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Transcript of the No-Bullshit Vegan podcast, episode 78

Robby Barbaro on mastering diabetes and insulin resistance with a plant-based diet

Karina Inkster: You're listening to the No Bullshit Vegan Podcast, episode 78. Robby Barbaro, co-founder of Mastering Diabetes, is here to discuss reversing and managing diabetes with a plant based diet.

I'm Karina, your go-to, no-bullshit vegan fitness and nutrition coach. Thank you so much for tuning in today. We are going to discuss all things diabetes, but also the concept of insulin resistance and how it might affect you, even if you don't have diabetes. There’s going to be something for everyone in this episode.

First, if you haven't yet checked out my ebook Sprouted Gains, just FYI, it's currently on sale at It is a full-length book that shows you how to enjoy delicious plant based foods, while making sure you nail your fitness and physique goals. The best part is: you don't have to cut carbs. You don't have to chug three or five protein shakes a day. You don't have to forego your favourite foods, or spend five hours meal prepping every Sunday. So that's all great news for you. This comes with a bonus companion guide, which includes sample food logs and interviews with vegan experts. Right now this whole package is on sale for $19, instead of the usual price of $39. Head to to get your hands on your copy!

Now allow me to introduce my awesome guest for today, Robby Barbaro. Robby graduated from the University of Florida and is the cofounder of Mastering Diabetes and Amla Green. He helped to build the revolutionary brand Forks Over Knives for six years, before turning his attention in 2016 to mastering diabetes full time. Robby was diagnosed with Type 1 diabetes at the age of 12, and has been following the Mastering Diabetes method since 2006. His current A1C is 5.3%, while maintaining a Time-In-Range of 92%, which is very impressive. By the way, Robby says his favorite vegan food is mangos, mangos and more mangos. Hey Robby, thanks so much for joining me.

Robby Barbaro: I am really excited to be here today. Can't wait to talk about some interesting topics.

Karina Inkster: This is going to be interesting, indeed. We actually have not covered diabetes before on this show, in any sort of detail. This is going to be awesome. Let me start with some basics here. Can you tell our listeners and me a little bit about what you do with Cyrus and your book, Mastering Diabetes?

Robby Barbaro: Absolutely. Cyrus and I are both living with Type 1 diabetes, which of all the people living with diabetes, that's about 5%. It's actually a smaller group. Type 1 is where your pancreas has been damaged, and it's not producing sufficient quantity of insulin. We need to inject insulin in order to eat food and stay alive. Now, the majority of people are living with Type 2 diabetes, and that's initially characterized by an excess production of insulin. It's just that their body is not using it efficiently. That is insulin resistance, which we'll get into today in detail. It’s the same thing with prediabetes; prediabetes is caused by insulin resistance. Then there's Type 1.5 diabetes, which is a slow, onset version of Type 1 diabetes. Again; that's an autoimmune condition where you end up taking insulin because it’s required. And then there is gestational diabetes, which is a type of diabetes that occurs during pregnancy. Again, the primary cause is insulin resistance. 

So the cause of pre-diabetes, the cause of Type 2 diabetes, the primary cause of gestational diabetes, is insulin resistance; insulin resistance can be present in those living with Type 1 and Type 1.5. So we wrote a book and the title is Mastering Diabetes: The Revolutionary Method to Reverse Insulin Resistance Permanently in Type 1, in Type 1.5, Type 2, Prediabetes and Gestational Diabetes. That subtitle is super important and super clear: our entire message, everything Cyrus and I do, what our company does at Mastering Diabetes, is a platform to teach people how to reverse insulin resistance. We teach about what it is, what causes it, and how you can turn it around. What's important for people to know is that insulin resistance is at the center of a laundry list of chronic conditions, such as heart disease, fatty liver disease, cancer, chronic kidney disease, high blood pressure, high cholesterol, PCOS, erectile dysfunction, Alzheimer’s disease, and the list goes on and on and on.

In addition to those chronic diseases, there are common ailments such as headaches, bloating, low energy, inability to lose weight, brain fog; which are also caused by insulin resistance. There really is a universal application here, and a reason for people to really understand what's going on here about insulin resistance and how to reverse it. It just happens to be that as people living with Type 1 diabetes, we are the ultimate test subjects, for this entire concept of insulin resistance on a day-by-day basis, because we know exactly how much insulin we inject. We count our carbohydrates, and we monitor our blood glucose levels on a daily basis. Those three data points give us an incredible insight into insulin sensitivity. That's what led Cyrus and I to be very interested in this topic and study. Now here we are at Mastering Diabetes, sharing this information with people. We’ve had thousands upon thousands of people run through our coaching program, people listen to our podcast and our social media, we do lots of webinars, and we do an online summit and in-person retreats. We have a lot going on, but again, all focused on one thing: teaching people how to reverse insulin resistance.

Karina Inkster: Amazing. Thank you for that. We are going to talk about insulin resistance. Of course, I'm sure our listeners right now are like, "Holy crap. I need to learn more about this!” First, why don't we just take a quick detour here, and do a little bit of background on the conventional approach to diabetes. Then we're going to spend the rest of the time on your approach to diabetes, which is more effective, more evidence-based. What is the deal with the conventional approach to diabetes? It's very carb-centric. Can you summarize this for our listeners?

Robby Barbaro: That's exactly right. The conventional approach to diabetes is that the condition is characterized by high blood glucose levels. In order to have prediabetes, and develop Type 2 diabetes, you must have elevated blood glucose levels, meaning there's too much “sugar" in your blood. People think, "okay, then I guess I should just not eat things that contain glucose or you know, things that convert to glucose efficiently. I shouldn't eat fruit. I shouldn't eat potatoes. I shouldn't eat rice. I shouldn't eat beans. I shouldn't eat butternut squash.” 

That belief gets supported when people test their blood glucose levels. There are many people living with Type 2 diabetes, Type 1 diabetes, any form of diabetes. They'll be like, "okay, you know what? I'll listen to these Mastering Diabetes guys. I will try and eat some fruit. I'll have two bananas.” Then they test their blood glucose, and boom: they're high. You're supposed to be somewhere between 80 and 130. Then they eat a meal an hour later, two hours later, they test their blood and they're 200, 250, 300. They say, "what are you guys talking about? This? You guys are a bunch of jokers. I have the evidence right in front of me”. The diabetes community will literally say this: I eat by my meter. When the meter says that those foods will make me go high, I'm not going to eat them. But, if I had some bacon, or I had some cheese, or some very, very low carb food, then I don't see my blood glucose go up. It actually stays steady. It stays flat. No problem. I understand where the confusion is coming from in peoples' personal experience. What they don't understand what's missing is the cause of that elevated blood glucose level. That is the dietary and lifestyle habits, which preceded the experience of trying to eat two bananas. That's where the confusion comes in.

Karina Inkster: Makes total sense. Now, I'm sure our listeners are wondering what the hell is insulin resistance in the first place? This is the focus of your approach. It's not a band-aid solution, which the conventional approach kind of sounds like. “ You have this symptom, let's fix the symptom, but we're not addressing the cause.” (That’s my understanding of it).

Robby Barbaro: That's exactly right. That’s what is happening.

Karina Inkster: You’re focusing on insulin resistance as one of, if not the main cause. Why don't we define it first? What is insulin resistance, first of all?

Robby Barbaro: Insulin resistance is the diminished ability of cells to respond to the action of insulin, in transporting glucose from the bloodstream into muscle and other tissues. What that means is when you're living with insulin resistance; your body is struggling to take glucose out of your bloodstream, and into your cells. It's insulin's job to open the door and allow the glucose to go out of your bloodstream, into your cells. When that process is inhibited, you then develop insulin resistance. 

There’s a distinction here between physiological insulin resistance and pathological resistance. The typical Type 2 diabetes diagnosis (we're talking about over 26 million people in the US alone living with Type 2 diabetes, over 110 million living with either prediabetes or Type 2, because there's 84 million living with prediabetes that don't even know.) I'm talking about a large number of people here, who are struggling with this. It’s their body developing pathological resistance, where not only do they have high blood glucose levels, but they also have high insulin levels in their blood stream, because their body is trying to compensate for this air, for this dysfunction of not being able to open the door.

The pancreas just says, you know, I'll just keep producing more and more and more insulin, trying to shove that glucose into your cells. Eventually, it just gets to the point where it can't keep up anymore. That's when you'd start developing prediabetes, and it gets worse, then you develop type two diabetes.

Karina Inkster: Gotcha. You mentioned in the intro, a lot of these different types of symptoms, like headaches and brain fog and you know, energy issues and things. How would someone know that they're insulin resistant?

Robby Barbaro; Again, it's very easy if you are living with Type 1 diabetes, because you know exactly how much insulin you're injecting, and you know exactly what your blood glucose levels are. You can have that relationship: “okay, wait a minute. Every time I eat food, I need to inject a lot of insulin. Therefore, I can see the insulin resistance”. For people like you, and the majority of people listening to this show, you don't know how much insulin your pancreas is secreting at any point through the day. You don't know if it's more, or less, you just have no idea. The easiest way to objectively understand would be to get an A1C test. An A1C test is an average blood glucose reading over the course of three months. It's an indicator of your average blood glucose levels, over the course of three months.

Once you hit 5.7%, you're in the prediabetes range; 5.6% and below is non-diabetic. Once you hit 6.5% or higher, then you are living in the Type 2 diabetes range. An A1C is a good way to go for an objective answer. I can tell you right now with, with high confidence, anybody listening to this show who is struggling to get to their ideal body weight, who has low energy in the afternoon, experiences that brain fog, experiences headaches: if they started to apply the Mastering Diabetes method, the principles that we teach (which are all about habits that improve insulin sensitivity), those symptoms will likely begin to disappear and improve. As you adopt the lifestyle, as you make the changes and you see the improvements, you can then infer that you were probably having some insulin resistance going on, even though the A1C was okay. You’re still on that edge. Things are a little off here. Once you optimize it, you start to feel better and that's really all that matters.

Karina Inkster: That makes sense. We've got a good understanding of what insulin resistance is in the first place, how you might be able to tell that you're insulin resistant, and how you (for sure) can tell from testing where you're at with blood glucose levels. What can our listeners do, along the lines of what you teach people you work with, to fix this problem?

Robby Barbaro: I'm going to tell you how to fix it. I'm going tell you what causes it, but I should also add one thing that people could do. If you wanted to see if you're insulin resistant, if your body is struggling to metabolize glucose, you could just do a simple finger prick. If you test your fasting blood glucose, and your fasting blood glucose is in the 140’s, if it’s above 100, we have a problem (140’s, 160’s, 180s, 200: we have a huge problem.) Or, you could test your blood glucose two hours after you finish a meal. If that's elevated above 140, then you're likely living with insulin resistance. This is a simple test that you can get. You can buy a blood glucose meter at any pharmacy. They're quite inexpensive and all of them are fairly accurate these days. That's another way to test it. 

Back to your question: we have to understand what causes insulin resistance. What prevents insulin from working efficiently, opening that door, and letting blood glucose in, in a graceful, smooth manner like your body is designed to do? We know, through a hundred years of evidence-based research, that excess dietary fat stored in muscle and liver cells is the cause of insulin resistance. I know a lot of people listening to that might be say, "wait a minute, wait a minute. I've been learning about the keto stuff. I read about the keto stuff." There's all these people who are eating nothing but fat. They are just going hardcore on the fat, and they're losing weight. Their A1C is dropping. They're getting off diabetes medications. Their blood glucose is flat. (They would say) how can you tell me that insulin resistance is caused by consuming excess dietary fat? Here's where the confusion sets in.

In order to say that you have reversed insulin resistance, or you've reversed Type 2 diabetes or prediabetes, you must be able to metabolize glucose. You must be able to process glucose. What's happening in the ketogenic world, in the low carbohydrate world, is that they're simply removing high carbohydrate foods. 

Imagine you're a bad driver. You get in car accidents all the time. You get speeding tickets all the time. You're just a flat out bad driver. If we take away your license and you don't drive anymore, then you don't get any more speeding tickets, and you don't get in any more accidents, but we didn't solve the problem. We didn't teach you how to become a better driver. In the low carbohydrate world, what's actually happening (unfortunately) is they're making the condition worse by removing carbohydrates. When you go back and you try and eat a little bit of carbohydrate rich food: just a pint of blueberries, a banana, a cup of quinoa, a half a potato: they see their blood glucose skyrocket. They become more insulin resistant, and that's what's happening. 

Like I said, this research goes all the way back to the 1920’s. Insulin was first discovered in 1921. It was first used in a human in 1922. Research as early as 1926 showed that as patients increase their carbohydrate intake from fruit and potatoes and bread, they became more insulin sensitive. This research continued into the 1930s, and researchers concluded studies. In a study concluded in 1935, Dr. Rabinovitch says: "carbohydrates increase, whereas fats decrease, the sensitivity of an individual (animal and man) to insulin." This is in 1935. They're doing all kinds of elegant experiments in humans. They did experiments in humans who actually weren't living with diabetes, but had a healthy level of insulin being produced and said, "okay, wait a minute. How efficiently does it work, as we change the amount of dietary fat in the patient's diet?”

This is published in a British medical journal, in 1934. Researchers concluded: "it is evident that on a high fat diet, insulin takes longer to act, and it acts more slowly on the blood sugar when the subject is given a high fat diet.” It just goes back a long, long ways. I don’t want to go through the whole research here, the whole history; we talk about it or book. We have a video on our YouTube channel. We have 18 studies that I went through, explaining how glucose tolerance improves as you increase your carbohydrates content. The bottom line is: when excess fat is stored in muscle liver cells, your body is using its brilliant wisdom to prevent more energy from coming in. This is your body's defense mechanism saying "I have so much fat inside my cells. I have so much energy in here; I don't want any more glucose. I am going to make it very difficult for the door to get open, and to have that glucose come into my body.” That’s the mechanism, in a very simple way, being explained. Obviously, it’s a heck of a lot more complex. There's a lot of biochemistry involved, and a lot of nuances, but it's an energy protection mechanism. Your body says, “ I have too much. I don't want more." That's what happens.

Karina Inkster: Interesting. Why the heck, if there's all this research, are we still using the conventional approach (a very carb centric one)? Why is that approach still being used?

Robby Barbaro: It's mind boggling to me, it truly, truly is. Here's one of the most interesting parts about it. So much of the passion and the inspiration for what we do here come from our personal experience. Cyrus and I both had an incredible turnaround in our own insulin sensitivity, when we started following this totally unconventional approach of eating tons and tons of fruits and vegetables, and just seeing the exact opposite happen of what we expected. What's interesting is that all it takes is somebody willing to try it, just give it a shot. In a matter of days, people will see a difference, especially if they're using diabetes medications, but even just energy wise, mood wise; the change is dramatic when you really implement the Master Diabetes method. I will be honest. Our method is very, very particular and it's very, very, clean (might be the best word). It’s very, very whole foods focused.

We kind of take the plant based diet to a little bit of a next level. I mean, I spent six years building the Forks Over Knives brand, and had a lot of fun there, and know a lot about the nuances of a general plant based diet. Ours is a turbocharged version, to maximize insulin sensitivity and get really, really rapid results. I think a lot of the confusion comes from the fact that (again, like I said earlier) with diabetes, it's this ability to self monitor, and be able to see what happens when you sort of test on yourself, that gets people confused. There are very few conditions where you can actually see the disease getting worse or better objectively, on a meal-by-meal basis, all by yourself. You can self-monitor. If you have heart disease, if you have kidney disease, you don't know. Did things get better or worse based on that one meal? You're not sure. You don't have any data. The fact that people with diabetes can eat foods, then test their blood glucose, and then see the number being high: if you don't have the knowledge of why that happened, you're think "I'm not going to eat those carbohydrates foods anymore. They just made my blood glucose high”.

It’s partly that. Also, I think part of the issue is people don't fully understand. The solution here: it’s a low fat, plant-based whole food diet, particularly low fat, because we have to get rid of this excess dietary fat and muscle liver cells. What we're talking about here is a very specific protocol, which is designed to address people who have glucose metabolism issues. They have high blood glucose levels. We have to do that by making sure the diet is low in fat. Most people don't know how to execute that. They think they're executing it, but they're not, because high fat foods are so calorically dense that a small amount goes a long way.

This confusion about what is a truly low fat diet has unfortunately seeped into the peer-reviewed literature. You can go look at some of the top, top journals. We're talking The Lancet, British Medical Journal, Nature, you name it: high quality journals that have published papers, comparing a low fat diet to a low carbohydrate diet, and concluding that the low carbohydrate diet performed better. The problem is, they didn't actually study a low fat diet. What's happening with the research is, they'll study a diet with 26% of calories from fat, 30% of calories from fat, 35% of calories from fat, not with whole foods like what we're calling for here, and they call that a low fat diet. 

This mistake is made repeatedly, but we go through the research in our book, on our website, and in our presentations. We demonstrate what happens when you feed humans a whole food, plant based-focused diet, where the maximum percent of calories come from fat is 15%. What happens when you do that is you see an extraordinary turnaround and improvement in insulin sensitivity, across the board. In 1979, James W. Anderson reversed Type 2 diabetes in 50% of his patients in just 18 weeks. In 1955, Dr. Inder Singh published a study in The Lancet. He reversed Type 2 diabetes in 80% of his subjects. It was 18 weeks for Singh’s study. I can go on and on and on. Literally, there is no study that I have found, to the contrary: when people eat a whole food, low fat diet (15% maximum calories from fat), the results are consistent across the board. These are improved insulin sensitivity, weight loss, getting off diabetes medications, feeling better, and just getting back to a normal, healthy life.

Karina Inkster: Interesting. This 15%, which is truly low fat (I mean, that’s very little fat) that is specifically for people who are prediabetic, or people who have diabetes. You’re not saying this is a one-size-fits-all approach to anyone who wants to be healthy, right?

Robby Barbaro: It could work that way, but in general, yes: it is absolutely, specifically designed for people who have a chronic disease and they're trying to get out of that. When you have a problem and you're trying to reverse it, it's much different than somebody who's young, who may not have any health problems yet, and they're trying to make sure they don't get any health problems. There's this element of metabolic flexibility that people talk about. There's just a lot more options. When you're trying to get out of a chronic disease, we highly suggest that people stick with this approach.

Karina Inkster: A couple of more questions around the fat, then. If people are signing on for this approach, if they want to reverse diabetes, do you recommend tracking food, in MyFitnessPal (or something like that), so that they know that they're staying below this 15%?

Robby Barbaro: That's a great question. I love that question. I'm all about the nuances. I love the details. That's how we started a coaching practice. If you're living with insulin dependent diabetes, and you are injecting fast-acting insulin at each meal to compensate for a pancreas that's not producing enough insulin, then using nutrition-logging software, and being aware of how many grams of carbohydrates you're consuming is critical. That's how you figure out how much insulin to dose. I personally use an app called Cronometer, which is just like MyFitnessPal. That's the one that we choose that we recommend, but MyFitnessPal is great (they’re all great)! It's a matter of using it. Whichever one you're willing to use, that's the best one. In that case, yes. We do advocate that people take the time to use nutrition-logging software as an educational tool, just to become aware of how many carbohydrates are in a certain food, how much fat is in certain food, and a lot of people are just blown away. Their mind is opened when they actually see the objective data, and say "wow, I had no idea there were so many calories and so much fat in that handful of nuts. I had no idea there was so much fat in that tablespoon of olive oil that I've been using. I had no idea that tofu, tempeh, and edamame were high fat foods. I didn't think that half an avocado would put me over my fat limit so quickly.”

The other thing that people learn, which I think is a very important point here, is that when you eat enough calories from whole plant foods, you automatically get a significant amount of fat, just from whole plant foods. There are essential fatty acids in every plant food that you eat. That includes lettuce, bananas, apples, quinoa, potatoes, and oats: all whole foods have essential fatty acids. When you eat a significant amount it actually adds up, and you can simply meet your requirements through whole foods. We also encourage an "insurance policy", which is a tablespoon of ground chia seeds or ground flaxseeds each day. You have that at breakfast, and right then and there, you have automatically met your need for essential fatty acids. In addition to that, our program (the dietary protocol we're talking about here) has a healthy Omega 6 to Omega 3 ratio. You want that ratio to be about 4:1, or 1:1, somewhere between there. For every Omega, every 6 fat that you have (every gram), you could have upwards of 4:1. The point is most people consume too many Omega 6 fats, through processed oils, and processed food in general. 

The reason that's a problem is because the same enzyme that does the conversion process for your central fatty acids works on both sides. When you eat too many of the Omega 6 fats, that is the preferred pathway for that enzyme. That enzyme has to go and handle all the excess fat on the Omega 6 side. There's not enough left on the Omega 3 side to do the all-important conversion of taking ALA, and converting it to EPA and DHA. This concern around " if I'm going to follow a low fat diet, I might not get my essential fatty acid requirements met. I might have hormone issues.” This is not a concern when you don't consume too many Omega 6’s, which is rare. Most people are blatantly just consuming way too many. That's an important nuance, and I'm bringing it back to the software. The software can tell you that. When you take the time to enter your food, you will understand, what your Omega 6 to Omega 3 ratio is. When you observe that, you can start making changes.

In the long-term, we don't want people to have to enter food into nutrition-logging software all the time. We think that people should learn how to eat, and eating should not be difficult. It should be easy and graceful and enjoyable. All you have to do is just understand a few principles in order to make sure your fat is not getting too high. Those principles are just simply understanding which foods are high in fat. We have a green light list of foods, a yellow light list, and a red light list, to make it very easy. The yellow light list includes higher fat plant based foods. As long as you're aware of what those are, and you're cognizant that you should have one serving of those per day (not one of each or two more servings); if you just pick one serving of the high fat, yellow light foods, and then the rest comes from the green light category, you literally don't have to think about it. You don't need to enter anything into software to know that you didn't consume an excess amount of dietary fat, that you actually ended up in a 4:1 (or somewhere between 4:1 and 1:1) on your Omega 6 to Omega 3 ratio, just by eating the foods in the green light category and not too much in the yellow. It really is that simple.

Karina Inkster: You know, I like how you called the software an educational tool. That's exactly the term I use with my clients. It's not something I want people to do forever and ever, and ever. I think we're on the exact same page here for different reasons, of course. My clients are more strength trainees, and they're working on body composition, and things like that. It's the same kind of concept, where it can teach you some interesting habits. It can open your eyes to some really interesting data, but who wants to be attached to an app for the rest of their lives, tracking their food? It's not really a sane approach to nutrition.

Robby Barbaro: Totally. That's cool. I love that you do that.

Karina Inkster: I mean, it's useful, but again, it's not a long-term approach, I don't think.

Robby Barbaro: One thing I was going to say, I'll add one more thing on that because it's an important topic. For those living with insulin dependent diabetes, where you truly do need to figure out how many grams of carbohydrates you're having, you can get pretty good at the guess and check game. But another way to do it, something we wrote about in our book, is there are go-to meals. A go-to meal is something that you love, you enjoy, and you have the exact same thing repeatedly. If you have two medium sized apples, a banana, and a medium size pear, and you put some chia or ground flax seeds on top, a little bit of lettuce: that’s a meal that you could have repeatedly. That could be a nice breakfast meal. If it's the same amount of oatmeal, plus the cup of blueberries, whatever it is: you can establish go to meals that you know how to dose for. You just do it repeatedly.

Karina Inkster: That's a good point. A lot of us eat the exact same breakfast every day. For example, I do. It's been the same for, I don't know...17 years probably. Speaking of fruit: one thing that I wanted to ask before we transition into some more things around like low carb diets, and things that might apply to a greater population of our listeners, was around fruit. The conventional, so-called wisdom around fruit is that it's high in sugar. If you eat it, you're going to spike your blood sugar, and that's not good. So...don’t eat it. We know already from what you've said, that that's not the whole story. If you address the insulin resistance issue, the core issue, then that shouldn't be a problem. Is that true? Where does fruit sit in this whole way of eating?

Robby Barbaro: At Mastering Diabetes, we are very, very fruit forward. We love fruit. It really is a magical food on a lot of levels. It's just a powerhouse nutrition package. Number one: fruit is a very high water content food, and the most pure form of water that you can possibly consume is the water that comes in whole fruits and vegetables. Nature has filtered it, and that is the best place to get water. In addition, fruit is loaded with fiber, which is important for not just your overall health, but your micro biome, which we're learning a heck of a lot more about. I cannot recommend the book Fiber Fueled enough, if you want to learn more about the importance of fiber in your diet. In addition to that, fruit is loaded with vitamins minerals, antioxidants, and phytochemicals: it’s just a powerhouse.

The confusion of people saying fruit leads to (number one) blood glucose spikes; but also people also say that fruit leads to insulin spikes, and it's going to then result in weight gain, and it's problematic, so (they assume) “ I should not eat fruit”. This could not be further from the truth. Like we said earlier, it's the foods that you ate prior, which have set the stage for insulin resistance, and make it challenging for your body to metabolize the glucose in fruit. It's not the fruit's fault. 

Now, we can look at the research and glean some insight into what happens in an actual, low fat environment. One of my favourite studies to talk about was published in the New England Journal of Medicine by Dr. JD Brunzell. He had 22 subjects, and he fed them a weight-maintaining control diet for 8 to 10 days. It was 40% of calories from fat. Then he fed them a weight-maintaining low fat diet for 10 days. This low fat diet was 0% of calories from fat. The only way to have a 0% fat diet is to make sure it's processed. So he fed them 85% of calories coming from carbohydrates, which was dextrose, and 50% of calories coming from protein, in the form of a protein powder. This is literally a sugar water solution. That was the 0% fat diet. What he found is that number one: fasting blood glucose levels decreased uniformally. There was no exception. It decreased by 9.6% in the patients who had diabetes. But more importantly, he did a paired, oral glucose tolerance test. The subjects were told to consume a 75-gram solution, and they had their blood glucose levels and their insulin levels tested, every 30 minutes for three hours.

At every single point in the test (the comparison); remember these are the same individuals. The same person did both diets. At each point, when they were on the low fat diet (0% of calories from fat diet), their insulin levels were lower and their blood glucose levels were lower. This should not be possible. You have to stop and pause for a second and think about that. Wait a minute. I don't care what diet they did previously. I don't care what you're comparing it to. If human beings it drank nothing but sugar water, they should become more insulin resistant. They should have spikes in their insulin levels and their blood glucose levels should go higher. That's not what happened. There's a laundry list of research showing the same thing. This study, the author concludes, this data suggests that high carbohydrate diet increased the sensitivity of peripheral tissues to insulin. Again, I'm not advocating that people consume sugar water and that sugar is good. The point is that if you look at the research, you will find that any time carbohydrate-rich foods are fed in a low fat environment, there is no problem to be spoken of here. The people who are citing research are saying, "Oh, you know, fruit did this or fruit did that, or carbohydrates caused this." It's invariably looking at the consumption of these foods, in a high fat environment. That's the problem.

Karina Inkster: When it comes to the plant based diet then, of course whole foods, nutrient dense as you and Cyrus are promoting, have there been other forms of the plant based diet that have been tested with diabetic populations? Do we know anything about a medium fat diet, but it's vegan, in diabetes? I realize that there's probably more ongoing research, but what else has been compared, but as a vegan diet.

Robby Barbaro: That's a great question. Unfortunately there's not enough research happening recently. I don't see enough research being done on plant-based diets in general. I think there's more and more coming out, but it's not enough. I think the bottom line is: I as a coach, just trying to help people achieve the results they want to achieve, I don't really care what version of the plant based diet you do, as long as you are achieving your goals, and you're moving in the direction that you want to go. We always say at Mastering Diabetes: we're not the food police; we're not here to tell you what to do. We're here to help you understand the consequences of your decisions. We have this thing called the decision tree, which is part of the Mastering Diabetes method.

When people fill that out, they document their daily decisions and they can see the impact, particularly on their blood glucose levels. What happens when you have a higher fat dinner? What's your fasting blood glucose the next day? What happens when you have a higher fat lunch? What happened in the rest of the afternoon? What happens to your blood glucose level? You could see this, and you just get to decide what you want to do. How far do you want to take it? What foods do you want to try? We do know that as you consume more unsaturated fat from whole plant foods, you will improve your insulin sensitivity. There's plenty of research showing that, but it's still becomes a question of how far do you have to take it, to get the ideal results that you're looking for. That comes down to a very nuanced day-to-day understanding of what's going on in somebody's life.

The bottom line is yes; somebody could do a higher fat plant based diet and get great results. Especially if you're losing weight; weight loss is huge for improving insulin sensitivity, especially if it helps you be active, if it helps you maintain the diet, if it's something you need just to personally feel satisfied and happy with your food, it's all good. We're not militant about what we've created here. We just know that based on evidence based research that we do have, based on our own experience, and the experience with thousands of clients, we know what leads to maximum insulin sensitivity, hands down, no questions asked, this protocol where you do choose to keep it under 15% will maximize your sensitivity. You could ask yourself the question, "okay, do I need to get to maximum? Is that important for me to get the results I'm looking for, and have great long-term outcomes? That's a decision that people are going to have to make on their own.

Karina Inkster: That makes sense. I like how you brought that up. So many individual things. I mean, the answer usually to anything in nutrition and fitness is “it depends”. Right?

Robby Barbaro: As authors of a book, and looking at research, and trying to guide people, you have to draw the line somewhere and create some principles, but of course, in every individual case there's nuances and there's room for flexibility. The thing I care about the most is something being doable and sustainable and stick for the long term, because anybody can do anything for a short period of time, but we're not looking for short-term results. We want longterm results.

Karina Inkster: Absolutely. Do you think a lot of people do things like the keto diet, or other forms of low carb diets, because it gives them short-term results?

Robby Barbaro: That's exactly right. Chapter seven of this book, we dedicated to that entire concept: comparing short term results to long-term results of a ketogenic diet, versus a plant based diet, and what we know and what we don't know. That's exactly what's happening in the ketogenic world. They do get fantastic results in the short term, but our concern is the long-term consequences. There is no known data about what is going to happen long-term for people who are doing these very new ketogenic diets. There aren’t societies, there aren’t groups of people, there isn't research over 20, 30, 40, 50 years old. It just doesn't exist. It's too new. I have to say; I respect the keto crowd. We have a lot more in common than we disagree on. Anybody who's out there, who's choosing to avoid processed foods, and not eat junk and just actually make the effort to clean up their diet and clean up their lifestyle, kudos. Hashtag, respect. We’re in this together! 

I think the biggest problem in our country is people who are apathetic, the people who just don't care, and aren't trying: that's our biggest problem. But with that said, I respect them. I respectfully disagree with the choice, and want to make sure that people are aware of this other option. I also want to remind people that when a low fat, plant-based whole food diet is executed properly, you also get rapid results just like you do on the keto. If you go point by point, when it comes to weight loss; when it comes to dropping your A1C, reducing medications, we can go toe to toe. It's the same amount! My point is: when you do the plant based version, you also have a long, long list of scientific evidence- long-term and short term-to support your decision, but you're also glucose tolerant.

You get the same benefits and you can actually process glucose, which is important for brain health and preventing Alzheimer's disease. Glucose tolerance is definitely a sign of health if you can eat whole plant foods. I think that's important for people to just know, and particularly in the diabetes community, there are people who just don't believe this is possible. They say, "no way, I can't eat the carbohydrates foods, I get a high blood glucose reading every time!” We're out there, working hard, spreading our message, and webbing the storm of all the people who are yelling at us, to try and just deliver this truth so they can have some options. I have to tell you: the number of people that have come to us, trying to keep ketogenic diets that have come down with really challenging circumstances. I mean, neuropathy becomes an issue. Gut issues end up occurring. We've had people come to us with cardiovascular health issues. One man came to us; he was told he was supposed to have five bypass surgeries, but he decided to try our approach first, and he avoided those bypass surgeries. It's scary what consequences can come about, so we just want people to know about the option.

Karina Inkster: Well, and like you said, there is no longitudinal research right now on keto diets. That's a problem right there, but given what you know about how nutrition works and all the different options, what do you think would be some of the long-term implications or metabolic type complications that could happen?

Robby Barbaro: Honestly, I think one of the biggest, biggest concerns is cardiovascular health, particularly if you're going to choose to consume an animal-based ketogenic diet, that has a lot of saturated fat. We have a long, long list of evidence. I know the crowd is going to go crazy, and argue their side, but: saturated fat will clog your arteries. The number one cause of death worldwide is heart disease, so that includes diabetes. People living with diabetes, they're all up in arms about their blood glucose levels. (They say)” Let me do the ketogenic diet to get my A1C down, and reduce some of my diabetes meds", but they're trading one problem for the biggest problem, which is heart disease.  I think that's the number one thing to focus on. And honestly, if that was the only problem with the approach, it's done. It’s already out the window. That's my biggest concern.

Karina Inkster: That's a really good point. I don't think that's something people talk about a lot, because the human brain is not great at thinking about the future. It kind of evolved in an environment of, "Oh shit, am I going to get eaten by some predator in five minutes from now?" There's not really a whole lot of long-term kind of thinking. That's a really interesting point: people want results yesterday. They want the easy option a lot of the time. Especially when they see other people getting results from things like this, they think "Oh, I should give this a try," but they're not really considering what the other options might be, like your approach, and what the long-term implications could be.

Robby Barbaro: That’s right. That's exactly right. We are not hardwired to think about what's going to happen 20 years, 30 years, and 40 years down the road. We care about what's going to happen now. Again, like we just covered in that same light, you can get some amazing results now, for sure.

Karina Inkster: Good point. That's amazing. Do you have something to leave our listeners with whether they are currently living with diabetes or not?

Robby Barbaro: The best thing I can encourage people to do is go to our website, and fill out our insulin resistance quiz, and see if you are living with insulin resistance. You go to the home page at There’s a little button in the upper right corner. It says, am I a candidate? Fill that out, you'll get your results immediately, and figure out: is this something I should address in my life?

Karina Inkster: Well, Robby, it was fantastic speaking with you. Thank you so much. I appreciate you coming on the show.

Robby Barbaro: Thank you for having me. I really enjoyed it and I hope everybody learned something today.

Karina Inkster: Robby, thanks again for making the time to speak with me. Listeners, make sure you head to to connect with Robby, and to get your hands on Mastering Diabetes, the book he coauthored with Cyrus Khambatta. Thank you so much for listening and I will see you in our next episode!


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