A lot of bodybuilders use this diet. As a carb burner, in the absence of carbs, your body defaults to using muscle for fuel. But, as a fat burner you always have a source of fuel, a ‘pantry on board’. So, this is essentially a muscle-sparing diet. Can you elaborate?
When you eat carbs, you can’t burn your body fat. That’s an important link to put it all together. If you’re a carb burner and you’re always eating carbs, your insulin goes up and insulin tells your body not to burn fat.
To put it another way, protein comes first. Protein is the most important thing in the diet. To me, protein comes first and then you can run your body on sugar by eating sugar and starches (which get digested to sugar), or you can run on body fat. It’s really your choice, depending on what you choose to eat. You can’t access your fat stores, and in fact, you can grow your fat stores on a typical American diet, because you’re consuming too many calories, too many carbs, which makes your insulin go up. Insulin then tells your body to store fat and not burn it. So, a keto diet is protein-sparing, because on a keto diet you’re getting protein.
Historically, in the weight loss world, doctors used to lock up people on the ward and put them in the hospital to lose weight! You can imagine that that’s very effective, because you just don’t feed people! The problem with that is that the muscle started to be used to supply sugar. They weren’t eating any food, so the body would scavenge muscle to provide sugar. (Some of the amino acids in proteins – including muscle proteins in the body – can be converted into glucose.) Now, it’s not that you have to eat sugar – that was a confusing thing – but, you need to supply protein (which can be turned into sugar in the body).
A keto diet is protein-sparing, because of the fuel you’re using, yes, but also because you’re getting sufficient protein. Jeff Volek started research at the same time as us at a different university. He started studying the keto diet with exercise and actually found that you could gain muscle mass while losing fat mass. So, while you were losing body weight, you actually gained muscle mass. Nobody thought it was possible, but when you just step back, losing weight means you’re losing fat weight, not muscle weight. If you’re exercising and getting sufficient protein, you can actually gain muscle weight and lose fat weight. Now, if you’re just thinking about weight loss, don’t worry about that – the muscle will take care of itself on a keto diet and you’ll lose body fat because you’re a fat burning machine.
Is there a basic formula for the ideal amount of protein or daily protein intake?
There are lots of basic formulas for the amount of protein that someone should eat. I don’t know if any of them are adequate or correct. It’s like boiling down a one-size-fits-all, which we’ve learned is not a great way to do it. Although, one way to adjust the amount of protein is per kilogram. In the pediatrics world (child medicine), they dose medications based on how large the child is. So it’s a milligram per kilogram sort of dosing, which makes sense. If you have a 50-pound child, they won’t need as much medicine. Once someone becomes an adult, suddenly we stop thinking about the amount of protein per size of the adult.
Protein is another thing I hope I’ll convince you not to worry about too much. If you take a test (in medical education, for example), the answer is that you need at least 0.8 grams of protein per kilogram of lean body mass, which means that you can’t use your total weight on the scale if you’re obese for this calculation. In the weight loss world, and as we teach our students, we teach 1 to 1.5 grams per kilogram of protein per lean body mass, while someone’s losing weight. (Note: this is grams of protein, NOT grams of a protein-rich food by weight on a food scale. Grams of protein in a food are not the same as the grams of food by weight.)
I don’t think these formulas apply correctly to everyone. I have people coming and using apps and formulas and they’re so worried. Sometimes other practitioners have told them to calculate things and you get into these weird situations where the app is telling you to eat more protein when that puts you over the caloric limit, so you can’t lose weight. Or, there’s fear about eating too much protein so that your blood glucose will go up and you get knocked out of ketosis. In my teaching, I don’t have people calculate protein at all and it works just fine. Those formulas are still out there and I know lots of experts use them in a clinical setting, but once I teach people what excellent nutrition is, I don’t have them calculate the amount of protein in the diet anymore.
If someone is doing intermittent fasting, how do they get all the protein they need in one meal?
It depends on what you mean by “intermittent fasting.” If you mean that you’re eating one meal a day and you’re not hungry, I think that’s fine. But, there are all sorts of strange versions of intermittent fasting. Governmental groups studying intermittent fasting are studying diets with carbs in them. Imagine one meal a day with carbs and then you are told not to eat the rest of the day even if you’re hungry – that goes against all of my teaching. I don’t prescribe intermittent fasting if there’s hunger. I teach you to feed hunger, but just a little bit, and over time, it fades away. More studies need to be done on how much protein you get. The best studies we have date back about 15 years, when people were put on a research ward and told just to eat a low-carb keto diet with as much food as they wanted (this is with people with diabetes). Of course, people wanted less food. They ate less, their diabetes got better, they lost weight, and they matched the amount of protein they ate pretty much based on their size. As long as you take away the apps and the calculators – your body is pretty smart and can figure it out.
I still do a lot of work to help people unlearn what they’ve been taught – unlearn the idea that you have to eat if even you’re not hungry (this includes social eating). Back to your point, am I worried about the amount of protein that someone gets? No. One of the reasons is because I think there are adaptations that happen that go beyond our current understanding of the science. We haven’t really studied one meal a day or one meal a week in humans, and this needs to be done. The reason I say that is because one of the shocking things I learned – in your country, in South Africa – is that lions eat once a week. Do you really think I need to convince someone to eat some kind of protein every day and worry about how much when they’re trying to lose weight and they’re not hungry, when some animals only eat once a week? These lions are whittling away to nothing – they run and capture their prey. I think there’s a lot we don’t understand.
As a consensus low-carb researcher, we go to meetings and we say, ‘You intermittent fasting people don’t have data published in peer-reviewed journals,’ or, ‘You carnivore people don’t have the data published yet,’ and while that’s an important thing to be done, we certainly don’t see people wasting away. An obesity medicine specialist can measure your body protein and show you that you’re not losing it as you’re doing these kinds of things. I guess I’m at that point where as long as you’re measuring the protein in your body and you’re in a program that’s teaching you how to eat correctly (meaning low carb foods), I’m not too concerned about that. But, if you’re just going to go out and do this on your own, where you’re maybe having sugar at night and calling it fasting, you’re not getting any protein and that’s not good, don’t get me wrong. Protein is the most important nutrient we need. Protein comes first, but I don’t know how much people need when they’re trying to lose weight.
You mentioned bodybuilders – this is an area that I don’t know a whole lot about. I read books like Lyle McDonald’s, The Ketogenic Diet, which has the history, the oral tradition of the use of low-carb diets in the bodybuilding world. These folks are generally monitoring their muscle mass, not only by size and inches and strength, but by the amounts they’re having. I think that’s a different beast. Remember, my perspective is coming at this helping people achieve therapeutic goals like fixing obesity, diabetes, high blood pressure, and in that case I don’t worry too much about the grams of protein. Of course, some people confuse the gram, the weight of a food, with the grams of protein in it. You have to be careful, because the weight of a chicken breast on the scale is not how much protein is in it. If you’re going to be calculating these things, you need to have a deeper understanding about how to measure protein.
Is it possible for somebody with type 2 diabetes and obesity to over-consume protein?
Yes, but it’s not very likely if you stick to eating real foods, like meat, poultry, fish, shellfish, eggs, some cheese, a little bit of vegetables and leafy greens, because these foods don’t raise the blood sugar much. One of the roles of insulin is to help protein get into the cells. We think of insulin as just a blood sugar hormone, a glucose hormone, and a fat-storing hormone, but it’s also a hormone that helps amino acids into the cells, so there is a little bit of a rise in insulin after eating protein, but not to the same extent as from carbohydrates.
If you’re doing a keto diet zealously, and measuring your blood ketones or breath ketones (I don’t recommend measuring these for everyone, especially when you’re just getting started – keep it simple), you may find that if you’re having protein shakes or manipulating the type of protein beyond what your fullness is telling you, yes, the protein amount that you have can interfere. But, it’s unlikely if you get the proper teaching, eating a mainly real-food type of low-carb/keto diet.
Lucy asks: ‘I only eat one meal a day. Should I focus on protein and how much protein can your body cope with in one meal?’ I’ve always understood that your body can’t process more than about 20 to 25 grams of protein in any one meal. Do you know anything about that?
Eating one meal a day is fine if you’re not hungry and if you’re getting sufficient food – to me that’s proteins and fats. There is no essential carbohydrate, so I don’t worry if someone is not eating carbohydrates, starches, or sugars. I don’t know the research on the amount of protein that you can consume and then absorb – I’ll bet it’s never been studied under circumstances of low-carb diets or intermittent fasting. You have to think, when you’re eating, it’s not like you’re putting food in an I.V., into your vein, which then comes and goes. You have this reservoir called a stomach. Of course, for those who still have one, if they didn’t have weight loss surgery. I see a growing number of people who’ve had weight loss surgery and then yes, they do need to address the lifestyle change eventually. But, assuming you have an intact stomach – by the way, most people don’t need gallbladders though, they’re going to do fine on a low-carb diet, don’t worry about that either – I’ll bet there are differences that happen, adaptations. I’ll bet you’re more efficient in absorbing protein. This is a hunch, but I just say that, because there are certain things that are becoming dogma, based on the science that’s been done. The science that’s been done has pretty much always been under the context of people eating carbs at the same time. Your body becomes more efficient. Some people are concerned about a lowering in metabolic rate. I’m not. That’s your body becoming more efficient. Don’t worry too much, as long as you’re feeling well, you have sufficient strength, and you’re able to do what you want to do.
If you want to do that hundred-mile bike ride, Glen, you’re gonna want to have higher functioning than one of my patients who is just trying to go up two flights of stairs. There are all sorts of different types of activities we’re trying to support. A big issue is in what area we are talking about. Again, my perspective comes from helping people trying to achieve medical and health goals, not optimizing (athletic) performance, for example.
Ben asks: ‘Should you include protein with every meal?’
That’s a great question, because how many meals should you have? If you’re just having one meal a day… So that’s a great question. I don’t think so. I’m pretty flexible. Once you’re a fat burning machine, you’re going to find that you have less urge to consume energy, because you’re burning your body fat so well. The idea that the stomach is like a pot on the stove and if you eat even a couple hours apart, you may be actually just adding to this pot, or it’s a helping, you’re digesting a meal over many more hours than you think, between breakfast and lunch for example. It’s not like the food has disappeared yet.
Keegan asks: ‘I typically aim for a higher protein intake and use a protein powder to get my daily quota. What are your thoughts on protein powders and do you have a particular preference?’
I hear in that question that you get a protein goal, and I was just trying to dismantle the idea that we know what the goal should be. Protein powders, as long as they have no carbs and just from the first dial on the sound modulator (introduced in my book End Your Carb Confusion), the most important thing is how many carbs are in the protein. I think that’s going to be across the board – you want to just look at the protein powders that are low in carbs, but I don’t think you should just have protein from protein powders. I’m not really sure if that really adds anything to the protein that you’re going to get from the real foods that you eat. I know these are sold all the time as giving you more energy and making you stronger. In your experience, Glen, when you’re trying to optimize performance when you use something like protein shakes, do you have better performance?
The caloric needs of people who do bodybuilding and Crossfit are going to be slightly different to the average person. One of the things that we typically hunt for, is a higher protein type diet. For example, if I am trying to shoot for 120 grams of protein in a day, it’s very difficult to get in without having the occasional protein shake. Keegan did not mention that he is a bodybuilder, but I would imagine that he possibly could be or he could be an athlete and he shoots over a higher protein daily amount, which is very difficult to get if you’re eating real foods. As you and I know, you’re not going to be eating because you’re hungry, you’re going to be eating because you’re trying to gain a particular macronutrient. With a whey protein, you can have two scoops of protein powder twice a day and it’s just like drinking a glass of water, it doesn’t really make you full or give you the satiation that you would get from eating meat, for example.
I wish there was a way on the internet – and I guess we’re doing that with Adapt Your Life, where you say, ‘Caution! This does not apply if you’re talking about high-functioning athletes. The internet doesn’t come that way.
The good news is that we will do deep dives with courses, explaining these concepts to people.