Why Men’s Testosterone Levels Are Plummeting - Dr Shanna Swan

Dr. Shanna Swan is a Professor at the Icahn School of Medicine at Mount Sinai, an environmental and reproductive epidemiologist and an author. Many of us have heard about about harmful chemicals in plastics, food and water that can mess with our hormones. But just how much truth is in this? How much of our health is disrupted by our modern environment? Expect to learn what is happening to male and female reproductive health, how important testosterone is for everyone, the problems with male fertility rates and sperm count, the chemicals that are most impacting reproductive health, what men can do to improve and increase their sperm count, how to limit your exposure to bad chemicals much more... - 00:00 What’s Happening to Men’s Testosterone Levels? 03:40 How Important is Testosterone? 09:45 Why This Negatively Affects Both Partners 17:03 Link Between Testosterone & Sperm Count 19:04 Statistics on Sperm Count Over Time 24:09 The Social Impact of Lower Fertility 33:58 Using Chemicals to Alter Hormones 42:35 How a Mother’s Food Impacts Her Baby 48:28 Lifestyle Changes to Avoid Toxicity 57:15 Effectiveness of Reverse Osmosis Filters 1:00:19 How Bad Chemicals Impact Behaviour 1:10:35 Men & Women’s Reproductive Success As They Age 1:13:28 Future of Fertility in Humanity 1:22:03 Where to Find Shanna - Get access to every episode 10 hours before YouTube by subscribing for free on Spotify - https://spoti.fi/2LSimPn or Apple Podcasts - https://apple.co/2MNqIgw Get my free Reading List of 100 life-changing books here - https://chriswillx.com/books/ Try my productivity energy drink Neutonic here - https://neutonic.com/modernwisdom - Get in touch in the comments below or head to... Instagram: https://www.instagram.com/chriswillx Twitter: https://www.twitter.com/chriswillx Email: https://chriswillx.com/contact/

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Chris Williamson?

  What's happening to testosterone levels in men?

• 0:04Speaker 01

  So that's a great question. And actually, I work with a research group and have been for quite a long time now, since,

• 0:12Speaker 01

  you know, 10 years, looking at trends. And, and the trend we're looking at right now is testosterone. And it's difficult. We haven't finished it. We're in the midst of it. Maybe I'll come back and talk to you when we get the results. But there are a number of papers published that we think are pretty authoritative that talk about declining testosterone. But the, the other thing that we can look at, which is different from doing a literature review, you can say, well, how is it clinically? And there's a lot of data showing that the use of testosterone, particularly by young men, has been climbing, alarmingly, actually. So

• 0:59Speaker 01

  from a lot of measures, we have hints that testosterone is declining. That's a long way from saying what we said with sperm count, you know, worldwide, we see a decline. And we'll come back to that, I'm sure. We can't say that about testosterone at this point. But we can say there are a lot of signals suggesting that testosterone is in trouble.

• 1:22Chris Williamson?

  Yeah, obviously, one of the challenges we have here is are young men taking testosterone because they're suffering with the effects of low T, erectile dysfunction, low energy, low mood, et cetera, et cetera. Or is it because of increases in body dysmorphia or unrealistic representations of, of men in media and they feel like they need to use testosterone as a performance enhancer to become more masculine or to become more muscular and stuff? Why is it the case that you have more verifiable data around sperm count than you do around testosterone levels? I would have thought that testosterone levels would have been more widely available. I know more guys that know their testosterone count than know their sperm count.

• 2:05Speaker 01

  That's a good, good point. That's today and probably in the US. But

• 2:13Speaker 01

  Sperm count has been understudy for uh sixty five years. So there's a, there's a long history of studying sperm count. And there's been very little on testosterone. Um, so I can't tell you why that is. I mean, men give a sperm sample for a number of reasons, not just research, right? They give it for pre vasectomy. They give it um because they want to be tested for possible infertility. They give it for a lot of reasons, and I think it's much more

• 2:56Speaker 01

  common uh giving a testosterone, a blood sample, which you have to give for testosterone is um, I think, less. I know it's less widespread because there's much less literature on it. And when scientists Yeah.

• 3:12Chris Williamson?

  It's so interesting to me, you know, I again, uh, maybe again, you're probably right. This is my not only weird bias, but also my Austin podcast bro biohacker world bias coming into play. Where all of my friends know that they're at seven fifty five nanog- nanograms per deciliter. And and they're gonna try and get up to nine hundred because of blah, blah, blah. Uh, I don't know who knows their sperm count. Um, just before we get on to sperm count, tell me from the testosterone, it seems there are some sort of, I guess, uh, rough hewn signals that indicate the testosterone is going down. Um, how important is testosterone?

• 3:54Chris Williamson?

  You know, there is a uh somewhat in the media of a demonization in some ways of of testosterone in men or some of the activities, I suppose, of, you know, high testosterone men. Um, how important is testosterone to function for men, for longevity, for health, for reproduction? What does it do in your world?

• 4:14Speaker 01

  Absolutely, absolutely critical for many, many things. And I would start with the testosterone in the developing fetus. So the first time the testosterone matters a lot is in the first part of the first trimester. That's how early it is. And and it turns out that, okay, so let me back off. Okay.

• 4:39Speaker 01

  At the beginning of pregnancy, as soon as you can measure anything or see anything, you will see a genital ridge in males and females. That's the genital tract, but it not different in males and females. It's just this ridge, right? And then, at the right time, and we're not sure exactly of that time. We know it in rodents, and rodents, it's day 18 to 21. But in humans, not so much. We know that it's an early first trimester. At that time, genetically programmed, if it's a genetic male, programming will start the production of testosterone by the testes, formation of the testes, then testosterone gets produced.

• 5:23Speaker 01

  And that testosterone is what kicks off the genetic male differentiating himself from the genetic female. Up until that point, it's all the same. And in fact, if the testosterone is not there at the right time or at the right amount, then that male will not proceed on the path to a male typical genital. He will, he might have smaller testicles, smaller penis, small, less descended testicles. And then, my favorite is the anal genital distance, which we should talk about for sure.

• 6:01Chris Williamson?

  So glad that's, I'm so glad that's your favorite. I was waiting for you to bring it up.

• 6:08Speaker 01

  Well, the reason it's my favorite is because until I started looking at it, it had only been looked at in animals. Nobody thought anything about AGD, anal genital distance. It was not considered interesting for humans. And then I showed it was, yes, extremely interesting for humans. And, and you know, so the, the first thing, talk about this differentiation, when you start out, everybody has the same AGD.

• 6:38Speaker 01

  Length works. And then as the testosterone comes in, the AGD in the male gets longer, longer, until it's about, you know, twice as long as the female or something like that. It's markedly longer. If that doesn't happen, then it's still a male, but he's a incompletely masculinized male. So, so this measure is, you know, really, really critical. Um,

• 7:08Speaker 01

  so, and other things happen. The testes don't descend into the scronum and the penis is actually smaller, which a lot of people get upset about and other things.

• 7:22Speaker 01

  So, so that, you know, fulfilling that potential of a male typical genital requires, you said, is it important? I would say most men would say that's pretty important.

• 7:34Chris Williamson?

  Yes. Okay. Roll me forward because what we're talking about there presumably is

• 7:41Chris Williamson?

  endocrine disruption in the mother, which impacts the growing fetus natively. What about when a mother and son are no longer attached? What, how important is testosterone for development as we move into adulthood?

• 8:00Speaker 01

  Yeah. So,

• 8:03Speaker 01

  the testosterone is important at many stages. It's important for puberty. It's important for other markers of male development. And one of the things that's really key is it's important for libido.

• 8:20Speaker 01

  So, and by the way, it's not just the male. I just want to put in a little word for the female here. So,

• 8:29Speaker 01

  We'll talk about chemicals that influence testosterone. And I'll just say that a class that I've studied is the class of chemicals that make plastics soft. That's the phthalates. Now, when the mother, or just a woman, she doesn't have to be a mother, is exposed to less, well, actually more phthalates, then she is less satisfied sexually. So we found that out by asking women. We said, how satisfied are you with your sex life? How often do you have sex? That was in our study. We asked them that. And we got their urine, and in the urine, we measured their phthalates. And it turned out that when the woman had low phthalates,

• 9:13Speaker 01

  she was less satisfied and she had sex less often.

• 9:17Chris Williamson?

  What does low phthalates relate to from a testosterone in female perspective?

• 9:23Speaker 01

  In both males and females, phthalates lower testosterone.

• 9:28Chris Williamson?

  Hang on, but you said low phthalates mean low testosterone? Would it not be high phthalates would mean low testosterone?

• 9:33Speaker 01

  I meant to say low phthalates, low testosterone, right. Phthalates come in, testosterone goes down.

• 9:39Chris Williamson?

  Understood. High phthalates, low testosterone in both men and women. Okay, presumably, this is a double edged sword. If women who are high in phthalates, lower in testosterone, sexual, less sexual satisfaction, and also the men who are lower in testosterone have lower libido, probably lower erection quality and stuff like that. So you have an environment, an endocrine environment here, which is reducing sexual satisfaction for both partners and their ability to satisfy each other as well.

• 10:17Speaker 01

  Correct. And I do not have evidence.

• 10:22Speaker 01

  Firm evidence of this. However, you probably know that fertility rates worldwide are down, and in particular in East Asia, they are absolutely at the bottom. And one of the things that's happening is that people are not having sex. They are not marrying, they're not coupling, they're not having sex. Okay. And the government is trying to pay people to turn this around. It's, it's really serious. Now, no one has linked that specifically to an endocrine disrupting chemical, but I cannot believe, given what we know about the action of these chemicals, that it is not playing a role.

• 11:05Chris Williamson?

  So I've had a lot of

• 11:07Speaker 01

  Yeah.

• 11:08Chris Williamson?

  Go ahead.

• 11:09Speaker 01

  I was just gonna say, but in Japan, there is a, two phenomena I want to mention. One is called rent a family, where if you haven't, yeah, you can rent, that's, you can sign on to rent a family to get a child for a party or a spouse for a party.

• 11:28Chris Williamson?

  Oh my God.

• 11:29Speaker 01

  Right? And the other one is a phenomenon of Japanese women marrying themselves. And that is the weirdest thing to me, that, and you can go online and look for that, there are women who have ceremonies at which they marry themselves. So to me, this is one of the clearest indications of a lack of libido. Very strange. Yes.

• 11:57Chris Williamson?

  Solo weddings, Japan solo weddings for single women. Self marriage has become increasingly popular in the 21st century, especially among affluent women. As of 2014, a travel agency in Kyoto is offering self marriage packages for women, with some customers being wives who were dissatisfied with their original wedding. Wow. I mean, that's even worse than being left for the guy next door. Being left for yourself is, is a, a, a real tough pill to swallow. So yeah, I mean, look, I've had a lot of conversations on the show about declining birth rates, something I'm increasingly concerned about. But Dr. Stephen Shaw on the show, who I think is probably the best population demographer when it comes to birth rates at the moment, he did an amazing documentary called Birth Gap. And I agree.

• 12:41Chris Williamson?

  Me and my evolution-pilled buddies, a lot of the time, we're talking about the mating crisis, we're talking about issues with women finding a man that they're attracted to, hypergamy, more distractions from screens, you know, just more life options that people have, delayed adolescence pushing people's lives a little bit further, all of these, and they're all, you know, socials, psychology slash evolutionary explanations that come into attraction. But if we just straight up say libido's lower, like if we just have that, just this one factor, libido gets reduced, we don't know by how much, maybe it's by 10%, maybe it's by 50%, we don't know, but people are just less bothered about being

• 13:24Chris Williamson?

  sexually active with, with, and like just that on its own, that is fundamentally the driver. And people can reverse engineer, you, I'm sure that you'll be familiar with the difference between proximate and ultimate explanations for behavior. So the proximate explanation for, for having sex is sex feels good. The ultimate explanation for having sex is that it makes babies. Now, what we're looking at a good bit of the time, I think, in my world, and this is something that's maybe an error that I need to bring up with the guys, we're looking at the ultimate explanation. A lot of the time, we're thinking, well, people are kind of reasoning themselves, it's a very cerebral cognitive kind of like right brain approach to, people are reasoning themselves into having kids or reasoning

• 14:08Chris Williamson?

  themselves out of having kids, they've got other things to do. But if you just look way closer to home, sex is just less of a driver, potentially due to reduced libido, reduced testosterone in both men and women. And that means that people are just not so fussed about getting into bed with each other. You know, I remember when I was at, when I was at university 15 years ago, that started at university.

• 14:33Chris Williamson?

  Oh God, 18 years ago now. And when I went there, it was still this sort of very driven, Larry Laut sort of British culture and you know, all of, whereas now, I think 50% of men aged 18 to 30 aren't looking for long-term or casual relationships. To me, a man who went through that period of my life, no, the reality distorting power of the male sex drive in that age bracket is, is a sight to behold. You know, it's very powerful. So yes, absolutely. I think that that, that base rate should be factored in. How can testosterone just impact our desire to have sex? And then downstream from that, the babies, the marriage, the, all the rest of the stuff. Like, if you're the sort of person that wants to have sex once a year, or the sort

• 15:17Chris Williamson?

  of person that wants to have sex once a week, your desire, your motivation to go out and get a partner is going to be really different.

• 15:24Speaker 01

  Yeah, yeah. I wanted to mention, you, you mentioned briefly, uh, the effect of testosterone over your lifespan. And, and I do want to say that there's now, and there was just a new study out about this. Um, we have increasing evidence that men with low sperm count, men and women who are infertile, have a shorter lifespan. It's really pretty, now it's been shown enough times, you know, in Denmark, by Mike Eisenberg in Stanford, um, that I think there's probably a half a dozen papers on this. And it's really a lot. And I mean, first of all, men and women

• 16:08Speaker 01

  who have impaired, I would say hormone systems, uh, are more likely to have other medical problems. Uh, for example, heart disease is increased. Um, diabetes is increased, reproductive cancers are increased. What this adds up to is you die earlier. So here's something that you are exposed to pre-aidally, and then again, in adult life, of course, or in adolescence, we can talk about when the exposures are important. But throughout your lifespan, particularly early in life, you're setting up, you're setting up your health for the rest of your life.

• 16:54Speaker 01

  Exposures during pregnancy are most important for your whole life's health.

• 17:00Chris Williamson?

  Hmm.

• 17:00Speaker 01

  Because everything's developing then, right?

• 17:03Chris Williamson?

  What is the relationship between testosterone and sperm count for men?

• 17:09Speaker 01

  Ah, well, if you don't, it's complicated. Men who who use testosterone supplementation do not produce sperm. I get, do you know that?

• 17:21Chris Williamson?

  Of course.

• 17:22Speaker 01

  Yeah, you do.

• 17:23Chris Williamson?

  Well, I mean, I say, of course, like everyone does, but I think a lot of people think that going on TRT will somehow increase your sperm quality or increase fertility, but it doesn't.

• 17:33Speaker 01

  The opposite, the opposite. However, for the maintenance of the system, you need adequate testosterone. So at an ongoing basis,

• 17:45Speaker 01

  for the system to work properly, and it's not just directly testosterone and sperm, it's you, you need adequate testosterone. So interfering with that is going to mess up your brain and mess up, you know, the production of sperm, mess up whatever, the whole, the whole gamut.

• 18:05Chris Williamson?

  Presumably low. So am I right in thinking there must be a U shaped curve to testosterone and sperm quality, that too low testosterone in men? Or is it just a linear line? The lower the testosterone, the more sperm? Because obviously too much, which is the exogenous stuff, that decreases sperm count.

• 18:24Speaker 01

  No.

• 18:24Chris Williamson?

  But what about too little?

• 18:26Speaker 01

  Yeah. So that when you're taking testosterone, your body gets the everything, all of these hormones work on feedback. Feedback loops. And so if you give the message, wait, I got enough of this stuff. You don't need to make this.

• 18:40Speaker 01

  Your own testosterone production will be cut down and your production of sperm will be cut down. So it's, it's complicated. And I'm not an andrologist, so I can't really speak knowledgeably about this, but I can tell you what we observe that, you know, that when men go, as you know, men go on testosterone, they stop producing sperm. Yeah.

• 19:01Chris Williamson?

  All right. So moving on to the big one, sperm count. What is, what are the statistics, the trajectory of sperm count over the last 65 years?

• 19:13Speaker 01

  Right. So until so many people have looked at this and we looked at this, I would say arguably better than anyone because we used techniques that were not available in the past and we we used something called a meta-analysis and we did a very deep dive on the whole world's literature, looking at sperm count. And I'll tell you the conclusion and then we can talk about what went into that. The conclusion was that sperm counts are going down at about 1% per year and they're not stopping. It's consistent. It's now we know from recent studies that we've

• 19:56Speaker 01

  done is actually worldwide and and it's increasing in fact that the in our most recent study,

• 20:06Speaker 01

  the rate of decline was 2% per year after 2000, 2% per year, which is huge. Okay? So we published that in 2022. So after 2000, if you go all the way back till 1973 and look at the whole spread, it's over 1% a year. So that's tells you that things are not getting better.

• 20:32Chris Williamson?

  They're getting worse. It's increasingly decreasing.

• 20:35Speaker 01

  That's right. Increasingly decreasing. That's kind of weird, but there it is. Yeah. Um, the other thing we found in our update was it actually does seem to be worldwide. In our initial analysis, we had to take the data. We always have to take the data that's available. Can't make it up, right? And and and the publications in the non-Western countries were very few. So there was not very much data from Asia and Africa and South America. But in our 2022 paper, there was much more. And I think what happened was when our paper came out in 2017, which was kind of a big thing, a lot of people started saying, wait, what about what about us?

• 21:18Speaker 01

  And started looking in these other countries and toss that in and then we saw that it was worldwide. So our conclusion of that 2022 paper was sperm count is declining worldwide and the rate of the decline is increasing.

• 21:34Chris Williamson?

  Have you got any idea what countries are having this decrease at a slower rate? Are there any blue zone equivalents for sperm?

• 21:49Speaker 01

  That's a great question.

• 21:51Speaker 01

  I don't think we know enough to generalize, but I will say that in Denmark, the rate of decline has seems to have leveled up. That's one of the best studied countries because a lot of the work was done there. Originally, the first sperm decline paper came out of there and a lot of work. They're excellent and and they've been following military recruits, men, you know, young men coming into the military and asking them if they have a semen sample. They've been doing that for a long time. And what they're seeing now is that it doesn't seem to be getting worse. So I would say if we had to find one place that seems to be doing better, I would say is Denmark. They're still not doing great.

• 22:35Speaker 01

  They still have a lot of men with very low sperm count. Nevertheless, now Finland, on the other hand, which,

• 22:43Speaker 01

  you know, used to be much better than Denmark is now going down to meet Denmark. So that's confusing because they're very similar. You know, demographically, they're not that different. Their exposures are probably not that different. So that's a conundrum that we have to to deal with.

• 23:01Chris Williamson?

  I'm fascinated by trying to map this because obviously if you could look at fertility rates, marriage rates, if you could do some self-report studies of how much do you desire sex? How often do you want to have sex? How often do you have sex? You know, you could, I guess, do surveys as well about people's beliefs and desires to get into relationships and stuff like that. I would love to map and then and then look at what is very prevalent in the water. What are the sort of packagings that are used? What's the type of consumption, et cetera? I would be fascinated to see how much of this Asian downturn in birth rates can be seen as.

• 23:46Chris Williamson?

  There is a particular brand of plastic that is exclusively used to package all meats and vegetables, and it only exists in Finland. It recently got introduced to Finland, and it has been in fucking South Korea or whatever for ages.

• 24:00Speaker 01

  Yeah, yeah, yeah. I share that wish with you, but I don't think we're going to find that. Let me, let's just talk about social factors, since you kind of brought those up. So, and we haven't, I haven't said, but I'm sure you know, you've had a fertility expert on, a demographer on, excellent person. So you know that the fertility rate, which is the number of children that a couple can expect to have in their lifetime, that fertility rate, which should be 2.1 to maintain the species, is now going down almost all over

• 24:41Speaker 01

  the world. And I'll give you the exception, but almost all over the world. It's including African countries, which had a very high fertility rate. Okay. In East Asia, so we want to aim for 2.1, okay? 2.1 maintains the status quo. In South Korea, at last look, it was 0.8. Right? It's also like, I think 0.9 in Japan. It's, those East Asian countries are very, very low.

• 25:14Chris Williamson?

  Germany, also not, not good at all.

• 25:17Speaker 01

  Not good at all, if you want to maintain the population. And, and the governments are trying a lot economically to, to pay couples, to get married, to have children, to get your, you know, you get a tax credit for the child, you get.

• 25:33Chris Williamson?

  Hungary did that thing where the, the woman got, I think for three kids, didn't pay tax for the rest of her life.

• 25:40Speaker 01

  Yeah, right. So, but it's not working. It's not turning that around. And, and so there's something else going on here, you see? And, and, and so that's what we as a society have to, to think about if we want to maintain our.

• 26:01Speaker 01

  Existence? I mean, there are endangered species and, and, and the, and then humans do fulfill-

• 26:08Chris Williamson?

  We are one of them.

• 26:09Speaker 01

  Yeah, so, so, um, but let me say, I'm not saying it's all chemicals. Okay, I want to make that clear. I think the chemicals that affect our bodies hormones are extremely important in this story, but they're not the whole story. So, so here's a couple of things that lower sperm count, that you can control. Good to know, right? You can, your diet, you mentioned the blue zones. Uh, be interesting to see the fertility in the blue zones and the sperm count and so on. I, I don't think that, uh, Dan has done that, Dan Buettner. But, um, the, um, we did a study with Harvard on, um,

• 26:51Speaker 01

  a diet, uh, the man's diet, and we showed that men who were eating the Mediterranean diet had better sperm count than men who were eating the Western diet. So that's one thing that's pretty clear. We know that smoking, smoking is a huge risk factor for low sperm. So smoking, there's another one. That's not, you could say that is chemical, but I'm putting it under lifestyle. So, in some sense, everything is chemical.

• 27:18Speaker 01

  Um, then there's obesity and exercise. And the usual, you know, if you're obese, your sperm count is lower, your fertility is lower. If you don't exercise, same. Um, stress is really important and we, we asked, um, men who gave us sperm sample center studies, uh, about their stressors in their lives, in their daily lives, you know?

• 27:42Speaker 01

  Typical stressors are moving and change of job and change of partner and death of a loved one and divorce and, you know? And if you look at those, you see that the more stressors the man has, the lower his sperm count. That's not surprising, but there's another factor. So we're talking about a lot of lifestyle factors. Alcohol is important too, particularly binge drinking. You know, Saturday night, five drinks, six drinks, eight, bad, bad for your sperm. So, um, and we can find more, but the, but the point is here that it's not just these chemicals that are hormone disruptors that are, I'm caring about or that other people care about. They're also the lifestyle factors.

• 28:25Speaker 01

  Now in terms of fertility, there are sort of different factors and they're also important. And they particularly have to do with the female side, I think. Um, by the way, those factors also affect female fertility, obesity, smoking, all those things, stress, all that. But, um, the availability of contraception, which primarily has an impact on females, I think, um, drives down the fertility rate. So if you have contraception available, you're going to have fewer children. Okay. Um, if you have women educated, you're going to have fewer children. If you have women in the workforce, you're going to have fewer children. Right?

• 29:10Speaker 01

  So women's place in society is very important for the fertility rate. So that's a very different kind of factor, but it's not a chemical. Right? So if you put all those aside, I would say what you're left with is the chemical and we can talk about that. But I just wanted, I didn't want to give the impression that I'm all about chemicals.

• 29:31Chris Williamson?

  No, I mean, we've, we've covered, you're the first person that I've spoken to about endocrine disruptors and what's happening, I guess, um, physiologically inside of the body, uh, beyond diet, diet and sedentaryness and, and stuff like that. I'm going to guess that, uh, sleep, poor sleep, um, which we are increasingly, uh, subject to screens at night, distraction, blah, blah, blah. I'm going to guess that makes a difference. Can I give you my, uh, bro science theory, uh, about why testosterone levels are socially mediated by contraception? So, uh, as I'm sure that you're aware, men who are around guns see an increase in testosterone. If I was here and I just had weapons strewn around the table, my testosterone would be a bit higher.

• 30:16Chris Williamson?

  Probably if I was wielding a sword as well, it would be a little bit higher. But the same thing is also true for men who are around women that are fertile. So if you give men the T-shirts of women who are ovulating and you get them to smell it, they're able to pick those women. You can show men the silhouettes of women walking and the women who are ovulating, men are able, they prefer that. There is something in their gait design that changes based on the stage of their ovulatory cycle. So I think, it's neuroscience time, I think that the artificial suppression of women in men's local environment, their fertility through hormonal birth control, the coil, et cetera,

• 31:00Chris Williamson?

  et cetera, is causing men, because that's another huge mediator. If you were, if it was me and a bunch of grandmas or three-year-old girls, I'm surrounded by females, but I wouldn't be surrounded by fertile females, that would have an impact on my testosterone level and presumably on my sperm count. So it's my belief that you've got everything that you've spoken about, plus this evolutionarily mediated testosterone and sperm mechanism, which occurs by men just being around fertile women, and because there are fewer fertile women because of contraception, that's also causing a problem.

• 31:36Speaker 01

  And Chris, I want to use a word here, which I'm sure you know, but it's really relevant, and that's pheromones. Yes? So the pheromones that are produced, and that's, that's what the T-shirt you were saying, that you give a man a T-shirt from a fertile woman, those are pheromones. And the influence of those pheromones on men's hormones and sperm count, I don't know a study specifically where, you know, you looked at sperm count in relation to, but I suspect it's there. The other thing is, we do know that when the woman, you have a couple, the woman is pregnant, his testosterone goes down.

• 32:17Speaker 01

  Because he's not, he's gonna be staying at home and not playing around for a while.

• 32:21Chris Williamson?

  Oh, yes, of course. Men's testosterone goes down when they get into a relationship, when they get married, and then when they have children, we know less risky behavior. That wouldn't, so I, that mechanism works. Okay, so we understand that the mechanism of a, being around an unfertile female mediates it. What we don't know is how much is this happening en masse? How much, here's another one that I haven't even thought about until now. How much of the increasing social isolation of men, you know, just spending time in their house, maybe they work remote, maybe they've got a job that allows them to work from home, maybe they spend a lot of time on screens, as opposed to mixing, going to church, going to bars, going out dancing, playing sports, doing things that would have allowed them

• 33:03Chris Williamson?

  to interact with women, fertile women, in the environment. So, yeah, we just have, it's this huge cocktail of social, hormonal, psychological, physical, environmental, lifestyle impacts that are all coalescing to like neuter the human race, both men and women.

• 33:28Speaker 01

  Yeah, I don't want to go so far as to say neuter, but certainly alter the hormones of.

• 33:35Chris Williamson?

  You're the scientist, I'm the one that can use the explosive language.

• 33:39Speaker 01

  You can do that, you can do that. But, um, I, and I think all of that is extremely important. However, I don't want to lose sight of the ability of chemicals to also alter our body's hormones.

• 33:56Chris Williamson?

  Let's get into the, let's get into the chemicals. Tell us, tell us what we need to know.

• 34:02Speaker 01

  Okay, so can we go back to the unborn fetus? And I'll tell you the story. So, I'm flying to Japan with a colleague named John Brock, who's a chemist, wonderful chemist. And he works for CDC. And CDC Centers for Disease Control, they've just figured out how to measure a whole lot of chemicals in a lot of people for not a lot of money. So this actually changed the whole research field, because until then, we didn't know how to look. If I want to know your levels of things in your body, chemicals in your body.

• 34:44Speaker 01

  I can't, I can ask you, I can ask you how much you smoke, I can ask you how much drugs you took, blah, blah, blah, blah. I can't ask you how much bisphenol A is in your body, BPA.

• 34:54Speaker 01

  Right? I can't ask you. So, the only way I can know that is to look inside your body. And it turns out that a lot of these chemicals are water soluble, and so they're in the urine, and that makes it very easy. Okay, the ones that aren't water soluble are usually fat soluble, and they're in the serum, and so that's another way you can do it, but that's a little more difficult because you have to draw blood and stuff. But urine is really easy. So, when CDC could measure tons of chemicals in, in urine, it changed our research field entirely, forever. Okay, so here I am on the plane with John, and we're having a long flight to Japan, and he says, "Shanna, you should study phthalates." Okay?

• 35:40Speaker 01

  And I said, as you might, if you didn't know better, what's phthalates? Right? And, because I had never heard of them. And, um, by the way, my background is in mathematics, and, you know, I'm not a chemist, so, you know, this is like, phthalates, what are phthalates? Um, so, uh, he told me, and he told me something about where they're found, which I can tell you in a minute, but he also said they're in everybody. So that's fact one. Phthalates are measurable in everybody's urine in the United States, in the sample, representative sample they looked at. And then he told me the kicker, which is that at the National Toxicology Program, scientists had fed these same phthalates that we have in our bodies to rats.

• 36:26Speaker 01

  Pregnant rats, early in pregnancy, and what they found was, what I've already told you, that the male offspring are incompletely masculinized. They are born with genitals that haven't made the full transition from neutral to masculine. Okay? That is huge. I mean, really, this was the first time that, that anybody thought that this could happen on this physiological level, in utero, from these chemicals, okay? So I was like, wow. And then I thought...

• 37:02Speaker 01

  Naturally, being an epidemiologist, at that time, I asked, "What about humans?" Because he told me about rats. So I said, "Well, okay, so then if we want to ask that question of humans, what do we need?" So we have to know how much thalates, because in the lab for the rats, you gave the measure. You could know how much, because you gave it to them. But we can't give that to people. It's unethical. You're not allowed to feed test chemicals to subjects, except for very rare circumstances. And so we'd have to know how much they accidentally got in their bodies. And that's when we realized you could do that in urine, because John had measured it in urine, right?

• 37:45Speaker 01

  So, okay, so all I need to do is get the urine of pregnant women. And I got half the equation. And fortunately, I had a study in which I had saved the urine of pregnant women. It's always good to save urine, because it's cheap and it's easy to get. And I always tell my students, "Save the urine, save the urine if you can, because it's going to come out useful." And here it was, being extremely useful. So we got out these urine samples from the freezer, sent them to the Centers for Disease Control, and asked them to measure the thalates in the urine. And we found them, tons of them.

• 38:26Speaker 01

  Okay, so then to finish this, I had to do the second half, which was look at the offspring, right? So to do that, I had to contact the mother and say, "Could you bring your baby in so we can measure its genitals?" Kind of weird, right? But we did that, and women did bring them in. And what we found was that humans, like rats, had this condition, which is called the thalate syndrome. So, I mean, this was so important, because this is a, aside from one other syndrome, which is alcohol, fetal alcohol, I'm sure you've heard of that.

• 39:09Speaker 01

  There are no syndromes named after chemicals of this kind. No prenatal exposure produces this.

• 39:17Speaker 01

  Cluster of adverse outcomes in, you know, named after a chemical. So here's the phthalate syndrome. And it was just the same as in the rats. By the way, in the rats, the researchers had been measuring these things for about 50 years. They had been using AGD, intercellular distance, and these other measures as measures of what they call reproductive toxicity. That's part of their protocol, it's part of the NTP protocol. But no one had done it in humans. So what we had to do was say, well, what does that look like in humans? What is it? How do you translate that exam in a rat to that exam in a female?

• 40:02Speaker 01

  Or a, an offspring of a female human? So designing that protocol, that exam was, you know, different. Okay, it was difficult, but we did that. And then we had to show it was repeatable and reliable. And two people got the same measure. And, you know, if you did it a week later, you got the same result and all this kind of thing you have to do that. So we did that and published and it was a, it was a groundbreaker. It was huge. Um, and it led to legislation to keep phthalates, you know, out of certain things, not quite the right things. They took them out of children's toys, which is not related to mother's exposure.

• 40:46Speaker 01

  But anyway, they were on the right track. Limit phthalate exposure. And, um, and then other people started seeing that there were other chemicals that could do this. So it's not just phthalates that lower testosterone. There are other, and the class of chemicals that lower testosterone are called antiandrogens. Okay?

• 41:09Speaker 01

  And then, at the same time, a researcher

• 41:15Speaker 01

  in Washington State discovered that there was an estrogen

• 41:23Speaker 01

  influencing chemical.

• 41:27Speaker 01

  And that was bisphenol A. So, you know, bisphenol A makes plastic water bottles hard. And so gradually, people started saying, oh, and what else can go wrong? And what can influence thyroid? And what can influence this hormone and this hormone? And that class of chemicals are called endocrine disrupting chemicals. Because as a class, they disrupt the endocrine system. So there's eighty hormones in the body, so a lot of room. A lot of room to defer disruption. And there's like, maybe a hundred thousand chemicals out there in commerce. So there's a lot of room for chemicals to affect that. And so this is a huge job, saying, how can this huge class of chemicals in commerce

• 42:12Speaker 01

  affect these very large number of hormones, which govern our entire function? Our entire function and health is governed hormonally. So it's extremely important. And it plays a big role in the sperm story and in the fertility story and, and what we're talking about today. So that's my rant on chemicals.

• 42:34Chris Williamson?

  And what you're talking about here specifically is, or at least so far, natively, what does presumably a mother's consumption do to impact the development of a baby in utero? But then that baby is going to grow up and start consuming things that are encased in BPA water bottles and that have got phthalates that may be in drinking water and whatever, whatever. When it comes to the culprits of environmental and lifestyle absorption, consumption, what are the, what are the big movers? What is it that people are exposed to, objects and things

• 43:19Chris Williamson?

  that are causing these to go into our bodies? Whether you're a mother or a five-year-old child?

• 43:26Speaker 01

  Food, I would say, is the primary, is number one. Because there's so many opportunities, and we can talk about what those are. There are also

• 43:38Speaker 01

  the chemicals we put on our body, like

• 43:43Speaker 01

  skincare products, makeup, because they're absorbed. So when you, when you use a chemical, it will influence you to the extent that it enters you. If it doesn't enter you, you don't worry about it, right?

• 43:57Chris Williamson?

  It's still, it's, it's over the other side of the room still.

• 44:00Speaker 01

  Right, right. They're not gonna hurt you. But unless it's in your air duct or something. So the, the three ways you get the stuff in your body is you eat it or drink it. That's ingestion. You breathe it, respiration, or it's dermally exposed through your skin. And it turns out that several of these chemicals are designed to increase absorption. They're put into products. Phthalates particularly are put into products, so they'll go into your skin.

• 44:27Chris Williamson?

  Wow, so the thing, the, the thing we don't want in us makes stuff that we do want in us more likely to carry the thing we don't want in us into us.

• 44:36Speaker 01

  Exactly, into us.

• 44:38Chris Williamson?

  Fantastic. All right, um, when it comes to, when it comes to foods, what do you mean when you say foods? Is it the content of foods? Is it the packaging of foods? How so? How can we avoid it?

• 44:47Speaker 01

  All, all of the above. So, um, the, um, go back to the, the growth of the, of the, of the food. So there's the question of organic and inorganic, which is another thing we can talk about. But I just want to add that some chemicals are added, like phthalates, to increase the absorption of the pesticide into the plant. So even, you know, you, the pesticide will be harmful on its own, and it will also be harmful because phthalates are entering that lettuce or that asparagus and, and because they're put in deliberately to increase absorption. So, so in the growth process, you have the concern about endocrine disruption. And then in the

• 45:34Speaker 01

  Packaging from the farm to the factory, to the grocery store, to your house. All along the way, you have the option of introducing these chemicals. Milk is a great example. So, and I went, I was at a farmer's market. I talked to the farmer and he's very proud of his milk. He said, I'm, this is organic, uh, you know, food for the cows is organic and so on and so forth. And I said, great, and how do you milk them?

• 46:07Speaker 01

  You see it, right? I can see you're smiling, you, you got it. So, m- milk that's hand milked has no phthalates and other chemicals in it. If the far- if the farm was organic. Milk that's collected through a milking machine, which has lots in tubes. You've seen those pictures, the milking machines, all the tubes. Those are conveying the phthalate that's in the tubing, which is put there to make that tubing soft. And it turns out that the chemical is not bound to the matrix that it's in. It's very easy to come out of the matrix and enter, particularly if the, if it's a warm product.

• 46:46Speaker 01

  So the milk is warm, the phthalate goes into the milk, it goes into the bucket, it goes into the bottle, it goes into us. And you can think of this for lots and lots of food, making spaghetti sauce and making any product that's going to be processed is going to go through some contact with some plastic. There's, it's unavoidable. So it, it's, it's in the growing, it's in the shipping, because the shipping containers contain plastic. It's in the processing. And then there's concern of how we store it in our fridge and how we heat it. And I'm sure you've heard, you never should microwave in plastic, right? I mean, no, no, no, that's like the biggest no.

• 47:31Speaker 01

  And, and, um,

• 47:34Speaker 01

  Yeah, so I actually want to do a little study called Farm to Fork, where you take this little tomato or this, you know, bottle of milk at the farm and just track it and see what the levels are of these chemicals all along the way. But no one's given me the money to do that.

• 47:54Chris Williamson?

  Maybe, maybe someone will after this. Presumably as well, um, the increasing shelf life that we have of produce uh gives them more time to be wrapped in uh plastic to sit on a shelf to accumulate in that whatever preservative or maybe something's been pasteurized and because it's been pasteurized, it's able to sit without accumulating bacteria and going off. All of this is just more opportunity for these endocrine disrupting chemicals to just leak into the food and then for us to absorb them into our body. Um, just to kind of round out that from a lifestyle perspective, what are the principles that you try to follow yourself or what are the biggest movers people can do to try and

• 48:38Chris Williamson?

  avoid uh this stuff presumably eating organic, trying to get there? I mean, is there someone that wraps their tomatoes in a paper bag? Like what, what, what are the, what are the things people can do beyond do not microwave your food in plastic? This podcast should be called do not microwave your food in plastic. Beyond that, what are the other lifestyle changes and things people can do either when shopping, storing, et cetera, to, to maximize this?

• 49:02Speaker 01

  Yeah, so I've, I've had some experience going around the supermarket with people who are concerned and, and actually we filmed that and that's another story. But, but um, it's, it's really interesting to, to do that and pay close attention to, you know, how things, how much plastic there is in our supermarket and how unavoidable it is. It's not completely unavoidable. If you go to the vegetable area, the produce area, you can see in some supermarkets packaged lettuces and in some, you know, some places just open.

• 49:45Speaker 01

  Heads of lettuce and it's so refreshing to see that and and um I did a little experiment with some friends I was going around with and I said, okay, let's weigh these. And it turned out that the unpackaged ones actually were a lot cheaper than the packaged ones. That's a little aside, but but they're also, um, you know, and that's true of of fish that's already been filleted or meat that's already been, you know, cut up or whatever. There it's always going to be more exposure and more cost. So it's really to people's advantage not to, you know, to get as simply as possible. And my ideal is if you have a farmer's market near you, which not everyone has the good fortune to have,

• 50:25Speaker 01

  you go to that farmer's market and you buy it in the simplest, most primitive form possible, out of the ground if possible. Take it home, wash it, and then don't put it in plastic. There are other kinds of bags you can buy. You can buy beeswax bags. You can buy I that this area is kind of under served, I would say, by industry, but I think it's growing. That's getting more more options. There are bags that are safer. Yeah.

• 50:55Chris Williamson?

  From my perspective, one of the biggest changes I made less long ago than I would like to have known, but as soon as I kind of found out, um, there's a number Pyrex do quite a few of glass, uh, Tupperware containers. Now, I'm yet to I'm yet to find one that has a glass lid. Uh, most of them tend to have a plastic lid, plastic seals, but I'm going to guess, yeah, I'm going to guess that the food is that the food is actually touching the glass part, which is the bottom, the main bottom bit. You can go on Amazon and get these. Uh, typically, I think you want to get a two liter or above. One liter sounds like a ton of food, but when you actually look at the size of a piece of Tupperware, that's only a liter. It's not actually that big. So go two liters or above and, you know,

• 51:40Chris Williamson?

  just replace you right now. Get rid of the Tupperware, get rid of whatever you you're doing and Pyrex or some other company will make some really great glass bowl. I'm going to guess you're okay with glass. Glass is all right?

• 51:50Speaker 01

  Absolutely. The best. I love that. Yeah.

• 51:54Chris Williamson?

  Are there any types of plastic that are worse or better for us? So let's say that somebody can't avoid either due to they don't have a farmer's market near them, they are battling against budget restrictions or whatever it might be. Is there something that we can look for when we're looking at the plastics of the foods and the drinks and stuff? Is there better and worse? And how do we work that out?

• 52:18Speaker 01

  So silicone products resemble plastic and they are safer. They are not, I understand for my packaging friends, they are not ideal, but they're certainly better than, they are not going to contain phthalates, they're not going to contain bisphenols. We didn't talk much about bisphenols, but the bisphenols, BPA, BPF, BPS, BPFS, there's now more and more of them, because, by the way, when people said, oh, I don't want BPA, then the manufacturer said, okay, we're taking it out, but we're not going to tell you that we've put in BPF and BPS, which do the same thing, by the way. So that's, that's, that's, that's been going on for quite

• 53:02Speaker 01

  a while. This thing we call whack a mole, which is, you know, just swapping out, you know, things people don't want with things that are just as bad, but

• 53:12Chris Williamson?

  They don't know about.

• 53:13Speaker 01

  Yeah, they don't yet know about them. So anyway, yeah, if you can, silicone is preferable. Glass, like I said, is perfect. So China, you know, any, anything that's, you know, pottery, not lead, pottery without lead. And I buy a lot of things in glass and then I wash out the jars and I just save them. And I have a couple of jars full of glass jars and I just use those to the extent.

• 53:45Chris Williamson?

  I've heard you talking, I've heard you talking before about the number in the triangle on the recycling thing. What is that?

• 53:56Speaker 01

  I think that's a moving target, Chris. I don't actually ascribe to that anymore myself. I don't. I believe that recycling is not going to solve the problem for us. And the purpose of those numbers is to get you to recycle, to buy recyclable and, you know, to increase recycling. But the problem is that if you have a chemical that's harmful to start with, and when you recycle it, it's still harmful. So I'm not, I'm not, you know, I'm, I've moved my emphasis from recycling to trying

• 54:41Speaker 01

  to get these things out at the beginning, you know, so that we don't have to keep exposing ourselves. Yeah.

• 54:47Chris Williamson?

  All right. So 10, I'm just thinking about some of the other places that people might consume stuff from. Presumably, plastic bottles of water, not good. Much better to get bottled water, bottled water from glass. What about those, you know, the very large cooler, like water cooler in the office type things? Is that the same?

• 55:09Speaker 01

  Many of them are plastic.

• 55:11Chris Williamson?

  Right, yeah. But any plastic. So there's basically, if it's plastic, assume that it's bad?

• 55:17Speaker 01

  Right. That would be my assumption. It's still proven otherwise. Yeah.

• 55:20Chris Williamson?

  Okay.

• 55:22Speaker 01

  And by the way, can I just say that there are ways to treat water?

• 55:29Speaker 01

  It's not just the container now we're worrying about. It's also the water itself. So I'm sure, have you heard of these micro nanoplastics?

• 55:39Chris Williamson?

  Presume that I haven't.

• 55:40Speaker 01

  Okay. So this is a kind of a new development in the field, and people are realizing that the breakdown products of recycled products and

• 55:53Speaker 01

  Uh disposed of, plastic products are not actually leaving us, they're re-entering in various forms. So they're re-entering, for example, in our water and in our air, and they've now been found alarmingly in many cells in the body. And the scarier thing about these is they're very, very tiny, and they have two possible adverse effects, and this is just under, in a research stage now. So, grain of salt, but they're, um, they're have a physical presence that can be harmful, like asbestos. Asbestos is harmful because primarily

• 56:34Speaker 01

  it's physical presence. And they have a chemical presence, and they can carry with them not only the chemicals from which they were produced, but other chemicals they pick up along the way. So, you know, keep your eyes out for research on, and maybe sometime I'll, I'll know more and I'll come back and talk to you about it. But it's, I would say this is the, for the last couple of years, this is the most important new development in this field, that these chemicals that are put out there, you know, in the plastics that we think we've gotten rid of, they're here, they're back, you know, it's like, I mean, on that, you know, it's, yeah.

• 57:14Chris Williamson?

  So my, you can tell me whether or not my solution actually works for this. For years, for over a decade, I would only drink water from a Brita filter, you know, like a classic desktop style filter. I then kind of got red-pilled about that doesn't, it may get rid of something, but it's not getting rid of really any of the things you want it to get rid of. I'm now using a four-stage reverse osmosis filtration system. In your experience, if it's of high quality, how good is that at getting rid of what we need to?

• 57:44Speaker 01

  Yeah, I would say I would look at what it's made of, what it's, the components are made of, and where is there plastic in that device?

• 57:54Speaker 01

  Because obviously you'd prefer not to pass the water through plastic. I want to mention an alternative, which is what I happen to use, which is a desktop or tabletop distiller. So we actually distill our water. It's very simple. It's free. You don't have to change any filters. You don't have to, you know, you just put the water, it boils it, it steam, steam comes up, and then it condenses and it comes down into a glass container. And that's it. So there are alternatives. RO is good. Distillation is good. Filtration is complicated, in part because of the filters, what's in the filters, and you have to change them and you have to pay for them.

• 58:36Chris Williamson?

  Yep.

• 58:37Speaker 01

  Yeah, yeah.

• 58:39Chris Williamson?

  Yeah, there's two, the, the brand that I use is Aqua True. They're great. I do need to look at what pipes are internal to the system. But I certainly know that the, the carafe that it fills at the front is glass.

• 58:53Chris Williamson?

  And my solution is I have, this is a steel,

• 58:58Chris Williamson?

  steel shaker, and I just fill like five of those and they live in the fridge of the door. So I always have water going from full stage. The other big one that I think sometimes is sold out, sometimes isn't called a Berkey. So this is a charcoal filter, like a multi-level charcoal filter thing. And the whole thing is made of steel. So in terms of, in terms of plastic, I think it's made of steel. I really hope that the spout at the front isn't a plastic spout. But I can't remember, and I don't own one, but I'll, I'll, I'll ask my friends about that. But a bunch of my friends have got those. So those are the two that I know, at least from my experience and what my friends are talking about, Berkey and Aqua True. Those are the two for water.

• 59:40Chris Williamson?

  And thinking about, you know, everyone's thinking about how can I get more hydration? I know that water is really important for me and I need to stay hydrated. But, you know, there is a world in which you increase your hydration at the cost of increasing the amount of phthalates and microplastics and BPA and stuff that you're.

• 59:59Chris Williamson?

  That you're being exposed to. One of my friends lives in Dubai and I went into his fridge and he's a health conscious dude and it was just bottles and bottles and bottles of Evian. You think it's high quality water held in plastic bottles. So I'm like,

• 1:00:12Speaker 01

  Right.

• 1:00:12Chris Williamson?

  Dude, I want, I really wanna, I was gonna buy him one of those things, but I don't think that they shipped that. So, um, okay. One thing, one of the most interesting things that I learned from you is these chemicals impact behavior. So the way that children play, the, the, the way that they, boys and girls learn to speak and stuff like that. Can you explain what the effects are there?

• 1:00:34Speaker 01

  Sure. Um, so just as the genitals need hormones to develop and to differentiate between males and females, they're different. That's just also true of the brain. And, um, this is kind of a controversial topic in some political circles that people don't like to say that the brain is sexually dimorphic, but it's, there's no question you can see.

• 1:00:59Chris Williamson?

  This is a, this is a safe space for you here, Shanna.

• 1:01:02Speaker 01

  Yeah, right.

• 1:01:06Speaker 01

  And, um, so the changes, uh, in the brain are influenced by testosterone, just as the genitals are. And not quite the same time. It's later in, it's also in pregnancy, but it's later in pregnancy. Okay. So, um, there's a lot of things you can see on MRIs, but I, you know, can see those differences between males and females in different parts of the brain. Um, I think you're referring, by the way, I, you've read my book, right? Countdown? Is that how you know? Yes. So I want to put in a plug for Countdown, maybe you can.

• 1:01:45Chris Williamson?

  Of course.

• 1:01:46Speaker 01

  Yes. Um, in Countdown, this is one of the things we discussed, but it's not the main focus because the book is largely focused on reproduction function. But I have a colleague, had a colleague, um, who said, Shanna, the brain is the biggest sex organ in the body.

• 1:02:07Speaker 01

  It's true that the brain is influenced by sex hormones, just as the genitals are. So if you're going to mess with the estrogen and testosterone, you're going to mess with the brain. And specific things that we looked at was language development. And so, yeah, so how do males and females differ? Well, one way they differ is that, and this is going to sound very, you know, there'll be people that won't like this again politically, but females have better, earlier language development. And they know, if you have a child, you know, you see, you know, how quickly they acquire

• 1:02:47Speaker 01

  words and, and, and, and, um, and men, on the other hand, have a better spatial ability. That's the joke about the, you know, a woman will never ask, will never find her way out of a, you know, a box. I'm like that. I always lose my way, but, um, men are much better spatially. So, um, so we, we found in our study, we asked four-year-olds, um, the mothers of four-year-olds, how many words the child knew or could understand. We did it in our study and also with a colleague in Sweden. And we found that the phthalate levels were related to the number of words the child knew or understood at age four.

• 1:03:32Speaker 01

  That particularly in females. There wasn't much in males, but in females, it was pretty marked. Um, the other study that you're referring to, I think, is the play behavior. And this is even more controversial because it's based on the assumption that the behavior of children in play and in their daily activities is sexually dimorphic. And that, um, you can ask a mother, how often does your child play with guns or play with cars or play with tea sets or play dress up or play with dolls?

• 1:04:11Speaker 01

  Well, first of all, they did this with monkeys and they showed that the monkeys made the same choices as human children. That a male monkey will go for the car and woo with the car and the female monkey won't.

• 1:04:29Speaker 01

  And it turns out in our study, when we asked the mother about the play behavior of the child and ranked their answers as male and female,

• 1:04:43Speaker 01

  the male typical behavior was less male typical in men, boys who were exposed to phthalates. So that's for what that is, it's, it's a suggestion, I would say, that exposure to these chemicals in pregnancy, during pregnancy, because it all happens in pregnancy, are going to affect the masculinization of the brain.

• 1:05:12Chris Williamson?

  Could this change gender identity?

• 1:05:15Speaker 01

  I knew you were gonna ask that.

• 1:05:21Speaker 01

  That's a $64,000 question, isn't it? Yeah.

• 1:05:26Speaker 01

  So there's some indication that it could, but I wouldn't say we know at all the answer to that question. But here's two things.

• 1:05:40Speaker 01

  If you look at, so I have to tell you about twins.

• 1:05:44Speaker 01

  Okay. So if you have, I'll start with rats. They're not twins. There's like 10 of them in the uterus or something. So the, the rat, guess if it's a male rat between two females, he's slightly less masculinized at birth. And that's true of his H E D too, by the way. And the female between two males is somewhat masculinized.

• 1:06:10Speaker 01

  Okay.

• 1:06:10Chris Williamson?

  So it's like a uterus environment that, that where they're bleeding between each other. Right? Okay.

• 1:06:17Speaker 01

  Exactly. And that's called the, the in utero position effect. And it's been known for a long time. What about humans?

• 1:06:30Speaker 01

  Well, it turns out that when, if you, this study looked at twins in Finland and found that female, female twins were more likely to get married and had more children than male, female twins.

• 1:06:49Speaker 01

  So they were maybe a little less feminized if they had a male co-twin. Okay, now I'm going to turn to your question. It turns out that if you look at twins, and this is a very nice and pretty recent study. You look at twins, the twins that have a partner, this co-twin of the opposite sex are more likely to be gender dysphoric.

• 1:07:20Speaker 01

  So they're getting an influence, they're getting some influence from their co-twin. So.

• 1:07:26Chris Williamson?

  How, has this been done with adoptive twins in like a Pelominesque style? How do you know that this isn't just sisters growing up with brothers, brothers imprinting behaviorally, social roles theory type stuff, social learning theory?

• 1:07:40Speaker 01

  I, not from that study, but the, um, the brains, you can look in MRI at the brains of the male and female and you see, um, that reflect there. I don't have that.

• 1:07:57Chris Williamson?

  So less female typical.

• 1:07:59Speaker 01

  Right.

• 1:07:59Chris Williamson?

  Brain development in the female that has the, right, yeah, understood. And there's a really great, I brought this up a couple of weeks ago on a podcast. There's a really great bit of data around MRI scans of 10-year-old boys and girls. And the computer can predict with 90% accuracy, whether it's a male or a female, just based on the brain scan. But that's almost the same level of accuracy that humans have when looking at the face of another human. So if you cut my face out and showed it to someone, it's around about 90, it's a tiny little bit higher. So your ability to, I know what a man or a woman is, well, so does the MRI machine and it's around about as accurate as you are.

• 1:08:42Chris Williamson?

  But even in utero, you know, I've been over this, David Putz, who did a phenomenal bunch of work on this, David Geary as well, who did a ton of great stuff on this. In utero, brain scans of developing fetuses, they show sex differences, I think, three months old, three months, four months, five months old. You can start to see, that's, you know, you're a minus six-month-year-old. There, this isn't anything to do with socialization.

• 1:09:11Speaker 01

  No, no.

• 1:09:13Speaker 01

  That, that's because, Chris, the, the.

• 1:09:18Speaker 01

  Time in your life that your cells are most rapidly dividing and forming organs is then. It's all happening then, you know, in utero. But I mean, it it changes, you know, like generals are very early and brain is later. But it's that's that's a sensitive period. You asked me before about sensitive periods and I want to just mention some other. Um, so there's the in utero period, of course, we've talked about that a lot. There is a period right after birth called the mini puberty. And it's the first six months of life. And there's been some work showing that that period is very sensitive to environmental insults as well.

• 1:10:02Speaker 01

  And then there's puberty, which is another period. You want to look for the periods of rapid cell division. That's that's.

• 1:10:10Chris Williamson?

  Yeah, yeah.

• 1:10:11Speaker 01

  So so puberty. Um, and then for women in pregnancy themselves when they're pregnant. And then for menopause, there's a lot of changes in menopause. So very little study, very little studied in menopause, but but.

• 1:10:28Chris Williamson?

  That's that's fascinating.

• 1:10:30Speaker 01

  Yeah.

• 1:10:33Chris Williamson?

  We're talking about menopause. What is happening to the relationship between female and male age? And reproductive success or fertility in the modern world?

• 1:10:49Speaker 01

  I.

• 1:10:53Speaker 01

  It's very hard to say because so much of it is choice now. Um, right? Um, so, uh. Women, couples are postponing having children and so they're. The the natural default is, um.

• 1:11:11Speaker 01

  That women and men's reproductive function decreases with time, but women's much more dramatically, of course, at menopause, and men just decline very, very, very slowly until their death. So if you push women particularly into the period of lower fertility, natural fertility, you're going to have fertility, you know, either through because they're going to school or because they're in the workforce or because they want to do something else for a while. You know, that's going to... So I don't know how to separate that from the biological changes.

• 1:11:50Chris Williamson?

  Yeah.

• 1:11:51Speaker 01

  And I can't say... Yeah, yeah.

• 1:11:53Chris Williamson?

  I understand. I guess maybe one of the things that you could look at would be at what age do people start using fertility treatments more sooner? You know, there should be a volume, there should just be a number of people. And if there are more 30-year-olds or there are more 35-year-olds going in to use IVF or whatever, that would be an interesting place to start. But again, you know,

• 1:12:22Speaker 01

  I agree.

• 1:12:23Chris Williamson?

  It's kind of circumstantial.

• 1:12:28Speaker 01

  But I promised you something and I want to come back to it because we talked about fertility decline worldwide and I told you every country was declining. And now I want to tell you the exception. And that's Israel. And the reason is fertility includes artificial, you know, assisted reproduction births. It's just births. It doesn't say how they got there. And in Israel, people are guaranteed to children by, if they need it, by artificial, you know, ART, artificial reproductive technology. And, and... Their fertility has not declined. So, you know, that's pretty dramatic.

• 1:13:14Chris Williamson?

  Yeah.

• 1:13:14Speaker 01

  Every other country. And the other thing is that the use of assisted reproductive technologies has been increasing. I can't give you numbers on that right now, but it definitely has been.

• 1:13:28Chris Williamson?

  I have a friend who is, within the next two years, the company is already up and running, although it's dark at the moment. I have a friend who is doing embryo selection for a variety of traits. So you can go in with your harvest of 10 fertilized eggs, and they can give you a polygenic risk score for externalizing behavior, for autism, for IQ, for a number of other things. Obviously, it's not a perfect science, but it's pretty predictive, according to him. And that's already happening. I mean, that just straight up is happening now. I'm sure that you've learned about IVG as well, which is sort of the next stage beyond IVF,

• 1:14:12Chris Williamson?

  where you don't necessarily, you're not as restricted by harvest, you're not as restricted by a lot of different things. How... Well, actually, even before that, let's forget the new fertility technologies coming down the pike. What do you think the future of fertility has in store for humanity, kind of generally at the moment? What's your prediction?

• 1:14:38Speaker 01

  I would say the most, well, first, my first prediction is that we're going to rely on it more and more. Whatever form it is, we're going to rely on artificial reproduction more and more because of the decline in sperm count and fertility. I don't think there's any way around it.

• 1:14:53Speaker 01

  But the technologies are rapidly, as you say, rapidly increasing. And the one that's so intriguing to me and wondering what's going to happen with this politically and otherwise is the production of egg and sperm from stem cells. Have you heard about this?

• 1:15:09Chris Williamson?

  That's IVG.

• 1:15:11Speaker 01

  Yeah, okay, right, okay.

• 1:15:13Chris Williamson?

  Yes.

• 1:15:13Speaker 01

  I hadn't called it.

• 1:15:15Chris Williamson?

  Sorry, yeah, that's IVF. IVF and IVG is the pluripotent stem cells. Yeah, I mean, this is... Some dystopian, if you wanted to, some dystopian future where you have basically a million test tube babies, artificial wombs, and you just go to town. I'm pretty sure you do it, you can even do it from skin cells and stuff like that.

• 1:15:37Speaker 01

  You can. Yeah. Yeah.

• 1:15:39Chris Williamson?

  Yeah. When you think that a woman, a woman produces one egg per 28 days, how many trillion skin cells are there on my upper arm?

• 1:15:49Speaker 01

  Yeah. Yeah. So there's obviously a lot of scary scenarios here and a lot of hopeful scenarios. And politically, particularly now with the ruling of the Alabama Supreme Court, we have, you know what I'm talking about, right?

• 1:16:07Chris Williamson?

  Yes.

• 1:16:07Speaker 01

  It's, it's, it's going to be even more complicated. And I don't know where this is going. I mean, but this is, this is definitely what's happening right now. And, and part of the reason is that it's getting increasingly difficult to people, for people to make kids the old fashioned way. That's driving this desire for new technologies, right?

• 1:16:33Chris Williamson?

  Well, don't, don't forget, there's a decreasing desire for people to do the action that causes children to come about the old fashioned way as well. You know, we can go even further upstream than the difficulty of the mechanism, we just, the desire is, is also being muted. Yeah, it's, um, it's fascinating. It's, it's what a time to be alive, you know, to be studying this stuff. It's just endlessly, to me, this whole, it is apocalyptic, right? And I'm not, I'm not saying that I'm glad that it's happening. But in some ways, it's so, it's just endlessly interesting to me. What, what's going on socially, environmentally, psychologically, physically, hormonally, everything? How, how can we, you know, combat

• 1:17:15Chris Williamson?

  this challenge? It's a, a, a big problem. And if we don't fix it, it's not good. And, you know, for the people that say, well, there's too many people on the planet and all the rest of it, your wish is already going to happen. You're going to see population decline within, maybe even within our lifetimes, back end of the sort of 2000s, you're definitely going to see it start to dip. And then that, it could be precipitous. But here's the other thing, and this is like my, my super hardcore red pill, which is, For the anti-natalist subcultures that really don't want humans to destroy the planet and, you know, there's too many people on here in any case, and so on and so forth.

• 1:17:57Chris Williamson?

  A lot of people's ideologies, especially their political affiliation, is heavily genetically predisposed. It's not predetermined, but it is predisposed. If you are someone that wants to make a change in the world, the change that you're talking about will be washed aside by other groups that have lots of children, because those children are likely to have lots of children. So in 100 years' time, maybe it's Mormons, and it's the Israelites, and it's like whoever else is having a blue zone people. And you go, well, that's the culture. That's the culture that the future will inherit, because those are the only

• 1:18:38Chris Williamson?

  ones that have got positive birth rates. And yeah, another friend, here's the next level of the spicy red pill, which is, a friend said to me, she thinks that this fertility bottleneck is good, because it's basically culling stupid anti-human, anti-natalist cultures through this genetic predisposition to ideology, and that coming out on the other side, basically, it's the same argument, I think Thomas Sowell made it, about how

• 1:19:10Chris Williamson?

  the clergy is good, because it screens fanaticism out of the gene pool, that people that are, you know, super crazy. And I was like, wow, I mean, that wasn't me, that was just a friend that will remain nameless, but.

• 1:19:23Speaker 01

  Look, Chris, you have children?

• 1:19:26Chris Williamson?

  No, not yet, but I can't wait to become a dad.

• 1:19:30Speaker 01

  So if there's other couples that can't wait to become parents, and their opportunity for achieving that is taken away, I believe that they have been deprived of a basic human right. I think that is a right of people to have a child if and when they want it. Not, I'm not saying anything about they should want it, but if they want it, when, you know, they should be able to. And to the extent that products.

• 1:20:08Speaker 01

  That plastics and products and, you know, pan lighters and food containers are taking away this option is is terrible to me. It's it's it's uh it's unfair. It's unfair. And and I and I should add, by the way, that that if you have money and education, you have a much better chance of avoiding losing that option, right? Because if you're poor, you're working two jobs and you don't live near a farmer's market or a grocery store that has fresh vegetables and, you know, and you don't know to go on the web and look for alternative, you know, alternative, safer alternatives,

• 1:20:53Speaker 01

  you you can't do that. You can't take care of yourself that way. You're going to be more likely not to have a be able to have a child. And so it's it's not an equal opportunity for everybody to be deprived of having a child, right?

• 1:21:09Chris Williamson?

  Hmm.

• 1:21:10Speaker 01

  So there's this whole social issue here, too. Yeah.

• 1:21:14Chris Williamson?

  Yeah, there absolutely is. It's a, like I say, just what a time to be alive and to be thinking about these problems and sort of grappling socially with what's going on. That's I'm one of the things I'm really going to leave this conversation with is just how much of this is downstream from reduced libido. It sounds like such a basic bitch solution and to to all of the questions that we're asking. But if people just want to have less sex, all of the things that occur after that, the desire for relationships, the desire to get out of the house, the desire to leave the house, to leave the screen behind because I'm just I just got to find someone. Uh, yeah, it's it's amazing. Look, uh, your

• 1:21:56Chris Williamson?

  work is is really fascinating and it's the synthesis of a lot of different pet interests that I've got. Where should people go? They want to find out more the book, the why should they go to check out more of the stuff that you do?

• 1:22:08Speaker 01

  So you can go to shaunaswan.com and you can see, you know, lots of things I've said. And then you can go to Amazon or some other dealer, book dealer and order Countdown. Um, by the way, it's important that you put in two words, count down because countdown one word is something else, another book. So countdown. Um, yeah, that's, that's what I recommend. And, um, if this stuff bothers you, this bombardment of our lives by these chemicals, um, I suggest you go to Environmental Health Sciences and see what you can do about

• 1:22:53Speaker 01

  it. That's a group I work with and I think they're doing wonderful work to help turn this around.

• 1:23:01Chris Williamson?

  Hell yeah. Dr. Shanna Swan, ladies and gentlemen. Shanna, I really appreciate you.

• 1:23:05Speaker 01

  Thank you, Chris. I had a lot of fun.

• 1:23:07Speaker 02

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