get clear on what foods you should eat and what foods you should avoid. 

Whenever I have health experts come on The School of Greatness, I love to ask them about their favorite foods for a healthy lifestyle and why they love them. I asked Dr. Jason this same question: “If you could only eat five foods, what would those be, based on your scientific research/benefits they have for the body?” Here are his answers: 

#1. Meat 

There’s a lot of debate on meat — both ethical and environmental — but from a nutritional point of view, Dr. Jason says that meat is one of the most nutritious foods out there. 

“Fish and chicken for sure would be up there. And, you know, scientifically, of course, [meats are] much more complete sources of protein for us because we’re animals. So, therefore, we use animal proteins much better than we can use plant proteins.” – Dr. Jason Fung 

If you’re not a meat-eater, don’t worry — there are many other foods that have nutritional benefits and proteins as well!

#2. Beans 

If you’re a vegetarian, beans are a great source of protein to supplement your diet! 

“People have eaten beans for … millennia — like [they’ve] subsisted on beans and so on. So that’d be a … vegetarian source of very good protein and can actually be quite delicious!” – Dr. Jason Fung 

#3. Avocado 

One of Dr. Jason’s favorite fruits is avocado! 

“I think everybody loves avocado, and there are so many vitamins in there and so on.” – Dr. Jason Fung

In addition to having lots of vitamins, avocados also contain amino acids and help decrease the risk of diabetes, heart disease, and other health concerns.

#4. Cauliflower and Broccoli

If you’re looking to replace a carbohydrate side dish, look no further than cauliflower and broccoli! These two vegetables are rich in nutrients and are much better for your body than mashed potatoes or even rice!

#5. Tofu

Lastly, Dr. Jason said he loved tofu, and it’s a great vegetarian protein option as well! Tofu also contains a lot of amino acids and nutrients, such as potassium, iron, and manganese. 

Remember: If you don’t supplement intermittent fasting with a healthy spread of foods, such as the ones above, it won’t have its full effect. To level up your health, it’s essential to look at it from a holistic standpoint so that you have everything working for you instead of against you!

How to Live Longer and Fuller: Go into Maintenance Mode

By eating healthy and not too often throughout the day, we increase our odds for a long, full life! Dr. Jason broke down the science for us in a way that everybody can understand: 

“Our body has sort of two ways that it can go. You can either go into sort of growth mode or [you] can go into cell repair and maintenance mode. And the way you do that, of course, is by eating less, and fasting plays a big role in that. Because again, if you eat, then you’re going to activate the nutrient sensors. … If you’re young [or a kid], that’s fine. But think of it like a race car, right? You rev that engine, you’re going to go really fast, but you keep revving the engine, [and] it’s not going to last for very long, right? So you need to put that engine into sort of storage for a little while if you want to maximize the length of it.” – Dr. Jason Fung

I love the metaphors Dr. Jason uses. It makes total sense, right? Life isn’t a sprint — it’s a marathon, and to run it, we need endurance. Intermittent fasting helps us tap into that longevity. As Dr. Jason says, “We’re designed to eat until we’re full and then stop.” In our society today, it’s so easy to just keep eating and keep eating — just because the food is so readily available to us. But if we break up our meals with periods of fasting, we take our bodies back to that maintenance state. 

“As you get older, you want to push yourself into that longevity stage, which means eating less, which means doing more fasting.” – Dr. Jason Fung 

Another thing that helps us live longer is our mindset:

“So when people talk about positive attitudes and gratitude and community and staying connected and all that sort of stuff, it sounds hokey, but it actually has a huge impact on life and quality of life and even longevity.” – Dr. Jason Fung 

It can be difficult to study the effects of mindset on health, but more and more people are noticing that those with healthier mindsets have healthier bodies. Dr. Jason explained that there are hormones released when you’re happy, and your immune system improves when you’re in a good mood!

“The immune system, which under chronic stress winds up getting degraded, right? … If you’re under too much stress, your immune system really doesn’t work as well. And the immune system plays a key role in fighting cancer.” – Dr. Jason Fung

If you can take care of your body, while also taking care of your mental and emotional state, you are much more likely to live a longer, fuller life!

Why You Should Listen to This Dr. Jason Fung Podcast Episode Right Now…

This interview was extremely eye-opening for me — it’s full of so many great tools and valuable information that you can use to level-up your health and live a longer life! 

I want to acknowledge Dr. Jason Fung for his amazing analogies — he turns the complex into something that is understandable and easy to break down. Cancer, obesity, and diabetes can be very hard to understand when you’re dealing with the sickness itself, but the fact that he is able to communicate effectively and simply is so powerful for the rest of us. 

I also love Dr. Jason’s definition of greatness:

“I think, you know, that greatness is really about being able to impact people in a positive way. … to be able to impact somebody so that … they’ll be able to lose weight or they’ll be able to reverse their diabetes or understand cancer better as a disease. [Helping people] is a humongous privilege.” – Dr. Jason Fung

Dr. Jason lives by that definition, and he’s impacted so many people in such a healthy, positive way! I was honored to have him on the podcast for a two-part interview, and I know that I personally learned so much. Definitely check out Part One if you haven’t already! 

If this interview impacted you, we would love to hear about it! Tag Dr. Jason, @drjasonfung, and me, @lewishowes, on Instagram with a screenshot of the episode and your greatest takeaways! 

Remember: Your health isn’t out of your control. There are so many different things you can do to give yourself the upper advantage!

To Greatness,

Lewis Howes - Signature

Some Questions I Ask:

  • What causes Type 2 Diabetes?
  • Can you fast if you are an athlete?
  • Is fruit good or bad for us?
  • What are Dr. Jason Fung’s top five foods?
  • Can fasting help us live longer?
  • Is it okay to eat junk food if we are on intermittent fasting?

In this episode, you will learn:

  • The importance of intermittent fasting.
  • The biggest myth about the Ketogenic Diet.
  • How our mental health affects our physical health.
  • Dr. Jason Fung’s three most important lessons for living a healthy life.
  • What he believes older religions got right about diet and lifestyle and how we can learn from them.
  • Plus much more…

Show Notes:

Connect with
Jason Fung

Transcript of this Episode

Music Credits:

Music Credit:

Kaibu by Killercats

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