Testosterone: Do We All Need a Boost?

We’re hearing a ton about the marvels of testosterone from influencers, celebrities, and even government officials. They say we should be thinking about our T levels, topping them off with extra if they’re too low. And we’re told that the benefits of testosterone are HUGE: that we’ll be stronger, sexier, and more energized. So is that true?? And if you do go for a testosterone bump, do you need to worry about possible side effects, like ’roid rage, infertility and other risks? We talk to endocrinologists Prof. Shalender Bhasin and Prof. Richard Auchus as well as social psychologist Dr. Justin Carré to find out. Find our transcript here: https://tinyurl.com/ScienceVsTestosterone Find Wendy's chat about Bigorexia here: https://www.youtube.com/watch?v=hsZEfTWuIqg In this episode, we cover: (00:00) We’re obsessed with testosterone (02:59) Will T make you bigger and stronger? (09:25) ‘Roid rage (18:04) Will T turn you into a horndog? (25:48) Will T put pep in your step? (27:51) The risks of taking T (31:49) Why are we like this? This episode was produced by Rose Rimler, with help from Meryl Horn, Ekedi Fausther-Keeys, and Michelle Dang. We're edited by Blythe Terrell. Wendy Zukerman is the executive producer. Fact-checking by Marlowe Starling. Video editing and sound by Bobby Lord. Music written by Bumi Hidaka, Peter Leonard, Emma Munger, and Bobby Lord. Thanks to the researchers we spoke to for this episode, including Dr. Kathleen Casto, Dr. Carol Hooven, Professor Ruth Wood, Dr. Stephanie Page, Professor Sari van Anders, Dr. Adam Stanaland, and Professor Anthony Hackney. Thanks to Humdinger Studios in Melbourne and Wolf Island Studios in New York City. Science Vs is a Spotify Studios Original. Listen for free on Spotify or wherever you get your podcasts. Follow us and tap the bell for episode notifications. Learn more about your ad choices. Visit podcastchoices.com/adchoices

• 0:01Speaker 00

  Should you take testosterone? Hi, I'm Wendy Zukerman and this is Science Versus.

• 0:13Speaker 00

  All over the internet, people are saying that you need to be thinking about your testosterone. Taking T used to be something mostly done by bodybuilders. But now it's pretty mainstream, with prescriptions for T going up more than 10 times over the last two decades. That's according to an analysis from the New York Times. And our obsession with testosterone reached new heights when earlier this year, US Defence Secretary Pete Hegseth announced that he wants to screen soldiers for low testosterone in order to create a "high-T department of war." Why?

• 0:49Speaker 01

  As we know, the modern battlefield is brutal and unrelenting. It requires and demands maximum psychological and mental readiness.

• 0:57Speaker 00

  And online, you'll hear that we're in the midst of a testosterone crisis, with T levels apparently plummeting among men, who say that it's making them miserable. There's tons of videos out there where young guys give each other tips on signs to look out for to show that your testosterone is low.

• 1:16Speaker 02

  You get anxious out of nowhere, you can't grow facial hair, you stop caring about a lot of things, and you're awake at 3am every single night.

• 1:24Speaker 00

  Influencers tell us that women need to be thinking about their testosterone too, especially after menopause. And loads of folks, including celebrities like Joe Rogan and Halle Berry, swear that once they took extra testosterone, their life got better. They say their sex life improved, they felt stronger and more energized.

• 1:44Speaker 03

  Yeah, it makes a big difference. Fuck yeah.

• 1:47Speaker 04

  My brain fog basically disappeared. My libido came back.

• 1:50Speaker 05

  I actually feel like a man. I don't let shit slide. I feel like I have a lot more work ethic, more motivation, and I just want to beat my shit all day.

• 1:59Speaker 06

  Many women tell me they have better focus, they feel like they want to do more things than they did before, and they finally feel like themselves again.

• 2:06Speaker 00

  So what is going on here? Should we all be worrying about testosterone and taking a little T on the side? Or is this toxic masculinity on, well, steroids? When it comes to testosterone, there's a lot of...

• 2:22Speaker 05

  I just want to beat my shit all day.

• 2:25Speaker 00

  But then, there's science.

• 2:32Speaker 00

  Science vs. Testosterone is coming up. If you have a testosterone curious friend, share this episode with them. Let them know the real science on testosterone, which is coming up after the break.

• 2:52Speaker 07

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• 5:07Speaker 00

  Welcome back. Today on the show, the science of testosterone. Been in the news a lot recently and all over social media to tell us all about it. We have, of course, the beefiest, buffiest, fabulous science journalist, senior producer Rose Rippler. Hi Wendy.

• 5:26Speaker 06

  Hi Rose.

• 5:27Speaker 00

  Let's just jump in. And let's look at the biggest, literally the biggest claim out there about testosterone, which is, can it make you stronger?

• 5:37Speaker 06

  Bigger muscles, stronger.

• 5:38Speaker 00

  Bigger muscles. That's right. That's right. Which, you know, lots of people want right now. Could it help?

• 5:44Speaker 06

  So I talked about this with a scientist who specializes in studying testosterone. In fact, Wendy, he's responsible for some of the seminal research in this space.

• 5:57Speaker 00

  Was that a pun on semen?

• 5:58Speaker 06

  Yeah.

• 5:59Speaker 00

  Yeah.

• 6:00Speaker 06

  I got it. Good, good, good. I'm Shalender Basin, and I'm professor of medicine at the Harvard Medical School. Shalender said that early in his career, there was actually a big debate among scientists about this very question, whether taking testosterone actually does make you beefier or more athletic. So on the one hand, you had athletes that were getting into trouble for taking anabolic steroids, which are basically souped-up derivatives of testosterone. They're also sometimes called androgens. So take the famous case of an Olympic runner named Ben Johnson. This was in late 1980s. He was a sprinter, had a record, broke the records.

• 6:45Speaker 06

  And he was using anabolic steroids. He admitted to it, was disqualified, but it was all over the news.

• 6:53Speaker 05

  Rumors have persisted about Johnson, who set staggering records in the past 18 months. Now those rumors appear to be confirmed. The implications are enormous. It's a very sad day, you know, for athletics as a whole.

• 7:07Speaker 00

  So even back then, they knew testosterone could make someone a faster runner. That's why you weren't allowed to take it, right?

• 7:16Speaker 06

  It's funny, like, in the sports world, that was believed widely, so much so that the Olympic Committee was like, no, no, you can't take that, it's not fair. But in the science world, it was not yet widely accepted that this was even true. So Shalender brought up the case of Ben Johnson, because, you know, this was in the 80s, he was sort of beginning his career, and that made a big impression on him. Because that same year that Ben Johnson was disqualified for using a steroid, there was this paper that came out by a respected endocrinologist that said... There's no evidence that androgens have anabolic effects. They increase muscle mass, the strength of performance.

• 7:57Speaker 06

  The implication being that people who are abusing anabolic steroids are misguided. There were some studies that looked at this and found they often didn't really find an effect. But people in the, you know, the world of athletics, they would look at these studies and they'd be like, well, yeah, you didn't use a high enough dose. This is not the dose that we would expect people in the bodybuilding community, for example, to use.

• 8:21Speaker 00

  Uh-huh.

• 8:22Speaker 06

  So Shalender and some colleagues, they wanted to get to the bottom of this question. So they designed this great study. So they gave big doses of testosterone to healthy men. These were guys in their 20s and 30s, they got about 40 people. Some of them got testosterone, but some of them got placebo.

• 8:43Speaker 00

  Mm-hmm.

• 8:44Speaker 06

  And they also had some of the guys lift weights and some of the guys didn't do any exercise. This went on for 10 weeks. Meanwhile, they were like monitoring the guys' diets, making sure they were eating about the same number of calories, same protein. So it was, it was pretty thorough.

• 9:01Speaker 00

  Yeah.

• 9:01Speaker 06

  And they were checking to see at the end of the 10 weeks, did people's muscles get bigger? Could they lift more weight?

• 9:07Speaker 00

  Surely, it must work.

• 9:10Speaker 06

  Well, here's what happened.

• 9:12Speaker 00

  Okay.

• 9:13Speaker 06

  So first of all, everybody who weight trained saw an improvement. They got bigger and stronger. Not too surprising.

• 9:20Speaker 00

  Great, thank you.

• 9:22Speaker 06

  But the effect was a lot bigger for the guys on T versus the guys on placebo. So they had been doing stuff like squats with barbells. And at the end of the trial, they could squat, the guys on T could squat 40% more weight, while the guys on placebo, only 20% more.

• 9:36Speaker 00

  Yeah, that's right. I mean, you, I know it's so hard to know what's real and what's not, but you, there's a whole concept in weightlifting around whether you're juiced or whether you're natural. And you see these guys, and so clearly juiced up with testosterone.

• 9:53Speaker 06

  Yeah.

• 9:54Speaker 00

  If you were here to tell me that this is all placebo, I mean, like...

• 9:58Speaker 06

  That would be wild.

• 9:59Speaker 00

  Right, but okay, so it is real.

• 10:01Speaker 06

  It's real. And even the guys that didn't do any weightlifting, but were on T, saw gains. They, you know, they sat on their asses for 10 weeks but took T. They actually put on slightly more muscle than the guys who went to the gym and lifted weights but were on placebo.

• 10:19Speaker 00

  But were not, oh, not taking testosterone. Wow, that's how good it is.

• 10:23Speaker 06

  Which is totally unfair.

• 10:25Speaker 00

  Totally unfair. Mm-hmm.

• 10:27Speaker 06

  So Shalender and his team, they wrote all this up and put it in a paper. It was published in the New England Journal of Medicine, July 4th, 1996. And it... Immediately changed the academic view. After that, nobody has ever questioned this. Yeah, and since then, there have been plenty of other studies showing this and showing that you don't have to be a cis man for this to work. Researchers have also shown that adult women who take T will put on muscle as well as transgender men.

• 10:54Speaker 00

  And do we know exactly how it works? How is testosterone stimulating muscle growth?

• 11:01Speaker 06

  So we know that the testosterone will actually tell your stem cells to become muscle cells. And so that turns them into the fibers that make up your muscles. They literally get thicker because of this.

• 11:13Speaker 00

  That's crazy. It really does work, testosterone. Now, I'm guessing we're going to talk about the risks later in the show?

• 11:22Speaker 06

  No, that's the end of the episode, actually.

• 11:24Speaker 00

  Great, go for it. Live your dreams, hack your muscles.

• 11:27Speaker 06

  But yeah, but before we get to the risks, let's look at some of these other claims.

• 11:31Speaker 00

  Okay.

• 11:32Speaker 06

  So the next one I want to talk about is the idea of testosterone making you more aggressive. Because a lot of guys online, when they talk about this, they make it sound like you're going to go from like Keanu Reeves and Bill and Ted to Keanu Reeves and John Wick.

• 11:50Speaker 00

  I would say John Wick was fairly even keeled. I don't know, he was angry. If I were to get into the psychology of Keanu Reeves, but I.

• 12:02Speaker 06

  But he was an ass kicker.

• 12:04Speaker 00

  But he was an ass kicker, excellent, yes. And there was this concept of roid rage, right? This idea, you take a bunch of steroids, you get angry, you get mad.

• 12:13Speaker 06

  You get even.

• 12:14Speaker 00

  Yes. Is it true?

• 12:17Speaker 06

  I talked about this with Justin Coray. He is a social psychologist at Nipissing University in Ontario, Canada.

• 12:24Speaker 05

  This is a hot topic, hot topic in the US right now.

• 12:28Speaker 00

  Justin's watching the news. I like it. A scientist with a finger on the pulse.

• 12:31Speaker 06

  Yes, and actually, he's been studying testosterone and aggression for his whole career. And what he says is like, first of all, there's a lot of reason to think testosterone is tied to aggression. You know, think about males, male animals fighting for mates, like deer, you know, locking antlers, you can probably visualize that right now, very classic example. And that is testosterone fueled behavior. We know that because if you castrate those deer stags, I guess, they no longer do that. That's an experiment that's been done. And you know, when you castrate a male animal, you're basically taking away his testosterone.

• 13:10Speaker 00

  Yes.

• 13:11Speaker 06

  But the story of testosterone is a lot more complex than that, and that's especially true in people. And this is what Justin studies. So let me tell you how Justin studies aggression in the lab.

• 13:23Speaker 00

  Great.

• 13:24Speaker 06

  He has people play this game with this super fun sounding name.

• 13:30Speaker 05

  Point subtraction aggression paradigm. We don't tell them it's called that, but it's, we just tell them it's a computer game they're playing.

• 13:36Speaker 00

  Point subtraction aggression.

• 13:39Speaker 06

  Paradigm.

• 13:40Speaker 00

  Paradigm. Great.

• 13:43Speaker 06

  In terms of like how fun this game is, I would put it somewhere between like Pong and that test that they make you do at the eye doctor to check if you have glaucoma.

• 13:56Speaker 00

  Okay, okay. So we're a far cry from Zelda.

• 13:59Speaker 06

  Yeah.

• 14:00Speaker 00

  How does it work?

• 14:02Speaker 06

  So you get a keypad, it has a few buttons on it, and you've also got a computer screen. You're told to hit a button on your keypad 100 times. When you hit it 100 times, you get one point. And Justin gives people about 10 minutes to do this.

• 14:18Speaker 05

  So at the end of the 10 minutes, you're going to get paid based on how many points you got. So you get 50 cents a point. So if you get, you know, 20 points, you're getting 10 bucks, right?

• 14:28Speaker 00

  You press 100 times, you have 50 cents. Got it. Okay, so people.

• 14:32Speaker 06

  They want those 50 cents. So here's where the aggression part comes in. Justin tells you that you're competing against somebody else in another room. This is actually not true, it's just like the computer being random, but you're told that this person you're competing against can actually steal your points and thus your money and keep it for themselves. And you get a flash on the screen when that happens. You can take points away from that person, but you don't get to keep their points for yourself. So they can steal money from you, you can take away their money from them, but you don't get to keep their money. So it's like unfair, it's like a rigged game.

• 15:11Speaker 00

  Oh, it's just vindictive.

• 15:14Speaker 06

  Yes, exactly, exactly.

• 15:15Speaker 00

  Okay.

• 15:16Speaker 05

  So the only purpose of stealing points is to get revenge on the other guy. And in fact, you're wasting time hitting a button because you're not getting anything, you're not getting any financial or any points, you're not getting anything, any, any actual reward from it. The reward you're getting is an intrinsic reward of you got back at them, right?

• 15:35Speaker 06

  Why would somebody take points from the other player if they don't get the points added to their total?

• 15:41Speaker 05

  Because they're pissed off.

• 15:44Speaker 06

  Yeah, it sounds a little bit silly, but scientists have studied this a number of times and, and found this is a pretty good indicator of aggression. They've even found that in people who are violent in real life, when they take this test, they tend to score higher in terms of like all the revenge point hitting.

• 16:00Speaker 00

  Okay.

• 16:00Speaker 06

  Justin says he can even see this when he watches people play this game.

• 16:04Speaker 05

  They're like sitting back, they're hitting your buttons, like they're cool, right? Hitting their buttons, hitting their buttons. And then when they get stolen from them, like when you see them get provoked, they like lean forward and they start playing harder.

• 16:16Speaker 00

  All right, so now enter testosterone.

• 16:20Speaker 06

  The testosterone, yes. So Justin has done these studies where he gives people a dose of testosterone and sees what, does it make them play this game more aggressively? Or placebo? So he'll have some people get either testosterone or placebo and see what happens. Wendy, what is your prediction?

• 16:41Speaker 00

  You know, I guess based on everything we've heard about testosterone, one might expect that if you get a bump of testosterone, it would make you press the revenge button more often, right?

• 16:52Speaker 06

  You would think that. In reality, that's not true for everyone. So what Justin has found in, in multiple studies is that it does seem to make some people more aggressive if they've got certain personality traits. So he'll give these like personality tests and finds that for people who tend to be more impulsive and more dominant, they're more likely to get more aggressive with this testosterone bump. Here's how he put it.

• 17:22Speaker 05

  So if you are someone who is, likes to have power and influence over others, someone who's hyper competitive or someone who's, yeah, I won't even use any examples of people that I would think are high on dominance, but I think you get the point, right? So dominant men.

• 17:39Speaker 06

  Certain world leaders, perhaps?

• 17:40Speaker 05

  Right, right. I think probably all of them.

• 17:43Speaker 00

  Right, okay. You put them in this little lab, give them some extra testosterone, and it will do something to make them press that revenge button more often. But then if people had other personality traits, I guess lower on dominance, lower on aggression more generally.

• 18:02Speaker 06

  Didn't make a difference.

• 18:03Speaker 00

  It did not make a difference. This is for just cis men?

• 18:08Speaker 06

  I couldn't find any study on women that did exactly this, like tried to take into account personality traits. But there are studies looking at aggression and testosterone in women. It tends to be more true for men, that testosterone can increase aggression.

• 18:20Speaker 00

  For certain kinds of men.

• 18:22Speaker 06

  For certain kinds of men.

• 18:24Speaker 00

  This is interesting because I think in the data, researchers have also looked at this in trans men who take testosterone as gender affirming care. And in some of those men, you see an increase in aggression. And others, they didn't feel that at all.

• 18:43Speaker 06

  Yeah.

• 18:43Speaker 00

  So again, we see variation in the human spirit, which I guess isn't too surprising.

• 18:50Speaker 06

  Exactly. I mean, there was this other study that had guys take T and had them take journal, like write journal entries about how they were feeling and how their partners, their significant others also assess if they change, if their mood changed and found that like it didn't happen for everybody. But a couple of guys had bad reactions, like one guy had to even like leave the study because they were worried about them.

• 19:13Speaker 00

  And this is a study in cis guys.

• 19:15Speaker 06

  Yeah, yeah.

• 19:16Speaker 00

  So this idea of roid rage, it's not a complete myth. It does happen to some people. And that is probably what created this story that for everyone, you take testosterone, you'll get mad. But actually, it doesn't affect everyone in that way. And the science tells us that.

• 19:37Speaker 05

  When someone asks me, well, when you give testosterone, it's going to make everyone, it's going to make them aggressive. And I'm like, well, wait a minute, not everybody, not everybody.

• 19:45Speaker 00

  Up next, let's look at testosterone and sex drive.

• 19:49Speaker 06

  Yes, will it make you a total horn dog?

• 19:57Speaker 00

  Coming up.

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• 22:27Speaker 00

  Welcome back. Today, we're talking about testosterone. Senior producer Rose Rimler has promised to tell us whether taking a bit of tea can turn us into whore dogs. I would have said horn dogs.

• 22:42Speaker 06

  No, that's what I said. I said horn dog.

• 22:47Speaker 06

  I didn't say whore dog.

• 22:52Speaker 00

  All right. Either way, how does testosterone affect sex drive?

• 22:57Speaker 06

  Okay, Wendy, you need to hold your horn dogs.

• 23:00Speaker 00

  Okay.

• 23:00Speaker 06

  Just for a minute.

• 23:01Speaker 00

  Okay, okay, right.

• 23:03Speaker 06

  Before we dive into that, I just do want to say that, you know, one reason people are really concerned here is because of this idea that testosterone levels are going down in dudes.

• 23:14Speaker 07

  There's never been a worse time in modern history to be a young man hormonally. Testosterone levels are plummeting.

• 23:19Speaker 05

  A 25-year-old guy has the same testosterone levels his grandpa did at age 40.

• 23:24Speaker 04

  Which is a problem. It's a massive problem in men.

• 23:27Speaker 00

  Yes, yes, the so-called testosterone crisis.

• 23:30Speaker 06

  Yeah. So, for example, one study looked at testosterone levels of men between the ages of 15 and 39 in 1999 compared with men of that same age in 2015. And found that the modern dudes had about 25% less testosterone on average.

• 23:48Speaker 00

  25% less testosterone, same age group. Uh huh.

• 23:53Speaker 06

  Yeah, and other studies have shown, you know, different numbers, but similarly, like this decline.

• 23:58Speaker 00

  Interesting. So this, what's causing it? There's something in the water?

• 24:01Speaker 06

  I mean, a lot of people point to, you know, endocrine disrupting chemicals.

• 24:06Speaker 00

  The microplastics.

• 24:07Speaker 06

  Yeah, maybe stress, a more stressed out society, a more sedentary society. These have all been floated around. But the point, I think, for our conversation today is that with this sort of decline in testosterone levels broadly, it could be pushing more men into the too low category.

• 24:28Speaker 00

  And by too low, you mean when scientists study large groups of people and compare the health of a group of men, they find that there is a cutoff point where your testosterone is low and it starts to be associated with various health effects. Is that right?

• 24:47Speaker 06

  Right. I mean, the normal, healthy range of testosterone is pretty broad, actually. But down below a certain threshold, you can get symptoms like low energy, feeling down, getting crappy sleep, gaining weight, brain fog, and low libido. So the question is, if that's you, should you take tea?

• 25:05Speaker 00

  Right.

• 25:05Speaker 06

  Will it help? So the best study we have on this comes from this group of studies called the T Trials, led partly by our old friend Shalender Pazin. We heard from him earlier in the show. He and his colleagues in the 2000s, they enrolled this big group of older guys with low, clinically low testosterone, and they had them take either a testosterone gel or a placebo gel. They would rub it on their backs every day for a year. And they were tracking stuff like their sex life. How do you find out about that? You can't sit in the bedroom and take notes.

• 25:38Speaker 05

  So we had these diaries. So people jotted down for a whole week, all types of sexual activity, you know, whether they masturbated or partnered activity, or just whether they watched an X-rated video or Playboy magazine, et cetera.

• 25:53Speaker 00

  So cute that he says X-rated and not porn. Really dates the study.

• 26:00Speaker 06

  I guess they got a videocassette.

• 26:01Speaker 00

  Yeah, exactly. Went to the video store with the sticky floor. So what did he find?

• 26:08Speaker 05

  All types of activities were recorded. And those diaries showed clearly that the all types of sexual activities improved.

• 26:17Speaker 06

  So the guys in the testosterone arm at the end of the trial, about 20% of them reported that their libido was much better. And that's compared with less than 10% in the placebo group.

• 26:28Speaker 00

  Uh huh. Testosterone did improve when they had low testosterone, clinically low.

• 26:34Speaker 06

  And that, you know, really makes sense because we know that men who have severely low testosterone, like guys with Kleinfelter syndrome, that's where you're born XXY instead of XY, they make very little testosterone. One of the symptoms of that syndrome is a very low or nonexistent sex drive. We also know that trans men often report a boost in their sex drive when they start taking tea, at least at first. It tends to settle down over time. So it totally makes sense.

• 27:03Speaker 00

  Yeah, so I think that the take home is really if you have clinically low levels of testosterone, taking more to get you into that healthy range can boost your sex drive. But if you are already in the healthy range, and like you mentioned, guys in the healthy range of testosterone, some have higher, some have lower, all in the healthy range. And we know from study after study after study that when you ask those guys in the healthy range, how often do you think about sex? How often are you having sex? How often are you watching X-rated videos? And then you test their testosterone, having a little bit more or a little bit less actually

• 27:47Speaker 00

  isn't correlated with a higher sex drive.

• 27:49Speaker 06

  That's right. Yeah, that's another really good clue, that if you're in the normal testosterone range, it doesn't really matter. And this brings us to our next question, which is, does testosterone help women with their sex drive? So some of our best data on like women and testosterone and sex drive come from East Germany, back before the collapse of the Soviet Union. So back then, the state was actually giving their athletes steroids in order to win more Olympic medals. And they were giving their female athletes especially high doses of something called terabinal and documenting the effects. And those documents became available, you know, later on.

• 28:28Speaker 00

  Right.

• 28:29Speaker 06

  And they show that women getting these big doses of testosterone, essentially, got super horny. In fact, some women reported that this was unbearable and asked to quit sports rather than keep taking it.

• 28:46Speaker 00

  Wow.

• 28:48Speaker 06

  I know. And a more modern survey of female users of anabolic steroids that I found, surveyed them and asked them about their sex drive. And a lot of them said the same thing, that it really made their sex drive go up, but they didn't necessarily like it all that much.

• 29:03Speaker 00

  Hmm. Now, both, I mean, I don't think we want to call what happened in East Germany a study, but in both cases, there's no placebo control.

• 29:12Speaker 06

  No. And, I mean, these are high doses, though. Like, we're talking about doses where you can grow more body hair, your voice can deepen, you can get enlargement of the clitoris. The doses that I think most of the influencers are talking about when they're like, you're a woman with low sex drive, you should get on testosterone, they're much lower. And we do have a placebo-controlled trial to talk about when it comes to that.

• 29:38Speaker 00

  Okay.

• 29:39Speaker 06

  There's a drug company that tested this. They had women who said that they had a distressingly low libido, randomized them to wear either a testosterone patch or a placebo patch for a year. These are all post-menopausal women. The women who wore the testosterone patch reported about one more satisfying sexual experience per month.

• 30:00Speaker 00

  Okay, one more sexually satisfying experience per month, I guess, not kicking that out of bed. I don't even sure. No miracles, but can help. But could help. All right.

• 30:11Speaker 06

  And just quickly, one final thing I want to look at, one final claim that I see everywhere, is this idea that taking testosterone will like put a lot more pep back in your step, give you a lot more energy.

• 30:22Speaker 00

  Yes.

• 30:23Speaker 06

  So this is another thing that Shalender and his team looked at in the T Trials.

• 30:27Speaker 00

  Mm hmm.

• 30:28Speaker 06

  People's energy. And other studies have looked at this as well. And the result is always kind of like sad trombone, you know?

• 30:38Speaker 00

  Oh. Oh. In what way? Put some numbers behind our sad trombone.

• 30:44Speaker 06

  For example, in the, in the T Trials, the team measured what they called vitality by giving guys a questionnaire that asked them stuff like, how tired did they feel? How functional were they day to day? A max score on this questionnaire would be 108 points. And the team decided before the study that a meaningful effect would be an improvement of four points.

• 31:07Speaker 00

  Okay.

• 31:08Speaker 06

  It didn't clear that hurdle. They saw a little bit of improvement, but the effect was really small. And Shalender said that surprises him because when he treats patients with low T, he said, and gives them, you know, testosterone supplementation, he says they often tell them that they feel more energetic after they start therapy.

• 31:26Speaker 05

  And, you know, I've been the author on many of these studies, and I'm always surprised by such a small effect.

• 31:34Speaker 06

  Yeah, it's very underwhelming.

• 31:35Speaker 05

  Very underwhelming, isn't it?

• 31:37Speaker 00

  Well, the placebo is a wonderful thing, right?

• 31:41Speaker 06

  Mm-hmm. Yeah, for all kinds of people, for all kinds of things. You hear like, it's basically gonna cure everything that's wrong with you. And you know, we hear about it so much for menopause symptoms. This is something that came up a lot, like your brain fog and you know, your focus and all that. We don't actually have any research to back that up, but we do have our studies that don't have control groups and you really need one because of the placebo effect from testosterone. Or they're funded by some clinic that's shilling testosterone.

• 32:08Speaker 00

  This is what you're finding in the, in the, in the post-menopausal research space.

• 32:12Speaker 06

  That's right.

• 32:14Speaker 00

  So then what are the risks? What are the risks? Is it time to get to the risks? You've mentioned your clitoris might enlarge. Where, what else could happen?

• 32:23Speaker 06

  Um, so in, in people who have testicles, if you take testosterone, you know, give yourself a big dose of testosterone, you know, chronically, you take it all the time, your brain is gonna sense that you have plenty of testosterone and it'll stop making your own testosterone. It'll stop the homegrown stuff. And that brings us to our biggest, most obvious risk, and that's infertility.

• 32:46Speaker 00

  Mm-hmm.

• 32:47Speaker 06

  The reason that leads to infertility is that in order to make viable sperm, you need testosterone to be coming from the testes. And that's not gonna happen if you've turned off the tap that comes from your brain.

• 32:58Speaker 00

  Mm-hmm. And people think testosterone equals masculinity, equals high sperm count. Actually, exact opposite, the exact opposite. You're taking testosterone can lower your, your sperm count to the point where you are infertile. Right?

• 33:17Speaker 06

  Yes. And this whole thing about sperm and about shutting off your own testosterone, it's not trivial and it's not necessarily super short term. Uh, I talked about this with, uh, Richard Aukas. He is an endocrinologist and professor at the University of Michigan. And this actually came up when we were talking about this idea of supplementing soldiers with testosterone.

• 33:37Speaker 01

  But you know, if you're taking testosterone, you probably shouldn't be on the front lines fighting. Right?

• 33:42Speaker 06

  Why is that?

• 33:43Speaker 01

  Well, what if you get captured? Right? Because remember, taking testosterone, you're going to then become dependent on it. You're gonna suppress your own production and then, uh, you're gonna have to take that for the rest of your life. So if you get captured and you don't have access to your testosterone, then you're gonna be even lower than you were before you got treated.

• 34:05Speaker 06

  That's permanent?

• 34:06Speaker 01

  Uh, well, I mean, it depends how long you use it.

• 34:10Speaker 00

  Yeah, wait, it doesn't, the moment you stop taking your testosterone supplements, your body forgets that it's gotta go up again?

• 34:20Speaker 06

  Well, it depends on how long you've been on the testosterone supplements. It depends on how much you've been taking. Um, but it can take a while to come back online and it can be permanently suppressed, even when it does come back online, including your sperm counts.

• 34:36Speaker 00

  Wow. That's a huge, that's a huge risk.

• 34:41Speaker 06

  It's a huge risk. And especially when I think about like teenagers taking this stuff, like, oh my God. But yeah, I mean, also you can actually go through withdrawal after stopping testosterone replacement therapy or stopping, you know, steroids. Um, you can get symptoms like headache, fatigue, restlessness, insomnia, feeling sad, low sex drive, all this stuff that you're supposedly trying to avoid by taking T can actually end up getting worse after you stop the testosterone therapy.

• 35:08Speaker 00

  Mm-hmm. And then what about other effects to your heart? To your, the, the rest of your body if, while you're taking the testosterone?

• 35:18Speaker 06

  Yeah. So people will talk about acne, that comes up, uh, breast tenderness. Um, and also if you are someone who is capable of becoming pregnant, you get pregnant while you're on testosterone, it could harm the fetus. It's another big thing to think about. Um, when it comes to stuff like your heart, your prostate, if you have one, there has been a lot of concern that testosterone, taking it could, could be, um, bad, like give you heart attacks or prostate cancer. But we do have a, a study a drug company did a few years ago that found no difference in heart attacks or prostate cancer for guys taking moderate doses of testosterone compared with a placebo over four years, which is somewhat reassuring.

• 35:58Speaker 00

  Okay, yeah.

• 35:59Speaker 06

  But it might be a different story with much higher doses. So researchers have seen damage to people's hearts and even brains after they've been juicing for a while. So there are certainly downsides.

• 36:11Speaker 00

  Okay.

• 36:11Speaker 06

  Um, so I think that can be really downplayed by people who promote this stuff.

• 36:16Speaker 00

  For sure.

• 36:17Speaker 06

  And it doesn't help that a lot of the information we get about taking testosterone is coming from people who are selling it.

• 36:24Speaker 00

  Mm-hmm.

• 36:25Speaker 06

  A lot of experts have pointed out that this craze for testosterone really took off around the year 2000, which was about the time that drug companies figured out how to put it in a gel.

• 36:36Speaker 00

  Mm-hmm.

• 36:37Speaker 06

  And so you didn't have to just inject it. So that this new product that would be a lot more, um, you know, appealing to a lot more people.

• 36:45Speaker 00

  Right.

• 36:46Speaker 06

  Yeah. And so there's been a ton of advertising since then to people and to doctors.

• 36:51Speaker 00

  Yes. And now the advertising is coming through your favorite influencer and their favorite affiliate code.

• 36:57Speaker 06

  Mm-hmm, yeah.

• 36:59Speaker 00

  Right.

• 37:01Speaker 06

  So there's this push by pharma companies, and I think it's dovetailing with this other social change we're seeing. Uh, we're gonna go back to the guys now. A lot of researchers argue that we've actually seen a shift in what the ideal male body is supposed to look like.

• 37:16Speaker 00

  Oh, for sure.

• 37:17Speaker 06

  Over the last few decades. Um, so they've done stuff like they've taken action figures of today and compared them with action figures of the past. And they found that toy makers are actually making them like buffer.

• 37:30Speaker 00

  Yeah. I mean, even if you look at He-Man, He-Man is, probably looks like a twink these days. Right? There's not even a vein in sight, you know?

• 37:42Speaker 06

  Yeah, yeah. Yeah, it's crazy.

• 37:45Speaker 00

  That's crazy.

• 37:46Speaker 06

  It's crazy. They've also compared centerfolds in Playgirl magazines, uh, over the years and found that the male models featured there, they're getting more muscular.

• 37:54Speaker 00

  For sure, for sure. These, online, you scroll and these huge guys, you don't look that huge anymore. They, that looks like that's what a normal guy is supposed to be. And that, whereas in the past, you, you'd think, whoa, that's a bodybuilder.

• 38:13Speaker 06

  Yeah. And this is something that Schaller really cares about and brought up and talked to me about. Um, cause he, he thinks what's going on here is we're getting this like obsession with this very narrow and unrealistic idea of what masculinity is.

• 38:29Speaker 02

  What it means to be a man, a successful man, a good man.

• 38:33Speaker 06

  I've seen some, uh, young men on social media talking about trying to get high T. They're perfectly healthy, but like, I wanna be high T. Maybe they take T or maybe they're just trying to boost their T in other ways. But they really are fixated on their testosterone. And sometimes I think like, I feel like you need an older, wise, knowledgeable man to give you some advice. So I'm thinking you would be a great person. So if you could give some advice to these, these guys, these young guys, what would you say to them?

• 39:01Speaker 02

  I would put my hands on them, hug them and tell them, you have such a perfect, beautiful body. It is so perfect. It's beautiful in its perfection. You don't need testosterone to be happy or healthy or have a sense of well-being, right? And, and so I think, I think these young men are struggling and, and they just need a hug and, and some reassurance that they are beautiful, their bodies are perfect. And testosterone isn't gonna make them happier, more successful.

• 39:39Speaker 00

  That's Science Versus.

• 39:42Speaker 00

  How many citations are in this week's episode, Rose Rimler?

• 39:44Speaker 06

  This week we have 83 citations.

• 39:48Speaker 00

  And if people wanna see them, where should they go?

• 39:49Speaker 06

  They can click on the link to our transcript and they'll find that link in our show notes.

• 39:55Speaker 00

  And if you have someone in your life that needs a hug, that needs to know how beautiful their body is, share them this episode. If they don't need testosterone, they need science. Thanks, Rose.

• 40:06Speaker 06

  Thanks, Wendy.

• 40:08Speaker 00

  Oh, and finally, if you are still thinking about the fact that children's toys have been getting more and more muscly, not to mention, of course, these images that we're seeing online, just super, super muscly men. Well, I had this amazing chat this week with the science educators behind ASAP Science, Mitch Moffett and Greg Brown. And we were talking about this growing mental health condition called bigorexia. And it really made me question my own habits at the gym. I think it's a really fascinating conversation. It's out now, it's on YouTube, we're gonna put a link in the show notes. So please go check it out. And Mitch and Greg have their own podcast, it's called Side Note. That is where I first heard about this condition, bigorexia. So you should totally go check it out.

• 40:54Speaker 00

  This episode was produced by Rose Rimler with help from Merrill Hawn, Akati Foster Keys, and Michelle Dang. We're edited by Blythe Terrell. Wendy Zukerman, me, is the executive producer. Fact checking by Marlo Starling. Video editing and sound by Bobby Lord. Music written by Bumi Hidaka, Peter Leonard, Emma Munga, and Bobby Lord. Thanks to the researchers we spoke to for this episode, including Dr. Kathleen Casto, Dr. Carol Hooven, Professor Ruth Wood, Dr. Stephanie Page, Professor Sari Van Anders, Dr. Adam Stanaland, and Professor Anthony Hackney. Thanks to Humdinger Studios in Melbourne and Wolf Island Studios in New York City. Science Versus is a Spotify Studios original. Listen to us for free on Spotify or wherever you get your podcasts.

• 41:37Speaker 00

  We're on YouTube, we're on TikTok, we're on Instagram as well. Come and say hello. I'm Wendy Zukerman, back to you next time.

• 41:52Speaker 06

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