Summary
This episode investigates why autism diagnoses have risen dramatically over recent decades, examining competing theories from environmental toxins to vaccines to screen time. The research reveals that the majority of the increase is attributable to expanded diagnostic criteria and improved identification of milder cases, particularly in girls and non-white populations previously underdiagnosed.
Insights
- Genetics accounts for 70-90% of autism susceptibility, but cannot explain recent rises since genetic prevalence hasn't changed; parental age contributes minimally (3-5% of cases)
- Environmental factors like air pollution, plastics, and vaccines show weak or no causal links to autism increases when examined rigorously
- The 'autism epidemic' is primarily a diagnostic expansion: severe autism cases have actually declined while mild/undetectable cases surged, indicating better detection rather than new disease emergence
- Historical diagnostic bias systematically excluded girls and non-white children; as definitions broadened post-1987, previously missed populations now receive accurate diagnoses
- Misdiagnosis of autistic individuals (especially women) as bipolar or personality disorders led to harmful treatments; proper diagnosis enables community support and better outcomes
Trends
Shift from categorical to spectrum-based neurodiversity models in clinical practice and public understandingIncreasing recognition of autism presentation differences across gender and race, correcting decades of diagnostic biasGrowing emphasis on neurodiversity acceptance and community support over pathologization of autismExpansion of early screening protocols in pediatric care driving earlier identificationReframing of rising autism diagnoses from 'epidemic' to 'detection improvement' in scientific discourseIntegration of parental engagement strategies (social interaction coaching) as evidence-based intervention alongside or instead of pharmaceutical approachesEmergence of peer-led support communities (e.g., Bargarita Moms) addressing social isolation in autism caregivingIncreased scrutiny of environmental toxin claims without robust epidemiological evidence
Topics
Autism Spectrum Disorder diagnosis and classificationDiagnostic criteria evolution (DSM revisions 1980-1987)Gender bias in autism diagnosis and misdiagnosisRacial disparities in autism identificationEnvironmental toxin exposure and neurodevelopmental outcomesScreen time effects on child developmentParental age and genetic risk factorsAir pollution and prenatal exposurePlastics and PFAS chemical exposureVaccine safety and autism causationEarly intervention and behavioral therapyNeurodiversity and social acceptanceEpidemiological surveillance methodsPsychiatric misdiagnosis in autistic populationsHealthcare screening and detection protocols
Companies
Centers for Disease Control and Prevention (CDC)
Released latest autism prevalence data showing 1 in 31 children diagnosed, catalyzing public debate about rising rates
Drexel University
Multiple researchers (Brian Lee, Karen Heffler, Deena Gassner) conducted epidemiological and intervention studies on ...
University of Wisconsin-Madison
Epidemiologist Marnie Durkin presented research showing severe autism cases declined while mild cases increased
UCLA
Catherine Lord, diagnostic expert, developed widely-used autism diagnostic instruments and discussed diagnostic evolu...
People
Robert F. Kennedy Jr.
Health and Human Services Secretary claiming autism rise is caused by environmental toxins; disputed by researchers
Catherine Lord
UCLA professor and autism diagnostic expert who developed diagnostic instruments; traced evolution of autism definition
Brian Lee
Drexel epidemiologist explaining genetics' 70-90% role in autism and parental age contribution to prevalence
Karen Heffler
Drexel researcher studying screen time effects on autism; conducted pilot study reducing screen exposure
Marnie Durkin
University of Wisconsin epidemiologist whose data showed severe autism declined while mild cases increased
Deena Gassner
Drexel researcher and autistic individual misdiagnosed with bipolar until age 40; founded Bargarita Moms support group
Wendy Zuckerman
Science Vs host and producer investigating autism prevalence claims and scientific evidence
Meryl Horne
Science Vs senior producer conducting interviews and research for autism episode
Quotes
"Vaccines do not cause autism, full stop. It has been studied, it has been taken seriously, it has been studied. And, you know, various different vaccines, various ingredients in vaccines. And no, we cannot see a link here."
Brian Lee•~25:00
"I think it accounts for most of it. And I think all of us worry that we're consuming plastics and things that we, you know, that we wouldn't choose to eat or breathe, but that can't account for most of what's gone on."
Catherine Lord•~55:00
"That's fantastic. So for Deena, it was like the start of really understanding who she was, and it also helped her find a community of other autistic people."
Wendy Zuckerman•~70:00
"When we experience access to communication, unconditional love, and meaningful, usable supports, we have healthy, well-adjusted, but autistic people. And that's a good thing."
Deena Gassner•~75:00
"The biggest increase was those with no actual measurable functional limitations."
Meryl Horne (describing Marnie Durkin's research)•~50:00
Full Transcript
Hi, I'm Wendy Zuckerman and you're listening to Science Ferses. This is our last episode. For a little bit, we're going to take a short break until September while we work on new episodes. So that means if you have an idea, something that you want us to versus, you've got to tell us. There's a lot of ways to do it. You can do it on social media, Instagram, TikTok. There's an email address. It's all in the show notes. So if you've got an idea, something that we have to versus, please let us know. We absolutely love hearing from you. Now on with the show. Today's episode is all about autism because we're asking, why do so many folks have it these days? Rates of autism have been going up and up for decades. But then a couple of months ago, the CDC released the latest numbers, catapulting this issue into the spotlight. A brand new report out today from the Centers for Disease Control finds a dramatic rise in autism diagnoses among children. An alarming spike in the number of children diagnosed with autism. New data just released shows a 15% jump in just two years. The CDC report found that one in every 31 kids looked like they now had autism, which is nearly five times more common than it was 25 years ago. And the rates in boys were even higher. Health and Human Services Secretary Robert F. Kennedy Jr. says, this is an epidemic. This is part of an unrelenting upward trend. Revolence two years, the answer is very clear. And this is catastrophic for our country. And it's not just in the US, in Japan, Canada, Australia, Europe, rates of autism have been going up too. And now there is this huge fight brewing as to what's behind this. Why do so many people have autism these days? RFK Jr. reckons... This is coming from an environmental toxin. And somebody made a profit by putting that environmental toxin into our air, our water, our medicines, our food. There's all these different theories about what's causing this, from vaccines to pollution and a whole bunch of other stuff. Can more screen make your child autistic? A new study says yes. It might be microplastics, the forever chemicals. Living in an area with high levels of air pollution may be linked with a woman's chances of having a child with autism. But then there are folks saying, whoa, whoa, whoa, whoa! There's actually a much simpler explanation here. And it all has to do with how we diagnose autism in the first place. So who's right? What is going on here? At a recent press conference, RFK Jr. said that we're going to start to have answers on the root cause of this epidemic by the end of the year. But Christmas has come early, because today on the show, we are going to find out what's happening. When it comes to the rise in autism, there's a lot of fingers pointing at lots of different things. More screens. Microplastics. But then there's science. Science vs Autism is coming up just after the break. This episode of Science vs is presented by Audi. We all know that feeling, a change of plans, a new opportunity. Instead of overthinking, what if you just said, yes? With the all-new Audi Q3, the answer is easy. It's made for the yes life, with the power and room to handle whatever pops up. Yes to adventure, yes to right now. Because saying yes without hesitation, that's real luxury. The all-new Audi Q3. Made for the yes life. Learn more at AudiUSA.com. This episode is brought to you by Claude from Anthropic. Some of the greatest innovations came from someone just wanting to help. The scientists who founded Anthropic wanted to build AI that's safe and benefits humanity, and Claude is where that research comes to life. Claude doesn't just hand you quick answers, it thinks with you. Digging into complexity, flying contradictions, and helping you work through the nuance. Which, if you listen to this show, you know is where the real science lives. See why problem solvers choose Claude as their thinking partner at claude.ai.scienceverses. Welcome back. Today we're looking at autism and finding out why the numbers of people being diagnosed with it have been going up and up. To tell us all about it, we have Senior Producer Veryl Haud. Hey Veryl. Hey Wendy. Alright Veryl, can you just tell me what exactly is autism? I just feel like people kind of throw it around, diagnosing their friends with it, their friends' children with it. You know what I mean? What are we talking about here? Well it can show up for different people in different ways, but generally a lot of autistic people will have a harder time communicating, so that's a big theme. And then there's other stuff that shows up a lot too. Like you might have really specific intense interests, or a harder time when your routine is disrupted, or more intense reactions to really annoying stimuli, like really bright lights or loud noises, that kind of thing. And then our big question of this episode is why do so many more people have it these days? Yeah, what is going on? When I started talking to scientists about autism in general, about what causes autism, there is one thing that came up right away. Genetics is sort of the elephant in the room that you can't ignore. Genetics. Yeah. So this is Professor Brian Lee, epidemiologist at Drexel University. And he said that a huge part of whether somebody will be autistic is just passed down to you. It's in your genes. And we know this from looking at studies on families. So like if we know of one sibling has autism, the other siblings are more likely to also have it. And then if you look at identical twins who basically have, you know, the same DNA, it's like even more likely that if one identical twin has it, the other one is really likely to have it too. And so based on all of that, scientists have kind of figured out how much of autism is inherited. And it's somewhere between 70 to 90 percent. Whoa. That's huge. 70 to 90 percent. Yeah. And we don't really know like all of the genes that are involved. Like sometimes it might be that there are like hundreds of genes that are kind of all working together to up that chance that someone will have autism. Other times it'll just be like one particular kind of genetic quirk. But yeah, it's genetics is huge. I guess in the context of this rise in numbers that we're seeing though, genetics can't explain why so many folks would be diagnosed with autism now, right? I mean, because why would we suddenly have so many more autism genes in the population? Well, actually there is one thing that has changed. So parents are having kids at older ages now. And that might be introducing genetic changes that can like up the chance that their kids will be autistic. And so older, how old are we talking here? Well, Brian has studied this and so he did like a back of the envelope calculation with the latest numbers for me. Okay. So overall in the U.S., about 3.2 percent of kids are autistic. So that's kind of like the baseline chance on average for autism. Yeah. So one in 31 kids. Yeah. It works out as a 3.2 percent. Okay. But if you're a mom over 40, we think that the chance goes up from 3.2 percent to something like 5.6 percent. That's not nothing. And then what about the other side of this, the spurt? It's actually a smaller increase for the dads. But yeah, it still goes up a little bit. So could this explain why we're seeing higher rates of autism across the country and around the world? Well, a lot more people are having kids later in life. Like the percentage of births to women who are older than 40 has basically tripled since 1990. But overall, it's still a really small percentage of like total births. It's like 4 percent of all the births in the U.S. are from moms in their 40s. So I asked Brian, like at the end of the day, how much does he think this older parent thing can really explain the increase in autism cases? It's certainly going to contribute some portion, but it's not explaining the lion's share. It's not going to explain the lion's share. Okay. So what else could explain the lion's share? We've got like the meerkat's share covered. Lion's share still out the open. Right. So that's the big question because, yeah, genetics might like kind of set the stage for whether or not someone will have autism, but there is this idea that maybe you need like a trigger to actually make it happen. And scientists have been finding lots of things that might sort of be that trigger and up the chance that someone will have autism. A lot of the things we're finding kind of come into play when someone's a fetus. So things that happen during pregnancy and utero. So like if a mom gets an infection, if there's birth complications, taking certain medications while you're pregnant, like there's an anti-seizure medication that will up the chance that someone will have autism. But like a lot of that stuff doesn't really explain why autism would suddenly be more common in the last few decades, right? Oh, because pregnant folks aren't taking more of those meds. No. Yeah. Experts told me they didn't think that this stuff would make a huge dent. There's maybe one exception to this, which is that if you're born prematurely, like very prematurely, you're more likely to have autism. And there are more premature babies that survive now. So maybe that's contributing a little bit to the rise. But the researchers I've talked to say that like, oh no, this is such a small proportion of people with autism that like that really can't explain these huge rises that we are seeing either. Okay. So then what about these things in our environment? The stuff, I guess, RFK Junior talks about environmental toxins, which he said could be in our air or our medicines. And I suppose we could put plastics in there too. What do we know here? Yeah, we asked RFK's team about what specific environmental toxin he was talking about. And a spokesperson told us that quote, everything is on the table. So I asked Brian about this when RFK Junior was talking about why autism is so pervasive. He said, quote, this is coming from an environmental toxin. What do you make of that? I know of his weird conspiracy theory type attitudes on vaccines. And I'm wondering if that's code for we need to do another vaccine study. And if that's what he means, I would be very horrified because that would be a tremendous waste of money to go basically beating a dead horse at this point. Vaccines do not cause autism, full stop. It has been studied, it has been taken seriously, it has been studied. And, you know, various different vaccines, various ingredients in vaccines. And no, we cannot see a link here. But there are other potential things that are in our air and our water that probably weren't 25 years ago, right? Yeah, no. And there is a lot of research looking into other stuff that, you know, is in our environments and might be linked to autism. Brian said that one kind of hot area of research is air pollution. Like a big review just found that there might be a link between being exposed to certain types of air pollution during pregnancy and the kid later having autism. Oh, how would that happen? So pollution are these tiny little particles, right, that we breathe in and it could be that they're getting past the placenta and into the brain as it's developing. And then maybe kind of changing the brain, like maybe through oxidative stress or neuro inflammation. But the kind of pollution that's linked to autism has generally been going down over the last couple decades in the US. So like that doesn't explain why it's been going up. And it's sort of similar with heavy metals, which is something a lot of people on the internet are worried about right now. There is some research that says maybe getting exposed to lead, for example, might up the odds for autism. But lead and other heavy metals have generally been going down. Oh, okay. So plastics, plastics have been going up, right? Yes, plastics have been going up. And there are a lot of studies that have looked at a potential link between plastics and autism. So researchers will look at the blood or pee from a pregnant person and look for chemicals like phthalates or PFAS or forever chemicals. And then they'll ask, like, are the kids who are exposed to more of this stuff in utero, are they more likely to show signs of autism later after they're born? Yeah, yeah, yeah. And what do they find? A few studies say yes, but the vast majority of them find no connection. Mmmmmm. So, okay. There's no smoking gun here, thus far, for the lion's shit, because maybe in cases here or there, but we are looking for something that could really explain, like, quite a large number of people now being diagnosed with autism that were not before. Screens is the other thing being thrown out. What do we know here? Yeah, I looked into screens and was surprised that there actually was some research on this. Why? Why would you? I don't know. People blame everything on screens and I was just like, I don't really buy it. But then, like, let me tell you what happened, though, when I talked about it with this researcher. Uh-huh. I'm Karen Heffler. I'm a researcher at Drexel University. And unlike me, Karen was like, well, it actually makes total sense to look into screens, particularly when you look at the timeline here. How has the world changed over this period of time? Babies, children used to be first exposed in the 70s at about four years of age. That's the first time they watched any television. By about 2006, it was at four months of age. But it's not just that the timing fits here. There is some evidence linking screens to autism. Like, there are studies that have found that kids who are exposed to more screen time when they're really little, maybe like a few hours every day when they're one or two, those kids are more likely to either show autistic traits later or even be diagnosed with autism later in life. And that's not that much screen time. One or two hours, right? Yeah, like some studies find even that much might make a difference. And then Karen did this really interesting pilot study looking at whether getting families to like cut down on screen time might decrease their autism symptoms. Right. It was really, really tiny, so they only had nine families. But I thought it was interesting because what they had them do was pretty dramatic. So they chose families with autistic kids who are watching a lot of screen time. So before the study started, the screens were on for an average of five and a half hours every day. Wow. Then during the study, it was six months long, they got them to cut it down to like five minutes of screen time a day. Not even a full episode of Bluey. No, exactly. And so she looked to see if this had an effect and it seemed like it did work. So kids had a decrease in some autism related behaviors by the end of the study, specifically in social skills and repetitive behaviors. So before the study, the children at the beginning, a lot of them didn't really pay attention to their parents. They might be spinning wheels on a car or lining up items or just distracted with sensory like flapping or looking at lights. Not really interested. And then after basically no screen time, the eye contact got better. They wanted to be with the parents. They started paying attention to people. Mmm. That feels promising. Yeah. But then Karen told me about something that really changed the way that I thought about the study. So cutting down on screens was a big part of the study. But it wasn't just turning off the screens. We met with them for one hour every week and worked on strategies to help them engage their children socially. So eye contact, so if a baby coos or babbles, then the parent would smile back or maybe, you know, imitate the child. Or we would suggest that they hold interesting items to their children up to their eyes. And if the child looked at them, then say, oh, great looking. Oh, I love to see your eyes. Really positive reinforcement. And so from other studies, do we know that that kind of positive reinforcement with a kid with autism helps them? Like would you expect to see these results if you forget the screen chat and you just do the positive reinforcement? Yes. I have a very satisfying study for you now because Karen told me about a study where they basically did that. Oh, OK. So this one was a larger, proper randomized controlled trial with about 100 really young kids. And they had started to show some signs of autism. And what they did in the trial kind of reminded me of a lot of the things that Karen did in her study. Because it was like teaching the parents how to pay attention to their kids really closely, responding to them and interacting with them. Right. But they didn't tell them anything to do with screens. Perfect. Great. OK. So then what happened? Well, fewer of those kids were diagnosed with autism later. So then what do you think? How much do you think screens are playing a role here in this so-called autism epidemic? Well, it is a little tricky because there are also other explanations why we might see a link between screen time and autism. Right. Like we know that a lot of kids who are autistic really enjoy watching screens. So maybe it's just that someone's already autistic and then maybe their parents put the TV on more for them because they see that they're really happy. But like that's not to say that screens are totally innocent here because like you can also imagine that like maybe there's a kid who is already on the autism spectrum and is watching like hours and hours of screen time every day instead of interacting with other people. Maybe they're more likely to end up with an autism diagnosis because their social skills aren't getting like a workout. That makes sense. But I think bottom line, you don't seem to think there's evidence that screens are really behind this epidemic, you know. Maybe a little bit, but it's really hard to say how much. OK. So here's where we're at. I don't know. I feel like we have not gotten that lion's share of these cases yet. I mean there's more me and cat dinners here and there. But we're missing something big still. Yeah. Yeah, that's what we're going to look at after the break. Something big. Zep bound is an injectable prescription medicine that may help adults with moderate to severe obstructive sleep apnea, OSA, and obesity to improve their OSA. Zep bound should be used with a reduced calorie diet and increased physical activity. Zep bound is approved as a 2.5, 5, 7.5, 10, 12.5 or 15 milligram injection. Zep bound contains tersepite and should not be used with other tersepite containing products or any GLP1 receptor agonist medicines. It is not known if Zep bound is safe and effective for use in children. 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Zep bound and its delivery device base and quick pen are registered trademarks owned or licensed by Eli Lilly & Company. It's subsidiaries or affiliates. This episode is brought to you by Focus Features. Would you let AI pilot your plane? Raise your child. Decide your future. On March 27th, Focus Features presents the AI doc or How I Became an Apocalypse Optimist. Critics and audience at the Sundance and Southwest Film Festival call it the most urgent movie of our time. The AI doc or How I Became an Apocalypse Optimist rated PG-13 only in theaters March 27th. Welcome back. Today on the show, autism, what is causing the rise in cases. We talked about how there's a lot of things people are pointing the finger at from plastics, which is maybe play some role here, but it's definitely not a slam dunk. Vaccines are a no, screens are a maybe. People having kids when they're older playing some role here, but not that much. Meryl, you've promised me something big. Yeah. The lion's share. I feel like we've earned it. Yes. Well, so one idea is that this actually just has to do with the way we're like deciding who has autism and who doesn't. And that basically we've decided a whole lot more people who would otherwise not be classified as having autism now all of a sudden, you can join the party as well. Yeah. Yeah. And this is something that RFK Jr. really rallied against in his speech. He said that the idea that we are somehow like not catching all these cases in the past is like actually kind of insulting to the doctors who were practicing back then. Doctors and therapists in the past were not stupid. They weren't missing all these cases. The epidemic is real. So to get to the bottom of this, I decided to call up a scientist who has been diagnosing autism for decades. This is Catherine Lorde, professor at UCLA. Did you ask her if she was stupid? Yeah, that was my first question. But actually my first question was about something else. I was told by one of your colleagues that you are the diagnostic queen when it comes to autism. Oh dear. Well, with other people not single-handedly by any means, I work to develop the most commonly used diagnostic instruments that people use when they diagnose autism. That's where that came from. She's also the diagnostic queen because she's been in this field through the absolutely wild changes that have happened over the past few decades when it comes to how we do this, how we diagnose autism, which I know it kind of sounds like a snoozefest, but it's actually the story of how our understanding of what autism is has evolved. So let's start in the 1960s. Back then, we weren't even sure if autism was its own thing or if it was part of schizophrenia. Oh. And this is kind of what we thought autism looked like then. I mean, I think in the 60s, a person with autism would often be not verbal, like not talking, and would be quite severely intellectually disabled. We were very focused on things like flapping your hands and looking at your fingers and the things that you can see right away. This is when Catherine got into the fields as an undergrad, and she loved working with autistic kids and finding ways to connect with them even when they weren't verbal. But then sometimes a kid would come in who would really challenge the idea of what someone with autism was like. Catherine remembers this one kid. Oh, I saw this little boy who had all kinds of language that just poured out of him. And in those days, we had them parents sit in another room and watch us. And so he was not happy about that at all. He was about four. And he had a lot of repetitive language, and his nose was running. And he started talking about, I don't want to be a rainbow. I don't want to be a reindeer. I don't want to be a reindeer running reindeer. I don't want to be a reindeer. And what he was talking about was he was crying and his nose was running. And he had these phrases, and he was trying to figure out how to say, you're making me cry. And people were like, boy, I don't know if he could be autistic. And he was as autistic as you could be. So what made him, what else about him made it clear that he had autism? Well, now we know that it's not necessarily that you don't have any language at all, but the way he used language was really different. Like he would often repeat phrases over and over again. And so, yeah, it's not as simple as we thought. And so that was the 1960s. But that's kind of like limited definition of autism stuck around for a really long time. That you needed these severe traits. Yeah, like really severe traits. And it was often accompanied by intellectual disability. But then even in 1980, this is when you see autism get its own entry in the DSM, which is the Bible for diagnosing psychiatric conditions. So now it's like, it's not part of schizophrenia anymore. We got that right. But the description of autism is pretty intense. Like it says, quote, this disorder is extremely incapacitating, unquote. But then there's kind of a turning point. The next version of the DSM comes out in 1987. So by then, scientists had started to think about autism as like a looser kind of collection of traits. Like we still think that having trouble communicating is like a hallmark of autism. But maybe it's also that you're really interested in a specific thing. So getting very focused on something, you know, that could be anything. I mean, it could be the same things other kids are interested in. So, you know, dinosaurs, but it also could be Scottish clans. Or we had somebody who loved newspaper editors. He was an expert on who were the editors of the major newspapers and could recite that. So it's not bad to have an interest. It's just that not being able sometimes to reign it in if other people are not so interested. So this is, I mean, the late 80s is exactly when Rain Man came out. Yeah. Right. And I mean, I'm sure with 2025 eyes that movie does not hold up well. But it does show how much the image of autism, at least in the public's imagination, changed so much already by then. You know, he was a character that was a genius in some respects. I mean, like he could memorize the phone book, right? Yeah. And just generally we end up getting to this place where just because you're autistic doesn't mean that you're incapacitated. Like it used to be described like in some cases you might be better at things than neurotypical people. And so we can see this expanding and expanding definition of autism. And there also kind of going along with this, we used to think that Asperger's syndrome was something different. Right. Oh, yeah. And now that's been rolled right up into autism spectrum disorder. It's all part of the same thing. Uh-huh. Right. But I feel like this idea of what autism is is still changing right now. It's like the tectonic plates are still shifting and in another 50 years it could just look different again. So what is the sort of suggestion here is that this autism epidemic, these new cases of autism, it's actually just because we have changed our definition of autism. We're not just capturing these folks who have real difficulty verbalizing, communicating, maybe also happen to have severe intellectual disability. We're now opening up the definition to include folks who are neurodivergent in more subtle ways. Yeah. And but that would mean you should be able to see that in the data, right? And yet RFK Junior says that most of the new cases are quote, severe, which would go against this idea that, oh, it's just our changing diagnosis, right? Yeah. He's kind of like, no, now is when we're seeing all these severe cases. Like he painted this really dark picture where he called this a tragedy and said that quote, autism destroys families. Most cases now are severe. So about 25% of the kids who are diagnosed with autism are nonverbal, non-toilet trained. And yeah, that's like in pretty stark contrast to this idea that autism is actually just going up because of this definition kind of expanding. Yeah. So who's right? I mean, do we have any numbers here? So a couple of researchers told me like, oh, you have to talk to Marine Durkin because you just presented this work at this huge autism conference that looks at that exact question. Oh, cool. So yeah, she's an epidemiologist at the University of Wisconsin, Madison. Hi, Meryl. Can you hear me okay? Hi, I can hear you great. So Marine basically found a new way to like dig into the data to look at what kind of kinds of autism cases are the ones that have been going up. Great, great. So she did this. These are eight year old kids from across the country and the kind of timeframe she's looking at was from 2000 to 2016. And what she does is kind of divide autism cases up into different buckets where on one end you have what people might think of as like severe autism. So this is somebody who needs a lot of help when it comes to stuff like going to the bathroom, getting dressed, communicating their needs, that kind of thing. They're like day to day functioning. Yeah. And so actually let's start there and find out like what Marine saw when she looked at those kids over time. This group? Did not increase at all. It did not. In fact, it declined its site. Whoa. But it didn't increase. Did not increase. Mm-hmm. And when she looked at what cases were going up, it was a totally different group of kids. The biggest increase was those with no actual measurable functional limitations. Oh. Yeah. The biggest increase was in that group because that was a very small group in 2000. Mm-hmm. Yeah. So. Right. So there are kids who are autistic who don't actually need any more help than neurotypical kids in their day to day life. And then Marine also saw a rise in kids who maybe need like a little bit more help. And this research isn't out in a journal yet. It's a peer review now. But she presented it at this conference. So let me show you this graph that she presented there that kind of made a big splash. Uh-huh. So this is looking over time from 2000 to 2016. Oh yeah. And you can see really clearly that the severe cases, they have dropped a tiny bit, maybe barely statistically significant. She got the error bars there. But it's really these milder forms. That's what's, that's the lion's share, Meryl. Yeah. We found it. We found it. We found it. We found it. So I asked Marine, and so these were the cases that we were kind of missing decades ago. It appears that. Well, we know that's true. That as the definition of autism has expanded over time, we're including a wider spectrum. We did reach out to RFK's team to ask them what they made of this research. They didn't address that question, but instead they doubled down on the idea that there is an environmental toxin that's causing this. I also asked Catherine Lorde about this. If we are labeling more people today with this label, how much does that really matter when it comes to explaining why it looks like autism has gone up? I mean, I think it accounts for most of it. And I think all of us worry that we're consuming plastics and things that we, you know, that we wouldn't choose to eat or breathe, but that can't account for most of what's gone on. So, yeah, in a press conference recently, Health and Human Services Secretary Robert F. Kennedy Jr. basically kind of poo pooed this idea that it is just about changing diagnosis. So, is he wrong? Yeah, I think he's wrong. And there are other things that might explain why we're seeing more and more cases of autism. Like it's become standard to screen kids when they go to the pediatrician for autism. There's also just more awareness. A lot of researchers told me they think that could be playing a role here. Right, yeah. And that leads me to the final thing I wanted to mention, because like now that we've got this bigger understanding of autism, of what it can be, it's really shifted the picture of what an autistic person could look like. So, in the past, there is a strong bias towards diagnosing boys with autism. The hardest thing was that if you're female, you're not autistic because it's very, very rare. So, this is Deena Gassner, a researcher at Drexel University. And yeah, she told me that she's autistic and she wasn't diagnosed until she was 40. And she said that for so long doctors had this idea that autism was pretty rare in girls, where today you see that ratio sort of leveling out. And it also used to be more common to get diagnosed with autism if you were white, but those numbers are also leveling out. So now in the U.S., white kids are not more likely to be diagnosed with autism compared to other racial groups. And it's not necessarily that these people weren't getting any diagnosis at all. In a lot of cases, they were getting misdiagnosed with something else. This happened to Deena. I was misdiagnosed with bipolar. Oh, wow. And that is not uncommon. Bipolar and personality conditions are often diagnosed in autistic women before they get their right diagnosis. And the problem with that is the medications that come with that. Yeah. So for Deena, even though she never had bipolar, she was put on lithium. What did the lithium feel like? Oh, I was completely dysfunctional. I just wasn't a human being for that timeframe. And so I finally found a doctor who was actually treating my children who said, I think you might want to reevaluate where you are. And he saved my life. Gosh. Researchers have told me that this is actually kind of a common thing, that a parent will take their kid in to get diagnosed with autism, and then they'll walk away with their own diagnosis that was missed years ago. Oh, right. Which goes back to this idea that genetics is so important to this epidemic that we're seeing, because now instead of one case, you have two cases. Yeah. But it's funny, we keep using that word epidemic to describe what's going on. I don't think that's actually the right word to describe the rising cases. Lots of scientists have told me that the real epidemic here is that we are failing so many autistic people who need better services that there's an epidemic there. But the idea that the rising cases is in and of itself a tragedy or an epidemic, I asked Deena about that. How do you feel about the fact that we're seeing more and more people being diagnosed with autism today? That's fantastic. Yeah. So for Deena, it was like the start of really understanding who she was, and it also helped her find a community of other autistic people, and also other moms of autistic kids, since her son is autistic too. I was seeing that mothers of autistic kids were often abandoned by their girlfriend network, and we need nurturing, and we need community. And so I started a group called Bargarita Moms. And we drank margaritas, and we went to see Magic Mike. And our rule was you're not allowed to talk about your child, but you can talk about your undiagnosed husband. And we had fun. And so we're seeing this rising army of these really neurodivergently intact, healthy, well-adjusted autistic kids that are coming up. And my grandma jeans get all fired up. I'm like, oh, it's so awesome. Let me see your child dancing to Taylor Swift. It's joy. It's autistic joy that's coming out of this newer population. And so that's why much of our community is pushing back on these highly stigmatizing languages, assigning tragedy mindsets to this population. When we experience access to communication, unconditional love, and meaningful, usable supports, we have healthy, well-adjusted, but autistic people. And that's a good thing. Yeah. Well, we've solved the case of the so-called autism epidemic. Yeah. Merry Christmas. Thanks, Merrill. Thanks, Wendy. That's Science Faces. So Science Faces is going to be on a little break until September while we work on new episodes. And I thought to celebrate this last episode of the season, I would invite the team to our satations chat. Yay. Bye, everyone. Bye. Bye. No. And a baby. And a baby's here, too. How many satations are in this week's episode? Sixty. Sixty-eight. Sixty-eight. Sixty-eight. Okay. And, Keri, what was your favorite moment of the season? I think my favorite moment of the season has to be meth. Ooh, meth. I just laughed. It's like new vocal stim. I say it at least like a couple of times a week for sure. Michelle, favorite moment? I really loved bird flu and learning about manure lagoons. That was just the weirdest fun fact in the world. Fun? I just have to pick the fact that we finally made our episode on squirting. Of course. It was just a delight. And it was a long time coming. Ooh. Merrill? I have to say the carnivore diet episode last week was just so fun. Something about the top, it was just so like bro-y and hardcore. I just like it really made my dopamine flow. All right, then to cap us off for this season, we'll be back in September. Waste the editing touch to pitch us ideas. Are all of the show notes. Please do that. The satations link to the transcript. It's also in the show notes. But to cap us off, all right, everyone, let's say primal. Primal. Primal. Primal. Primal. Is there a better word, is there a better science word? Here, reviewed literature. Thank you so much for listening and we will see and you will hear us very, very soon. Thanks, guys. Bye, buh-buh-buy. Bye. This episode was produced by Merrill Horne, with help from me, Wendy Zuckerman, Katie Foster Keys, Michelle Dang and Rose Rimmler. We're edited by Blythe Turrell. Backchecking, research assistants and consulting by Erika Ikeko-Howard. Mix and sound design by Bobby Lord. Music written by Emma Munger, So Wiley, Peter Leonard, Boomi Hidaka and Bobby Lord. A special thanks to the researchers that we reached out to, including Professor Karen Pierce, Professor David Mandel, Professor Deborah Bilder, Professor Frederick Bonnet-Brio, Dr Helen Tager Flussberg, Dr Isabella Delalara, Catherine Byrne, Professor Sven Balté and Dr Whitney Warsham. Special thanks also to Lynn Keys and Bella Veseka, Chris Souter, Elysean Dillon, Jack Weinstein and Hunter, Joseph LaVell Wilson and the Zuckerman family. Science Versus is a Spotify studio's original. Listen to us for free on Spotify or wherever you get your podcasts. We are everywhere. If you are listening on Spotify, then follow us and tap the bell icon so you get notifications when new episodes come out. We'll be back in your ears in September. And I'm Wendy Zuckerman and I'll back to you then.