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The Dose Transcript for March 22, 2023

Host: Dr. Brian Goldman

STORIES FROM THIS EPISODE

BRIAN GOLDMAN: Hi, I'm Dr. Brian Goldman. Welcome to The Dose. The Keto diet is one of the most popular diets out there and has been for several years now. Proponents love it, but every so often concerns are raised and that's what happened with the release of a new study. So this week we're asking what do we know about the health effects of the keto diet? Hi Andy, welcome to the dose.

ANDY DE SANTIS: Hi Brian. Thanks for having me.

BRIAN GOLDMAN: How often are you asked about the keto diet in your work as a registered dietitian?

ANDY DE SANTIS: Very regularly in, you know, in different capacities, but suffice to say there's definitely interest out there in the keto diet, what it's about and what it has to offer.

BRIAN GOLDMAN: And it's that popularity that really makes us want to do this topic this week and we're glad to have you. But before we begin, can you give us a Hi, my name is, tell us what you do and where you do it. Just ad lib.

ANDY DE SANTIS: Lib. Yeah, absolutely. Well, my name is Andy De Santis and I'm a registered dietitian from Toronto, Canada, and I have no private practice. A Young and Davisville, and online, I've written several books. Love writing and yeah, love all things nutrition.

BRIAN GOLDMAN: You're the person we wanted to to reach out to. So here we go. For those who don't know which food groups are excluded from the keto diet.

ANDY DE SANTIS: Great question. Generally you're looking at excluding legumes, lentils, chickpeas, kidney beans, foods like that, starchy vegetables, potatoes, sweet potatoes, you know, most fruits in any meaningful quantities, and then whole grains, the quinoa, the rice, the breads of the world.

BRIAN GOLDMAN: So that means no, that basically no bread, no cereals as well, no bagels, pizza?

ANDY DE SANTIS: Certainly, I mean, there are going to be products, you know, keto friendly products that can fulfill those parameters. And you can certainly play with the quantities of some of these foods to make them fit. But you'll you have to be quite, quite crafty to pull that off.

BRIAN GOLDMAN: Yeah. And when you when we're talking about when we're talking about about a keto diet, we're talking about a low carb diet. So as I understand it, less than, you know, give or take, less than 50 grams of carbs a day, which which is something like a bagel.

ANDY DE SANTIS: Depending on the bagel, that's not far away. Yes, it's around that 50 gram number that's usually used as the upper threshold for the keto diet.

BRIAN GOLDMAN: Can you talk about the different kinds of keto diet? Because there's Atkins, you know, there's Paleo. What do we know about these various diets?

ANDY DE SANTIS: Yeah, so it's a great question. I think that there's a few different ways to even look at the different types of of the keto diet. And you can have someone who is trying to pull off the ketogenic diet in a way where they're actually checking their, their blood ketones. You can have someone who is just going for a kind of a lower carb diet under the keto umbrella, whether or not they actually care if they're in ketosis or not. And then you have different iterations within the ketogenic diet itself if you are going to do it a few days on a few days off, if you're going to play around with the the sources of the protein, more plant based protein versus animal based protein, but it really does fundamentally all come down to that carbohydrate number. The fats and proteins can vary. But but yeah, that's you know, they're all like, we're going to get to this. I'm sure in this conversation there are a lot of different ways that someone can pull off a keto diet depending on the nature of their choices.

BRIAN GOLDMAN: But the key thing is if you're stringently reducing carbs, you've got to replace them with something which is either going to be some, it's going to be some combination of proteins and fats, and often it's a high fat diet. Before before we we start talking about some of the nuts and bolts. I wanted to ask you, you know, you've already said that a lot of people ask you about the diet. What's your take on why this diet continues to be so popular?

ANDY DE SANTIS: Yeah, it's a good question. I think there's a there's a few things to it. I think on some level, you know, there's a lot of people out there who quite enjoy the foods that the keto diet emphasizes. You know, of course the keto diet gives you an opportunity to eat perhaps larger amounts of red meat or cheese or other similar products. I think on some level these are well-liked foods that have been, you know, demonized. I don't know if they're demonized per se, but there's some question about the role they can play in your health. And the keto diet kind of opens the door still a little bit on some level. I think that's part of it. I think also because the body shifts to the state of ketosis involves something, you know, kind of novel and unique from that perspective. So I think that's appealing. And I think of course anecdotally, you know, those can be people out there who are doing it and having some success with the endeavor. And I think, you know, friends, family members, online accounts, all of that combined really, really generates. And of course, I think as well, it does exclude quite a few food groups that for some people can be problematic or challenging to navigate. You know, maybe the more refined carbohydrates, the baked goods of the worlds. Not to say that one cannot eat these foods and live a healthy, happy life. Of course they can. But the exclusion of those who is maybe for some people, makes it easier to commit to dietary changes. So I think those are few reasons why it's exploded in popularity over the last decade or so.

BRIAN GOLDMAN: You've already mentioned that the the whole point of the diet is to put the body into ketosis. When does that happen? Why does that happen?

ANDY DE SANTIS: Yeah, so ketosis really is the state of your body switching. From relying on carbohydrates for energy. Right? Which the vast majority of people consume more than 50 grams of carbohydrate a day in their bodies will use carbohydrate first and foremost as energy source. When you strictly and let's say, partially limited amount of carbohydrate you take and then you increase your fat intake instead. Your body will then use that fat which your liver converts into ketones, which are then used as your body's new energy source. And so that's really what it comes down to.

BRIAN GOLDMAN: For most adherents of the diet. Do they actually enter a state of ketosis?

ANDY DE SANTIS: That's a great question. I think that's not the easiest thing to measure. And in my anecdotal experience, just in people that I've worked with, people that I've spoken to, like I said earlier, when we're talking types of the keto diet, I think for the average person, the real question is are you doing a Kito-ish diet to take advantage of the principles of the keto diet or are you really in ketosis? And I think that's the big question. I don't know that we really have data to say how many people pursuing the keto diet are actually ketosis versus otherwise. And I don't know that that matters as much as what they're actually eating under the keto umbrella.

BRIAN GOLDMAN: We'll get to that in just a moment. But you know, there are other ways, physiological ways, that you can experience ketosis that don't involve the diet. Like, you know, I've, I've run a couple of marathons, I've run, I've run some half marathons and, and I think that's one way of entering a state of ketosis, isn't it?

ANDY DE SANTIS: Yeah. And I think the most conventional way that people will enter is probably through intermittent fasting of various lengths. You do get you do get into that realm depending on your what you ate in the period before the fast, how long the fast was. And funny enough, I mean, fasting is another obviously very, very popular trend as well.

BRIAN GOLDMAN: So let's start talking about the diet and some of its benefits. I think one of the reasons for its popularity is that, you know, there are people who've tried other diets and have not lost weight or have lost weight and gained it, regained it quite quickly. How good is a key to diet at helping people lose weight?

ANDY DE SANTIS: Yeah, I think at this stage, you know, whatever people might think about the keto diet on either side, I think we can't deny there is evidence that it is effective for that purpose. There's not a strong evidence that that's more effective than other dietary strategies, but it doesn't mean for someone that we pluck off the street that if it resonates with them, if they, you know, get some, some great joy in pursuing it, that it can't work for them. It certainly can. But there's, of course, those questions that come along with that, as well as to whether that's the best choice or not.

BRIAN GOLDMAN: And and if they are losing weight, do we know why they're losing weight?

ANDY DE SANTIS: Well, it's overwhelmingly likely that, you know, being in the state, you know, sweet ketogenic diet, you know, perhaps being in the state of ketosis, you know, they have very likely changed their caloric intake. It's very possible that depending on how they carried out the ketogenic diet, it may be an enhancement from their previous diet, because a keto diet, you know, could be like a well carried out ketogenic diet could on paper be stronger nutritionally than, let's say a, you know, more mediocre or average diet. That includes everything that's fully possible. Right? The more interesting question, which again we're going to get to, is a really well carried out keto diet versus a really well carried out, you know, inclusive diet.

BRIAN GOLDMAN: When somebody is on the diet, are they actually losing fat or are they losing muscle? What's going on?

ANDY DE SANTIS: Yeah, so that depends. I think much more to do with how it's applied, the rate of change, if they're if they're physically active. So if someone loses a very large amount of weight in a short period, they're going to be a bigger candidate for losing losing some muscle to someone who loses weight more gradually. I think that's true. Independent of the diet type. I don't think that there's any evidence to suggest that a ketogenic diet carried out diligently puts you in a worse position about regarding losing fat or muscle. I think, you know, you have the same potential to lose body fat on a keto diet based on the evidence I've seen as you do on, let's say, a mediterranean or other dietary pattern. I think it depends on, you know, the caloric intake, the physical activity level and then the overall pattern of the diet.

BRIAN GOLDMAN: Self Do you ever recommend the keto diet for an average healthy adult?

ANDY DE SANTIS: Personally, I do not advocate for the keto diet broadly. However, I also respect the fact that on the individual level there's curiosity around it and there are ways to carry out a keto diet that can be, you know, quite strong and quite nutrient dense, but you won't find me advocating for it for the simple reason that my personal belief, you know, which which is stemmed from, you know, my, you know, working with so many people looking you all the research is that nobody got healthier by cutting out lentils and sweet potatoes. This is the line I like to use. And so that kind of represents my view on the keto diet. But that does not take anything away from the fact that some people will pursue the style of eating and have success. And I fully respect that. And my hope is that they can pull it off in the best way possible.

BRIAN GOLDMAN: So if part of that approach is to honor, you know, the client who comes to you and says, I want to try it. Can you help me? What are the what are the rudiments of the keto diet that you think are important, not just for losing weight but for maintaining health?

ANDY DE SANTIS: Yes, of course. Of course. It's about allowing the client to make informed decision. So absolutely, absolutely right in that regard. So I would say, you know, we think with the keto diet, you know, where can we get as much diversity as possible? Because on some level, you know, and I brought this up earlier in the conversation, okay, there may be a draw towards items like red meat and cheese. And I'm not, you know, speaking poorly about those foods at all. Let's say right now, let's just say those are all towards that. But where are we getting our fats from? We have plant based fat sources like avocado nuts and seeds, which can play a role. Where are we getting our protein from? Is it is it is it from red meat exclusively? Are we incorporating fish and seafood and plant based protein sources, perhaps like tofu and tempeh? So for me, it's really about variety, including apple vegetables, because vegetables for the large part, of course, excluding large amounts of starchy vegetables, vegetables generally are fit into a ketogenic diet. But to what extent are they incorporated? Is it minimal? Is it is it is it maximal? All of those factors have a role to play, and those are some of the really, really important foods in a keto diet to pull it off.

BRIAN GOLDMAN: Well, so you're I'm assuming you're not advocating as as happens in some of these diets that people consume a stick of butter.

ANDY DE SANTIS: I certainly would not advocate a consuming a stick of butter, as, you know, a regular health practice. I mean, look, you know, someone can have know I use this example very often. Someone could sit down to a meal of salmon, avocado and kale cooked in butter. Sure. Or cooking, whatever it is. You know, by all accounts, that is a that's a that's a good level meal. That's a high quality meal that fits under the Kojak umbrella. Right. So, you know, and conversely, we can have a sausage dipped in, I don't know, the most robust cheese option and dip some sausage in there that can be under the ketogenic and bread as well. So it's massive variety and how you can carry this out.

BRIAN GOLDMAN: Would you say that maintaining a keto diet requires more planning than some of the other diets that are out there?

ANDY DE SANTIS: You know, I.... Yeah, I mean, yes and no, because, you know, to play devil's advocate, you know, you could say the same thing about a vegan dietary partner that you cannot just jump into that and expect, you know, good health outcomes without diligent planning. So, you know, as a dietitian, as someone who, you know, helps people strategize around nutrition on a daily basis, I will not the keto diet there. I think the keto diet requires proper planning to pull off well, sort of every other style of being too.

BRIAN GOLDMAN: I want to dig into a bit of the research in general. What does the research show about about a keto diet and how it affects the body? We've already talked about weight loss. What about things like blood pressure, diabetes, blood sugar, cholesterol, triglycerides, things like that?

ANDY DE SANTIS: Okay, so there's a few layers here. Okay. So first of all, when we compare the the keto diet to, let's say, you know, there's a recent study in the I think it was the Stanford A compare the keto diet to to a mediterranean diet and look at the outcomes. And what they found is the keto diet was more likely to raise cholesterol, but it gave you a little bit more reduction in triglycerides, for example, as it relates to blood sugar. A well carried out keto diet has a very similar potential to a well carried out, let's say Mediterranean diet to lower blood sugar levels, right? So it really it comes down a lot to the execution. Okay. Which I guess shouldn't surprise anyone based on some of the examples already provided. So the issue is though, and this particular study, which probably won't be a surprise, is that when they looked at people who followed both, they found that when they followed up with them several months later, even the people who follow the keto diet closely in the study period were had diverged from it. Right? So the adherence question is the big difference. And again, that's something that we'll discuss. But you know, a well carried out ketogenic diet has the potential to to offer decent health outcomes or good health outcomes in the medium term, but we don't really know what the long term consequences are. A following a good keto diet for two, three, four or five years. We just simply don't have that data.

BRIAN GOLDMAN: We don't have the long term data. There was a recent observational study that triggered our interest in in talking about the keto diet this week. You know, this is an observational study out of B.C. that found that the keto diet may be linked to higher rates of heart disease and cardiac events. Now that's that seems to be contradictory to what to what you've just been talking about because if you have, you know, for instance, if the diet can can reduce triglycerides and can have a positive impact on type two diabetes, reduce insulin resistance, then then it should be reducing the risk of of of cardiac events.

ANDY DE SANTIS: Great point. So the key word and the key aspect of that particular study, what it was, it was a what they call a well formulated keto diet, which means doing the keto diet in the best way possible. So there is mass variability. Again, this is, this is part of the most important point of today's discussion. There is massive variability in how one can carry out a ketogenic diet just as easily, You know, in regards to that particular study and the higher heart disease risk, again, the ketogenic diet can be a source of a large amount of saturated fat if one is dipping heavily into high fat dairy products, heavily into red and processed meat, a large amount of saturated fat, in the absence of other important components can certainly increase heart disease risk via in part increasing LDL, what they call bad cholesterol. So those study findings don't surprise me because I'm quite confident that on the whole, just like any other diet, the majority of people are not carrying out the keto diet in the most optimal way. I feel pretty comfortable in saying that.

BRIAN GOLDMAN: I want to talk for a moment about some of the initial symptoms. Like like I want to know how you feel when you when you start a keto diet. Because I've heard that people become a bit fatigued, they get headaches, they suffer something called brain fog. Can you talk a little bit about that?

ANDY DE SANTIS: Yes. So what you're referring to, I think, you know, colloquially is referred to as the Keto flu. Okay. So it's something that can occur in the first few days, maybe the first week someone's adapting as their bodies energy systems are changing from, you know, carbohydrate fuel to, let's say, fat fueled, you know, a bit of oversimplification to more or less. That's what's happening. So those symptoms are normal and they generally do resolve. Now, if those if those symptoms persist in anyone pursuing it, that's something to to take note of and maybe do reevaluate how it's being done or whether it should be done at all, quite frankly.

BRIAN GOLDMAN: Is there any way of knowing if if a keto diet is doing more harm than good? Are there symptoms that a patient can experience? Do they need to be monitored by their doctor for blood testing?

ANDY DE SANTIS: Yeah, so I think I think there's both short and then medium term ways to, to, to view that. I think in the short term, you know, the keto diet has the potential because it does reduce a lot of foods that contain fiber. I get it, it reduces. I mean reduces eliminates whole grains for the in large part. Fruits, legumes. There is potential it's this is not a guarantee depending on how it's you know there's massive potential for a big fiber reduction. A big fiber reduction can lead to interference with bowel movements and bathroom habits. Constipation might be a sign that something's not quite right. That's something in the short term, you know, a lack of a persistent lack of energy, again, could be another another factor in the medium and the more medium term, you know, what are your what's the bloodwork showing cholesterol shooting up? How is blood sugar looking? I mean, you know, if well carried out blood sugar has great potential to to go down you know with the ketogenic diet but it does have potential go down with any well-planned diet as well, though. Right. So I would say short term constipation could be a big one. And then medium term LDL cholesterol, cholesterol levels, you know, those are two little snapshot things that keep in mind.

BRIAN GOLDMAN: Got it. Okay. So I know you don't advocate for the diet, but there will be listeners who want to give it a try. So if somebody is interested in pursuing the keto diet, how can they go about it as safely as possible?

ANDY DE SANTIS: I would say that, you know, you, you, you know, prepare, prepare accordingly, be diligent whether that means. You know, it's hard to say to do ample research because, of course, you know, you know, to go online. It's you know, there's a lot of content out there and not all of it's good. I would say think about your fat sources again, I'm going to bring this point up. Okay. Are you getting things like nuts and seeds and avocado foods that have unique components are not found elsewhere? Are you getting diversity in your protein intake? Are you relying only on red meat? Are you able to incorporate plant based protein sources? Are you able to incorporate fish and seafood? Now, of course, fish, which some people know some people don't, is pretty much the only rich source of certain types of omega threes, the only very rich source of vitamin D3 for the most part. So there are unique qualities of of foods that can be eaten on the keto diet but could be avoided. So you really want to make sure that you're getting as much variety as possible. The keto diet inherently is restrictive, but within that restriction are you pursuing the utmost variety? And if you need professional help to do that, you know, perhaps pursue that as well.

BRIAN GOLDMAN: Which would mean talking to a registered dietitian? I would hope so. I would do instead of keto. What are the other alternatives? What do you usually recommend for people wanting to lose weight or improve their overall nutrition?

ANDY DE SANTIS: You know, for me, trending towards a more Mediterranean style of eating, you know, seeing the totality of the evidence, understanding that for most health conditions, foods like legumes, fruits, whether it's high blood sugar, high cholesterol, they really help. They tend to be high in the nutrients that people fall short in. So a more Mediterranean diet, which emphasizes seafood, emphasizes legumes, emphasizes fruits and vegetables, that is the dietary style. You know, obviously with customization for the individual that I have the most faith in based on everything that I've seen, it's also, you know, it's more likely to be sustainable because it does not exclude anything, right? It may have parameters that need to be followed, but there's no exclusion. The keto diet inherently excludes the fast, you know, you know, in all seriousness, excludes the vast majority of foods that exist. And there's certainly pros and cons to that and probably more cons for, you know, for most people.

BRIAN GOLDMAN: And finally, for people who do want to give the keto diet a try, are there some specific take home, no nos or pitfalls that you want to make sure stick in their minds that they avoid so that they can stay as healthy as possible?

ANDY DE SANTIS: Yeah, I think I would reiterate my my earlier messaging is don't, don't pigeonhole yourself in terms of your your dietary choices. You know what I mean? I think on some level, if someone's following a keto diet, it's it's inevitable they will eat, you know, almost inevitable anyway. They will eat more foods that have saturated fat because you have to eat something on a keto diet but do not lose sight of vegetables should and must be emphasized. They have to be, you know, for good health at every context. But let's say especially on a keto diet and the best thing, the best thing I could say is think of things on a spectrum between plant and animal sources and try and find yourself in the middle. Do not over rely if you're an omnivore following the keto diet, don't over rely on animal sources of food. You know obviously nothing wrong with those foods. They have a role to play. Obviously they will play a role for mostly on the keto diet, but do not neglect foods of a plant origin. Fancy way to say nuts, seeds, vegetables, avocado, not to keep repeating them, but those are the key foods one can eat of course. And so try and find a middle ground. And if you do that, there's a good chance that you can carry out, you know, a balanced, a strong dietary pattern. And again, there's nuance there. There's personalization there. There's a question of how long that will last, which we can't answer today, of course, because it's all individual dependent. But that's that's the advice I would give.

BRIAN GOLDMAN: Well, Andy De Santis you're a fund of knowledge and I'm glad we spoke to you.

ANDY DE SANTIS: Thank you for having me on. I greatly, greatly appreciate. It is a great job.

BRIAN GOLDMAN: Andy De Santis is a registered dietitian in Toronto. Here's your dose of smart advice. The keto diet is a popular weight loss diet. There are several different kinds of keto diets. Most aim to reduce total carbs to less than 50 grams a day, which is roughly less than a plain bagel, along with around 165 grams of fat and 75 grams of protein per day. That means breads, cereals, pasta, rice, potatoes, corn and other starchy foods are out and high saturated fat foods like fatty cuts of meat, processed meats, butter, nuts, seeds, avocados, plant oils and oily fish are in the diet works by inducing ketosis, the state in which the body breaks down protein and fats to replace the glucose you need for bodily functions. Ketone diets have been shown to promote short term weight loss and to decrease insulin resistance and blood pressure. They may also help reduce the risk of Type two diabetes. The observational study we talked about shows an increased risk of heart problems, which is likely due to an increase in dietary fat in some keto diets. The long term health impact is largely unknown. Keto diets can be. Hard to maintain. Restricting carbs can cause the keto flu symptoms, which include hunger, fatigue, headaches and brain fog can last for up to several weeks. In general, should you give it a try? You should go back to a more balanced diet once you reach your desired weight. The most important thing to do is to monitor your intake of highly saturated fats and to aim for balanced nutrition. Instead of consuming sticks of butter and lots of processed meats and cheeses. Try healthy fats like avocado nuts and oily fish. If you have topics you'd like to discuss or questions you'd like answered, our email address is the dose at cbc.ca. If you like this episode, please give it a rating and review wherever you listen. The dose was produced this week by Stephanie Dubois. Our senior producer is Colleen Ross. The dose wants you to be better informed about your health. If you're looking for medical advice, see your health care provider. I'm Dr. Brian Goldman. Until your next dose.

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What do we know about the health effects of the keto diet?- Transcript

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