Hi, I'm Wendy Zuckerman, and you're listening to Science Versus. This is the show that pits facts against a lot of fat. On today's show, The Ketogenic Diet. This is the diet where you have to eat a bunch of fat and almost no carbs. It's been booming for years now. Online, people just love it. Wow, this is amazing. This is like a medication, but better. The biggest benefit is cognitive. I'm more awake. People say that it helps them lose weight, makes them run faster, be stronger. We're hearing that it might even help with some serious mental health conditions. But it's not just folks on socials that are getting excited about the keto diet. Scientists are as well. If a drug did everything that the ketogenic diet did, it It would be an enormous blockbuster drug worth billions of dollars. That's Dom D'Agustino at the University of South Florida. He didn't start researching diets. No, Dom is a neuroscientist, a brain guy. But when he started reading about this weird ketogenic diet, he just got so intrigued that he had to try it. Dom says that after a couple of weeks... I could go throughout the whole day with a lot of energy, and I could go to work, forget about eating, and bang out a whole day of work.

I almost owe my career in some ways. I don't want to make this sound like a stretch of the imagination, but I'm not sure that I would be able to achieve the productivity that I achieve to be able to get tenure because I push myself in ways I never thought I would be able to push myself. And this all made us at Science Versus very curious, especially me and producer Kaitlyn Soare. I would love that. Yeah. I'm incredibly unfocused. I'm like a tiny puppy. It's like, What's this over here? Because that is the promise that is… The idea that who we are now is just one version of ourselves. When we go on this diet, we'll be on this new and improved version of ourselves. Blat Jarelle, our editor at Science Verses, is going on diet with us, and she was not as excited as we were. It sounds like nonsense to me. Yeah, I just want to be really super honest with you guys. I'm a skeptic, and maybe I'll be wrong. The truth is, though, once we realized exactly what this diet entailed, none of us were particularly excited. Kaitlyn gave us the rundown.

Most Westerners eat about 50% of their calories from carbs. We need to get that down to 5%. Yeah. So going on keto means slashing carbs and sugars. No croissants, no pasta, no cake, no beer. You can't even eat much fruit. It's depressing. So with all this stuff that you can't have, how do you up your fat game? Am I just having sticks of butter, cheese, avocado, nuts, eggs? You can make an omelet, put some mushrooms on top of that. All right. Like fettucini, but with a little bit of olive oil. Absolutely not. You can have the olive oil. That's it. It would be so easy for this to go horribly, horribly all right. Someone said rye. No, no one said rye. Instead of beautiful fresh bread, I'm going to be eating slices of cheese with the Vegemite for breakfast, fistfuls of almond for second breakfast, butter in my coffee for third breakfast, and the rest of the time, salmon with heaps of olive oil. Now, here at Science Versus, we first ate up the science on the ketogenic diet several years ago, but we've updated the research, which has been booming in this space. And so today, we are going to find out, one, can going on a ketogenic diet really improve your brain and even boost your mental health?

And two, what can this diet do for your body? Can eating all of this fat help you lose weight? When it comes to the ketogenic diet, there's a lot of stuff that sounds like nonsense. But then there's science. Science Versus the ketogenic diet is coming up just after the break. Before that, a quick word from my mom. When I told her that we were doing this little experiment, She was not impressed. It's a sample of one. The whole team, the team is doing it, so it's a sample. A sample of three. Wow. Science versus team is going to do a whole new experiment on three people. They might as well drop the clinical trials. Sick burn, mom. Appreciate the support. We're also going to read stuff like scientific papers. It's season three of The Joy of Why, and I still have a lot of questions. Like, what is this thing we call time? Why does altruism exist? And where is Jan 11? I'm here, astrophysicist and co-host, ready for anything. That's right. I'm bringing in the A-Team. So, brace yourselves. Get ready to learn. I'm Janna Leven. I'm Steve Strogaffs. And this is... Quantum magazine's podcast, The Joy of Why.

New episodes drop every other Thursday, starting February first. What does the AI revolution mean for jobs, for getting things done? Who are the people creating this technology? And what do they think? I'm Rana El Kalioubi, and I'm an AI scientist, entrepreneur, investor, and now host of the new podcast, Pioneers of AI. Think of it as your guide for all things AI with the most human issues at the center. Join me every Wednesday for nine years of AI. Don't forget to subscribe wherever you tune in. Welcome back. There are all these claims out there that the ketogenic diet can make you a smarter, healthier human. So we tried it out. Okay, so it's day one of my attempt at the ketogenic diet. And how did I I did bad. Terrible. There's one solitary Oreo in my house, and it was just winking at me for hours. So I gave in and ate it. Okay, it's day two attempt at the ketogenic diet. It's 5:00 PM, and I have one gram of carbohydrates that I'm allowed to eat today. And there is nothing in this house that I can eat, and I'm hungry. We've got olive oil.

I can eat a teaspoon of olive oil. Oh, Jesus Christ. That's not... Okay, but the reason that we are going to stick with this diet is because while a lot of diets out there promise big things, what's different about the ketogenic diet is that it didn't start out as some hashtag on TikTok. Keto actually came from science. Nerds came up with it in the 1920s, and it was actually created to treat kids with epilepsy, which is how our neuroscience scientist, Dom D'Agustino, first got interested in it. He was studying seizures when he stumbled upon this diet. I was shocked to actually see that the ketogenic diet was actually used for epilepsy. It's so counterintuitive. What were you thinking? What a diet is stopping people having seizures? Well, I didn't believe it at first, and I pulled every article I could find about the ketogenic diet, and I spent two weeks just immersed in reading this research and realized that it was actually real. We think that this might be happening because of this pretty cool thing that the ketogenic diet can do to your brain. Okay, so When you cut off your body's supply of carbs, aka sugars, your body basically thinks that it's starving, and it starts to use the fat that it's been storing on your bum for a rainy day.

Now, your brain can't directly use fat as energy. So instead, that fat heads to the liver and gets turned into this thing called ketones. Your brain happily slurps up those ketones, which is something that really surprised Dom. I was basically thought the brain could only use glucose for fuel. So this was completely new to me. And the fact that your brain is now using ketones as a fuel source, that could be the reason that some people stop having seizures on this diet. We're still working out exactly why that is. It could be because ketones can help neurons communicate with each other better, or perhaps because it's sparking up chemical messengers in your brain. Or maybe it's because for some people, their brain just doesn't work so well on glucose. So switching up the fuel source makes the machine in your mind work a little better. Dr. Shabani Sethi at Stanford Medical School says, If you think about your brain like a car that's not running that well. If you think that maybe your car is a bit old and it's not as responsive to you with the gas and the break, what a ketogenic diet is doing is making that system more efficient.

I've never actually explained it this way, but I think it makes sense. Okay, great. I love it. It is pretty wild that just cutting out carbs and eating a bunch of fat could change people's brains for the better, at least when it comes to epilepsy. But now, there's tons of claims that this diet can do way more than that. For example, headlines have been popping off with this idea that keto can help with your mental health and that it can work wonders for those with bipolar and schizophrenia. This is actually what Shabani has been looking into. For her, this all kicked off several years ago when she saw something pretty intriguing. A patient that she was helping to treat who had really nasty schizophrenia went on this diet and seemed to get better, and Shabani was shocked. Actually, I was very skeptical. I didn't believe it, and I essentially She eventually ended up interviewing many people in the family to that patient to really understand, is this actually real? After that, she wanted to know if this could be real for other patients, too. Several years ago, Shabani and her team got 21 people with schizophrenia or bipolar, put them on the ketogenic diet for four months.

These were patients who also had metabolic issues, like obesity or prediabetes. They go on the diet, and Shabani is measuring a bunch of stuff, like their blood sugar, but also what was happening to their mental health. What their mood was, their energy level. Was there any paranoia or fear, anxiety, hearing voices. At the end of her trial, here's what she saw. Over 79% of the participants, they had a clinically meaningful psychiatric improvement, according to the scales. They had a clinically meaningful improvement. What would that look like? There was a patient who was also an engineer and was very well aware of their symptoms. He had schizophrenia. He would get paranoid and have these hallucinations where he heard footsteps and saw trash cans moving around. But then after going on the keto diet… He noticed a change in the paranoia per day and also visual hallucinations per day. He said initially it got a little worse over the first two weeks, and then it got significantly better to the point where he noticed that when he had a higher ketone level, that His clarity and his mental energy improved and the amount of times that he saw per week, a trash can't move, decreased.

In Chabani's paper, which came out this year, they describe another patient who said that the diet saved their life. I would not be here today if it wasn't for keto. Shabbani thinks that maybe, like with epilepsy, the brains of these patients just worked a bit better when they were fueled by ketones. But we're not really sure how this is working. The diet also seemed to help with the patient's metabolic health, and so that might have made a difference for their mental health. Overall, Shabbatny is cautious. This It was a small trial. There was no placebo control. She wasn't comparing it against other drugs. But still, based on this early data, she is excited. I was surprised that something like that could change in the brain from a diet. I know I'm saying diet, but I really believe that this is more than a diet. Researchers aren't just looking into schizophrenia here. Other small trials suggest that a ketogenic diet might help folks with Alzheimer's and Parkinson's disease. This is all rather intriguing, but it does bring up this huge question. What about people who don't have schizophrenia or epilepsy? What if you're relatively healthy? Can the ketogenic diet boost your brain?

Just like swathes of people online are saying. Well, the only studies we have on this are in mice and rats, which are actually pretty promising. The ketogenic diet seems to help them remember mazes. Even though we really have no idea whether this does supercharge a healthy brain, Shabbatny actually thinks it's plausible. We don't really know how healthy we are in the brain. If we don't have a mental illness, we don't really know it's actually how much inflammation do we have, how much are neurons firing? As for science versus, how did our brains go? Well, after a couple of weeks on the diet, no bread, no beer, no bananas, we sat down to talk about how we were going. Here's our editor, Blyb. If you guys remember, I was seriously, I was super skeptical. I thought this whole thing was basically pretty dumb. But I have this thing where every afternoon at three o'clock, I'm like, Okay, got to get through the rest of the day. Got to power through. I get the three o'clock sleepies and whatever. That It disappeared completely, I swear. I feel ridiculous even saying that. But I did not get sleepy in the middle of the afternoon.

I could just keep going. I was like, Okay, great. I have ideas about this. Okay, let's have another meeting about this. Okay, I'll stay until seven and work on this other thing. It was- It was your brain on keto. Was better. My brain on keto actually felt better in a way that absolutely shocked me. Wow. Yeah. Katie, how was your experience? I didn't feel that. I'll have what she's having. Exactly. Katie and I didn't get our super-charged keto brains. Maybe it's not surprising when I tell you what happened several months later. Kaitlyn, sorry, are you still on the ketogenic diet? Hell, no. Wendy, are you on the diet? Hell, no. Lydhe Tarrell, are you still on the diet? I am still on the diet. You guys. I know. Wow. Yeah, I I'm as surprised as you are. I really did start to feel better. Then I was like, If I go back, what if everything changes? I was afraid to go off of it. But you have kept this under wraps. Yeah. I'm a little embarrassed about still being on keto because it feels dumb to stick with something where I'm like, There's no reliable evidence.

Even if it is my experience, I have a hard time trusting it. What if it's fake? What if it's all in my head? It just has turned my world upside That's why I haven't told you guys. After the break, can eating bucket loads of fat actually help you lose weight? Plus, what are the risks here? We learned them the hard way. Itchy welts. Your entire body is just this one big rash. It was horrible. Welcome back. Katie and I have given up on this diet, but Blythe is still at it. The next thing we're going to look at is weight loss. Funnily enough, we all lost a little bit of weight on this diet, even after just being on it for a few weeks. And weight loss seems to be one of the biggest reasons that people go keto, which is counterintuitive, right? How can you lose fat by eating more fat? To find out, we called up Louise Burke, a professor of sports nutrition at Australian Catholic University. Louise has spent her career telling people what to eat, which is a pretty tough job. We seem to have this fallibility as humans that we've just got to find ways of putting garbage calories in our mouths.

Because it's so tasty, Louise. I know, but this is the problem. So could the ketogenic diet be a solution, something that stops us from putting garbage in our mouths? Louise says yes. Look, some people have had some success using it to lose weight. There are studies showing that people can lose a lot of weight on keto, sometimes more than 10 kilos or 22 pounds in a year, though that is on the upper end. During the first year that you're on it, the ketogenic diet does seem to work a little better than other diets when it comes to losing weight. Like, if you compare it to low fat diets, over a year, people on keto tend to lose 2-3 pounds more. But the question is, how does this diet help you lose weight? Well, one idea is that going keto does something special to your body. It turns it into this better fat-burning machine. There is a little bit of evidence that suggests on a ketogenic diet, it does tweak your body's metabolism. Some studies also suggest that maybe ketones are tamping down your appetite, but there's a bit of a debate to that. But Louise says that if you're losing weight on this diet, it could be for a really simple reason.

When you cut out all of your favorite foods, you just can't treat yourself the way that you normally would, so you end up eating less. The way that most people lose weight is that they eat fewer calories by restricting the number and range of foods that they can eat. Whether it's a diet that says you can only eat apples on one day and cheese on another day, et cetera, or whether it's a paleo or a keto, once you start reducing the range of foods that people eat, that diet will lead to weight loss. And Blyve, who ended up losing about 6 pounds, which is a couple of kilos, said that this is probably what happened to her. We were throwing Doritos in the trash and couldn't have... There's a particular type of gelato. There's a dark chocolate with chocolate chunks in it. This type of gelato that I really liked. In the bin. In the freaking bin, Wendy. And there just weren't many super low carb treats that I was like, Yeah. I'm reaching for an extra handful of that. And so the broader point is that if you're cutting calories with keto or without keto, you're probably going to lose some weight.

But there are corners of the internet where people don't talk about their brains or the size of their tummies. They are more interested in brawn. And when you go on the ketogenic diet, it actually can change your muscles because it makes them better at running on fat. So people have wondered, will these revamped muscles make them better at sports? Will it let them run faster, be stronger, more powerful? For Louise, knowing if the ketogenic diet can do this is her bread and butter. Because Right now, she's working with some of the best athletes in the world, a real group of stars. You know them, I know them. Champion Race Walkers. It's a weird sport It's weird though, isn't it? I mean, away from your study, it's a weird sport. I thought it was weird until I started working with Racewalkers because it's like trying to have a competition to see who can whisper the loudest. Yes. Jokes aside, Elite racewalkers are a thing. It's an endurance sport. To find out if keto could give these athletes an extra edge, Louise got more than 20 elite racewalkers, and for several weeks, she put them on a strict ketogenic diet while others got to eat carbs.

And so did they crush their opponents? Ketogenic diet turned out to be a disaster for the performance of these athletes. One of the things they said was, Look, it's the closest thing to death you'll ever get without being dead. What? What's going on? Why are they performing so badly? Here's what Louise found. When you're exercising, your muscles Girls use lots of oxygen, and burning fat uses up more oxygen than burning carbs. So ultimately, the carb athletes had an advantage. Basically, they had more oxygen in their tank. It's only about a 5% difference, but a 5% difference is really important for an athlete who's working at their limits. And in elite sport, I imagine that 5% could be the difference between gold and silver. It is. Yes, it is. It's a huge difference. We're seeing similar stuff in other studies, too. Louise repeated her race walker study and found exactly the same thing. The athletes were slower on keto. The research has looked into other sports like CrossFit, cycling, Gymnastics. For the most part, people don't do any better performance-wise when they're going keto. This year, Louise actually co-authored a paper with the title, Ketogenic diets are not beneficial for athletic performance.

Louise, who's a marathon runner herself, isn't tossing her pasta in the bin. Look, I've tried it for a couple of days, but unfortunately, I'm an athlete who has very little patience for feeling bad, and so just seemed a lot of pain to go through, and I just didn't have the patience. Going keto isn't going to help you fulfill your lifelong dream of being a race walker. Still, though, lots of people swear by this diet, or at least are interested in giving it a shot. Our last question is, what are the risks here? Well, here's what we know. People on this diet are more likely to have constipation and kidney stones. There's also evidence that all the fat that you're eating can mess around with the fat in your blood, potentially upping your cholesterol. But from the few studies that have actually tracked people over a couple of years, we see that this diet doesn't to increase your risk of getting a heart attack. It's hard to know what to make of this. But then let's go back to Blive, because something very odd happened to her. Yeah. A couple of months in, I realized that I was not getting my period.

I noticed it in particular because I was trying to have a kid. I was like, Oh, Okay. This is weird. Once, Blythe went off the diet. My period came back. Very suspicious. I think we found the cover of Blyth. But seriously, though, Could going keto really mess with your period? The only thing that we could really find in the research on this was a study on 45 kids who were between 12 and 19. They were put on this diet, and nine of them reported menstrual issues, including not getting their period. Now, experts told us that if you lose a lot of weight on this diet or any diet, that could affect your period. But that didn't really make sense for Blyve because she didn't lose that much weight. There was this one interesting clue in the literature, though, that maybe could explain what's going on here. You can see that researchers are using the diet to help people with this condition called PCOS or polycystic ovary syndrome. It's a hormonal condition that's linked to irregular periods. Studies have found that it actually can help some patients. At Science First, we just started thinking that perhaps if this diet has the potential to adjust your hormones in a good way, in a way that could potentially help with that condition, maybe it could also affect them in a bad way, like it did for Blythe.

We're really not sure. But if what happened to Blythe was a bit frustrating, what happened to her husband, Jack, was even more bizarre. Jack went on this keto diet, thanks to Science Versus, and he stayed on it for about six months. But then on a trip to Italy, all that pizza and pasta, he decided to quit. And this is where things were really weird for him. When he went back on carbs, he started getting hives on his skin. Like, itchy wells. When he ate carbs. When he ate carbs. They were so itchy. He was waking up in the middle of the night and getting into the bath and filling it with oatmeal to soothe his skin. Your entire body is just like this one big rash. It was horrible. Yeah, so he was doing fine on the ketogenic diet. It was only once he started eating carbs that his body went bananas. He talked to a bunch of doctors, went to an allergist, and was ultimately diagnosed with a gluten sensitivity, one that he never had before, or at least he didn't know about. He didn't have any symptoms. Blyve asked doctors and researchers what might have happened, and the best thing they could tell her?

Maybe going on this keto diet and almost completely cutting out all these carbs where your body gets to this place where it's not used to have them, not used to having them, not used to having them, and then reintroducing them, your body is like, mount this insane inflammatory reaction. Yeah, because that's what when we emailed Dom, asked him about this, he said, Elimination diets, like the ketogenic diet, can cause food reactions if they are quickly reintroduced. Yeah, it sounds like this is the thing that maybe can happen. Is it still a problem? Yeah. I mean, it's years later. He doesn't have bread. Wow, we really him over, didn't we? Oh, my God. And This is why we shouldn't self-experiment. I'm just kidding. Your mom was right. Mama's all right once more. When it comes to the ketogenic diet, where does this leave us? Well, what's really interesting about this diet is that it actually can change how your brain and body works. Your body starts to use ketones as a fuel source, right? Which could be really cool if you have epilepsy, maybe even if you have schizophrenia. Surely there's lots of people online who say that this diet makes them feel great.

But the fact that this diet is changing how your body is working, does open the door to the fact that it could change it for the worse. I mean, it's funny because for me, I'm like, these are foods I was eating anyway, right? Like, oh, I'm just eating less of one thing and eating more of a different thing, like more avocado, more bacon and almond or whatever. But it's so interesting how big an effect that can have. And these different systems of our body that that can actually fear with. And I guess I feel like no part of me was like, Oh, I guess I should be a little careful. It just did not occur to me. Yeah. So I guess I would just tell people to be careful. Yeah. I don't want to leave on an after-school special note, but it is maybe be a little careful. Yeah. Oh, thanks, Blive. Thank you, Wendy. Thank you for letting me tell my keto story. That's Science Versus The Ketogenic Diet. Hey, Michelle Deng, producer at Science Versus. Hi, Wendy. How many citations are in this week's episode? There are 92 citations in this keto episode.

If people want to see them, where should they go? Check out the transcript and our show notes. If people go on our Instagram, which is science_vs, what will they see this week? We'll be posting some facts from our episode and leave us a comment about what you thought about the episode. Yeah. If you've tried the keto diet, how have you felt? Did it supercharge your brain? Any weird symptoms? We want to know. Let us know. Yeah. You can also tell me on my TikTok which is at wendysuckerman. Thanks, Michelle. Thanks, Wendy. Bye. Bye. This episode was produced by Kaitlyn Sauri and Michelle Dang, with help from me, Wendy Zuckerman, Rose Wrimla, Shruti Ravindran, Meryl Horne, Aketi Foster-Kees, and Ramilla Karnic. We're edited by Blythe Tarrell. Additional help from Eric Mennel and Simone Palanen. Fact checking by Michelle Harris and Eva Dascher. Research help by Doria Risa. Mix and Sound Design by Emma Munga and Sam Baer. Music written by Bobby Lord, Bumi Hidaka, Peter Leonard, and So Wily. Recording help from Marissa Shia and Mary Sheddon. An extra thanks to all of the researchers that we spoke to for this episode, including Professor Russell Swerdlow, Professor John Ramsey, Professor Judith Wiley-Rosset, Professor Claire Collins, and Dr. Diedry K.

Tobias. Also, thanks to Frank Lopes and Joanna Lauda. An extra special thanks to Joseph LaBelle Wilson, Jack Weinstein and Mama Zook. Science Versus is a Spotify Studio's original. Listen to us for free on Spotify or wherever you get your podcasts. If you like what you're hearing, please rate and review us. Give us a five-star review. We tell people that a lot of the stuff they believe in is garbage, and people don't like that. But if you like it, then give us a five-star review. I'm Wendy Zuckerman. Back to you next time.