Science Vs - Colon Cancer: Should Young People Worry?

Episode Date: March 19, 2026

Colorectal cancer has long been thought of as a disease of older folks. But that's changing — fast. Rates in older people are actually going down, and more and more people under 50 are getting this disease. And a surprising number of them are dying from it. So what’s going on here? We dig into why young people are getting hit harder. Plus, we often hear that you should watch out for changes in your poo. But what changes?? We’ll find out. We talk to gastrointestinal medical oncologist Dr. Michael Foote and cancer biologist Prof. Ludmil Alexandrov. Find our transcript here: https://tinyurl.com/ScienceVsColonCancer In this episode, we cover: (00:00) Becca’s story (05:52) What the rise looks like (09:06) Is there something different about this cancer? (14:13) What symptoms to look out for (17:41) Why is this happening? (21:34) The hunt for explanations This episode was produced by Michelle Dang, with help from Rose Rimler, Meryl Horn and Ekedi Fausther-Keeys. Wendy Zukerman is our executive producer. We’re edited by Blythe Terrell. Fact checking by Erica Akiko-Howard. Mix and sound design by Bobby Lord and Bumi Hidaka. Music written by Bobby Lord, Bumi Hidaka, So Wylie, Emma Munger and Peter Leonard. And thank you to Prof. Caitlin Murphy. 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. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hi, I'm Michelle Dang, and I'm filling in for Wendy Zuckerman this week. And to start off today's episode, I want you to meet Becca Lynch. Becca lives in Colorado with her dog. She's 30 years old now, but throughout her 20s, she was leading a pretty hectic life. Kind of have always been pretty, like, full steam ahead. I've never been, like, comfortable not being busy. She was getting her master's, growing her career, and being, super active. I go like climbing, I go to the gym. I was running a lot. I did a half marathon

in 2024. Playing live music. Yeah, I have a little duo with a friend of mine that we play around town sometimes. But a couple of years ago, when Becca was 28, she noticed a change in her body, specifically in one area, the poo department. She noticed she was going number two more often, like five to six times a day. And it wasn't that, there were a couple of weird things she saw in these frequent poos. And fair warning, we're about to get a bit detailed here. So for one thing, there was blood. It was like a dark, almost mucusy, kind of thicker, bloody substance that was everywhere, like when I was going to the bathroom. And it was every single time. And the other thing she noticed is that her poo

started to take on a different shape than usual. Like thinner size-wise, like pencil thin. I did the thing that everybody does. Like, I googled it. Obviously, I googled all my symptoms. The results spit out quite a list of things it could be. Ulcerative colitis, IBS, Crohn's disease. Becca thought she should get it checked out, but didn't go in right away.

And then one day, she was scrolling on social media. Someone's video came across my feed. I think it was on Instagram of someone talking about the exact same. symptoms. She had said, like, for years, she thought she just had hemorrhoids, right? But this woman didn't have hemorrhoids. She had something a lot scarier, colon cancer. It was really advanced, stage four, and she was making these videos to tell people what to watch out for. And this was the push that Becca needed. I think it definitely solidified, like, okay, I should go to the doctor. Her doctor ordered a colonoscopy, so Becca eventually went through

the prep where you have to drink this gross liquid and poo a whole lot. And then she went in. I went there first thing in the morning. They just took me back and I met the doctor who was going to be doing it. You know, he was very like chipper and just like, yeah, we're going to figure what's going on. He's like, could be a bunch of things. Like, it might just be hemorrhoids. Like, don't worry about it. You're going to be in and out of here in half an hour. Like, I'll see you in there. And then they rolled me back and that was it. I took a lovely nap. When Becca woke up, there was a nurse there, and immediately Becca could tell something wasn't good. The nurse told her she was going to go out to the waiting room to get Becca's friend who had come to pick her up.

And she was just like, we're bringing your friend back because the doctor has to tell you something. And I was like something bad. And she was like, yeah. And then she left. I waited there for 10 minutes. she left me with a bag of goldfish and a sprite. I sat there and waited. And eventually my friend came back and I was trying to keep it light. But at that point, I think I kind of knew. Like, I knew it wasn't going to be good, obviously. The doctor came back in. And I just remember,

like, it was more so his body language and, like, facial expressions that were more upsetting than, like, what he was saying because he had been this very, like, chipper, bubbly person before, like, the last time I'd see him. When he came back in, he was very sad. And he, like, sat at the foot of my bed. And he just was like, we found a mass. It's five centimeters about the size of a lemon. For Becca to officially get a diagnosis, the doctor told her she would need more scans and surgery. And he kind of ended it with being like, if it is cancer, which I'm certain that it is, you'll be the youngest person that I've ever seen with it. Becca was eventually diagnosed with stage three colon cancer at age 29. And this was really weird.

She didn't have any of the usual risk factors. They ran genetic tests and didn't find any explanation. It all felt very strange. I knew that it was happening, but it really felt like I was watching it happened to someone else. But from that moment on, time kind of split, and I just went into this kind of numb headspace of my right, well, we have to deal with this. So, you know, we're going to deal with it and we'll figure it out.

And Becca isn't the only person having to deal with this and figure it out. Around the world, more and more young adults are getting diagnosed with colorectal cancer. In the U.S., one in five people diagnosed with it are now younger than 55. That's a big increase from just a few decades ago when only one in 10 colorectal cancers were being diagnosed in younger people. And that's not the only concerning thing. We're hearing that young adults are more likely to get diagnosed with a cancer that has already progressed pretty far, despite being otherwise healthy. So today on the show, we're going to talk about what exactly is going on here.

Why are so many young people suddenly turning up with this type of cancer? And we'll hear more about what this has looked like for Becca. All that is coming up. I'm not an astronaut. I don't need an astronaut. Audiences have spoken. Project Hail Mary is an awe-inspiring masterpiece. So, I met an alien.

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988 suicide crisis helpline is funded by the government in Canada. Welcome back. I'm producer Michelle Dang. Today on the show, we're looking at colorectal cancer. And with me is senior producer Rose Rimler. Hey, Rose. Hi, Michelle. You know, Rose, I wanted to make this episode because I kept seeing scary headlines about it.

this about colorectal cancer increasing in young people. Have you been seeing these headlines, too? Yes, I have. I've been seeing headlines about people getting colorectal cancer really young, and there's been some really high-profile people that have gotten it and unfortunately actually died from it. So I'm thinking of the guy from Black Panther that was a little while ago. Yeah, Chadwick Bozeman. Yes. Yeah, he died from it in 2020, and he was only 43. Oh, that's awful. Yeah. And then just last month, the actor James Vanderbeek, he also died from colorectal cancer, and he was 48. Right. Yeah. And by the way, this term colorectal cancer, it includes both colon cancer and rectal cancer, and sometimes also called bowel cancer. Okay, got it. And for years, doctors had thought of these cancers as cancers that older people

get. In fact, Becca ran into this too. The hospital that I went to, they put me in this support group. It was like a Zoom support group for other people with GI cancers. And I joined it once. And it was like me and then four women all in their like 70s and 80s. And they were all so kind and so lovely. And they were very sweet to me. And like, I think one of them told me she was pissed off. at God on my behalf, which I thought was very sweet. And the thing is, like, these cancers are still more common in older people. If you are under 50, the risk of getting this cancer is actually very low, way less than 1%. But this increase is real and it's freaking doctors out. So it's not, because sometimes you hear about a disease going up and it turns out what's really happening

is that doctors are getting better at catching it or diagnosing it or something. But in this, case, it sounds like what you're saying, Michelle, is that no, it's actually going up in young people. It's simply going up. Okay. There's more cases and there's more deaths. Okay. And doctors really caught onto this in the 90s, but the risk keeps increasing with each generation. Like, take a 40-year-old who's part of the millennial generation.

My generation. Oh, your generation? Yep. And compare it to a 40-year-old who's part of the boomer generation. My generation spiritually. Really? No, just kidding. Yeah, so the 40-old millennial, compared to a 40-old boomer, the millennial has a two to three times greater risk of developing colorectal cancer. So if you're 40 now, basically, your risk of colon cancer or colorectal cancer is higher than someone who was 40, you know, in the 80s or 90s.

Yes, exactly. Geez. Wow. That's real. Yeah. Yeah. And in the U.S., coloractal cancer was just declared the leaving coffee. of cancer death in people under 50. It's led to nearly 4,000 deaths a year. Wow. So the thing I want to

talk about next is the fact that when young people are diagnosed with this cancer, a lot of the time it's really serious. You hear about people turning up with stage three or stage four cancer upon diagnosis, and studies have found that more than half of cases in early onset colorectal cancer are caught at these later stages. That sucks. Yeah, that's makes this cancer sound really scary because stage four, for example, is when the cancer has already started to spread to different organs and other parts of the body. And if this is the case, it can be incredibly hard to cure. Your chance of dying within five years with colerctal cancer at stage four is about 80%. Wow. Okay. So I wanted to find out like, why is this?

Yeah, what's going on here? So I called up Dr. Michael Foote. He's a gastrointestin. oncologist from Memorial Sloan Kettering Cancer Center. And he's been watching what's going on here. We've been worried about this for a while, you know, over 10, 15 years, but it has reached a critical point in the last few years. And I wanted to know, is there something weird or creepy about the colorectal cancer that young people are getting? Like, is it moving faster or is it more aggressive? And Michael told me, no. Based on the studies we have, it looks like... Once they're diagnosed, the tumor behaves pretty similarly to a dozen adults. It responds to treatments in the same way.

It can be just as aggressive. So why are young people showing up sicker? Michael says that young people's symptoms tend to be worse and the cancer spread further, not because of this idea that cancer is more aggressive, but because it's often getting caught a lot later than it is in older people. Not their fault, but they've had a longer amount of time before they were diagnosed to touch this. Well, that makes sense to me, Michelle, because they're not routinely getting screened because they're too young to start getting screened with colonoscopies. So if there was a really

young cancer, a really new cancer that wasn't causing any symptoms, there would be no way for them to know. But an older person who is getting screened, that would get picked up. Yeah, exactly. Like, the main reason that we find this cancer is with a colonoscopy. And we're just not usually giving those to young people unless something is wrong. And what is interesting is that in older people in the U.S., rates of this kind of cancer have actually been decreasing. Like, fewer people are getting it, fewer people are dying from it. And we think that's partly because we've gotten, like, pretty good at getting older people to go get colonoscopies regularly, where they can catch polyps in your gut that might turn into cancer. So the rates in older people are going down, but the rates in younger people are going up?

Yeah, it's just like dichotomy or discrepancy of like, why? Why is it going down for most of the people who are getting this? Right. But going up particularly for young people. And because of that, several years ago, doctors did decide to lower the recommended age for your first colonoscopy, for most people, from 50 to 45. There's actually people who say it should be even lower. Okay. Another piece of all of this is that for a lot of these young people, the symptoms can be easily confused for other things.

here's Michael Lilligan. I have a young person right now who's in their 30s, in their mid-30s, who has an extremely aggressive cancer type that is very, very sick with metastases all over his bones. So this patient of Michael's has stage four colon cancer. And what's weird is that Michael told me that their main symptom was back pain. Wow. Okay.

I mean, that could be anything. Like, who doesn't have back pain? I could imagine you wouldn't go and get seen for that, you know, certainly not by an oncologist. Who would think you'd have cancer just because your back hurts? Yeah, exactly. Here's Michael. Why are you having so much back pain? Why are you having this going on?

No one would ever think about colon cancer. And then we found it. You know, we found it on a colonoscopy, and he's been ongoing with treatment. How did that patient react when they heard the news? They were absolutely terrified. Yeah. And the real reason this patient had the back pain was because the cancer had spread to his spine. Are they still with us?

They are, yeah. And, you know, it's not great. They're treating the cancer, but it's aggressive. So basically, Michael and his team are just trying to make him feel better and give him as much time as they can. Less pain at least. Mm-hmm. Yeah. Now, Michael says that that back pain as the only symptom is extremely rare.

Yeah, we're really freaking everyone out, Michelle. with that one, that story. I'm sorry, yeah. But, you know, changes in your stool are much more common. Okay. Like blood in your stool and even abdominal pain. But even those symptoms are something that you could mistake for something else. Mm-hmm.

Okay, actually, Michelle, I have a question for you. I have seen, like, a lot of chatter about this online and people talking about, like, symptoms to watch out for. But mostly they just say, like, look for any change in your bowel movements. It's like, get that checked out. I find that really broad, like not very helpful. I've seen those kinds of videos too. And I'm curious, too, like, what exactly should you look for in your poop? Yeah.

And so I asked Michael for you. Thank you. He told us that you shouldn't panic over a few weird poo days. But it's more like if you see changes or feel pain that lasts for weeks, then get it checked out. This includes things like diarrhea, constipation, and dark tarry stools, or bloters. like what Becca saw. And Michael has some more particular advice here, too. What we typically say with the stool is the stool's become thinner, meaning, you know, if there's a tumor there, it starts to press on the colon and like a little, like a little cylinder,

squeezes the stool into thinner shape, right? Because if there's less space in the tunnel, you have a smaller diameter there for the stool to go through. So it starts to get thinner. And while Becca, she had a lemon-sized tumor in her colon. Right. And she was talking about the skinny stools as well. Mm-hmm. Like, the mass was putting a lot of pressure on my colon, which was obviously making me having to go to the bathroom a lot more often, and the mass was also what was bleeding, so that's where the blood was coming from.

That makes sense. But Becca's experience with her cancer speaks to another huge problem that doctors are seeing, because some of the stuff, like some of these poo symptoms, they often don't show up until the cancer is already pretty far along. When the tumor is already there and has had a chance to grow, and cause problems. Which is still so crazy to me, because when I think about, like, how long I was having symptoms, really, it was, like, noticeable symptoms were only a few months, and it was still stage three.

Thanks. And that, plus the fact that some of the symptoms can be vague, means that sometimes young people get misdiagnosed by doctors or even told they're too young to have colorectal cancer. So, you know, they don't get the tests that they need. Like, in a big survey, four in ten young people with colorectal cancer were initially told that they were too young to have it. Oh, wow. Okay. Overall, it can take a really long time for young people to get diagnosed.

And one study found that compared to older people, young people waited 40% longer to get a diagnosis from an oncologist. So by the time they get to us, it's further along in their disease course. So bottom line, it's not the disease itself that's doing something weird. It seems to be more like it's sneaking up on people and their doctors too. and getting found after it's had a lot of time to get dangerous. So I guess that answers the question of why is it more likely to be caught at a later stage in younger people, but it doesn't answer the question of why are younger people getting it at all in such increasing numbers?

Yes, that is the big question. And actually, we'll be looking at that next. Why is this all happening? Because I'm very impatient. I want to know now. Yes. So after the break, we'll take a look and talk to the scientists he's trying to find out. Okay, I can wait until after the break.

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Have it all with Bulu on Disney Plus. Welcome back. I'm Michelle Dang. We just learned that colorectal cancer is on the record. in young people. And the question now is why. So we're on the trail trying to figure it out. Like what the hell is going on here? And I'm here with senior producer Rose Romiller. Hello. Hey Rose. So yeah, one thing that comes up a lot is diet. People are eating a lot more ultra-processed food than they were before. And a big study just came out on this. It looked at this

big data set of almost 30,000 nurses and their health. I don't know if you're familiar, like the nurses. The nurse's health study? Yeah. Yeah, it's a group of nurses that have been followed for a long time and used in a bunch of studies. And what they found in this study is that people who ate the most ultra-processed food had a 45% higher chance of having polyps in their gut, which polyps can be harmless, but sometimes they do lead to cancer. Okay, so people who ate more ultra-processed food had more polyps. Very suspicious. not super surprising because, as we know from the ultra-processed foods episode, they tend to be associated with a lot of bad health outcomes. As we know from the fiber episode, if you're not

eating a lot of vegetables, you need the fiber and vegetables. So that all makes sense that that would be bad for your gut and probably create an environment that could be helpful for growing cancer. Yeah, it's like we always come to that conclusion in science versus episodes. We do. It's like, eat vegetables. Okay. Over and over and over and over. Yeah. And that is because we do think there's some stuff that could be causing problems in ultra-processed foods, like preservatives. And then we also know that eating a lot of red meat, especially charred meat and processed meats, are linked to some cancers too. Yeah, actually working on the ultra-process food episode, I stopped buying, like, lunch meat.

Oh, really? Like sometimes I'd have like turkey, sliced turkey meat. Yeah, I don't eat that anymore. slice turkey meat? Yes, because it has nitrates and nitrites in it. And that has been associated with cancer. What about cheese boards? Cheese boards. Does that count?

Oh, sorry, I meant like prosciutto and salami. Oh, we'd be like charqueterie boards. Yeah, yeah, yeah, charcutory boards. Once in a blue moon. I don't set out my spread of, you know, peeled grapes and charquotery boards every night anymore. Yeah. overall, it's probably a good idea to eat less of this stuff. And there are a few other risk factors that might be at play here, too.

Things like obesity, lack of exercise, smoking, and alcohol. But I kept thinking like there's got to be something else going on here because I keep seeing and hearing stories of people with very healthy lives that eat great, exercise a bunch, yet still getting colorectal cancer at a very young age. Here's Dr. Michael Foote, who we heard from earlier. Most of the people that we see are actually pretty healthy. I have a patient who was a vegan, you know, who came in. And she was, like, astounded.

She had an early-stage colon cancer, so we were able to remove it with surgery and then treat her, and she's doing well. But, you know, she didn't really drink very much. She didn't smoke at all. So, you know, that's kind of the scary thing, I think, for all of us. Yeah. I'm thinking about Becca, who we met earlier. she seemed very healthy. I don't know what she was eating,

but it didn't sound like she was sitting down to McDonald's for every meal. Yeah, similarly, Becker told me she wasn't big on processed foods or alcohol. I don't know. Like I said, I was 28. I was healthy. Like, I had just run a half marathon. I really wasn't thinking I might have cancer. My energy levels were fine.

I was still go, go, go. So what could be going on here? Lots of scientists are wondering if there's something else weird in the environment that people were exposed to that's maybe contributing to this or perhaps changed up the gut microbiome. They're on the hunt for explanations. So I want to talk about one of these ideas. Okay, great. One scientist we talked to is looking for clues inside the cancers themselves, like the actual DNA of these tumors. And his name is Professor Ludmil Alexandrov. And he's a cancer biologist at the University of California, San Diego. I actually specialize in cancer genetics,

in cancer genomics, and my focus is on understanding the processes that cause cancer. Several years ago, Lude Mill and several colleagues started this big study looking at the genetics of colorectal cancer tumors. So what they did is they collected a bunch of tumors from people who had this kind of cancer. And they ended up with almost a thousand tumors from across 11 different countries. Then they brought these samples back to the lab to test their genetic profiles. So Ludmille says inside a tumor, you can see these molecular fingerprints. These are made up of unique patterns of genetic mutations that can actually tell you a lot about that person's life. Molecular fingerprints, which we call mutational signatures, of what caused

the tumor. So for example, if you smoke tobacco cigarettes, you're going to mutate in a very specific way many cells of your body, for example, the lung. And we can say, this person smokes cigarettes. If you drink alcohol, you can see exactly the same thing. Wow, I didn't know scientists could do that. It's kind of cool. Yeah, I didn't either. I don't know what my cells could tell about me. I know, I was just thinking that.

And a good chunk of these samples were tumors that came from younger people. About 15% of all the samples we collected were early on set cases, which is a very large number. You wouldn't expect that number. When we were designing the study, we would expect it less. And 5%. Oh, so you weren't looking for that at the time. No, not the adult. Now that he had this data with all these younger people in it, he could compare the tumors

to see if there were genetic differences between the tumors and the younger and older people. To try and see, like, was there anything different that might help explain why the cancer is showing up more and more in young people? And he found that, yes, there was something different between these two groups. There was actually this particular set of fingerprints that stood out. And essentially the difference was striking. If you look at individuals who were younger than 40, more than 50% of them had these very specific patterns of mutations.

And when they looked into this specific pattern, it turned out that this type of mutation is often caused by certain bacteria that find their way into the gut. Okay. And what can happen is that bacteria that get into our gut can release a toxin called colibactin. Rose, what do you know about colipactin? Collie-backton. I don't know anything about it. Does it have something to do with cauliflower? No, it does not have anything to do cauliflower. Okay, well, that was my best guess. But it's something that gets made by some bacteria. Like, for example, some types of e-coli make it.

Oh, that's collie-coly. Yeah, it's more like coli-bactin than a collie. Collie flower bacterin. Coli-bactin. Yeah, yeah. And one thing that coli-bactin does, is it can damage our DNA because of how it works as a toxin. I think of it as a weapon system, a weapon system that certain bacteria have, and they use it to protect themselves from other bacteria. So this is like a weapon that the bacteria create for themselves?

Yes, exactly. So there's this bacteria scooting around in our guts, putting out this toxic substance. Yeah, I like that phrase, pudding, yeah. If a bunch of these bacteria get into your gut that make colibactin, when the bacteria encounter other bacteria, they'll start pooting or shooting this stuff out in all directions. It's like a little bacteria war, chemical warfare. Yeah, exactly. That's the theory. And some of that colibactin could be slamming into cells in the wall of your gut.

And that's where it can mess with your DNA. Oh, so that colobactin chemical warfare stuff, damages the cells of the gut. And somehow that damages your DNA as well? Mm-hmm. Yeah. To break it down a bit more, what happens is collie-backton can hit a cell

and then cause damage to the DNA in that cell. The cell will try to repair that damage, but sometimes it doesn't work. So you get mutations. And when that cell replicates, of course, those mutations replicate too. Mm-hmm. And so sometimes mutations do nothing.

Same thing with these colbybacting mutations, but other times they might be the first step toward a cancerous tumor. Right. But what's really interesting here is that Ludmill and his team were actually able to track down when these fingerprints were left behind because they could put together this genetic tree and track mutations over time. At a basic level, how it works is the trunk of the tree shows you the DNA's original state,

and then it hits a mutation grows a new branch. Then another mutation. another branch. This sort of thing allowed Lude Mill's team to put together an estimate of how old the person was when this mutation happened. Wow. Yeah. This detective works is fascinating.

Here's Lute Mill again. We always saw that molecular fingerprint in the trunk of the tree. And what that means is that happens very early. So studies have estimated that these coli-backing mutations happened when people were kids. Before they were kids, before they were

10 years old. Oh, before they even had the chance to start drinking or smoking or... Yeah, yeah. Wow. So the seed is planted very early. Which is, you know, super surprising. And even more surprising, Lundil says more recent work that's unpublished points to an even narrower window that it might

have happened. The more proper estimate is probably within the first two years of life. Oh, wow. So we think it's happening something in very, very early life. What we think happens is that when you have a young child, a year old, two years old, their microbiome and their immune system are getting formed, the microbiome in the colon. And if they get this infection, they get many, many mutations. And if you get many, many mutations at an early age, including some of the driving mutations that cause cancer,

then if you get it at age two, well, now you're on the fast track for cancer. get cancer in 20 or 30 years when you're a young adult? Two. Yeah, two. Oh, my God. This little baby. That's interesting. He says infection.

Does he mean this bacteria that poots out the, what was it, coli bactin? Is that the infection he's talking about? Yeah, when Ludmiel says infection, he's talking about this idea that some kind of bacteria ended up in these people's guts as little kids. Okay. Maybe E. coli, which is pretty common in our guts, maybe something else. And they put it out a bunch of this colibactin, and maybe that contributed to colorectal cancer developing years and years later. Wow. Yeah. Now we do have to mention here that it's correlation, not causation. We can't test this by putting this bacteria into a bunch of babies, you know. Yeah. But we do have studies in some mice showing that when you put coliabactering making bacteria in their guts,

they do get more tumors. So that's some more evidence of a potential link here. But let's assume that this is a real link. Do we have any idea, like, where this infection came from in the first place? So we don't exactly know. But Loodmill was like the things that babies are exposed to that can affect the microbiome does change a lot from one generation to another. Like younger people might have been exposed to more or different antibiotics.

Maybe it's related to C-section rates or breastfeeding versus forebohmobiotics. Or maybe it's as simple as like a lot of us, like everybody got exposed to a particular bacteria and it caused an infection and it just happened to do more damage if it happened to you as a baby. And I suspect that these microbes, some microbes that may be very harmless for us when we're adults are not that harmless for a one-year-old that's forming its immune system. Huh. Yeah. Like it could have been a pandemic, a very quiet pandemic that. some people are feeling the repercussions of now. Wow, that's fascinating. Yeah. And now this is just one possible contributor. Scientists are growing full steam ahead to try to solve this mystery. Other suspects include other types of bacteria, maybe viruses, also chemicals in the environment or medications like the antibiotics. That makes sense. So overall, we're getting a bunch of hints here,

but no clear smoking gun. And this means that, people like Becca don't have answers about where their cancer might have come from. But the good news is that Becca's doctors got her into treatment fast after she was diagnosed. So Becca had surgery. They took out the tumor, some lymph nodes, and more than a foot of her colon. Oh, man. And they got rid of all the cancer that they could find, but doctors also had her do chemotherapy last year. And after her last treatment, she celebrated with friends. Like they had a picnic in the park. I asked her what they had. Oh, gosh.

I think we just had a lot of cheese. It was really funny. I met with a dietician early on during chemo, and they actually told me to, like, eat a lot of cheese. That's a nice blessing. Yeah, say less. Like, I'll have no problem eating a lot of cheese. But she's not totally out of the woods.

I finished, in quotes, end of August. And so now people will ask, like, so you're done now, right? And it's like, yes and no. So Becca has to go back every three months for scans and blood work, and this part will last two years. There's a 25% chance of her cancer coming back during this time. So every three months, I get to be like a ball of anxiety and not know what's going to happen. But other than that, I'm just trying to, I don't know, focus on being here and feeling good right now. What do you wish you had known?

I wish I had a good answer for this. I don't know. I think the biggest hurdle for me was, like, getting over this fear of being thought of a certain way, right? Like, my life was kind of always going 100 miles an hour. And I feel like I had built a big part of my personality around, like, being this very independent person. And nothing will humble you faster than this experience. And so I think it was actually that first support group I went to with all of the, like, 70-year-old women. And one of them just told me, like, you have to learn how to let the love in.

Like, you have to. Like, you can't do this by yourself. And so I think I would tell myself, like, it's going to be okay. And, you know, your friends are going to show up in ways that you would never have expected. And, like, that's what's really going to get you through it is the people in your life. That's science versus. All right. Thanks, Michelle.

Thanks, Rose. Before we get to the citations, we've got a special sponsored segment for you with a very fun fact from the team. You're going to hear from Science versus producer Aketti Foster Keys. Here it is. This segment is brought to you by the all-new Audi Q3. Here's an impressive fact. The Q3 features a roomy, comfortable, refreshed interior with a 12.8-inch touch

Now, let's get to Dinner Party Genius. I'm a Keddy Foster Keys, and this is our segment, Dinner Party Genius, sponsored by Audi. I'm here with senior producer Merrill Horn. Hi, Merrill. Hey, Marrell. Hey, Katie. We're here to give you a fun science fact that will help you charm the crowd at your next party. Okay, Merrill.

So, the fact that I want to talk to you about comes from research that I've been doing about running for an episode coming out soon. and it's about really long distance running, like ultramarathons. Science is still figuring out what happens to our body when we run for super long periods of time. And it turns out, there might be something strange going on in our brains when we do this. Huh. So there was a small study that looked at runners who competed in a really long race. Like they went all the way from Italy to Norway.

Whoa. How long is that? It's close to 2,800 miles and more than 4,000 kilometers. Oh my God. Okay. So this is like forest gump level running. Yeah, exactly. Jeez.

And, of course, they got their brain scan along the way. Oh, so they popped into a brain scan during the run, got it. Right. And so when scientists looked at the scans, they found something that they weren't expecting to see. They saw that during the rain. these runners, their brains shrank a little. Ooh, that sounds bad. Yeah, it does sound pretty bad, right?

Yeah, their brains shrank, okay. Yeah, they lost on average about 6% of their green matter. But the good news is it wasn't permanent. Oh, okay, okay, well, that's good. The scientists also scan people's brains after the race, about eight months afterwards. and their brains had gone back to normal, like nothing had ever happened. So if you ever run over 2,000 miles, your brain might shrink a little bit, but don't worry, it'll all bounce back when it's over.

That's the fun fact. Yeah, it might shrink, but it might come back too. It will come back. Okay. Do you feel prepared for your next dinner party? Oh, yes, yes. I am so prepared with this fun fact. Yeah, I am ready for the party. Okay, thanks, Merrill. Thanks, Akkaddy.

That segment was brought to you by the all-new Audi Q3. Here are a few more fun facts. The all-new Audi-Q-3 features more power and more space than ever before. Plus, quadro all-wheel drive gets you there with confidence. It's built to impress. Kind of like you at your next dinner party. Say yes to the all-new Audi-Q-3, made for the yes-life. Learn more.

at AudiUSA.com. Okay, Rose, we're back. Time for citations. Can I tell you how many we have in this week's episode? You sure can. There are 72 citations, and where can people find them, Rose? You can find them in the transcripts of the episode, and you can find that by clicking a link in the show notes.

Cool. Thanks, Rose. Thanks, Michelle. This episode was produced by me, Michelle Dang, with help from Rose Rimmler, Merrill Horn, and Akkenny Fosser Keys. Wendy Zuckerman is our executive producer. We're edited by Blythe Terrell,

fact-checking by Erica Akiko Howard, mix and sound design by Bobby Lord and Bumi Hedaka, music written by Bobby Lord, Bumi Hedaka, So Wiley, Emma Munger and Peter Leonard. And thank you to Professor Caitlin Murphy. Science Verses is a Spotify studio's original, listen for free on Spotify or wherever you got your podcast. Follow us and tap the bell for episode notifications.

We'll factor soon.