Science Vs - Weight Cycling: Is 'Yo-Yo Dieting' Dangerous?

Episode Date: August 6, 2026

If you have ever tried to lose weight only to find the weight crept back on, you’re not alone. In fact, for tons of people, this happens over and over again. This is called “weight cycling,” and a bunch of influencers are saying that this is terrible for us. They say that it can ruin your metabolism forever and that it can lead to stuff like diabetes and scary muscle loss. So could that be true?? And why does this happen at all? We find out with nutritionist Prof. Faidon Magkos, immunologist Prof. Alyssa Hasty, and health policy researcher Dr. Jamie Hartmann-Boyce.  Note: In this episode we discuss weight and weight loss. Please take care when listening, and here are some resources: National Association of Anorexia Nervosa and Associated Disorders (ANAD) helpline: 1(888)-375-7767 Crisis support: United States: US National Suicide Prevention Lifeline Dial 988 (Online chat available); https://www.crisistextline.org/text-us/ Text “HOME” to 741741 Australia: Lifeline 13 11 14 (Online chat available) Canada: Call or text 988 United Kingdom: Samaritans 116 123 (UK and ROI) Full list of international hotlines here  Other help available: spotify.com/resources Find our transcript here: https://tinyurl.com/ScienceVsWeightCycling  In this episode, we cover: (00:00) What we’re hearing about weight cycling (07:14) Why is it so hard to keep the weight off? (12:45) Does weight cycling break your metabolism? (18:58) Will you gain fat and lose muscle? (23:17) Weight cycling and inflammation? (28:35) Will weight cycling make you sick? This episode was produced by Rose Rimler, with help from Ekedi Fausther-Keeys, Meryl Horn, and Michelle Dang. Wendy Zukerman is our executive producer. We’re edited by Blythe Terrell. Fact checking by Diane Kelly. Mix and sound design by Bobby Lord. Music written by Bobby Lord, Bumi Hidaka, So Wylie, Emma Munger and Peter Leonard. Thanks so much to all the experts we spoke with for this episode, including Dr. Heidi Silver and Dr. Andrea Rossi. Special thanks to Jennifer C. Wolfe and Sasha Borissenko. And big big thanks to all the folks who called in to tell us about their weight cycling experiences.  Science Vs is a Spotify Studios Original. Listen for free on Spotify or wherever you get your podcasts. Follow us and tap the bell for episode notifications. Follow Wendy on TikTok @wendyzuk Science Vs on Youtube @ScienceVsPodcast Science Vs on Instagram @science_vs Learn more about your ad choices. Visit podcastchoices.com/adchoices

Wow, wow, wow, wow. So it's weird, it is true. It is true that weight cycling can mess up your metabolism. Not so fast. Hi, I'm Wendy Zuckerman, and this is Science Verses. Today on the show, why is it so hard to lose weight and keep it off? Plus, what happens to your body when you lose a bunch of weight and put it back on and lose a bunch of weight and put it back on? Because the internet is saying that this is.

This cycle, which is very common, is actually really, really bad for your health. But is it true? And just quickly, before we get started, I do want to say that if this is a sensitive topic for you, please take care while you're listening to the show, and we're going to put some resources in our show notes. Okay, to get into the science here, we have senior producer Rose Rimler. Hello, Rose. Hi, Wendy. Where do we begin?

The first thing I want to do is I want to introduce you to someone I recently talked about this, Quite a bit. His name is John Rossi. He's a musician. He's actually a drummer. I called him up because he is someone who has struggled a lot with his weight. I have been weight cycling most of my adult life, and it's not fun. Weight cycling.

So this is the term for when folks lose a bunch of weight, put it back on, lose a bunch of weight, put it back on, right? This is the new internet term that I guess in the 90s we were calling yo-yo dieting. Yeah, I think so. I think eight cycling is like a little bit more, sounds a little more scientific or something. And so John's story is that he initially lost a lot of weight in his 20s. That was like the first time he ever lost weight. He lost quite a bit of weight. And his appearance really changed. People, he said, were complimenting him a lot. He was getting a lot of positive attention. And it changed a lot of things for him. He said it changed the way that he dressed. So he said that before this happened, he was wearing like dark t-shirts and baggy jeans. And now I was wearing the most like funky pink cool stuff and skinny jeans. And I was I was in it to win it. What was your wackiest outfit from that time? I had, so I had a pink t-shirt that I like to wear with a pink like flannel overshirt,

like a button down over it, unbuttoned, with matching pink sunglasses. That's not pretty rad. It was, it was so bright. And it was so good, and I miss it. He eventually gained back a lot of the weight that he had lost, and so he put his pink outfit in the basement. So that was the first time, but he's since then gone through a bunch of these cycles, losing weight, gaining back weight, losing weight, getting back weight.

And he's not alone. Studies find that up to half of adults in the U.S. have gone through at least one weight cycle. Half of all adults in the U.S. have experienced this. Yeah, it's very common, and it's also very common for it to happen repeatedly. So another survey found that of people who do weight cycle, they go through on average eight cycles by the time they're middle-aged. And, you know, he's right on track for that average. I am currently on my ninth time trying to lose weight.

Wow. And how many-counting that first one? How many pounds do you think that is over the course of your life? I mean, if I had lost all of this together, I'd be in the negatives. Yeah, you'd like lost your entire self. Yeah, yeah, yeah. Like, I have lost multiple people, you know, over this time period. In fact, he says he's lost and put on hundreds of pounds over the last couple of decades. Mm-hmm. Yeah.

You know, John has worked so hard so many times that when this happens, it just feels awful for him. Terrible. Like, truly, like, I was failing myself. And I was, I was, you know, I had succeeded at something and then failed at it, which I think is probably. worse than just never succeeding at something. And it's really hard. It is, I would take every other challenge in my life and double them if I could get rid of this one. Yeah, and I heard similar things from other people who I spoke to for this episode.

Listeners called in and just seemed like there is a really common theme of frustration, sadness, and then also a lot of self-blame. Ugh, you know, I've done it again. I just couldn't help myself, or I wasn't paying attention, or I wasn't doing what I was supposed to be doing. I don't know how to get out of this cycle. When I was with a bunch of friends and had to climb on a scale in front of a bunch of people to be weighed to see if I could ride a ride at a carnival,

and my weight was right back up to where it had been over where it had. had been before I started Weight Watchers, three years before, I was devastated and went into a depression spiral that lasted for years. So people really want to know more about why this happens to them. And in this episode, we are going to get into that. Yeah. But we're going to get into more because beyond sucking, which it clearly does. Yeah.

Now there's a lot of internet claims that say that this is actually bad for your health. Cue the influences, Rose. Yo-yo dieting is so bad for us. Not enough people are talking about how damaging, repeated weight loss and regain can be. It wreaks havoc on our body's internal processes and the infrastructure that keeps us alive. Yo-yo dieting is killing you. And specifically what people talk about is that you're like ruining your metabolism. that you're going to end up with higher body fat percentage and less muscle than you would have otherwise,

and that you're just going to be sick. You're going to get diseases like tattoo diabetes, heart disease, that kind of thing. And you would have been better off if you just never tried at all. Kind of is the implication. Yeah, some people say that. So we're going to get into all of that. We're going to do that for John too. John is a very sciencey person, but he says this one, this is kind of hard for him to dig into.

This one's too close to home. I've read so many things. I've heard so many things. I just want to hear from people that I trust, like a true scientific look at all of this. Because I can't. I can't at this point. I really felt like, do-da-da-da-da-to-do. Rose.

You're a voice we trust. Oh, I have my cape. It's my cape, actually. Yeah, yeah, yeah, yeah. I'm just in costume. I'll be the voice. Yes. The science on weight cycling and is it really killing you coming up after the break.

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this excited about studying. Oh, man. Shop back to school at IKEA. Welcome back. Let's find out why it's so hard to lose weight and then keep it off. Because everything's political these days, it actually almost feels like the woke thing to say is it's so hard to lose weight and keep it off. And the people who say it like it is, they'll tell you, if you don't, and keep that diet, you can lose weight.

You know, so is this just wokeness and unwokeness gone mad or give me some actual data here? I mean, if it were that easy, we wouldn't have things like the National Weight Control Registry, which is set up to specifically find people who can lose a lot of weight and keep it off and track them and study them. That's how rare it is to lose a significant amount of weight and keep it off for longer than like a year. Right. And one person I spoke with, Elena, she's an actor from New York, she had heard about this registry. That was like my goal was like, I want to be in the registry. So I guess like, you know, if people do lose a bunch of weight and keep it off long term, Is there anything?

What's special about them? What special about them? Are they addicted to exercise and psychotic about what they eat? And that's the only way you can do it? Great question, Elena. What's happening? Is that what's special about them? Well, the scientists behind the registry have shared some things that these people seem to have in common.

Some of them are kind of random, like they tend to eat breakfast. Oh. So take with that what you will? Okay. They also exercise a lot, on average, an hour a day, these folks. An hour a day? Yeah, that's committed. Yeah, and to Elena's point, like, are they, I think she said psychotic about what they eat? I don't know if they're psychotic about it, but they're very careful. The researchers said that they exhibit, quote, a high level of dietary restraint.

Mm-hmm. So it really becomes their whole life? It has to become very important, yeah. Okay, so then why is it... Why does it take so much? Why does it take so much? That's right. Yeah. So there's a few reasons.

One is that when you lose weight, your hormones change. Your hunger hormones increase and your fullness hormones decrease. So if you, to this point of if you just stayed eating a certain number of calories that allowed you to lose weight in the first place, if you just stayed on that diet forever, you could keep this weight down. staying on that diet forever becomes harder and harder. Yes, it becomes harder and harder because your body is nudging you towards eating more to counteract that weight loss. And there's a really cool study I want to tell you about that shows this and shows just how like below conscious awareness this is happening.

So in this study, researchers gave people a drug that pulls sugar out of your body and into your urine. So you end up peeing out a lot of sugar. This is in the diabetes world, this drug. Okay. Because you're peeing out a lot of sugar, you lose weight. You're like excreting calories. So people on this drug tend to lose weight.

If you tasted your urine, it would be sweet? Yes. Okay. You know, if you run out of honey, you know? It's good to have a little backup. This was a controlled study. They also had people take a placebo pill. They had another group on a placebo pill.

So if you were in this study, didn't know if you were given a pill that was causing you to excrete more calories or not. Okay. Uh-huh. Then they followed people to see kind of like how they ate after that. And they found that the people on the drug, without knowing that they were losing weight, started to eat more. The people on the placebo drug know that there wasn't that kind of change. Mm.

Right. So just like those hunger hormones kicking in, they were just a little bit more hungry. just a little bit, yeah, but it adds up. So this is one reason why it's so hard. Your body wants to conserve calories, which for most of human history, we were hunting for food. Food was hard to get,

and that's how humans evolved, and now it's very different. So it does make perfect sense that there are these things beyond our control in our body that are pushing us towards weight gain rather than weight loss. And I think this is why it's so confusing and frustrating for people because they're still eating below what they want to eat. They're still

like restricting their dietary intake. I heard someone give a talk where they said keeping off weight is like holding a rubber band really tight. So you have to keep holding it. And it's very hard to do that. Eventually relax a little bit. And another thing that people bring up is about metabolism. This idea that your metabolism changes from weight loss. And that's a lot. And that's another factor. That's right, because people, the people who say that weight cycling is dangerous wasn't, one of their arguments was that it actually breaks your metabolism in the end, right? Right. Therefore, making it even more difficult to lose weight. Yeah, so let's, so let's dive into metabolism. Yeah. I talked about this with Favin Madco's. He's a professor in the nutrition and

exercise department at the University of Copenhagen. And the first thing he told me was that, yes, your metabolism will get slower when you lose weight. When people lose weight, they burn fewer calories. And this happens both at rest and during exercise. And that is completely normal because a smaller body actually needs fewer calories to sustain its function. So it is true. It is true.

As you get smaller, your metabolism does slow down. Yes. So basically what our metabolism is mostly doing is running a complicated machine. the size of that machine matters. If you're a bigger machine, you need more energy, you need more calories. If you're a smaller machine, fewer calories, less energy.

And so as people lose weight, they have a smaller machine to run, and they need fewer calories. And that in itself could be challenging to sort of dial down your calories more and more. All right. So then can we take it one step further? Because the internet always does.

Yeah. If you then weight cycle, does over time that process break that machine avows and ultimately break your metabolism in some way. So the people who talk about this, they often talk about this one particular study. Let's talk about the biggest loser study. The biggest loser study? The biggest loser study?

The biggest loser. Remember that, Wendy? The reality show? Yep, the reality weight loss competition. Uh-huh. Yes, of course I remember it. Yelling, lots of yelling at people. Lots of yelling.

Dan, no! Yes! You can. Get back to work. Come on. Dina, come back, Dina. You're acting pathetic. It was really intense.

It had people do hours of exercise a day, like two or three hours a day while they were cutting calories as well significantly. It was mad. It was mad when you think about that moment in history. And then everyone would go for the weight where they would measure themselves and everyone would line up. The public weigh in. The public weigh in. It's just so medieval. And it was just, wow.

Wow. Wow. Okay. We were doing that. Why are we talking about it on science versus? Because one good thing, interesting thing, came out of that show. Science. We have some science from that show. Because one season, scientists actually followed contestants before and after they were on the show measuring their resting metabolic rate. So they did that before they started the show, before they lost weight. And then after the show, when they had lost weight. And they lost a lot of weight. On average, this group of people. It was like 16 people. They lost about a third of their body weight on average. Wow. And so did their metabolism slow down as expected? So it slowed down, of course, because they're smaller.

Machines were smaller. But then the question is when they put the weight back on, did they? What happened next? They did. So over the course of six years, they, most people put some of the weight back on or all of it back on. And the scientists circled back. They got back to them after these six years, and they measured their resting metabolism again. And so you would expect if the weight had come back, then the metabolism would bump up as well. Right? That's right. So what happened?

They didn't find that. These folks, their metabolism, on average, was still suppressed years later. By how much? Well, here's Fathin. So the resting metabolic rate was lower than predicted by about 500 calories per day. What is that in food? It's a Big Mac. Okay.

Wow, a Big Mac a day. That's how much their metabolism had dropped on average. Right, meaning like, it was next to someone who hadn't had this experience but was sort of the same size. Yeah. That other person could eat a whole extra meal, essentially. Yeah. per day than they could to stay the same week. So it's weird. It is true. It is true that weight cycling can mess up your metabolism. Not so fast. Okay. This is a weird study. It's small. What people did

is quite extreme. We have other studies that are a little bit more in keeping with the reality of what happens to most people. And bigger, more people in the studies. Great. Yes. This was just 16 people, right? Okay. So what else? other studies show. Some studies do also find some, some effects, some like suppression of the metabolism. It's not just the biggest loser. Okay, right. But the biggest loser found the biggest, most of the studies find something much smaller. And in fact, a meta-analysis found it was, it was quite a small amount on average. The metabolism lowered by a small amount on average. Yeah. And it's actually so small that Fayden argues that it actually could be within the,

the margin of error for what these measurements can actually detect. Uh-huh. So this is good news for John, who's been weight cycling nine times, right? It suggests he hasn't broken his metabolism, right? Yeah, yeah. And I called him actually, and after we talked the first time, after I done some research, I called him back, and I told him about some of the science here, including this metabolism finding.

I've been told by so many people my whole life that, I, you know, that I am hurting myself and I am causing myself these, like, long-term issues. From the weight going up and down? Yeah, yeah, yeah, to the point where it has scared me to try losing weight sometimes. And I'm like, no, what if I'm doing more damage? And so that's really encouraging. Science to the rescue. No, we're such nervous.

I know. It's nice, because science doesn't always come to your rescue, you know. It does not, and sometimes it really kicks your ass. Okay, so the next thing I want us to look into is what happens to your muscles when you lose weight and then put it back on and lose weight and put it back on? Because the way some people talk about it online, it's almost as if your muscles will disintegrate over time. Do you know what I mean? This whole internet's so extreme.

What is happening to your muscles? It's extreme. What people do say is that, you know, when you lose weight, you lose some of your muscle, and then when you gain it back, you don't get the back the muscle, or not as much. You get back more fat. Okay. Yeah, yeah, yeah. And that can happen.

Uh-huh. So there is a study in North Carolina where researchers followed people who went through a weight cycle over about a year, lost weight, gained it back. They found that people lost 74% of the weight as fat, but when they gained weight back, 88% came back. That's fat. Right. But it's not a huge difference, but it's definitely there, right? It's there. And you could imagine if you have that difference over time with weight cycling,

you're going through this nine times, the fear would be that then it would compound. And you would, with every weight cycle, lose more and more muscle. Is that what we see? Well, not every study finds this. So a very similar study from... Oh, Rose, you've done it to me again. Look, you got to read more than one study. And you got to tell me.

Then you get this. All right. So what's the, you guess? Okay. Don't tarry me. Let me tell you about this other study. Yeah, tell me about this other study. Great.

This one was from Germany. Okay. Researchers similarly followed people when they lost weight and gained it back. Uh-huh. And they gained pretty much the same amount of fat as they had initially lost. Same amount of muscle. No real difference. So what you might ask me is the difference between those two studies?

Yes. That is what? You might ask me. I will ask you, what is the difference between those two studies? The difference was age. So in the study where people gained back more fat than they had lost, they were older. They were people in their 50s, 60s, and 70s. Well, in the study where people did not really see a difference,

they gained back just as much muscles they had lost, they were younger, 20s, 30s, and 40s. And we know that over time, you lose muscle. We all lose muscle whether we're going through weight cycling or not. That is just one of the ingloriousness. It just happens to everybody. Of aging. Yes. So this isn't such a big deal, then, you think?

I mean, it's, it's, that's, this is a tough one because, and I have spoken to some researchers who are genuinely worried about this. So that's a legitimate concern, but the way people talk about this online that you're like, doomed to ruin your body composition. I didn't see any evidence that that's the case. Right. But yeah, I mean, and then your question, Wendy, does this compound, like, does with each successive weight cycle, you lose more muscle, you gain more fat?

Yes. I can't really answer that because we don't really have those studies. We have very few studies that follow people for more than one weight cycle. And that's true for all this. Mostly it's just one round of weight cycling. What did John think about this? You know, John said he wasn't, this wasn't something he was actually that worried about. Because from his own experience, he was like, no, I, when I lose in gain weight, it doesn't really affect, it doesn't seem to affect the way I can operate my body.

Like, he talked about being a drummer. I trust my arms, whatever size I am. Like, I trust that my muscles will do the same thing. Yeah. So that does make sense. I wasn't too worried about that, but I mean, it's nice. Yeah. Like, I wasn't worried about it, but cool, I'll take it.

All right, Rose, after the break. We're going to talk about, like, health more broadly. Inflammation, diabetes, heart disease, does weight cycling make all of that worse. Come in? This episode is brought to you by Accenture. When your advertising operations fall out of sync, everything else follows. Spotify and Accenture are working together to reinvent the rhythm of ad sales, using automation, analytics, and smarter workflows to simplify campaign delivery

and access better data across the business. business. The result? Less time spent on operations, more time connecting brands with the moments and fandoms that matter most. Learn more at Accenture.com slash Spotify. Right now for a limited time, everyone's part of the Buick team, even you. Buick's employee pricing for you event is on now. Get a purchase credit of up to $3,168 on a 2026 Buick Envision. Surround yourself with signature Buick refinement from an available massaging driver's seat to an expansive panoramic moonroof and a stunning ultra-wide 30-inch diagonal screen. Don't miss Buick's employee pricing for you event. Visit buick.com for more details. Welcome back today on the show. We're talking about weight cycling or yo-yo dieting.

What happens to your body when you lose a bunch of weight and put it back on? Lose a bunch of weight and put it back on. The internet says that this can over time make you sicker and sicker, and we're looking into that claim. And one idea that I really want to probe is around inflammation and that this weight cycling can ultimately increase the amount of inflammation in your body. Tell me the science, Rose. This comes from what we know about fat tissue on our bodies. So, you know, you and I, Wendy, and maybe our audience probably assumes that fat, the fat on our bodies is inert. It's just like squishy stuff that's there to act as padding or maybe, you know, provide a little extra energy if we need it. And actually that's what scientists used to think, too, until like the mid-90s.

When they started to realize that fat is actually a very active tissue in the body. And one of the ways it's active is that it's actually full of immune cells. I spoke about this with Alyssa Hastie. She is currently a professor at the University of Texas Southwestern Medical Center. Every single immune cell that's known to immunologists exists in our fat. This is especially true for the fat that collects around our organs, visceral fat, which you're probably familiar with. The more dangerous fat, that's the fat scientists are worried about. Yeah, when fat collects around your organs, that's bad.

And one reason is because that's not really a place where we're, meant to store fat. It's like not set up. The body isn't really set up to support the fat there. And so there isn't really like good blood supply for those cells, those fat cells in that area. And so they get like stressed out. They don't get enough oxygen and they like malfunction and they even die. So then there are these white blood cells called macrophages that have to go in and clean up the debris from those dead and dying cells. But then they can get overwhelmed. So here's Alyssa. And so they send out signals that say, hey, other immune cells, other macrophages, come help us out here. We've got to take care of this debris, this dead cell. So then you get more, basically more and more inflammatory cells, right? More and more macrophages then calling out more and more immune cells to come and help. And you just get this kind of vicious cycle. But then the question for us today is, does that get worse if you,

lose weight and put it back. Right. So that's what Alyssa wanted to test. So she set up this mouse model where she had the mice gain weight by feeding them a high-fat diet for nine weeks. Then she switched them to a low-fat diet. Was that kind of, is that like putting the mice on a crash diet? Yeah, it definitely is. And then she yelled at them like in the biggest louisa. Yeah, and she made them go round and round and around in their little hamster.

Yes. For hours and hours. Run, run. And televised it. Yeah. So then to have them go through like a whole cycle, she had the mice, she put them back on a high fat diet for another nine weeks. They gained weight again.

Uh-huh. Checked on their immune cells. And what she found, especially regarding this type of immune cell called the T-cell, was surprising. The T-cells were elevated even further in the weight cycled compared to the obese only, despite the fact that they were the exact. same weight and had the exact same visceral fat mass and total body adiposity. So these were even more like agitated. The mice were worse off in terms of what their

T cells were doing than the control mice who had never weight cycled but had been obese basically the whole time. The immune cells didn't like it. They're going back the cycling. Uh-huh. And so this is how Alyssa puts it. The body remembers. The immune system remembers our body weight and gains and losses in that. Uh-huh. The body remembers.

What's going on there? We don't totally understand all this. But it seems like something about this, like, the stress, the weight loss, the weight gain, the weight loss, is like turning on the immune system in a way that's hard. to turn off. And that could be leading to some kind of chronic inflammation, which we know is bad for us in all kinds of ways. We said science isn't always your friend. No. Do we know why this is happening? And obviously this was just a study in mice. You're going to now give me another study where they found something totally different? Well, I mean, wait, are you really going to give me another study that found something different? Right.

rise. Yes and no. Okay. So after looking at this study in mice, I wanted to look at studies in people. Thank you. And I did find, along these same lines, I did find studies that compare people who have weight cycled versus people who have not weight cycled, but they both started out of kind of the same way.

Yes, yes, yes. And what those studies often find is that the weight cyclers have worse health outcomes than those who haven't weight cycled. In what way? These studies have found a higher risk of heart failure and higher risk of death, actually. A couple studies. Wow.

So I don't want to leave things there, though. And the reason is, you know, those studies are not bad studies, but they can't answer some basic questions here. So, like, they're just observing what happens between one group and another. You can't say, like, weight cycling cause people to die or to get heart failure.

Got it. Got it. Got it. We need a different kind of study for that. Sometimes we don't have control trials. Anything else? Yes. Yeah, but in this case we do.

We have some randomized control trials that could help us. Uh-huh. Tell me about it. So I talked about this with Jamie Hartman-Boyce. She is an associate professor of health policy and management at the University of Massachusetts Amherst. And she wrote a review paper looking at studies where people lost and then regained weight after going through what are called supervised weight loss programs. Mm-hmm. eating a bit less, you're at a calorie deficit, and you're exercising more.

So we're not looking at people who are like on a juice cleanse for six weeks. We're looking at people who are like eating more vegetables and moving their bodies more. So Jamie's question was, how does the health of these people who have lost weight in this healthy way gained much of it back? How does it compare to people who have never lost weight, who are the control groups? Yeah, great. And one of the things we found is that even if you regained the weight back, right? So even if you started a certain weight, you did your diet and exercise program, you stopped it, you went back to your starting weight. Compared to someone who had stayed at a stable weight the whole time and not done that program, you were still less likely to get type 2 diabetes.

And it wasn't just diabetes. It was also lower cholesterol and lower blood pressure. Why was weight cycling healthy in this case? it seems like it could come down to how people lost the weight. Making healthy changes, getting a little more exercise, eating more vegetables, even if people aren't able to keep up those new habits forever, the period of time where they were doing those healthy habits, which resulted in weight loss, that's what was good for them. But these other studies, we don't know how or why they lost the weight.

And then with the mice, you know, it was like a crash diet. This was like healthy changes resulting in weight loss. So is it even about the weight loss at all? Or it's just that for a portion of the study, these people were eating lots of vegetables, moving their bodies, and that's what was good for them, whether or not they lost weight or not. That's one. Yeah, I think that's a fair interpretation.

I mean, there's a lot of nuance here, but it does make sense if you think about, if you know the broader literature about weight and health. So there's a study I love. they it's a big survey like 12,000 people are in it they asked about healthy habits so like how much fruit and veg do you eat

do you exercise regularly smoking drinking and these are people of all kinds of weights yes all kinds of weights and they tracked them over time and what they were measuring was all cause mortality so like that's the big one like are you more likely to die they found that the thing that mattered the most

for you know death was not your weight but the healthy habits that you did. So if you were someone who your BMI technically puts you as obese, but you have all these healthy habits, you were just as likely to not die as a person whose BMI was normal and did those healthy habits. What these studies are suggesting is if you're doing healthy things, that's the key.

Yes, and you have a lot more control over that than you have of your body size. So it makes more sense to focus on that. And that's what Jamie said as well. So I think the data is very clear that if like what we're trying to do is improve our health and well-being, right? Then, you know, if we eat healthier, we exercise more, regardless of what happens to our weight. And one of those things that can happen is that we lose weight and regain it, we are doing something good for ourselves. Okay? And for the people who love us who want us to stick around for longer.

So when I told John that it's the healthy behavior, more than the weight that really matters. This is what he said. Wow. That's really cool. That's great. Science, back to being your friend. But it was also, there's something I think about it that was slightly annoying to John

because it made him think of all the bullshit he's had to sort through and all the people saying, like, oh, if your weight fluctuates a lot, you're going to really harm your help. Those beliefs have been so common and so repeated over and over and over again, that it shows me that, you know, people don't know what they're talking about with

this stuff all the time. And it's another nice reminder to not let other people shape me in a literal sense in this case. And then I should, I should worry more about, you know, what I think and what the science says than what people tell you, you know. So what does this mean for that fabulous pink outfit that John's got? I did ask. Did you? Yeah. You said your confident, wacky outfit was like, I think you said it was like, was it hot pink?

Yeah. Oh my gosh. So much hot pink. And skinny jeans? Yep. Reflecting on that, it strikes me as a very early 2000s outfit. So what would the, let's say you get that burst of confidence and creativity and you want to express yourself through wacky dress? What does the 2026 version of that look like?

Well, 100% goofy animal shirts, always. I love animals so much now. And probably still skinny jeans because I don't care if they're in style or not. My boat looked great in those jeans. That's science verses. Thanks, Rose. How many citations are in this week's episode? This week there are 66.

66. And if people want to see them in all their glory, where can they go? Check out the transcript to find that link to the transcript in our show notes. Thanks, Rose. Thanks, Wendy. This episode was produced by Rose Rimler with help from McKeddy Foster Keys, Merrill Horn, and Michelle Dang. Wendy Zuckerman, that's me, is our executive producer.

We're edited by Blythe Terrell, fact-checking by Diane Kelly, mix, sound design and video editing by Bobby Lord, music written by Bobby Lord, Boomi Hidaka, So Wiley, Emma Munga, and Peter Leonard. Thank you so much to all of the experts that we spoke to for this, including Dr Heidi Silver and Dr. Andrea Rossi. A special thanks to Jennifer C. Wolf and Sasha Borysenko. A big, big thanks to all of the folks who called in to tell us about their weight cycling experiences. Thank you so much.

It means so much to us that you trust us to tell us your stories. So thank you so much. Science Versus is a Spotify Studios original. So listen to us for free on Spotify. or wherever you get your podcasts. We're all over. We're on YouTube. We're on Apple.

If there's podcasts there, so are we? Like and subscribe, follow, do all that stuff. And get in touch with us. We're also on TikTok and Instagram. All the ways to get in touch are in the show notes. I'm Wendy Zuckerman. Back to you next time. Real Canadian Superstore has everything you need this back-to-school season.

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