Wendy Zukerman
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Hi, I'm Wendy Zuckerman.
And so I asked Justin, so if you don't ejaculate, you don't get that sense of relaxation, which some may interpret as tiredness, you would...
And so there have been studies that have actually looked at this in terms of sports performance.
So, for example, there's this research that basically gets guys, it's all, I think it's all men in these studies, that tells them not to have sex the night before.
And then they'll test whether they can lift more weights or cycle faster.
Giving it to a sock.
Or my favorite, test their grip strength.
And so I asked Justin, what have these studies found?
It doesn't affect it.
It's funny because it is true that for thousands of years, men in particular have been conflicted over whether to fap or not to fap.
Your energy, you'd wasted your seat.
You'd wasted your energy.
There is one sort of exception to this idea that perhaps it doesn't matter that maybe might make you feel better about your thinking around gigs.
And so the study, Justin's actually referring to one particular study.
It was a study of 15 male athletes randomly assigned to have sex and ejaculate or not have sex.
And then two hours later, they basically had to go on this like fancy exercise bike.
And ride as hard as they could go while their heart rate was being measured.
Now, interestingly...
And whether they had sex or not, it didn't affect how hard they could go on the bike.
But after, in the recovery phase, their heart rate was a little bit higher.
And for some in the ancient world, semen was seen as this powerful thing, sometimes this great powerful thing that could do super impressive stuff, like apparently the Sumerian god Enki came and that's how we got the Tigris and Euphrates rivers.
And some of them said the exercise bike, even though they could do it, it was a bit tougher.
Two hours, sure.
Yeah, maybe it's relevant.
Ten hours, night before, you were absolutely fine.
Great question.
So hormonally, not really.
So both when studies look at whether your prolactin, oxytocin, testosterone levels rise after sex versus after masturbating, they all see the same pattern.
That like oxytocin goes up, prolactin goes up, testosterone goes up.
So that was the closest I could find.
Probably on a psychological level, it does make a difference.
I would imagine that people feel differently after...
Just after sex with someone else.
And just quickly, I also looked at whether abstinence can boost your mood.
People talk about how it can help with depression, anxiety.
And studies have looked into this.
So one study compared 44 men who didn't masturbate for three weeks with guys that did.
You're listening to Science Versus.
No difference in mood.
But the nofappers did feel more self-control on average.
There is this other study that looked at guys who were on a forum for trying to break pornography addiction.
And in doing this, a bunch of them also tried to stop masturbating or orgasming at all.
And they wrote these abstinence diaries that researchers then analyzed.
And some men, they did really value this activity.
So one 21-year-old said he did feel more happiness.
And another wrote, I just feel on a deeper level.
With work, friends, pastimes, there have been waves of emotion, good and bad, but it's a great thing.
This is what I think.
This is what I think.
And speaking to Justin and other researchers, it definitely feels like it's...
more psychological.
You didn't like how much you were masturbating or orgasming and now you've been able to control yourself and that's why you feel better.
But then on the other hand, it's like this conflict between
But I do think in these forums...
Yeah, what they're getting wrong is they're kind of blaming what masturbating is doing in your body.
Blaming the physiology of like if you masturbate, it's sapping you from energy, hormones that you need, blah, blah, blah, when I think it is really more of a mental thing.
I think that's where we're at.
that we've had for so long because then you've got Hippocrates and Taoist mystical practitioners and then the 18th century you've got philosophers and the 19th century you've got American doctors all on team cockblock saying that things like masturbation and losing your semen weaken a man's body and brain.
Welcome back.
Today on the show, should you try to stop...
ejaculating for a month more.
We've just learned it probably won't bump up your testosterone levels or give you more energy, but now we're finding out, can it boost your sperm quality?
For this, we need Brent Hansen.
He's a reproductive endocrinologist and fertility specialist at CCRM Fertility of Minneapolis.
How many people's sperm have you looked at?
Can you paint a picture of when you're looking at the sperm under the microscope?
What's a sample that makes you really happy?
That you're like, this is a great...
Sample of swimming.
So the question is, how do we make Brent happy?
We want to swarm.
How do we get the swarm?
It's important because a lot of folks are struggling with fertility issues right now.
Sperm counts have been going down.
So could saving your seed and not ejaculating be the answer here?
And Brent did this big review paper looking at this.
And a big reason he did it is because when patients would say, you know, we're struggling to have a baby, how long should I be waiting here before I come into my partner?
He didn't have a great answer for them.
It feels like, it doesn't feel like dark matter, you know?
It feels like something we should get a handle on.
No-brainer, right?
So Brent and his team looked at more than two dozen studies on how abstaining from ejaculating could affect various things related to sperm.
And so I actually didn't realise how many different things can affect the quality of your sperm, but I asked Brent to list them.
Semen volume, that's just how much gunk is coming out in total?
Oh, what do you think we should use instead?
Yeah, anything else we could go for?
But semen you might leave around for a little bit.
Yeah, we don't want to add to the guilt around this.
That's right.
So looks at DNA of the sperm, pH of the sample, motility, how well the sperm are moving.
Under the microscope, yeah, he can also look at the shape of the sperm.
And all of these things can affect the chance that a sperm is going to sneak its way into, you know, through the cervix and ultimately make a baby.
And so if you avoid jerking off for a few days or even a few weeks, what happens to all these things?
All right, let's start with sperm count and volume.
Studies over and over again have found that less fapping on average means more sperm when you do cum.
And that's basically it.
It's like the semen is collecting in there, pipes are fuller.
One small study calculated that for every day the men held on and didn't ejaculate, their sperm volume increased by around 12%.
Yeah, now that huge bump, it doesn't last forever.
After four days of not fapping, the benefits get smaller and smaller.
But still, no fappers are absolutely onto something here.
But when it comes to the egg and sperm race, quantity is not the only game in town.
Quality too, right?
What's the point in having a bunch of swimmers if they can't reach the target?
And studies have found, including one that looked at sperm samples from more than 2,000 men, that if you are looking at swimming in particular, so motility, fapping is your friend.
So people who got off more tended to pump out better swimmers.
So to give you some more details about...
what frustration looks like to a sperm.
So one way we can look at this is through DNA damage.
And so when your sperm gets a little damaged, that can make it harder for that sperm to then go on to create a baby.
Who are kind of talking about their journeys into this world and how excited they are about being able to retain their semen and how you could come along on the journey too.
And so let's look at what Brent found.
So what did you find in terms of does retaining your semen improve your sperm's DNA?
Yeah, so the more time between busting a nut, on average, more DNA damage in the sperms.
And this makes sense once you have a better idea of where sperm gets stored and made in the body.
So basically sperm are made in the testicles and they're really happy there.
The temperature's great.
They got this blood testes barrier.
So here's Justin again.
And so it protects the sperm from a whole bunch of things like inflammation.
So they love it in there, love it in the testicles, but eventually the body's like, you've got to move on.
And the spermies get pushed along to this wiggly, tightly coiled tube, which is called the epididymis.
It's like high school, like a little high school for sperm.
It's a bit stressful.
And when they're in the epididymis, they can get exposed to things like oxidative stress, other things that can damage DNA.
But yeah, if you ejaculate more often, you're not hanging out in that place for longer.
And then so I guess my question was, what is the optimum time to wait then?
And if you're trying to make a baby the old-fashioned way, like through sex rather than IVF, you need to balance quality and quantity.
Because if you are jerking off too many times, the quantity will go down.
And you still need numbers.
So Brent, the fertility specialist in Minneapolis, told me like basically as you're heading into that fertile window with your partner, they're about to ovulate.
Try not to have ejaculated for, he says, two to five days.
But for some folks, they have a lot of DNA damage in their sperm, which you can check by doing a test.
And for those people, he actually recommends just one day.
Clearing the pipes faster.
But as for this idea that, you know, you want to be waiting weeks or months or, you know, doing No Nut November, Brent's like...
Once you're in the window, he says, go for it.
He says, if you've got the question of once you're in the window, do I have sex or not?
He's like, have sex.
But he also said that by the time people are seeing him in the clinic, it's so stressful.
There's nothing fun about sex at that point.
And he is saying to someone, you just have sex, whatever, can also be very stressful.
All right, our last question for the day, I asked Justin.
So then are there any risks to semen retention?
I guess if you are not in the baby-making world, is it bad if you feel good about not ejaculating?
Yes, because online you do see some quite hysteric headlines about the dangers of not ejaculating.
And the one thing that people do point to, there's sort of one bit of science evidence for this, is around prostate cancer.
Have you heard this?
There is some research suggesting that folks who ejaculate a lot have a lower risk of prostate cancer than those who ejaculate a little.
But we're not really sure what's going on here.
Prostate's big job is to help make semen.
And so possibly by clearing out the pipes, you are clearing out potentially harmful things that could build up in there.
It's not a crazy idea.
But both Brent and Justin aren't sure if the ejaculating is actually helping you to avoid prostate cancer or perhaps if something else might be going on here.
Much like masturbation, it's a bit messy.
So Justin actually told me that, you know, his bigger concern for people when he's thinking about the risks is that if you are really into not fapping and you join these communities that then tell you jerking off is bad and terrible for you, that that is going to cause harm in itself.
Oh, right, right.
Yeah, and if you buy into this stuff online that it is so bad to ejaculate, you can start to feel crappy about yourself when you start to feel horny or when you relapse even using sort of language like that.
And in fact, a study found that people who hang out more on the NoFap Reddit forums tend to feel more shame, more worthlessness.
Some even have suicidal thoughts after ejaculating.
Which is different to, because there's a lot of support groups out there for if you have cancer or various diseases and studies tend to find the more time on these forums, the better people feel because they're sort of communing with each other.
They're sharing how difficult it is.
So it's quite telling that in this case, it's kind of going the opposite.
Yeah, Justin says that totally makes sense.
You know, at worst, I did not know this before.
I thought no fapping was all about...
sex and fapping.
But away from the culture of nofap, if you are interested in going for a month or maybe even more without ejaculating, Brent and Justin were very aligned on this.
Do you want me to keep saying ejaculate a couple more times?
How do you feel about your relationship with fapping at this point?
Do you think you're going to try No Nut November after this?
Is this a challenge that after hearing the science you want to rise to?
Probably not.
I mean, it's just... It only matters if you're going to use them.
Yeah, exactly, exactly.
And this is something that former tax accountant and current comedian and also my friend, Saren Jayamana, has been curious about for a little while now.
That is exactly right.
Thank you so much.
You're no longer curious.
Oh, I'm sorry, though.
That's Science Versus.
This episode has 71 citations in it.
So if you want to read more about anything that we talked about, you can just go to the show notes and click on our transcript and it is fully cited.
So go have fun.
There's some fun papers to read.
You can find Seren on Instagram at Seren, which is S-U-R-E-N comedy.
We are on Instagram too, science underscore VS. I'm on TikTok at Wendy Zook.
Come and say hello.
This episode was produced by me, Wendy Zuckerman, with help from Michelle Dang, Meryl Horn, Rose Rimler and Akedi Foster-Keys.
We're edited by Blythe Terrell.
Fact-checking by Erica Akiko Howard.
Mix and sound design by Bobby Lord.
Music written by Emma Munger, So Wiley, Peter Leonard, Bumi Hidaka and Bobby Lord.
A big thanks to Joseph Lavelle-Wilson and the Zuckerman family.
Science Versus is a Spotify Studios original.
Listen to us for free on Spotify or wherever you get your podcasts.
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I'm Wendy Zuckerman and I'll back to you next time.
Today on the show, we're pitting facts against fapping.
I mean, you hear people's guys saying that mentally you just feel like your best self.
And it's not just your mind, but all through your body.
People say they are feeling these benefits.
On top of all of this, some say that when you do eventually decide to jerk off, the sperm coming out of you is going to be like out of control, best quality sperm you've ever produced.
And there's actually, I was sort of surprised, but do I want to call it groundbreaking science on this?
I think I do.
On the flip side, there are other people who are then saying it's actually risky to not ejaculate.
So one headline screamed, doctor issues warning against men taking part in No Nut November.
Another says, quote, shocking research shows what happens to your body if you stop masturbating forever.
So today on the show, we are going to find out, one, if you stop ejaculating for a period of time, does it bump up your testosterone, improving your mind and body, making you feel like a beast?
You were very excited about that idea.
Two, will it boost the quality of your sperm?
And three, are there any risks to holding it in?
How do you feel about being introduced as a sort of semen retention curious?
And I do want to say that some folks who practice semen retention do it to break what they call an addiction to porn or sex.
And we're not going to get into that too deeply into this episode because we've got enough to cover.
So when it comes to semen retention, there's a lot of folks saying, Girl, I became a bee.
But then there's science.
Welcome back today on the show.
Should you try to not come for maybe a month, give No Nut November a go.
I'm here with comedian and semen retention curious.
Suran Jayamana.
I just thought everyone knew No Nut November, where you don't ejaculate for November.
That's the idea.
My first question was a fairly naive one.
I asked it to Justin Dubin, a urologist and andrologist at Memorial Healthcare System in Florida.
Now, for those who are uninitiated, semen retention, I've now become very familiar with this term, but it basically means you retain your semen, you keep it in, you don't release it.
What's the FAP in no FAP?
Did you, I mean, I knew fat meant masturbation, but I didn't know it was the noise.
Yeah, neither did I. Justin, our urologist, being deep in the internet several years ago, he started noticing a lot of stuff on social media about the benefits of not ejaculating.
And so he asked his mentors.
So he does, Justin starts this study where he and his colleague basically scroll TikTok and Instagram, looking at how many people are talking about this and exactly what are they saying.
And there was just so much stuff out there that Justin said he was actually quite overwhelmed.
And by the way, they weren't just looking at semen retention.
They were also looking at other men's health topics like male infertility and erectile dysfunction.
Who's talking about it?
Yeah, Justin said it was a lot of young guys.
So, all right, so we're going to give some accurate...
When did you start getting curious about semen retention?
information about semen retention.
Starting with, can it bump up your testosterone and make you feel amazing?
And so over and over again online, you see people quoting this one study to supposedly prove this point, that if you hold on to your semen, you don't ejaculate, it'll bump up testosterone.
And here's what the study did.
I love that researchers did this study.
They got 10 men to have a wank.
to orgasm at precisely 4.30pm on the first day of the experiment.
Then the men were told to abstain from any type of sexual activity for the next 20 days.
How do you think you'd go, 20 days?
Oh, it's very much in your head.
So, okay, so on day 21...
They come into the lab.
Oh, literally.
They got to masturbate.
And throughout this experiment, like on day one, day 21, before and after the wanks, researchers are measuring their testosterone levels.
They also asked the men about their levels of sexual arousal.
And so what did they find?
After no fapping for 20 days, the men were more aroused.
They also said that once they had an orgasm in the lab...
It felt more intense and it was longer.
It was sort of like a better orgasm.
Which Justin says checks out.
On our semen retention episode.
No, but absolutely.
You have that Thai food every day.
You're not going to enjoy it.
So then the question is, of course, what was happening to the testosterone?
So generally speaking, the testosterone levels didn't change throughout the entire experiment.
The researchers wrote baseline testosterone were, quote, similar before and after abstinence.
And in fact, the only time they saw a little bit of a bump in testosterone levels was after the fellas had their big wank on day 21.
Which is odd because this is somehow being used as evidence that not fapping bumps up testosterone levels.
But to get the little boost of testosterone, you ultimately needed to wank.
So what is interesting is that other studies have shown this kind of thing too, that after you orgasm, and this is for both men and women, you do get a little bump of testosterone.
It doesn't last very long.
It's just a little bump.
But it's something that we've seen in experiment after experiment.
And in fact, the only study that I could find that suggested something a little bit fappulous, if you're not into fapping, is this small study from China that reported that after men didn't ejaculate for a week, testosterone levels went up and then went down on day eight.
But the thing is that paper's been retracted.
So it's interesting this idea persists, and I think one thing that really annoyed Justin while he was doing that sort of doom-scrolling...
on this topic is that some of the benefits that people said flowed from this apparent bump in testosterone didn't make any sense to him.
So, for example, people said that their skin looked better and their hair was thicker.
And from other research, we know that when you get a boost in testosterone, say you've just gone through male puberty.
And when there's some research to suggest that when men go on testosterone replacement therapy, for some folks, they actually start losing their hair.
With No Nut November just around the corner, we thought it was a great time to ask, what are the benefits of saving your seed and not ejaculating?
And so bottom line, when he looks at the research that we have on testosterone and even tries to think of a mechanism, that's the other thing of like, how would...
not ejaculating boost testosterone levels, like what could possibly be happening in the body to bump that up, he starts shooting blanks.
So far, we've just looked at testosterone, but there's other things that could be going on during ejaculating that could explain some of the... The other stuff.
The other stuff, the other exciting stuff that people are talking about.
That might actually help their case a little more.
Is ejaculating leaking energy?
So the next thing I wanted to look at is whether not ejaculating could improve your mood and energy and maybe even boost your athletic performance, which is something that a lot of athletes think about.
Have you heard of this idea?
I mean, in the 1998 World Cup, the English coach forbade his players from having sex.
That's so funny.
You remember that, right?
Muhammad Ali was also into it.
He built a whole farm.
So that he could be away from his wife before a fight.
So could it be true?
And the thing is, when you orgasm, it can lead to a rush of hormones like oxytocin and prolactin, which can make us feel relaxed and lower our energy.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
So if on a full moon people slept more or less...
And so now he's sure it's not the brightness of the moon anymore.
This episode about the full moon has been one of our most requested episodes this past year.
Was it just that they were partying more?
You mean like going to like full moon parties?
Would you want to see the wave pattern?
Yeah, there's a very nice wave pattern there.
It is a beautiful sinusoidal pattern.
Meryl has promised to tell us why the lunar cycles might be getting into our body and somehow affecting our sleep.
And perhaps the creepiest thing of all, people said that the full moon could make blood come out of your vagina.
What's going on here, Meryl?
And is there any evidence for that?
I mean, they didn't put it quite like that.
And so how are they detecting those changes?
Is it just, you know, through the water or gravitational changes directly from the moon?
Okay, so it's probably not gravity.
Sounds like something I should have invested in 10 years ago.
And do humans have cryptochrome?
Show me the whoa graph.
Is it the sinusoidal again?
Because I don't know if I can handle that, Meryl.
I don't know if I can handle it.
If you didn't think you were listening to a nerdy podcast, you do now.
That is, okay, so what is, is this magnetic fields?
So could the moon be affecting our body and our behaviour in these strange ways?
It's hand-drawn, that's for sure.
Like someone used a ruler to make those lines.
Okay, so what this shows us is that the moon affects the magnetic field in this sinusoidal pattern...
that is similar to the way that the moon seems to affect our sleep.
But then step two, has anyone figured out if the cryptochrome in us is actually detecting those changes to the magnetic field and that that is then affecting our sleep?
While this idea might sound like it belongs in the world of horoscopes, perhaps even fairy tales, some scientists have been taking it very seriously.
Okay, so here is where we are at.
The cycles of the moon do seem to affect our sleep.
Somehow, we're not sure how.
blood coming out of our vaginas.
And in the past few years in particular, there's been a slew of peer-reviewed scientific papers coming out and claiming that the moon really can affect our bodies.
Describing a period-based study as a wild study is immediately making me think of just a scientist throwing around dirty tampons for some reason.
Do you know, Meryl, I'm the exact opposite, that I will ovulate around a full moon.
And get my period, I guess, in a new moon.
But I just assumed it was because I'm a pretty regular cycle.
And that's just what a month is, you know, around 28 days or whatever.
in very surprising ways.
Yeah, why are our cycles the same as the cycles of the moon?
You asked for it, so here it is.
So in today's episode, we are going to look at this cutting-edge science.
And by the end of the ep, you might just be feeling a little carnal yourself.
So what did she find?
For hundreds of years, we've blamed all sorts of stuff on the... That damn moon.
But then, there's science.
That classic thing where you study something in a few people, get a very exciting result, and then you study it in more and more people and realize it's not generalizable.
We've seen this countless times before.
Charlotte and I are the anecdote in the room that gets the headlines.
Science vs. the Full Moon is coming up after the break.
You know, because obviously we couldn't... Because it's so rare?
Yeah, we couldn't all be witches, you know.
But I guess we're all a bit witchy because the moon is affecting all of our sleep in this mysterious way.
I really love the moon.
I love a big full moon.
I like looking at it.
I like thinking how small I am in this big universe.
It reminds me of that.
I love when you see it rising and it's just huge.
I love it for all those reasons.
I don't know if it's having some deeper subconscious effect on my body.
What about you, Meryl?
You've been researching this for a while.
Has it changed your view of the moon?
Do you want to yip with me?
Today on the show, we're looking at the full moon.
If you want to tell us what you thought of this episode, we'd love to hear from you.
We are at science underscore BS on Instagram.
I'm at TikTok at Wendy Zook.
Have a happy full moon.
There's one coming up on Monday.
And so we're asking...
Can it really influence us, change our behavior?
And fellow lunar explorer Meryl Horne is here.
Okay, so first up, can we just get a bit of a lay of the land?
And could you just explain why do you see a full moon or a half moon or whatever?
And to start our journey, we sent senior producer Meryl Horne out to brave the streets of New York City.
It's the meat sandwich.
Okay, so could it, could just that fact that the billiard balls up in space are in this arrangement affect our behavior?
There's a chill in the air.
Out in the east, the full moon was on the rise.
And she ventured into a park to hear firsthand what people experience when there's a full moon.
The episode is called Full Moon, not New Moon.
Now we're cooking with the rhesus monkeys.
We're in primate land.
All right, but what about human animals?
Meryl, are we affected by the food?
Why don't we start with the idea that
on a full moon, hospitals get packed, patients are going wild.
So what does expert Wendy say?
This is the show that pits facts against the full moon.
Tell us the story of Wendy's study.
Some people said that the full moon stirred up all this drama in their lives.
Well, everything inside of me wanted to go, oh, and then I realized that's no longer factually acceptable.
So Wendy, all her superiors believe this to be true.
One guy said that sometimes he doesn't even go out when there's a full moon.
I'm going to stay in that night.
I'm going to play it safe.
Just like because I know I could feel weird or do crazy stuff.
Less, less severe traumas, she said.
Folks said you just knew it was going to be a full moon that night because people at work would be going bonkers.
So, Wendy, does she worry when there's a full moon these days?
Do you know, I feel like this will really land the point.
Hashtag not all Wendy's, you know?
And this is in the research too.
It shows that some healthcare workers think the full moon makes their patients behave stranger.
If only we could all be united by the full moon.
So where do we go to here?
Does it change who we are?
One survey even showed that some doctors and nurses think they should get full moon hazard pay.
Meryl Hawn never thought I'd see the day.
Well, I think if he keeps doing research on it, he'll know that that's a myth, Meryl.
Meryl heard about this as well at the park.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
Yes, because we know from many years at Science Versus is people don't remember random information as well as they remember anecdotes and stories.
And it is so scary, this idea of losing our memory.
Okay, well, this has been a very optimistic first half.
I guess it would still be great to just have a better memory in general.
So are there bigger things we can be doing here?
And if you like what we're doing here at Science Versus, please tell your friends about us.
Some of our colleagues had seen it happen to people they love, like their grandparents, and it was really hard to watch.
Welcome back today on the show, how we can boost our memory.
Another person we talked to, Connor, he's the guy that keeps losing his keys, he was worried that he wouldn't be able to hold on to important memories in his life.
Interesting that it works at all because turmeric has been on the superfood list for years now.
And I have always wondered if it was all garbage.
But there is a little bit of evidence behind it.
Okay, so, you know, you want to put a little turmeric on your dinner, go for it.
Does stuff like crossword puzzles work?
I mean, a lot of people think crosswords help with memory, right?
Their memory was already better and so they kept doing it versus someone like me who I get very frustrated because I'm terrible at crossword puzzles and so I don't do them.
We don't know if the crossword was causing the improvement.
So bottom line, Merrilee, you're going to be doing more crossword puzzles?
It's even less sexy than a crossword puzzle.
cool I guess in its own way we're talking about sleep I just like I just like couldn't imagine anything less sexy than a crossword puzzle and then you're like let's talk about something a little less sexy than crossword puzzles I was like what a long division like I want to um is sleep sexier than a crossword puzzle am I wrong about this
I think sleep is sexier than a crossword puzzle.
And so with the stakes being so high here, it's not surprising that online you'll hear people claiming to have the solution, telling you that you've got to train your brain with puzzles or giving you some secret pill or hack to save your memory.
Did the people who had slept remember more four years later?
And do we know why sleep is so important for memory?
We can see in the rats the do-do-do-do, do-do-do-do, do-do-do.
Okay, so before the break, you promised us a thing to boost all of our memories, and that is sleep.
And shoving more things in your brain, but actually letting it have that downtime.
And the folks that we were talking to just wanted to know, is this stuff for real or not?
Also, exercise helps you sleep, so it all comes back around.
A bunch of the things that we do day to day and maybe think it's a sign that we're losing our mind and our memories are actually totally normal.
Things like leaving a room, walking into another one and forgetting why you were there.
forgetting where you put your keys.
This is just part of how memory works.
But if you are still worried about your memory and you'd like to improve it, one of the best things you could do is to get more sleep.
And barring that, give your brain a bit of downtime.
I mean, bottom line, they had one big question for us.
Can you tell me what I should do to have a better memory?
Well, that's just lovely advice in general, right?
So today on the show, what actually works, if anything, to improve your memory?
When you're having a beautiful moment, just focus on it.
So how many citations are in this week's episode?
And if people want to find them and read more about memory, science of memory, where should they go?
And if people want to let us know what they thought of the episode, you can find us on science underscore VS. I am on TikTok at Wendy Zook.
Is there anything you can do to keep it sharp as we all get older?
Because when it comes to our keys or wallets, a lot of us have been wondering... Where is that?
This is the show that pits facts against science.
Science vs. Memory will be back just after the break.
And with me is senior producer Beryl Horn.
Yeah, no, that stuff has definitely happened to me as well.
I'll go to do something and go, oh, oh.
So how worried should we be about our memories, Meryl?
So I got the end of my sentence just there.
Today, we are pitting facts against memory.
So we're back with a bunch of brand new episodes.
Because a lot of us think that our memory has gone down the toilet.
There's a scientific explanation as to why we keep losing our keys?
Senior producer Meryl Horne got to chatting with some of our colleagues at Spotify about this.
You put them in your coat pocket, winter coat pocket, jeans pocket.
And then when you've got to go through that boom, boom, boom, boom, boom, boom, boom, boom, your memory is just like throwing out all of these ideas.
It's so relatable, particularly the chocolate.
When you leave a room or leave your house or when you leave a scene, you can almost see the camera in your mind moving.
And people were really noticing this in their day to day at home.
Clicking to take a photo to create a memory.
And so to tie this back into why when you leave one room and go into the kitchen, you totally forget what you were doing.
That's because you like a memory ended and now you're in the middle of a new memory and it's hard to get back.
I guess something that really annoys me about my memory is that I can't learn Spanish faster.
And words that I knew in Spanish then are lost to me, and I wish I could hold on to them.
Oh, sorry to anyone who speaks any language.
We're recording a Science Vestas episode.
How do you say that's so funny in Spanish?
I said divertido or something like that.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
But then Karen told me about something that really changed the way that I thought about this study.
So cutting down on screens was a big part of the study.
And it's not just in the US.
In Japan, Canada, Australia, Europe, rates of autism have been going up too.
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?
I have a very satisfying study for you now because Karen told me about a study where they basically did that.
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.
And now there is this huge fight brewing as to what's behind this.
But they didn't tell them anything to do with screens.
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 like there are also other explanations why we might see a link between screen time and autism.
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 like 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.
Why do so many people have autism these days?
Maybe they're more likely to end up with an autism diagnosis because their social skills aren't getting like a workout.
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.
Okay, so here's where we're at.
I feel like we have not gotten that lion's share of these cases yet.
I mean, there's more meerkat dinners here and there.
But we're missing something big still.
Yeah, that's what we're going to look at after the break.
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 it plays 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.
I feel like we've earned it.
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.
And, you know, 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.
So to get to the bottom of this, I decided to call up a scientist who has been diagnosing autism for decades.
This is Katherine Lord, professor at UCLA.
Did you ask her if she was stupid?
my first question.
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.
There's all these different theories about what's causing this, from vaccines to pollution and a whole bunch of other stuff.
She's also the diagnostic queen because she's been in this field through the like 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 snooze fest, but it's, you know, it's actually the story of like how our understanding of what autism is has evolved.
So that means if you have an idea, something that you want us to versus, you've got to tell us.
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.
And this is kind of what we thought autism looked like then.
This is when Catherine got into the field as an undergrad, and she loved working with autistic kids and finding ways to connect with them, even, you know, 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.
Like, Catherine remembers this one kid.
So wait, what made him...
What else about him made it clear that he had autism?
Well, now we know that, like, it's not necessarily that you don't have any language at all, but, you know, the way he used language was really different.
Like, he would often repeat phrases over and over again.
And so, yeah, it's, like, 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, right?
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, like, 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.
But then there are folks saying, whoa, whoa, whoa, whoa.
So this is, I mean, the late 80s is exactly when Rain Man came out.
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.
There's actually a much simpler explanation here.
You know, he was a character that was a genius in some respects.
I mean, like he could memorise the phone book, right?
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 it all has to do with how we diagnose autism in the first place.
And also kind of going along with this, we used to think that Asperger's syndrome was something different.
And now that's been rolled right up into autism spectrum disorder.
It's all part of the same thing.
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, you know, 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.
What is going on here?
We're now opening up the definition to include folks who are neurodivergent in more subtle ways.
At a recent press conference, RFK Jr.
But that would mean you should be able to see that in the data, right?
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.
He painted this really dark picture where he called this a tragedy and said that, quote, autism destroys families.
said that we're going to start to have answers on the root cause of this epidemic by the end of the year.
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?
A couple researchers told me, like, oh, you have to talk to Maureen Durkin because you just presented this work at this huge autism conference that looks at that exact question.
So, yeah, she's an epidemiologist at the University of Wisconsin-Madison.
Can you hear me okay?
Hi, I can hear you great.
So Maureen 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.
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.
But Christmas has come early because today on the show, we are going to find out what's happening.
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.
And so, actually, let's start there and find out, like, what Maureen saw when she looked at those kids over time.
This group... Did not increase at all.
In fact, it declined a slight bit.
But it didn't increase.
And when she looked at what cases were going up, it was a totally different group of kids.
Yeah, so these are kids who are autistic who don't actually need any more help than neurotypical kids in their day-to-day life.
When it comes to the rise in autism, there's a lot of fingers pointing at lots of different things.
And then Maureen also saw a rise in kids who maybe need a little bit more help.
And this research isn't out in a journal yet.
It's in 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.
So this is looking over time from 2000 to 2016.
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.
It's really these milder forms.
That's what's, that's the lion's share, Meryl.
So I asked Maureen.
And so these were the cases that we were kind of missing decades ago.
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 Katherine Lord 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?
But then there's science.
So in a press conference recently, Health and Human Services Secretary Robert F. Kennedy Jr.
basically kind of pooh-poohed this idea that it is just about changing diagnosis.
Science vs Autism is coming up just after the break.
So is he wrong, basically?
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.
And that leads me to the final thing I wanted to mention, because 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 was a strong bias towards diagnosing boys with autism.
So this is Dina 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
There's a lot of ways to do it.
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, you know, these people weren't getting any diagnosis at all.
In a lot of cases, they were getting misdiagnosed with something else.
This happened to Dina.
So for Dina, even though she never had bipolar, she was put on lithium.
What did the lithium feel like?
Researchers have told me that this is actually kind of a common thing that, you know, 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.
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.
Today we're looking at autism and finding out why the numbers of people being diagnosed with it have been going up and up.
But, you know, like, it's funny, we keep using that word epidemic to describe what's going on, and I don't think that's actually the right word to describe, like, the rising cases.
I mean, lots of scientists have told me that, like, 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 Dina about that.
How do you feel about the fact that we're seeing more and more people being diagnosed with autism today?
You can do it on social media, Instagram, TikTok.
Yeah, so for Dina, it was like the start of really understanding who she was and also helped her find a community of other autistic people and also other moms of autistic kids since her son is autistic too.
To tell us all about it, we have senior producer Meryl Horne.
Well, we've solved the case of the so-called autism epidemic.
All right, Meryl, can you just tell me what exactly is autism?
That's science versus.
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 citations chat.
And a baby's here too.
How many citations are in this week's episode?
Sixty-eight citations.
Katie, what was your favorite moment of the season?
I just feel like people kind of throw it around, diagnosing their friends with it, their friends' children with it.
It's my new vocal stem.
I say it at least like a couple times a week for sure.
I just have to pick the fact that we finally made our episode on squirting.
It was just a delight and it was a long time coming.
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.
Ways to get in touch to pitch us ideas are all in the show notes.
The citations link to the transcript.
It's also in the show notes.
But to cap us off, all right, everyone, let's say primal.
Is there a better word?
Is there a better science word?
Peer-reviewed literature.
Thank you so much for listening, and we will see, and you will hear us very, very soon.
You know what I mean?
This episode was produced by Meryl Horn, with help from me, Wendy Zuckerman, Katie Foster-Keys, Michelle Dang and Rose Rimler.
We're edited by Blythe Terrell.
Fact-checking, research assistance and consulting by Erica Akiko Howard.
What are we talking about here?
Mix and sound design by Bobby Lord.
Music written by Emma Munger, So Wiley, Peter Leonard, Bumi Hidaka and Bobby Lord.
A special thanks to the researchers that we reached out to, including Professor Karen Pearce, Professor David Mandel, Professor Deborah Bilder, Professor Frédéric Bonnet-Briol, Dr. Helen Tager-Flussberg, Dr. Isabella Della Lara, Catherine Byrne, Professor Sven Bolte, and Dr. Whitney Worsham.
Well, it can show up for different people in different ways.
Special thanks also to Lynn Keys and Bella Veseca, Chris Suter, Elise and Dylan, Jack Weinstein and Hunter, Joseph Lavelle-Wilson and the Zuckerman family.
Science Versus is a Spotify Studios original.
But generally, a lot of autistic people will have a harder time communicating.
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.
So that's a big theme.
There's an email address.
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 a thing.
It's all in the show notes.
And then our big question of this episode is why do so many more people have it these days?
So if you've got an idea, something that we have to versus, please let us know.
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.
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 if 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.
We absolutely love hearing from you.
And so based on all that, scientists have kind of figured out how much of autism is inherited.
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.
Now, on with the show.
Other times it'll just be like one particular kind of genetic quirk.
But yeah, genetics is huge.
Today's episode is all about autism.
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's 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.
Because we're asking, why do so many folks have it these days?
Okay, so overall in the U.S., about 3.2% of kids are autistic.
So that's kind of like the baseline chance on average.
Yeah, so one in 31 kids.
Yeah, it works out to 3.2%.
But if you're a mom over 40, we think that the chance goes up from 3.2% to something like 5.6%.
That's not nothing.
And then what about...
What about the other side of this, the sperm?
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?
Rates of autism have been going up and up for decades.
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% 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 not going to explain the lion's share.
So what else could explain the lion's share?
But then a couple of months ago, the CDC released the latest numbers, catapulting this issue into the spotlight.
We've got like the meerkat's share covered.
Lion's share still out the open.
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.
This is our last episode for a little bit.
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.
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, 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...
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.
was talking about why autism is so pervasive, he said, quote, this is coming from an environmental toxin.
What do you make of that?
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 environment 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 neuroinflammation.
But the kind of pollution that's linked to autism has generally been going down over the last couple decades in the U.S.
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.
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.
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.
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?
And what do they find?
A few studies say yes, but the vast majority of them find no connection.
Okay, there's no smoking gun here thus far for the lion's share 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 done
People blame everything on screens.
And I was just like, I don't really buy it.
We're going to take a short break until September while we work on new episodes.
But then like, let me tell you what happened, though, when I talked about it with this researcher.
And the rates in boys were even higher.
And unlike me, Karen was like, well, it actually makes total sense to look into screens, particularly when you look at the timeline here.
But it's not just that the timing fits here.
Health and Human Services Secretary Robert F. Kennedy Jr.
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.
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.
says this is an epidemic.
It was really, really tiny, so they only had nine families.
But I thought it was interesting because the...
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.
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.
And so she looked to see if this had an effect, and it seemed like it did work, like the kids had a decrease in some autism-related behaviors by the end of the study.
specifically in social skills and repetitive behaviors.
That feels promising.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
Is that true?
Does the carnivore diet protect you from diabetes and getting heart attacks?
That's cool.
But that's just part of what this diet is about, right?
You cut out the carbs, but what about eating all that meat?
I mean, what happens to your heart disease risk?
when you eat all that meat?
OK, so here's where we're at.
These risks that people are concerned about with the diet around vitamin deficiency and heart disease and cancer, it's not as if these risks are total garbage and this diet is 100% safe.
In fact, researchers did a big survey of people who have been on the carnivore diet for at least six months, asking them about their mood, hunger levels, weight and health.
There still could be risks here, we're just not entirely sure, which means that the benefits...
It's all about how good the benefits are.
Yeah, to outweigh these unknowns.
So, after the break, the benefits.
Welcome back.
Welcome back.
Rose Rimla, people say they feel amazing on this diet.
Tell me about it.
I want to hear the good stuff.
And tons of people reported that they loved this diet and it improved their health.
But to a lot of us listening to this right now, the carnivore diet feels plain wrong.
So how is this diet helping them?
There's the environment to think about.
Plus, we've been told our whole lives that eating vegetables is good, and eating loads of meat puts us on a fast track to crappy health, stuff like heart disease and cancer.
What's the thinking here that these bowel conditions are caused by an array of different things potentially?
And if you...
Personally, maybe you are a little sensitive to some of the stuff in vegetables and then cutting them out of your diet actually might help.
But on the other hand, you might be someone who's sensitive to the stuff in meat and then a vegan diet is going to help you out.
But I guess if you are really suffering and have tried a bunch of things, heck, maybe give it a go, I guess, with the risks that we talked about at the beginning of the show in mind.
Which is where your brain and your body starts using this chemical called ketones for energy rather than using sugars, which is what it mostly runs on.
And so that's very helpful news that if you are going all the way on the carnivore diet, you can have some vegetables and probably still stay in ketosis.
So who's right here?
That makes sense.
And then as far as why you might lose weight on this diet.
Can a carnivore diet really make you mean and lean?
You know what?
Let me guess, Rose.
Or is this diet a big mistake?
So we've talked about people with specific conditions giving this a go, but I guess for the rest of us who are just trying to live our best, healthiest lives, do you think the carnivore diet is a good idea?
Fancy eating meat?
Because when it comes to the carnivore diet, it makes a lot of people feel... But then there's science.
Yeah, and those studies are huge, right?
There you go.
The risks to the environment are known.
Science versus the carnivore diet is coming up just after the break.
This episode was produced by Rose Rimler with help from me, Wendy Zuckerman, Akedi Foster-Keys, Michelle Dang and Meryl Horn.
A lot of meat?
We're edited by Blythe Terrell.
Fact-checking by Erica Akiko Howard.
Mix and sound design by Bobby Lord.
Music written by Emma Munger, So Wiley, Peter Leonard, Bumi Hidaka and Bobby Lord.
A special thanks to the researchers we reached out to, including Dr. Lawrence David, Dr. Andrea Korachick, and others.
Science Versus is a Spotify Studios original.
Listen to us for free on Spotify or wherever you get your podcasts.
And wherever you do listen to us, give us a five-star review if you like what we're doing.
It helps others find the show.
But if you are listening on Spotify, then to follow us, tap the bell icon so you get notifications when new episodes come out.
I am Wendy Zuckerman, and I'll fact you next time.
Welcome back.
Today on the show, meat, meat, meat, meat.
I'm here with senior producer, meat head, Rose Rimler.
So on this diet, people just eat meat, right?
You can't eat any vegetables.
Yeah, because when it comes to this diet, I have seen people proudly taking photos of a plate of food.
That's like two steaks, two eggs, a sausage on the side.
And then just for garnish, three blueberries.
And they're like, carnivore diet.
And all the comments will say, get that blueberry off your plate.
Because that's how T-Rex ate her food, right?
That's my question.
Are these people okay?
That's why your gums can bleed?
That's all I know about scurvy.
Some say this diet is so good because it's... Others say it's the best thing they've ever done for their health.
They feel more vital, their brain seems to work better, and their chronic illnesses seem to have disappeared.
What was going on?
One big influencer here is Michaela Peterson.
She's the daughter of the controversial author Jordan Peterson.
This is the show that pits facts against flesh.
And Michaela says that the carnivore diet cured her rheumatoid arthritis.
And so no deficiencies?
No vitamin deficiencies?
Here she is giving a talk about it.
It is interesting.
Oh, that's cool.
So you think people on the carnivore diet, maybe they won't get these deficiencies?
Yes, that's right.
You start veering towards the little kangaroo poos.
But it's not just about poo because fiber is very important for a bunch of other things.
It can lower your risk of heart disease, lower your risk of colorectal cancer.
Her dad went on the diet too.
Here he is telling Joe Rogan about it a couple of months ago.
Today on the show, the carnivore diet.
This diet is blowing up right now.
So you're giving them oxygen artificially.
What would it be like to die like that?
That I've heard you say that you are obsessed with solving mysteries.
If some of his victims weren't unconscious, they would have felt it.
Yeah, that's right.
Because Ian, we talked about it, and he said it would be almost like drowning because you're not anesthetized necessarily.
So these drugs don't conk you out or, you know, put you to sleep.
So you just can't breathe.
And you can't even, like, move or scream.
Oh, my gosh, I can't imagine.
Awful, awful.
Now, it is worth saying that in Efren's confession, according to the cops, he said that he would only do this
to patients who are unconscious.
I don't, like, there's no way.
All 40 of them?
Yeah, I don't know how we can know that for sure, exactly.
So the cops hold Efren Saldivar on suspicion of murder.
What is it about a mystery that just grabs you and you cannot let go?
But even though he'd given this detailed confession, admitted to killing dozens of people, in the U.S.
that's not enough to go on because of this rule that's called corpus delecti.
Yeah, so tell us about it.
Body of the crime, tell us what it is.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
Yeah, and in this case, all they have is a confession.
They don't have any physical evidence because these patients really just could have died because they were sick.
Yeah, okay.
So John, the cops, hold him for a couple of days while they're doing some detective work, but in 48 hours, what's he going to come up with?
And so they have to let him go.
And when he gets out, Efren goes on national television and says that he lied about the confession.
And Sarah, our journalist, told us that Efren basically says... I didn't do it.
He sort of gave this idea that he was really depressed and basically suicidal and thought that if...
He confessed to these killings, then maybe he would be given the death penalty, and then that would be his way out.
But then he changed his mind, he says.
I guess so.
I guess so.
He also said at the time that he was taking Valium and other sedatives and barely remembered what he said to the cops.
And even a hospital spokesman around that time said, quote, "'We don't know if anything happened.'"
Yeah, but meanwhile, the medical board responsible for respiratory therapists suspends Efren's license to practice, so he's no longer working at the hospital.
And the cops, cops like John...
They're not totally buying that his confession was a lie because it was just so specific, the drugs he used, you know, exactly how he did it.
It felt like a weird thing to just say.
So the cops stay on the case and actually create a task force to find out what is going on here.
And they start going through every patient that died under Efren's watch.
And they're looking for suspicious cases.
And this is a huge task.
Well, today we have a real mystery for you and it's got a whole bunch of science in it.
It meant wading through more than 1,000 complicated medical records.
But they talk to the doctors and they learn fast.
And they're looking for patients who weren't given Pavalon or succinylcholine legitimately at the time of their death, so they didn't need it for surgery.
They start looking for patients as well who, at the time of their death, had this particular pattern in their breathing and heart rate moments before they died that might suggest they were given Pavalon or succinylcholine legitimately.
So should we jump in?
They're also on the hunt for situations like salbius sartreans and the other patients we talked about at the start of the show where they're doing better and then suddenly they die for no clear reason.
Like nosedive, yeah.
And so after months of trawling through these records, they come up with 20 people whose deaths at the hospital were highly suspicious.
And so now the plan is to exhume the bodies from a cemetery and search for the drugs that Efren had said he used to kill the patients.
Ashley, that is the question.
Because the cops start asking around and they realize that we do not have a good test to find these drugs in this situation.
Basically, you can't pull out some easy-peasy test off our forensic science shelf that would detect what's expected to be pretty low levels of pavillard or succinylcholine in a decomposing human body.
It's two days after Christmas in 1996 and a woman named Salby Esatrian is rushed to Glendale Adventist Medical Center in California.
So bottom line, even if they exhumed those bodies from those graveyards,
There's no reliable test to find these drugs inside them.
They've got nothing.
So now what?
The story can't end here, obviously.
They get a tip that there is this place that just might be able to help them.
It's a lab that some call the lab of last resort.
What a name.
It's where we're at in this story, right?
Yeah, true.
This lab is called the Lawrence Livermore National Laboratory.
It's this huge, sprawling facility in California that was created in the early days of the Cold War and does some truly bonkers stuff.
So they design nuclear warheads.
They have one of the world's most powerful lasers.
And they also have this forensic science center that can trace tiny amounts of chemicals.
What are they doing at this lab?
So they use it to find chemical weapons, evidence of chemical weapons in an environment.
And also alleged murderers.
And here's how John describes this slab.
After the break, we'll get inside that high security village, the lab of last resort.
She's 75 years old and is having trouble breathing.
Welcome back.
Today on the show, I'm here with Ashley Flowers, host of Crime Junkie, and we are cracking the case of Efren Saldivar, a healthcare worker who's suspected of killing dozens of patients.
Let's do it.
So we're now heading to the Forensic Science Center at Lawrence Livermore National Laboratory in California.
The lab of last resort.
And it's now up to some serious nerds to try to detect the tiny amounts of drugs in bodies that have been buried for years.
Armando Alcaraz is an analytical chemist who works at Lawrence Livermore.
And he was on the team who had to now create this test.
One hospital worker told the LA Times about her.
So here's what they have to do.
Let me describe the needle and the haystack.
He said, she's a sweet old lady.
So needle is the drugs.
The haystack are the loads of other chemicals that would be in these decomposing bodies.
Armando told us that some of the patients were smokers.
So tobacco would have been contaminating the tissue.
So would any embalming fluid used in the burying process.
dirty water would have been seeping into the coffins by now, leaching in all of these chemicals from the soil surrounding it.
She got treatment at the hospital.
And it meant that if you were to look in liquid in their bladder.
And on December 30th, she's breathing on her own.
You don't even know if it's like body fluid or outside fluid or... Exactly.
So they get to work and they quickly realize that one of the drugs that Efren had said he used to kill patients, succinylcholine, that is basically a lost cause.
It's just too hard to identify it in a human body after all this time.
Things are looking pretty good for her.
But then three and a half hours later, Salby was dead.
So they zoom in and try to create a test to identify Pavalon.
And because they don't want to be doing this work in human bodies, they start working with something that's pretty close to a human body.
So Armando and his colleague get pig livers and they add a tiny bit of Pavalon.
So because they would take this pig liver Pavillon milkshake...
And in some cases, let it sit and decay for months, making it more like what these bodies that have been decaying would be like.
That same day, Eleonora Schlegel goes into Glendale Adventist.
At this point, Armando and particularly his boss, Brian Andreessen, are up to their elbows in decomposing pig livers.
Word on the street is that the lab did smell kind of gross.
What did it smell like?
So decomposing bodies, whether it's pigs or humans or whatever, they emit these chemicals.
And the two that he talked about, cadaverine and putrescine, they give off that particular smell of death, that smell that you described.
She has some chronic illnesses, a nasty case of pneumonia.
And here's how Armando described it.
On New Year's Eve, her son Larry, he said in a documentary that she was sitting upright and breathing as best as she could.
So while covered with this smell of death...
They take the, we're going to go back to the decaying pig milkshakes that have been spiked with Pavalon.
And they pass them through this particular contraption that's called a solid phase extraction polymer.
It looks a bit like a plastic syringe and it has a kind of filter in it or what's called a cartridge.
And inside it, they're basically trying to separate Pavalon from all the other crap that is in these tissue samples.
But what you have to know is that there's different cartridges out there that are used to isolate different chemicals.
They apparently have this toast and say next year will be better.
I had never thought about how one would isolate chemicals from a human body.
And so basically they're pushing all tiny bits of samples through these little syringes and what the game is to find the exact right cartridge that's going to trap Pavalon
but leave out everything else or as much as possible of everything else.
And so Armando's colleague has been working on finding the right cartridge.
Armando's focusing on another piece of this puzzle.
It's really tough.
Just passing this milkshake through these filters could take days depending on how decayed the tissue is or how much mucus is in it.
May turns into June.
They're pulling 16-hour days.
It's just late night after late night.
But on January 2nd, Larry sees a message on his answering machine and it's from the hospital.
And if you're going to do true crime, you better bring in the true crime queen.
They're not finding what they need.
It's depressing.
Nothing is working.
But then one day, Brian is testing this cartridge that was designed to detect the residue of chemical weapons.
And from across the room, Armando hears his colleague saying something.
His mum had died.
They found the magic cartridge.
So Armando would now extract all the chemicals in the cartridge and then using a bunch of tools like mass spectrometry.
Oh, my God.
This is why we call it mass specs because there's so many R's in that word.
Using tools like mass spectrometry, which separates chemicals based on their weight, and then try to identify Pavalon in that sample.
And here Armando catches a break because it turns out that Pavalon creates this really unique signature that,
which meant, yes, they can identify this drug.
And so now it's time to see if what works in pig livers works in human bodies.
So in the spring of 1999, the cops start driving out to the graveyards and bodies start getting exhumed.
And they're just toasting the day before.
And John said even for him...
This pulling out bodies from the ground, this was rough.
Oh, my gosh.
So the caskets get opened, bodies removed, tissue samples are taken out and then sent to the lab of last resort.
Similar situation happens again.
Finally, after all this time, Armando and his colleagues start testing their very first patient.
You know, at this point, if they find Pavalon in these bodies, it really does mean, you know, there was no reason for Pavalon to be in their system unless Efren had put it in there.
So they start testing patients.
Jose Alfaro Sr.
He was a father.
And then they test the fourth patient.
He'd fought in World War II.
He arrives at Glendale with severe pneumonia and two days later is found dead.
They test another body.
They don't find it.
But then they get another hit and another hit.
And they tell the cops, you know, these, Pavalon, we are finding it.
And John remembers how he felt.
Yeah, so they picked out the 20 patients that were most suspicious because they couldn't exhume a thousand bodies.
And at the time, these deaths are sad, of course, but they don't raise any eyebrows because these patients, they were sick, had chronic illnesses.
So these are the suspicious cases.
I think we don't know.
They could have been killed with succinylcholine.
Or it could have been that the pavillon wasn't at too low levels to detect.
Or it could be that maybe the rest of the patients actually weren't killed by Ephraim.
We don't know.
That's the thing.
When you don't find the chemical, you just don't know what the answer is.
But finding the chemical showed that at least with six patients...
There was this drug in there.
Because that's how many patients, that's how many bodies that they found Pavalon in the end.
It was six, including Jose Alfaro, who fought in World War II, Salvia Satrian, and Eleonora Schlegel, who toasted to the New Year with her son.
And still after this test, the cops actually aren't ready to arrest Efren just yet because this was happening just a few years after the OJ Simpson trial.
And that case kind of fell on its face because the cops messed up and mishandled evidence.
So Armando and his colleagues not only test the bodies for Pavalon, but then all kinds of stuff around the bodies.
Because there was this suggestion that maybe Pavalon would be in the soil or would have been in the crypt water or the embalming fluid and then made its way into the bodies.
And so they test that stuff.
You know, it's a hospital.
Everything's looking fine.
You know, when Ian Musgrave, who was our pharmacologist, read details about their work, he said, and I have never heard an academic describe a paper like this, but he said it was like seeing an experienced figure skater.
Every move is smooth and beautiful.
I love that.
Someone can appreciate the art.
And so in January 2001, this is three years after Efron's first confession, the cops arrest him on his way to work at a construction site.
John brings him in for questioning.
He tells Efron all the evidence that they have, that Pavalon was found in six bodies.
Really close within days of each other.
And as John remembers it, Efren confesses to killing the patients.
And at first he won't say how many he killed.
And instead, he tells John what it takes to kill patients using Pavalon.
And he says with just one vial, you can kill a lot of people.
A few months later, though, rumours have been circulating that the deaths of patients like these didn't happen just because they were sick and elderly, but that these people were killed on purpose by someone who works at the hospital.
Oh, my gosh.
Your mouth fell agape when you heard these numbers.
Tell me what you're thinking.
No, he didn't remember the patients.
I mean, he even said that he like lost count at 60 patients.
Host of Crime Junkie, Ashley Flowers.
So as for the question of why he did it, John actually got, when I asked him, the cop, you know, what do people get wrong when they report this story?
And he got quite passionate and he just said, you know, this case has been reported as an angel of death case that Ephraim was trying to reduce their suffering.
But for this case, I mean, John says that they were specifically looking for victims who were getting better.
You know, like you said, who were toasting New Year's, who wanted to live.
And in that confession room, Efren told John that there was a completely different reason for doing what he did.
He told the police that, quote, it was not something that gave me joy.
And then he said, quote, only when I was only at my wits end on the staffing, I'd look at the board, who we got to get rid of.
So callous.
We talked to Sarah, our science journalist, about the victims.
The rumour is that someone is injecting something into their IV.
Efren was sentenced to six consecutive life terms without the possibility of parole for the murder counts and 15 years to life for the attempted murder of Jean Coyle, who was the woman who survived.
And there is this extra weird twist to this story, Ashley.
Because if Efren had gone to trial instead of taking a plea deal, he might have been faced with the death penalty.
Ashley, tell me what your face is doing right now.
And at that time, if he got the death penalty, do you want to guess?
They would have used the same drug.
One of the drugs that they would have used to kill him was Pavalon.
So Ashley, that's the case of how some nerds used some smooth and beautiful moves to catch a killer.
Yeah, exactly.
Well, thank you so much for joining the show, Ashley.
Thank you for having me.
If you want to know more about this case, then go check out our transcript.
So in the show notes for this episode, there's a link to our transcript and it's fully cited.
So there's links to Armando's amazing work that looks like a figure skater and also links to some amazing reporting that was done by staff at the LA Times who we used to help make this episode.
Also, Sarah Skoll's book is called Countdown, The Blinding Future of Nuclear Weapons.
And this story didn't make the cut.
So it's called Countdown, The Blinding Future of Nuclear Weapons.
This episode was produced by Katie Foster-Keys and Joel Werner, with help from me, Wendy Zuckerman, along with Meryl Horn, Rose Rimler and Michelle Dang.
We're going to get into what these rumors are, who everyone is blaming.
We're edited by Blythe Terrell.
Mix and sound design by Sam Baer.
Fact-checking by Diane Kelly.
Music written by So Wiley, Bobby Lord and Bumi Hidaka.
A special thanks to Roland Campos, Steve Wampler, Audrey Williams, the AudioChuck team, Jasmine Kingston, Connor Sampson, Stupid Old Studios, and Penny Greenhalgh.
Science Versus is a Spotify Studios original.
Listen to us for free on Spotify or wherever you get your podcasts.
And if you are listening on Spotify, follow us and tap the bell icon so you'll get notifications when new episodes come out.
Welcome to Science Versus.
Also, if you do like the show, we would love it if you would give us a five-star review because it really helps new listeners find the show.
I'm Wendy Zuckerman.
Back to you next time.
What on earth happened here and how the hell a lab that develops nuclear bombs got involved.
I'm so excited to be here.
Welcome back.
We've just found out that patients at a hospital in California are dying under perhaps suspicious circumstances.
Ashley Flowers, host of Crime Junkie, is here with us.
Hey, Ashley.
So it's now 1997.
So something that a lot of people might not know about you is that you graduated from biomedical science.
Whispers are going around that one guy might be killing these patients, and his name is Efren Saldivar.
So we talked about him with science journalist Sarah Scholes, who wrote a book about nuclear weapons and stumbled across this case.
So Sarah told us that back in Vertigo Hills High School, Efren was a bit of an oddball.
In the senior Will's section of his high school yearbook at Vertigo Hills, he wrote, I, Efren, of great mind and hunk body, hereby will three quarters of Vertigo's female population my enduring love and passion.
The right to preserve me in their hearts and souls for the rest of their lives and other times.
Eternally yours and mine, Efren.
Studded large.
That was your degree.
He was pretty nerdy.
A hunk would not be.
If I was making a film, a high school film, he would not be cast in the hunk category.
So Efren makes it through senior year, but ultimately drops out of high school.
So he's working at a grocery store.
Is he talking about scrubs?
He liked the scrubs, which might sound like a weird reason to go into the healthcare profession, but you know, you're 18, cute fit.
I think the person who came in also had a stethoscope, so that might be kind of cool as well.
So Efren enrolls in a respiratory therapy program, and respiratory therapists help patients who have trouble breathing.
So they give patients drugs, oxygen, and manage ventilators, stuff like that.
And so when Efren is just 19 years old, in 1989, he gets a job at Glendale Adventist Medical Center.
I see where this is going.
This is the place where the patients at the start of the episode died.
So at Glendale Adventist, part of Efren's job was to take care of really sick elderly patients.
And Efren is put on the graveyard shift.
So he starts moonlighting and working at other jobs too during the day, other hospitals.
So Efren is working all these jobs.
He's a bit overwhelmed.
And at one point, he starts gaining some notoriety at the hospital.
So here's Sarah, our journalist again.
Magic feels like a really weird word to describe it.
And this is where, from reporting about this hospital at the time, it seemed like the healthcare workers, particularly the respiratory therapists, had this really, you could call it a dark sense of humor thing.
And then sort of other things start happening that make it harder to pass off as a joke.
So here's Sarah.
A co-worker also says he sees an empty syringe and a bunch of drugs in Efren's locker.
Drugs like morphine and this medication called succinylcholine, which is going to become important later.
And so in April of 1997, a co-worker ends up reporting Efren to a supervisor.
Today on the show, how a lab that designs nuclear weapons helped catch a serial killer.
So they didn't find anything unusual here.
They let it go.
Efren keeps working.
And it's not until almost a year later, in February 1998, that the hospital receives another tip.
The guy on the phone ends up being a pretty dodgy guy with a criminal record and seems to be implying that if he gets an extra $50,000, he'll give more information.
He's basically extorting the hospital.
And so this time the hospital calls in the Glendale Police Department and
And by the way, we did reach out to the hospital to ask them about parts of this story.
Yes, all questions should be directed at Glendale Police Department.
So enter Detective Sergeant John McKillop from the Glendale Police Department.
He is put onto this case and John and his team start poking around and John told us that he is actually not buying this idea that Efren is a killer.
What was so odd about it?
How are you feeling at this point, Ash?
What's your spidey senses telling you?
So, but still, to sort everything out, on March 11th, 1998, John's partner, Detective William Curry, calls Efren into the station just to ask him some questions.
But John actually had something else to do that day.
You take care of this.
But it turns out this was not silly.
When the cops start questioning Efren, he confesses to killing dozens of patients.
Pretty quickly, he says he killed 40 to 50 people.
Over, like, what span of time?
It's pretty vague at this point.
The cops just found it very strange, particularly given this attitude of, I'm going to go play hockey, sure, bring him in.
They want him to do a polygraph.
The way that the cops remember it is just all of a sudden he starts talking and they were in the room going, oh, someone get a pen, write this down.
Exactly, exactly.
And so John is playing hockey.
So not only did he say that he killed patients, but he also told the cops how he did it.
Like sometimes he would kill them with these drugs.
He said he either used a drug called Pavalon or one called succinylcholine.
Which is what they found in his locker.
Does he say why?
At the time, he said that he did it to ease the suffering of these patients.
It doesn't really make sense.
He sort of fashions himself as a little bit of an angel of death type character in that room that he didn't like seeing the patients suffering, says things like that.
I think that's one of the reasons I love science too.
So we wanted to know a little bit more about what these drugs do in the body and why they're used by healthcare workers.
So we talked about this with Dr. Ian Musgrave, and he's a molecular pharmacologist at the University of Adelaide in Australia.
He told us that pavilon and succinylcholine, they interfere with how a particular neurotransmitter works in our body, and ultimately they can paralyze your muscles.
It's a way to understand the world.
That is, if you don't want to kill someone, why are we using these drugs in hospitals?
If science is your side piece, I guess, your true love is really mysteries.
And, well, these drugs are sometimes given to patients before surgery and it helps doctors to intubate them, you know, put the tube down their throats.
It can stop you from gagging.
Or if you wake up during, let's say, surgery, it would keep you from moving around so a scalpel doesn't slip.
But because these drugs paralyze the muscles that allow you to breathe, if you're using them in a medical setting, you have to give someone a breathing tube or a respirator.
That's a nerdy way of saying she couldn't find a smell.
We actually choose mates that are less compatible when we're on hormonal birth control.
No, there's no ovulation scent.
Ode ovulation is not a thing.
On top of that, Medida got guys to come into the lab as well and sniff bio samples from the armpits of the women throughout their cycle.
To see if the men's noses were more sensitive than her very sensitive chemical analysis.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
I guess so, yeah.
And they couldn't tell.
They didn't find the ovulation sweat any more attractive.
So based on this idea that, you know, people blame the pill for...
Today, we are tackling the pill.
The fact that our scent does not change over our menstrual cycle suggests to me it's garbage.
Like the pill doesn't change your scent and therefore wouldn't make men more or less attracted to you because of that.
Yeah, I think that's right.
I agree with that.
And so just to take it back to something we heard at the start of the show, I asked Julia about that Elon Musk line saying, like, this is true.
If you take the pill, you end up with the wrong person.
And he said it will, quote, make you go out with people you don't actually like.
So what is your response to that?
No one has ever provided any compelling evidence that this really happens.
We're hearing the pill can tank your mental health.
Even going back to that study that found that people who used hormonal birth control had 50% higher odds of getting divorced.
Well, the same study found that you had 60% higher odds of getting divorced if you'd ever used condoms.
Oh, so just using contraception makes it more likely you'll get a divorce?
Something else is going on there.
Yeah, I think what we could say from that study is like whatever is driving people to divorce, it's not hormones, you know, in their contraception.
I was the most depressed I've ever been.
Yeah, yeah.
So, Wendy, we've had ourselves a real nice little debunk fest.
But the pill is not totally innocent.
So let's look at some of the stuff that does seem to happen.
And let's start with libido.
Because another potential consequence of not ovulating is that you could be less horny.
I didn't feel like me.
Yes, right.
And we know, based on science, real, actual science, that when you're ovulating, on average, you do get a little more horny, right?
Which makes sense.
And so, you know, if you take that away, maybe that could tank your sex drive.
And so to figure this out, there were researchers in Sweden that enrolled almost 350 women into a study and gave them either birth control pills or a placebo.
That sounds dangerous.
They were told to use condoms or some other backup.
So they didn't know if they were on the pill or not.
And they got the survey about their sexual function, essentially, before they went on the pill and after they went on the pill or placebo.
And it turned out that on average, people's sexual desire, arousal, and pleasure went down over the course of the study, so over three months.
And this is a weird way to think about something like desire, but the amount of the decrease was like 7% or 8% of a decrease.
So it's not necessarily going to tank your sex drive, but still, I mean, that is something to think about because this was an average ride, so it would have affected some folks more than others.
Yeah, for sure.
And we don't know exactly why this happens.
It could be the ovulating thing, but also bigger picture.
There is this sort of package of mental health effects that a lot of people say they experience when they take the pill.
They say that the pill has actually been harmful to their mental health.
And the same research actually gives us some clues about that because these women were also given surveys about their mood.
So what did they find?
So these women also scored worse on stuff like feelings of well-being, vitality, and self-control, interestingly.
Folks are even worried that the pill will mess with your brain.
And other studies that track people who take the pill do find an increase in depression.
And in clinical trials, 4 to 10 percent of people who went on the pill developed symptoms of depression.
And what do we know about the mechanism here?
Because on TikTok videos, you see people sort of combining this fact that the pill can increase your risk of depression with these headlines.
You also see that the pill changes your brain.
So there are studies that have found structural changes in the brain in people who are on hormonal birth control.
And these are studies where they put someone in an MRI.
They'll see sometimes that on the pill, areas of the brain are smaller or thinner.
One study actually found that a person's cerebral cortex shrank after being on the pill.
So you could see why people, you know, link this kind of stuff to what's causing depression.
But Caitlin Taylor, who's a neuroscientist at the University of California, Santa Barbara, she says that this is not the right interpretation here.
And she pointed out that changes to the brain are not necessarily bad.
Even studies that find a shrinking of the brain are not necessarily a concern because we know that the brain often shrinks in order to re-sculpt itself.
And these ideas are huge right now.
Especially when we're younger.
So, for example, kids, studies have found that they actually lose gray matter as they learn.
And, in fact, more gray matter loss is associated with better test scores and even higher IQs.
Even putting that aside...
Not every study finds brain shrinkage happens on the pill.
Like, there are some studies that have showed the opposite, that women had increased gray matter on the pill compared with women not on the pill.
Even Elon Musk is worried about this.
So it sounds like pinning the depression mechanism on changes in the brain is not a good idea because we're still working out what these changes mean at all.
And what's maybe surprising is that some people's mental health gets better on the pill.
So it's a mixed bag.
And we think the mechanism probably has more to do with...
Well, we know there's tons of receptors for these hormones in the brain, that they interact with neurotransmitters like serotonin.
So when you take these hormones in the pill, estrogen, progestin, it can interact with these neurotransmitters in our brain.
And it's more likely that's to blame for increasing our risk of depression than the pill changing your brain.
After the break, does the pill make you put on weight?
Plus, get excited because we are going to go on a magical journey into the world of pre-cum.
That's pre-cumming up.
Here he is talking to feminist icon Tucker Carlson in a video that's been watched millions of times, saying that women just don't understand how dangerous the pill is.
Welcome back today on the show, The Pill.
So far, we've learned that you should not trust Elon Musk when he tells you that birth control is going to make you attracted to people that you otherwise would not be attracted to.
And now let's talk about weight gain.
Yeah, and belief that the pill makes you gain weight is, this is important to talk about because it's a very common reason that people avoid taking the pill or stop taking it.
And there are potential mechanisms here, like why this might be happening.
So one idea here is that maybe the pill, something about the hormones in the pill, cause your metabolism to slow down.
And so researchers have actually tested this in monkeys.
They gave monkeys in a lab a birth control pill every day for eight months.
They also measured their metabolism before going on the pill and after.
And because these were monkeys in a lab, they were able to keep their food the same.
So if there was any weight gain, they could be confident it was because of a change in their metabolism.
So what did they find?
They actually lost weight.
The monkeys lost weight.
They didn't gain weight.
They lost weight.
Which suggests that their metabolism increased slightly.
And we know that they lost fat, not muscle.
And then from the studies that we have in people...
Well, they don't find that people lose weight on the pill.
They also don't find that they gain weight either in comparison to, you know, like some kind of control group.
Interesting.
So another pill myth busted.
The pill does not cause weight gain.
That's right.
And let me just bring up another thing that drives me kind of crazy, which is all this chatter about how dangerous the pill is and how many side effects it has.
You know, a lot of what people point to is stuff that's either really rare or it's not even confirmed to be linked to the pill.
And in reality, most researchers in this space agree that there's basically two major risks from the pill the average person should know about.
And again, we're talking about the combined pill.
So one is blood clots.
Your risk will go from maybe 3 in 10,000 to maybe 6 in 10,000 once you're on the pill.
And the other is breast cancer.
And the risk for that goes from like 5 or 6 in 10,000 to about 7 in 10,000.
So small increases we're talking.
And also, you know, the pill will actually reduce your risk of some other cancers.
So namely endometrial cancer and ovarian cancer.
So, Rose, we've gone deep on some myths and not-so-myths around the pill.
But the pill is not the only game in town here.
If you are a vagina and you're looking to have sex with a penis and you don't want to get pregnant, yeah, of course there are other options.
But there's one in particular that I want to zoom in on because it's gotten a lot of attention online.
And people are saying it's this great alternative, this revolutionary new way to manage your fertility.
Fertility awareness?
Listen to your body?
This isn't new.
It's kind of the oldest game in town, actually.
So for those unfamiliar, break it down for us.
So in a nutshell, this idea is that if you have a 28-day cycle—
Day one being your period, then day 14 is roughly when you ovulate.
And so you would avoid having unprotected sex in the days just right around that time.
And if you're just looking at a calendar to do this, studies have shown that the failure rate here can be as high as 25%.
And with all these concerns, some people are saying bye-bye to the pill for good.
Oh, if you don't want to get pregnant, that is not a successful, no, that's not good at all.
And this could be because it's just not a great way to pick up ovulation.
Like we talked about with the study on masculine and feminine faces, there's too much variation in the average person's cycle.
Yeah, that's why those studies were so bad, right?
But to be fair to the TikTokers, they're often talking about adding other observations to make this method more successful.
Things like looking at your cervical mucus, as I like to call it, the gunk in your underwear.
I talked about this with Jasmine Patel.
She's an OB-GYN at the University of California, Irvine.
It's time for me to come off the pill.
So if you're like looking down and you're producing your own lube, that's an indication that you might be ovulating?
It's a little bit more involved than just looking at your dirty panties.
A lot of experts recommend putting a couple fingers in your vagina and then checking the texture of what comes out.
When you're ovulating, it's kind of like egg whites.
You could also use those pee strips that we mentioned earlier that check hormones to see if you're ovulating.
And there's another method where you track your temperature by taking it first thing in the morning with a very sensitive thermometer.
So there are all these different formulas and apps for putting this data together in order to guess when you're about to ovulate.
Which means, like, this is the time when you can get pregnant.
And so if you do this perfectly, these methods can be up to 99.6% effective.
That puts it up with the pill, right?
That's about the same as perfect use of the pill.
So would you use this?
You know, I was really surprised that this could be so effective and that the TikTokers are kind of right here.
Like, oh, there is a fertility awareness method that can be 99% effective.
The pill burst onto the scene in the 1960s, and for tons of folks, it was seen as this wonderful thing.
That's really cool.
But I'm still kind of like uncomfortable with how this gets tossed around on TikTok because, you know, we only have a few studies really on these methods.
While for the pill, we have tons of studies and many thousands of people and all these different circumstances.
So we can just be much more confident about the effectiveness there.
And then also, you know, these methods take a lot of work and a lot of careful planning.
You got to think about this, track it every day.
And Jasmine says it's not always smooth sailing.
So fertility awareness methods, they are an option and they're not a bad option.
But be aware that just like condoms, they can have holes in them.
So while we're talking about condoms, let's talk about the penis in this equation here.
We don't have hormonal birth control for them yet, but there are non-hormonal options.
Obviously, they could wear condoms.
They could get vasectomies.
They could also not ejaculate in the vagina, right?
Today on the show, could the pill be changing us in these weird and even dangerous ways?
They could pull out.
Pull out method.
But I guess there has always been this question of, can you get pregnant from pre-cum?
A classic, which we have been...
I'm tantalising the audience with the answer of this question for probably half an hour now.
blow your load.
You pull out, out it goes.
Yeah, that's how it works.
And, you know, you watch American Pie and movies of that vintage, they'll talk about this, like, fear of pre-cum.
But scientifically, we didn't know if there was enough sperm, good sperm, in pre-cum to make someone pregnant.
And if you don't want to get knocked up...
So what do we know now, Rose?
We have new research on this.
It just came out.
Hot off the pre-cum press.
And it's from Jasmine.
So she did this great study about looking for swimmers in pre-cum.
She got men to come to a clinic.
should you switch to something better?
I thought she just got men to come.
came into the clinic, I'm like leaving no pods at all.
And to masturbate, kind of to give a sperm sample, but doing it a little differently than how you might otherwise give a sperm sample.
So to collect the pre-cum, she basically had the guys masturbate into a Petri dish.
There's a lot of buzz about this exciting, hormone-free, natural method that's out there.
So the guys had to press the tip of their penis onto the Petri dish as they jerked off.
They'd have to be experienced.
Jerkers for that.
I think we can assume they were experienced jerkers.
That's a fair assumption.
So then the dribble or whatever was coming off the penis before ejaculation could kind of just spread across the dish without losing a drop.
We're also going to get to the bottom of a question that we at Science Versus have had for half a decade, which is, can you really get pregnant from pre-cum?
So what happened next?
Well, what happens next is the men come, but they pull their penis off the dish and into a cup.
So what she was looking for was, do the men have at least a million healthy swimmers per milliliter?
That's what scientists think that you need to get someone pregnant.
Interesting, right?
But here's the catch.
Oh, that's annoying.
Because if you're having sex with a penis, or if you are the penis, you don't know if you're a sperm-filled pre-cum haver or not.
Ultimately, out of 24 people in Jasmine's study, five sometimes had enough sperm in their pre-cum to get someone pregnant.
I don't know.
It depends.
Like, I think some people see the pre-cum as half full and some people see the pre-cum as half empty.
I mean, you can look at it.
You know, the thing with birth control, and here's something that has, like, really been driven home to me as I've been working on this episode, is, like,
Everybody's risk tolerance is different.
Yeah, that's, of course, of course.
And I think, I mean, what I do really like, I guess, about this new conversation around the pill is because for so long there really has been this just assumption that women and folks with vaginas are going to be taking it.
And for some people, as you've talked about, there are side effects.
It does affect their mental health.
It may lower their libido.
And there are those, you know, very rare risks around breast cancer and blood clots.
And so it is right to ask yourself, you know, if you're starting to have P and V sex, is this right for you?
And if not, what else is out there?
And can we start putting a little pressure and responsibility on the penis in the equation?
When it comes to the pill, there's at least one billionaire saying it all.
So for that reason, it's great.
Yeah, I agree.
But I do think that they can go overboard with that messaging.
Because what online creators are trying to do is to get your attention.
And so saying that the pill is dangerous, there's a marvelous new method that's perfect, saying all that stuff gets eyeballs.
It's not about...
Responsible communication about reproductive health.
But that's what you come to Science Versus for.
Responsible communication about reproductive health and the real science on Precom.
We always find the important and meaningful stories to bring to you, our beloved audience.
And that is Science Versus.
Rose, how many citations are in this week's episode?
This week we have 75 citations.
And if people want to see more, learn more about the pill, where do they find these citations?
But then there's science.
They can check the transcript, and there is a link to the transcript in our show notes.
And on social media this week, anything fun?
We're going to put some pictures of the masculine or feminized male faces so the listeners can play Spot the Difference, too.
And we could throw in a picture of a chimpanzee in heat.
I'll make that happen.
Our Instagram is science underscore VS. And my TikTok is at Wendy Zuckerman.
So come say hello.
Thanks so much, Rose.
Thanks, Wendy.
This episode was produced by Rose Rimler, with help from me, Wendy Zuckerman, along with Michelle Dang, Ekedi Foster-Keys and Meryl Horne.
Science versus the pill is coming up just after the break.
We're edited by Blythe Terrell.
Fact-checking by Eva Dasher.
Recording assistance from Emile B. Klein.
Mix and sound design by Sam Baer.
Music written by Bobby Lord, Bumi Hidaka, Peter Lennett and Emma Munger.
Thanks to all of the researchers that we spoke to for this episode, including Dr. Adrian Beltz, Professor Alison Edelman, Dr. Emily Fender, Professor Jayshree Kulkarni, Dr. Jill Kraft, Dr. Rachel Urrutia, and Dr. Therese Johansson.
Special thanks to Maya Foster.
Science Versus is a Spotify Studios original.
Listen to us for free on Spotify or wherever you get your podcasts.
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But if you are listening on Spotify, then tap the bell icon so you get notifications when new episodes come up.
And also, if you like the show, please rate us, give us a five-star review.
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Thank you so much for listening.
I'm Wendy Zuckerman.
Talk to you next time.
Welcome back.
Today we're here to talk about the pill and we are going to do it with a real pill.
Senior producer Rose Rimler.
Country singer Loretta Lynn even wrote a song about how the pill was going to open up all of these possibilities for women.
What made you want to do this episode?
Well, I've just been seeing a lot of stuff online about how the pill isn't as safe as we thought it was and how it might be changing us.
And those are very interesting claims to dig into.
And they're also very relevant right now with all this uncertainty about access to contraception and abortion in the U.S.
And, you know, that's not the only reason people take the pill, but it still just seems like a really good time to dive into this.
Yeah, for sure.
I do think for a long time there's just been this assumption that women are going to go on the pill.
You'll go on the pill, right?
And so I think really questioning what is it doing to us, I think is really important.
Okay, let's start with something that I've been saying a lot of recently, but it's sort of been rolling around for years now.
And it's this idea that the pill will change who you're attracted to.
Which is all part of this sort of larger idea that the pill, because of the way it affects hormones, it like fundamentally changes who you are.
So what do we know about this?
I really enjoyed looking into this.
So let's dive in.
It's very interesting.
So this all comes from the fact that the combined pill, which is the typical birth control pill, stops you from ovulating.
And that's how it works.
That's how it keeps you from getting pregnant.
Ovulating is thought to be important for things like sexual attraction.
So there's this theory out there that when you're ovulating, as in you're ready to make a baby, you're attracted to a different kind of guy than you are the rest of the month.
This theory predicts that if you're into guys, you would go for a more masculine kind of guy around that time.
That's basically the idea.
So I talked about this with Julia Stern.
She's a psychologist at the University of Bremen in Germany.
This is the show that pits facts against fallopian tubes.
If you're fertile, you might be interested in a very masculine guy.
And when you're not fertile anymore, you might be more interested in the good guy.
So when you're in your fertile window, you are attracted to someone like Dwayne The Rock Johnson.
But then when you're outside the fertile window, you're more like a Timothee Chalamet kind of girl.
Is that what's going on here?
More or less, yes.
So, of course, Dwayne The Rock Johnson is, like, extremely muscular and has a very deep voice.
Do you think those are appropriate celebrities to pick?
I mean, Dwayne The Rock Johnson is pretty accurate, maybe, but what about Kevin James, for example, for...
For the good guy.
Wasn't he the king of queens actor?
There's a meme that went around of him, like, shrugging, like, shyly shrugging.
Oh, yeah, but I know that meme.
What are you seeing in this picture that makes you say, oh, yeah, that's it?
Well, it's a smile, maybe, like this...
It's like, I'm not here to vanquish your enemies.
I'm here to, like, give you a nice hug and hand you a cup of tea at the end of the day.
And then play with the children after coming home from work.
So, Wendy, I know that sounds like something totally made up on, like, a dumb podcast.
Not this one.
Not this one.
Like a dumb podcast.
But scientists are, like,
Into this idea.
This idea that when you are ovulating, you're attracted to different kinds of men.
Yeah, this is a real concept in the scientific literature.
And the concern is that if you never ovulate, you never have that natural shift towards the rock.
You're going to be permanently stuck in the Kevin James portion of your cycle.
And the freedom that she's singing about, about choosing when to get pregnant and how many babies you're going to have.
I know, you hate this stuff.
Has anyone actually tested this?
They show women pictures of men and they've altered the men's faces to be either more masculine or more feminine.
That's pretty subtle.
I can show you some of these manipulated faces.
So this is two different people.
The image on the right has been masculinized.
The image on the left has been feminized.
I'm very good at playing, you know, that kids game spot the difference.
So this is really harnessing some of that power.
The nose looks a little more pinched in the quote unquote feminized version.
The brow looks a little lower.
The eyes look a little bigger in the feminized version.
So they give people and they say, who are you more attracted to?
Yeah, and a number of studies have actually found that women prefer a more masculine face around the time they ovulate and a less masculine face the rest of the month.
It just resonated with loads of women.
And women who are on the pill, studies have found that they always prefer the less masculine face.
So these studies are all done in presumably straight cis women, by the way.
And that's true for like all this research.
So yeah, that's what a lot of studies have reported.
And actually a review paper that came out in 2014 said that the effect of birth control on mate choice is, quote, relatively robust.
In fact, since the pill came out, women are more likely to go to college, become lawyers, judges and doctors.
Relatively robust.
That's what they said.
And when I read that, I was like, oh, like, okay.
And, you know, the stakes are kind of big here because what this suggests is that if you're on...
Birth control, when you meet someone and then you go off it after you're married or vice versa, maybe you end up with someone who is not the partner you would have otherwise chosen.
And that is freaky.
In fact, some data suggests that people who use hormonal birth control had 50% higher odds of getting divorced.
Do you feel like who you're attracted to changes depending on where you are in your cycle?
Julia doesn't either, actually.
And that's one reason she wanted to get into this.
I never experienced that.
None of my friends has ever told me about that.
But at the same time, sometimes in science, effects are really small and we are not really able to perceive them.
But that kind of still happens unconsciously.
Plus, the wage gap between men and women has narrowed by 30%.
So Julia looked at these studies more closely and she realized something kind of odd.
in these studies.
And that is that in a lot of them, we really can't be sure that the women were definitely ovulating when they were tested.
So most of these studies just estimated where people were in their cycle based on the date of their last period.
So they just assume like, okay, if you're on day 14, you're probably in your fertile window.
But the reality is cycles vary a lot in length between women and also within women.
It sounds like you're saying these studies were trying to figure out if women had a different preference when they were ovulating, but they didn't actually double check the women were actually ovulating.
And some economists say that this is a direct result of the pill.
Is that true?
Yeah, that's basically the point, yes.
Sounds pretty bad.
That is bad.
Also, because it's so easy to check.
I mean, now you can pee on a stick.
Probably when these studies were done, you do a blood test.
Yeah, I know.
And so over the past decade or so, there have been all these studies that do actually check people's hormones and find out, OK, are you for sure ovulating?
And then they get them to look at faces.
And guess what, Wendy?
These studies, they don't see this effect.
No, they don't.
Of course they don't.
I mean, you think about how many bullshit studies came out that didn't actually test if women were ovulating.
How many think pieces have been written about this evolutionary theory around masculine virile men and who's attracted to them?
But you fast forward to today, and for many, the pill has gone from hero to zero.
But then what about...
The research that shows that people on the pill are always in the Kevin James portion of their cycle.
That doesn't hold up either in newer studies, bigger studies.
So there's this one big study that came out pretty recently.
It was almost 6,500 people.
They showed these faces to women on the pill versus not on the pill.
No difference.
No difference.
So if you are on the pill and you are worried about this, you do not need to be worried about this.
That's what I would say, yeah.
And can we just talk about the smell thing?
The smell thing?
Wendy, there is this idea that men can sniff out ovulating women and that they find them more attractive.
And so, therefore, men won't find you as attractive while you're on the pill.
Had not heard this theory, but from an evolutionary perspective, I would actually buy it more than that masculine, feminine garbage we just talked about.
Why is that?
Because it makes sense that for animals like humans who ovulate...
on a cycle every month that there is some evolutionary pressure that has allowed males to sense when they might be fertile.
People say that pumping ourselves with these hormones can be harmful.
Because it does take energy to blow your load.
So you want to make sure you're putting it in the right place.
So smell, sure.
I mean, that's interesting you bring that up because a lot of the idea here is that
A lot of animals display when they're ovulating, including other primates.
So some of them have this like huge swelling of their anus and vulva when they're ovulating to be like, I am ovulating.
Come and get me.
I just clenched.
I just clenched.
But then humans, we don't seem to.
So we have what researchers call concealed ovulation.
But then other researchers have been like, wait, maybe it's not really concealed.
Maybe it's just very subtle.
And so they have actually done these studies to try to figure out, are there subtle little cues that men can pick up on that women don't even know they're giving off?
And that the pill is interfering with, ultimately.
And yes, and if that's so, then the pill could interfere with it.
And there's some very modern research on this.
I spoke to someone who wanted to get to the bottom of that.
I wanted to assess whether there is something in women's body order that changes during the menstrual cycle.
And that it can even change parts of our personality, like who you're attracted to and also who is attracted to you.
Medita Setsha, she wanted to actually do a chemical analysis of armpit odor over the course of the cycle.
The idea here is to find out if the smell changes, and if so, can men tell?
And then do they like it?
This is great.
This is great.
So they recruited about 30 young women to come into the lab a bunch of times over the course of their menstrual cycle.
And every time they came in,
Medida's team sucked up a little bit of their BO with this special equipment.
What did that look like?
Well, you said straw.
I'm imagining like you're on the other end, like sucking it up.
A little pump?
So they're pumping out the sweat.
It's not the sweat.
It's the odor emitting from the armpits.
This little machine would suck out the odor.
And they knew where the women were in their cycle.
They gave them a pee test and a saliva test.
This is a good study.
Well, here's how Medida put it.
There was no compound or a combination of compound which was indicative of, let's say, ovulation or the fertile window.
So, it's not going great.
but I'm not giving up.
I'm too curious.
I want to know what it feels like to walk around inside my own mind.
And soon I start looking around online for things to help me.
There's this drug that people talk about called galantamine.
A playground to be whoever you want to be.
It sounds like something out of Lord of the Rings, but we think it keeps you in REM for longer than normal, and researchers actually found that it can up your chance of having a lucid dream.
But it's only really been studied by getting people to take the drug when they wake up at stupid o'clock anyway while they're doing the technique that we're already doing.
Plus, the drug has some side effects.
So, forget it.
There are also masks that you can get for sometimes thousands of dollars claiming that their lights or sounds can help you, quote, unlock the world of lucidity where everything is possible, end quote.
And the idea behind some of these masks is actually really interesting because there is research that shows that if you, for example, play someone a particular sound, like three beeps, while they're awake and doing a set of instructions about becoming lucid when they're dreaming, and then you play that same sound when they're asleep, it could cue you to become lucid in that moment.
And for some folks, this isn't just a bit of fun.
But when it comes to these masks that you can buy online, very few have actually been tested or shown to work.
They're also trying to use lucid dreaming to improve their mental health, overcome fears, and to understand themselves better.
After the break, we go deep inside the brain to find out how people can control things in their dreams.
Welcome back today on the show, Lucid Dreaming.
And now let's find out what is happening in our brains as we go on these grand adventures and have a lucid dream.
So if you want to know what's going on in someone's brain as they're lucid, you first have to know the moment that that person who is fast asleep has become lucid.
But they're asleep, right?
They can't tell you.
Well, decades ago, researchers worked out a kind of bonkers way to do this.
And I talked about it with Dr. Bashak Turka, a cognitive neuroscientist at Parasite University.
So she told me that lucid dreamers will come into a lab.
That's how my friend Archer used lucid dreaming.
And the bat signal that researchers chose is that the lucid dreamers would move their eyes all the way to the left.
and then all the way to the right.
And they do that a couple of times.
And all the while, they'd have sensors on their face and head to detect eye muscle movements and to make sure that they were sleeping.
With this bat signal, scientists can now probe what's going on in someone's brain while they're lucid.
Which brings us to the story of Bashak and a lucid dreamer who we'll call AC.
He's the guy going flying down the staircase.
AC has narcolepsy, which is a sleep disorder where you fall asleep randomly throughout the day.
And for reasons we don't fully understand, it's linked with lucid dreaming.
This is AC.
Because no one wants to hear about your dream.
AC had been involved in some lucid dreaming experiments where he had to do the bat signal to indicate he was lucid.
But he wanted to boldly take lucid dreaming science where no one had gone before.
Archer is a trans man.
And Bishak and her colleague were intrigued.
He wasn't born with a penis.
The plan was simple.
Bashak and her colleague would ask him yes-no questions while he was fast asleep, but lucid.
And he would try to answer them, smiling three times for yes and frowning three times for no.
And this is something that for years science had thought was kind of impossible.
I mean, sometimes you might ask a partner in the middle of the night, hey, did you take the trash out?
And for years now, he wished that he had one.
And they kind of respond.
So if you look at their brain activity, you can see that they're not asleep in that moment.
You might have woken them up.
We also know that in some of the earlier stages of sleep, you are aware of the awake world.
But once you are conked out, dead to the world in deep sleep or REM, you're not supposed to answer questions.
So, Bashak and her colleague put sensors all around AC's head and face to measure whether he's asleep and what his mouth muscles are doing.
Bashak tells AC, nighty-night, or whatever scientists say to each other.
And AC lays on the lab bed and goes to sleep.
AC is in deep sleep, and they could clearly see it on the sensors.
But in his dream, he was in an epic battle.
He becomes lucid and signals to Bashak using the bat signal.
And here's where it gets weird.
AC remembers hearing those questions from within the dream.
And when Bishak sees the smile, she's not sure it's real.
And you're fighting goblins at the same time.
And while AC is having a fine time, Bishak and her colleague were starting to freak out.
And as Bishak is smiling about this discovery in France, other researchers in the US, Germany and the Netherlands are having similar experiences.
In one lab, researchers even asked a lucid dreamer, what's eight minus six?
And while he was asleep and lucid, he responded using the bat signal to indicate two.
After Bishak saw this, she studied it in more lucid dreamers, who, by the way, all had narcolepsy.
And she switched up the experiment a little bit.
So this time, while they were asleep, they'd hear all of these fake words like ditzer and then real words like pizza.
And they had to smile three times for a real word and frown three times for a fake word.
Now, sometimes they didn't respond at all.
But a bunch of times they did.
And they answered correctly.
But then Bishak noticed something weird.
At times, they would answer the question accurately, smile or frown, while they weren't having a lucid dream.
So we got a bit curious, confused and excited at the same time.
So then she recruits 22 folks who couldn't lucid dream and also didn't have narcolepsy, and she repeats the experiment.
Wait, so if I went to sleep now and you started asking me, what's a word, pizza or pizza, chances are I would respond?
But the thing is, the lucid dreamers were answering the questions a lot more often.
So this tells us that even when people aren't lucid dreaming, there are these small windows where parts of our brain can listen to the outside world around us and can even figure out whether a word is real or made up, which upends what many of us had thought about what was going on while we were sleeping.
But there was something particularly special about what was going on in the brain of someone who was having a lucid dream.
And that meant that those windows where they could respond to the awake world, they were open more often.
And in Bishak's study, she saw an important clue as to why this might be.
But not so rich that they woke up.
Other research is helping us to explain how we can even have a lucid dream in the first place.
We think a brain area called the prefrontal cortex is important.
So normally when you're dreaming and not lucid, the activity in this part of the brain winds down, which Bishak says might explain why weird things can happen in your dream, and that's fine.
How big was this for you?
But we think, based on limited evidence, that while people are lucidly dreaming, this critical area of your brain is more awake.
How big was the moment, Arj?
And because lucid dreaming is this hybrid state of consciousness, you know, between being asleep and awake, researchers like Bashak now want to use lucid dreaming to help us understand what consciousness is at all, which remains, according to one review, quote, one of the largest lacunas in scientific knowledge.
And to save you the time, I googled it, and lacuna means unfilled space.
And just quickly, some lucid dreams can actually be felt throughout your whole body.
Like if you ask lucid dreamers to hold their breath in a dream, you can see that air stops flowing through your nose and your blood oxygen levels drop just slightly.
In another study, someone had an orgasm in their lucid dream and researchers could measure more blood flowing to her vagina.
So how close are we at Science Versus to having what she's having?
A week has gone by and by now have we unlocked this hybrid state of consciousness?
Everyone say yay if you've had a lucid dream.
One, two, three.
No luck.
No luck.
You actually have this superpower.
Has this supercharged your superpower?
So let me tell you, I woke up and had been in the middle of this dream where me and my, where there was this sort of creepy oval.
I'll just jump in and spare you the pain of listening to too many of my dreams.
So basically what happened is that I woke up from this dream where a bunch of bonkers stuff is going on.
I was getting attacked by bats.
And just as denim study suggested, I tried to think of all of the wacky things that clearly made this a dream.
But in that moment, in the middle of the night...
I couldn't think of any reason why it was obviously a dream.
And then I went back to sleep.
The next night, another dream.
This time I'm in a tunnel on the beach about to drown and I've got my laptop.
I wake up and, well, as I told Blythe and Rose...
And the same thing happens.
What about this was clearly a dream?
And I'm like, well, there could be a tunnel.
I could have brought my laptop to the beach.
And the second time it happened, I realized maybe I was sleeping the whole time.
Have you since practised lucid dreaming for any other kind of sexy dreams?
I think maybe both times I didn't actually wake up.
If I was asleep the whole time, this is known as a false awakening.
And curiously, academics have actually written about this phenomenon where your dreams try to convince you that they're actually not dreams.
AC says for him, this happens all the time.
It's the people in his lucid dreams who tell him this is not a dream.
And Denim and Bashak told me that when you think about the neuroscience of lucid dreaming, in a weird way, this kind of makes sense.
This is a magical power you have.
Can we use lucid dreaming to help us in our lives, to be happier people?
Well, in one survey, many folks said that having a lucid dream helped them when they were feeling depressed or low.
One person said that after a lucid dream, they could have this happy and beautiful experience that would stay with them for days.
Another said, quote, it can kickstart your day and keep you warm.
And a small study found that the day after people had lucid dreams, on average, they felt less stressed.
But be warned, if you're waking yourself up in the middle of the night to try lucid dreaming, we know that messing with your sleep can be bad for your mental health.
So today on the show, we are going to teach you how to lucid dream.
And curiously, some research has actually found a link between being depressed and having more lucid dreams.
We're not sure why.
And just quickly, the last thing we want to look into is whether lucid dreaming can help people who have horrendous nightmares.
Which, if this happens to you regularly, it can be awful, making you anxious, having difficulty sleeping.
That's right.
Scientists have studied the best way to get this superpower.
Brigitte Holtzinger is a psychologist at the Medical University of Vienna, and she has studied this herself.
She's recruited people who were having terrible nightmares about being assaulted, run over by a train, hunted by a monster...
She'd teach them how to lucid dream.
And she told me that it really did help some of her patients.
There was one person who used to have these really frightening dreams of being chased where they had to escape.
But after learning to lucid dream, they told Gita...
And we will reveal their peer-reviewed secrets.
Oh, wow.
Now they could have fun with it.
Now there's true realisation it's just a dream.
But unfortunately, the evidence that lucid dreaming can help loads of people conquer their nightmares, it isn't so impressive and wonderful.
We now have several rather small studies, including Gita's, and there's a new one that's been making headlines, that show that after getting people to try lucid dreaming, they do report fewer nightmares.
We'll also explore how researchers are trying to harness the strange powers of lucid dreaming to help people through trauma and depression and to crack these huge scientific mysteries like what is consciousness and what exactly goes on in all of our heads when we're asleep.
But these studies combine lucid dreaming with intensive therapy.
And it's really hard to tease out what's doing the heavy lifting here.
Plus, surveys find that even when people become lucid in their nightmares, they often can't change what's happening.
So they'll be stuck in this terrifying dream.
And just knowing this is a dream, it's not real, that isn't necessarily that helpful.
In fact, in a survey including more than 30 US veterans with PTSD who could lucid dream, only three said that they felt relieved to know that they'd been dreaming.
Many just felt anxious about it.
So even this superpower has its kryptonite, its limitations.
But despite that, just like Superman, I still wanted to fly.
I switched up the lucid dreaming method a little bit just so I could sleep better, but kept trying.
And still, the closest I'd gotten is realizing that I'm in a dream, but then getting too excited and waking up before I could do anything.
I talked to Gita about it, who gave me one final piece of advice.
Blythe, Rose, it's the end of the episode.
Everyone say yay if you had a lucid dream.
One, two, three.
Oh, my God, Wendy.
I know.
I did it.
I did it.
Oh, my God.
Do you want to hear the voice message I made straight after?
In the dream, I was lying on my bed and my entire ponytail came off.
And I was looking at it going, ooh.
Then I was like, no, wait, this is a dream.
Ponytails don't just pop off.
This is a dream, this is a dream, this is a dream.
When it comes to lucid dreaming, there's a lot of... Let's fly.
And then I put the ponytail down on the bed and I just felt it.
Like how everyone says you just feel because things feel so real.
And it did.
And it did and it did.
And it felt like my hair.
It felt like my hair.
All the little strands.
And then there's science.
That's Science Versus.
This episode has 99 citations.
So if you want to read more about the science of lucid dreaming, then you just need to go to our show notes and click on our transcript and there's a link.
Science vs. Lucid Dreaming is coming up just after the break.
And you'll see all that wonderful science there awaiting you.
If you want to tell us about your lucid dreaming experiences, I would love to hear it.
You can find us on Instagram.
We're at science underscore BS.
And I'm on TikTok at Wendy Zuckerman.
This episode has been produced by me, Wendy Zuckerman, with help from Rose Rimler, Michelle Dang, Meryl Horne, Joel Werner and Akedi Foster-Keys.
We're edited by Blythe Terrell.
Fact-checking by Erica Akiko Howard.
Mix and sound design by Sam Bear.
Music written by Bobby Lord, Bumi Hidaka, So Wiley, Peter Leonard and Emma Munger.
Thanks to all of the researchers that we spoke to for this episode, including Dr. Karen Conkley, Dr. Benjamin Bard and Professor Ken Paller.
Also, a big thanks to the Zuckerman family and Joseph LaBelle Wilson.
Science Versus is a Spotify Studios original.
Listen to us for free on Spotify or wherever you get your podcasts.
If you are listening on Spotify, then follow us and tap the bell icon so you'll get notifications when new episodes come out.
And if you like the show, please give us a five-star review.
It really helps people find the show.
I'm Wendy Zuckerman.
Back to you next time.
Welcome back.
Today, we are flying into the dream world, or at least we're trying to.
And if we want to channel lucid dreaming to improve our lives, the first step is to learn how to do this.
Because for many of us, it doesn't come easy.
I mean, studies find that around half of us will have had at least one lucid dream in our lifetime.
But not all lucid dreams are created equal.
For me, the best I've gotten is that I'll realise I'm dreaming for a moment and then I either wake up or go back to regular sleep.
Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
And my lacklustre lucid experience is pretty common.
One study reckoned that only around a third of people who lucid dream can manipulate what they're doing in their dreams.
So how can we up our game and learn how to become gods in the dream world?
For this, we need Dr Denham Adventurehart, a psychologist in Brisbane, Australia.
Denim lives with sciatica, which can cause this nasty pain throughout his body.
Today on the show, we're pitting facts against flying as we swoop into the world of lucid dreaming.
And several years ago, things got really bad.
There were some days when he could barely get out of bed.
Well, unless he was lucid dreaming.
Every now and then, Denim would find himself in a lucid dream
And there, he could escape his illness.
The problem was that Denim couldn't play in this playground very often.
He'd go to sleep and night after night, no running, no new worlds.
And he'd wake up still stuck in bed, in pain.
So Denham decides that he's going to train himself to get better at lucid dreaming.
And he gets really into this thing called reality testing or reality checks.
And these are huge in the lucid dreaming world.
There are people that have a superpower where they know that they're dreaming and sometimes can even control what happens next.
I mean, just ask Christopher Nolan about it.
It was an inception.
So to understand how this could work, it's helpful to know that often people will spontaneously have a lucid dream because they'll be stuck in the middle of a dream and something really weird will happen that makes them think, what, this has to be a dream.
And voila, they're lucid.
And so reality testing is all about trying to hack that process.
So here's what Denim would do.
While he was awake, he'd close his mouth tightly and then try to inhale through his mouth.
Wait, I want to try it.
So you've got your mouth closed.
If you think you're doing this, you're actually breathing through your nose.
So the fact that you can't do it tells you that this is not a dream.
You are awake and listening to this podcast.
But Denham had read that in dreams, you can breathe through a closed mouth.
And that was true for him.
Another super popular reality test is trying to poke your finger straight through your palm.
Obviously, while you're awake, it doesn't work.
But in the dream world, people say that your finger does go through your palm.
And so the idea here is that you will do these reality checks tons of times throughout the day.
And because most dreams are reflections of the stuff that we're doing throughout our day, you hope that then in a dream, you will also do a reality test.
And in their dreams, people all over the world are saying, Okay, great, let's fly.
And when you feel that air moving through your closed mouth or you see your finger slip through your palm, then you'll realize this is a dream and you'll be lucid.
So Denim is sick at home and he's doing these reality tests a lot.
But it was strange because he wasn't having that many lucid dreams.
And so was it frustrating?
So Denim starts thinking, what's going on here?
Is it just me?
And being a scientist, he decides to study it.
He sets up an experiment recruiting more than 350 people from all around the world, making this the largest study I could find on inducing lucid dreams.
To get a baseline for seven days, everyone would record how many dreams they were having and how many of those were lucid.
Then Denham puts everyone into different groups.
Some are told to practice reality testing.
They do it for seven days.
And guess what?
That's very interesting because even then I have spoken to quite a lot of lucid dreaming academics and asked them all, how should I do this?
And they've all said, you should try reality testing.
Like it's so embedded in the zeitgeist around lucid dreaming.
And yet your study found it actually didn't work.
Other smaller studies have found this too.
On average, we can't see a statistical link between reality testing and having a lucid dream.
And one reason for this could be because reality tests can fail.
in that even in your dream, you still can't put your finger through your palm, which makes perfect sense.
We know that dreams are super subjective, unlike what you might read on a lucid dreaming Reddit post.
There's no physics or biology in the dream world that means your hands are made of putty.
But in Denham's study, he was testing other lucid dreaming techniques as well.
And he did find something that worked.
It's called mnemonic induction of lucid dreams.
And in Denham's study, on average, about one in six times that people tried this method, they had a lucid dream.
One in six.
Wow, that's a pretty good rate.
Here's what you've got to do.
You set your alarm clock.
That's rubbish, five hours.
And the insanely almost magical thing about lucid dreaming is that people who do this will tell you that it feels real.
You're waking up at around 4 or 5 a.m.
because you're trying to catch yourself in REM sleep, which is where most of us have our lucid dreams.
So you're trying to remember the dream that you were just in.
You're visualizing yourself being back there.
And what you're doing is trying to notice something unusual that might make you realize, hey, I'm dreaming.
And as you're awake, repeat this mantra.
Next time I'm dreaming, I want to remember that I'm dreaming.
In Denham's study, people were roughly three times more likely to have a lucid dream after doing this compared to that week where they weren't doing anything special.
And other studies have found that this technique works as well.
As a little tip, if you can go back to sleep quickly within five minutes after doing all the mantra stuff, you up your chance of having a lucid dream even more.
It's not like closing your eyes and imagining that you're flying or doing whatever.
Plus, the people in Denham's study who had never really tried lucid dreaming before had a similar success rate to those who were more experienced.
Do you think that everyone can have a lucid dream?
Like if they really put their mind to it, do you think we're all capable of this?
A learnable skill, you say.
You're really there.
Next time I'm dreaming, I will remember I'm dreaming.
In Denham's research, people who were far from lucid dreaming ninjas could learn this in just one week.
So my editor, Blythe Terrell, senior producer, Rose Ribbler, and I, we wanted to fly.
Actually, for Rose, she had a very particular dream that she wanted to conjure up.
Oh, wow, that's so cute, Rose.
So I explained how we were going to do this, that we'd wake up five hours after going to sleep.
We would try to remember the dream we were just in.
We'd think about all the weird stuff that obviously makes it a dream.
And then we'd say the mantra.
It should take five to ten minutes.
Confirmed.
Astute ears listening to this podcast might notice that Blythe was one of the voices you heard at the start of the show.
She was flying in a lucid dream doing those big loop-de-loops.
But Blythe can't do this very often, so she wants to see if she can supercharge her superpower.
And Rose and I are going to find out if we can control things in our dreams for the very first time.
I am not optimistic at all, in fact.
But I'm really trying to have a positive attitude.
All right.
Meet back in a week.
Give ourselves a week.