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

what's happening to testosterone levels in men so that's a great question and actually I work with a research group and have been for quite a long time now since um you know 10 years uh looking at Trends and and the trend we're looking at right now is testosterone and it's difficult uh 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 um 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 uh showing that the use of testosterone particularly by young men has been climbing um alarmingly actually um so 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 yeah obviously one of the challenges we have here is are young men taking testosterone because they are suffering with the effects of low tea erectile dysfunction low energy low mood etc etc or is it because of increases in body dysmorphia or unrealistic representations of of men in meteor and they feel like they need to use testosterone as performance enhancer to become more masculine or to become more muscular and stuff uh 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 AA ailable uh I know more guys that know their testosterone count than know their sperm count that's a good good point that's today and probably in the US um but um sperm count has been under study for uh 65 years so there 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 previs ectomy 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 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 interesting yeah it's so interesting to me you know I again uh maybe again you you're probably right this is my not only weird bias but also my Austin podcast bro bio haacker World bias coming into play where all of my friends know that they're at 755 Nan nanog per deciliter and and they're going to try and get up to 900 because blah blah blah uh and I don't know who knows their sperm count um just before we get onto sperm count tell me from the testosterone it seems there are some uh sort of I guess uh rough hee signals that indicate the testosterone is going down um how important is testosterone you know there is a uh somewhat in the medeor of a demonization in some ways of of testosterone in men or 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 your world 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 let me back off okay 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 in rodents in rodents it's stay 18 to 21 but in humans not so much we know that it's in early first trimester uh at that time genetically programmed if it's a genetic male uh programming will um start the production of testosterone by the testes formation of the testes then testosterone gets produced 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 anog general distance which we should talk about for sure so glad that that's I'm so glad that's your favorite I was waiting for you to bring it up 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 aner gental 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 lengthwise 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 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 so and other things happen the testes don't descend into the scrotum and the penis is actually smaller which a lot of people get upset about and other things so so that you know fulfilling that potential of a male typical General requires you said is it important I would say most men would say that's pretty important yes okay roll me forward because what we're talking about there presumably is um endocrine disruption in the mother which impacts the growing fetus natally what about when uh mother and son are no longer attached what how important is testosterone for development as we move into adult yeah so the testosterone is important at many stages it's important for um puberty it's important for other markers of male development um and one of the things that's really key is it's important for libido um so um and by the way it's not just the male I just want to put in a little word for the female here so will 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 plastic soft that's the phalates now when the mother or just a woman doesn't have to be a mother is um exposed to less well actually more phades then she is less satisfied sexually so we found that out by asking women we said um 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 thides and it turned out that when the woman had low thides she was less satisfied and she had sex less often what does low phalates relate to from a testosterone in female perspective in both males and females phalates lower testosterone okay H but you said low phalates mean low testosterone would it not be high phalates would it mean low testosterone I meant to say low phalates yeah low low testosterone right phalates come in testosterone goes down understood high phalates low testosterone in both men and women okay presumably this is a double-edged sword if women who are high in phalates lower in testosterone sexual sex less sexual satisfaction and also The Men Who in testosterone have lower libido probably lower um like erection quality and and stuff like that so you have a an environment an endocrine environment here which is reducing sexual satisfaction for both partners and their ability to satisfy each other as well correct and and I do not have evidence 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 uh it's it's really serious now no one has linked that specifically to an endocrine disrupting chem but I cannot believe given what we know about the action of these chemicals that it is not playing a role yeah go ahead I was just say that 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 right and the other one is the 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 uh very strange yes 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 are 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 Steven 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 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 uh 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 and they're all you know social psychology SL evolutionary explanations that come into attraction but if we just straight up say libido's lower like if we just have that just as 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 just less bothered about being 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 it's a very cerebral cognitive kind of um like right brain approach to people are reasoning themselves into having kids or reasoning 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 uh men and women uh 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 un when I was at University uh 15 years ago that started at University oh God 18 years ago now and when I went there it was still this sort of very driven Larry L 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 know 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 um 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 D 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 of person that wants to have sex once a week your desire your um motivation to go out and get a partner is going to be really different yeah yeah I wanted to mention you you mentioned briefly uh the effective 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 and Stanford um I think there's probably half a dozen papers on this and it's really a lot and I mean first of all men and women 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 add up to is you die earlier so here's something that you exposed to Prat 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 exposures during pregnancy are most important for your whole life Health everything's developing then right what is the relationship between testosterone and sperm count for men ah well if you don't it's complicated men who who use testosterone supplementation do not produce sperm I do you know that of course yeah you do well I mean I 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 the opposite the opposite however um for the maintenance of the system you need adequate testosterone so on an ongoing basis um for the system to work properly and it's not just directly testosterone sperm it's you you need adequate testosterone so interfering with that um is going to mess up your brain mess up you know the production of sperm mess up whatever the whole the whole gamut 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 uh sperm count but what about too little 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 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 all right so moving on to the big one sperm count what is what are the statistics uh the trajectory of sperm count over the last 65 years 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 metanalysis and um we did a very deep dive um on the whole world's literature looking at sperm Camp um 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 up recent studies that we've done it's actually worldwide and and um and it's increasing in fact that the the in our most recent study 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 tell you that things are not getting better they're getting worse it's it's increasingly decreasing 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 nonwestern 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 wa what about what about us 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 is declining worldwide and the rate of the decline is increasing have you got any idea what countries are having this decrease at a slower rate are there any uh Blue Zone equivalents for sperm that's a great question um 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 um they've been following military recruits men you know young men coming into the military and asking them if they give a sem sample they've 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 it's Denmark they're still not doing great they still have a lot of men with very low sperm count nevertheless now Finland on the other hand which um you know used to be much better than Denmark is now going down to to meet Denmark so that's confusing because they're very similar popul 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 I'm fascinated by uh trying to map this because obviously if you could look at uh fertility rates marriage rates if you could do some um 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 uh you could I guess do surveys as well about people's beliefs uh and desires uh to get into relationships and stuff like that I would love to map uh and then and then look at what is uh very prevalent in the water what are the sort of packagings that are used what's the type of consumption Etc I would be fascinated to see how much of this Asian downturn in birth rates can be seen as um there is a particular uh brand of plastic that is exclusively used to package all meats and and vegetables and it only exists in Finland it recently got introduced to Finland and it has been in [ __ ] South Korea or whatever for ages yeah yeah yeah I I share that wish with you but um 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 um 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 um 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 the world and I'll give you the exception but almost all over the world um it's including African countries which had a very high fertility rate okay um in East Asia so we want to aim for 2.1 okay 2.1 maintains the status quo 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 Germany also not not good at all 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 you you know you get a tax credit for the child you get hungry did that thing where the the a woman got I think for three kids didn't pay tax for the rest of her life 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 a society have to to think about if we want to make maintain our existence I mean there are endangered species and and and the and humans do fulfill we are one of them 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 body's 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 con 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 U Dan has done that Dan Butner but um the um we did a study with Harvard on um a do 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 C 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 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 samples in our studies uh about their stressors in their lives in their daily lives you know 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 PR 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 um you know Saturday night five drinks six drink bad bad for your SP 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 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 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 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 sedentariness and stuff like that I'm going to guess that uh sleep poor sleep um which we are increasingly 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 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 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 were able to pick those women um you can show men the Silhouettes of women walking and the women who are ovulating men are able they they prefer that there is something in their gate design that changes based on this the stage of their ovulatory cycle so I think here this Bro Science time I think that the artificial suppression of women in men's local environment their their fertility through hormonal birth control the coil etc etc is causing men because that's another huge mediator if you were if it was me and a bunch of uh 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 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 with a t-shirt you were saying that you give a man a t-shirt from a fertile woman those are pheromones um and the the the influence of those pheromones on men's hormones and sperm count I don't know a study specifically where you know you look at sperm count in relation to but I I suspect it's there the the other thing is we do know that when the woman you have a couple the woman is pregnant his testosterone goes down because he's not he's going to be staying at home and not playing around for a while 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 need less behavior um that wouldn't so I I that mechanism works okay so we 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 on mass how much here's another one that I haven't even thought about until now how much of the uh 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 to interact with women fertile women in the environment uh 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 yeah I don't want to go so far as to say neuter but certainly alter the hormones of you're the you're the scientist I'm the one that can use the explosive language fine 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 and let's get into the let's get into the chemicals tell us tell us what we need to know okay so can we go back to The Unborn fetus and I'll tell you the story so um 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 change 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 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 is in your body BPA 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 get to draw blood and 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 shaa you should study salades okay and I said as you might if you didn't know better what salades 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 Thad s 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 valids 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 phids that we have in our bodies to rats pregnant rats early in pregnancy and what they found was what I've already told you that the male offspring are in completely 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 naturally being a epidemiologist at that time I asked what about humans because he told me about rats right 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 salaries because in the lab for the rats you gave the measured you could know how much because you gave it to the but we can't give that to people it's unethical you're not not allowed to feed test chemicals to subjects except for very rare circumstances um 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 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 Europe 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't because just gonna 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 salades in the Europe and we found them tons of them 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 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 called the thalo 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 um there are no syndromes named after chemicals of this kind no prenatal exposure produces this cluster of adverse outcomes in you know named after a chemical so here's the thallid 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 for about 50 years they had been using AGD interal distance and these other measures as measures of what they call reproductive toxicity that's part of their protocols 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 does it how do you translate that exam in a rat to that exam in a female or in an offspring of a female human so designing that protocol that exam was you know diff 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 it so we did that and public and it was a it was a groundbreaker it was huge um and it led to legislation to keep salads you know out of certain things not quite the right things because they could took them out of children's toys which is not related to Mother's exposure but anyway they were on the right track limit thid exposure and um and then other people started seeing that there were other chemicals that could do this so it's it's not just thids that lower testosterone there are other and the class of chemicals that lower testosterone are called anti-androgen okay and then at the same time a researcher in Washington state discovered that there was an estrogen influencing chemical um and that was bisphenol so you know B bisphenol 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 in this hor and that class of chemicals are called endocrine disrupting chemicals because as a class they disrupt the endocrine system so there's 80 hormones in the body so a lot of room a lot of room to defer disruption and there's like maybe 100,000 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 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 in the sperm story and in the fertility story and and what we're talking about today so that's my rant on chemicals and what you're talking about here specifically is or at least so far natally 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 they've got phalates that may be in drinking water and whatever whatever um when it comes to the culprits of environmental and lifestyle uh absorption consumption what are the what are the big movers what is it that people are exposed to objects and things uh that are are causing these to go into our bodies whether you're a mother or a 5-year-old child food I would say is the primary is number one um because there's so many opportunities we can talk about what those are um there are also um the chemicals we put on our body like skincare products makeup because they're absorbed so when 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 it right it's still it's over the other side of the room still right right they're not going to hurt you um but unless it's in your air duct or something but 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 thides particularly are put into products so they'll go into your SK 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 exactly into US 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 all of all of the above so um the um go back to the the growth of the of 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 salaries to increase the absorption of the pesticide into the plant so even you know you the pesticidal will be harmful on its own and it will also be harmful because phades are entering that lius 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 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 um milk is a great example so and I went I was at a farmers market I talked to the farmer and he's very proud of his milk he said I'm this is organic uh our you know food for the cows is organic and so on and so forth and I said great and how do you milk them you see it right I can see you're smiling you you got it so milk that's hand milked has no thads and other chemicals in it if the far if the farm was organic milk that's collected through a milking machine which has lots and tubes you've seen those pictures the milking machine all the tubes those are conveying the Thal 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 so the milk is warm the phallic 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 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 show my microwave in plastic right I mean no no no that is like the biggest known and and um yeah so I actually want to do a little study called Pharm Tork 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 well 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 mov as people can do to try and avoid uh this stuff presumably eating organic trying to get 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 life changes and things people can do either when shopping storing Etc to to maximize this 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 market 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 Su you know some places just open 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 that that'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 farmers market near you which not everyone has the Good Fortune to have you go to that farm 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 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 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 2 lit or above one liter sounds like a turn of food but when you actually look at the size of a piece of Tupperware that's on your liter it's not actually that big so go two liters or above and you know 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 absolutely the best I love that yeah are there any types of plastic that are worse or better for us let's say that somebody can't avoid uh either due to they don't have a farmers market near them uh they are battling against budget restrictions or or or whatever it might be um is there something that we can look for when we're looking at the the Plastics of the foods and and the drinks and stuff is that better and worse and how do we work that out so um silicone products are 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 th they're not going to contain the 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 um so that's that's that's that's been going on for quite a while um this thing we call wack-a-mole which is you know just swapping out you know things people don't want with things that are just as bad but has don't know about yeah they don't yet know about them so anyway um yeah if you can uh silicone is is preferable glass like I said is perfect um so uh China you know any anything that's um you know Pottery uh not lead Pottery without lead um and I 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 drawers full of glass drawers and I just use those to the I've heard you talking I've heard you talking before about the number in the triangle on the recycling thing what what is that I think that's a moving Target Chris I don't actually um ascribe to that anymore myself I don't um I I believe that recycling is um not going to solve the problem for us and and the purpose of those numbers is to get you to recycle to buy recyclable and and and you know to increase recycling but the problem is that um 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 I you know I'm I I've moved my emphasis from recycling to trying to get these things out to at the beginning you know so that we don't have to keep exposing ourselves yeah all right so uh tin I'm just thinking about some of the other places that people might consume stuff from presumably uh plastic bottles of water not good much better to get bottled water bottled water from glass uh what about those you know the very large cooler like water cooler in the office type things is that the same many of them are plastic right yeah but any plastic so there's basically there's if it's plastic assume that it's bad right that would be my assumtion still proven otherwise okay yeah okay um yeah and by the way um can I just say that there is are ways to treat water um 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 Micron nanoplastics presume that I haven't okay um so this is a kind of a new development in the field and people are um realizing that the breakdown products of recycled products and and uh disposed of Plastic Products uh are not actually leaving us they're re-entering in various forms so they're re-entering for example um in our water and in our air and they've now been found alarmingly in many cells in the body um and the the scarier thing about these is they're very very tiny um and they have two possible adverse effects and this is just under in a research stage now so grain of salt but there um they have a physical presence that can be harmful like asbestos asbestos is harmful because primarily it's physical presence and they have a chemical presence and they can um Carry with them not only the chemicals from which they were produced but other chemicals they pick up along the way so H 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 um it's I would say this is 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 on that you know it's yeah yeah so my you can tell me whether or not my solution actually works for this for years for over a decade uh I would only drink water from a a Brit filter you know like a classic desktop style filter and 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 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 um because obviously you prefer or not to pass the water through plastic um I wanted mention our 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 alternative Ro is good distillation is good filtration is complicated um in part because of the filters what's in the filters and you have to change them and you have to pay for them so y yeah yeah yeah there's two the brand that I use is uh aquat true um they're great I do need to look at what pipes are internal to the system uh but I certainly know that the the craft that it fills at the front is glass um and my solution is I have this is steel 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 uh for stage the other big one that I think sometimes is sold out sometimes isn't it's called a berky so this is a a charcoal filter like a multi-level charcoal filter thing uh and the whole thing is made of steel um so in terms of in terms of plastic I think it's made of Ste I really hope that the spout at the front is a plastic spout um but I can't remember and I don't own one but 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 berky and uh uh aquatru those are the two um for water 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 say hydrated but you know there is a world in which you increase your hydration at the cost of increasing the amount of phalates and microplastics and BPA and stuff that you're um that you're being exposed to one of my friends lives in Dubai and I went into his fridge and he's healthc conscious dude and it was just bottles and bottles and bottles of Evon you think it's high quality water held in plastic bottles so I'm like right dude I I want I really want to I was going to buy him one of those things but I don't think that they ship there so um okay one thing one of the most interesting things that I learned from you is these chemicals impact Behavior so the way the 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 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 this this is a safe space for you here sha this um 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 Pre 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 by the way 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 but um yes um in countdown this is one of the things we discuss 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 shaa the brain is the biggest sex organ in the body and um it's true that the brain is influenced by sex hormones just as the genitals are so um if you're going to mess with the estron estrogen and testosterone you're going to mess with the with the brain and specific things that we looked at was language development and so what 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 will be people that won like this again politically but females have better earlier language development and they they know if you have a child you know you you see you know how quickly they acquire words and and and and um and Men on the other hand have better spatial ability that's the joke about the you know a woman will never ask will never find her way in out of a you know a box um 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 found that the phite levels were related to the number of words the child knew or understood at age four 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 um 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 t sets or play dress up or play with dolls well first of all they did this with monkeys and they showed that the monkeys made the same choices as as human children that a male monkey will go for the car and with the car and the female monkey W and it turns out in in our study when we asked the mother about the play behavior of the child and ranked their answers as male and female the sh the male typical Behavior was less male typical in men boys who were exposed to theats so that's for what that is it's it's an suggestion I would say that exposure to these chemicals in pregnancy during pregnancy because it all happens in pregnancy um are going to affect the masculation of the brain could this change gender identity oh I knew you were going to ask that that's The $64,000 Question isn't it yeah um 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 um if you look at so I have to tell you about twins 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 like that so the the rat gets a if it's a male rat between two females he's slightly less masculinized at Birth and that's true of his HD too by the way and the female between two males is somewhat masculinized okay uterus environment that that where they're bleeding between each other right okay exactly and that's called the the um in uteral position effect and it's been known for a long time what about humans um well it turns out that when uh if you this study looked at twins in Finland and found that um female female twins were more likely to get married and had more children than male female twins so they were maybe a little less feminized if they had a male Cowin 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 co-twin of the opposite sex are more likely to be gender dysphoric so they're getting an influence they're getting some influence from their c-win so how has this been done with adoptive twins in like a pesque style how do you know that this isn't just sisters growing up with Brothers Brothers imprinting behaviorally uh social roles Theory type stuff social learning theory I not from that study but the um the brains you can look in in MRI at the brains of the male and female and you see um that there I don't have that less female typical brain development in the female that has the right yeah understood there's a a really great I I brought this up a couple of weeks ago on a podcast there's a really great um bit of data around MRI scans of 10-year-old uh 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 uh 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 you it's around about 90 it's a tiny little bit higher uh 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 but even in utro you know I I've been over this David puts who did a phenomenal uh bunch of work on this David giri as well who did a ton of great stuff on this in utero brain scans of developing uh fetuses they show sex differences I think three months old three months four months five months old you can start to see I that's you know you're a minus six-month year old I there there this isn't anything to do with socialization um sound that that that's because Chris the the time in your life that your cells are most rapidly dividing and forming or an is then it's all happening then you know in utero but I mean it it changes you know like genitals are very early and brain is later but it's that 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 uteral Period of course we talk about that a lot there's a period right after birth called the mini puberty and it's the first months of life and there's been some work showing that that period is very sensitive to environmental insults as well and then there's puberty which is another period you want to look for the periods of Rapid cell division that's that's so so puberty um and then for women in pregnancy themselves when they're pregnant and then for uh menopause there's a lot of changes in menopause so stud very little studied in menopause but but that's fascinating yeah yeah 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 I it's very hard to say because so much of it his choice now um right um so uh women couples are postponing having children and so they're the natural default is um 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 their death so um if you push women particularly into the period of lower fertility natural fertility they're you're going to have an 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 and I can't yeah yeah I understand I guess uh maybe one of the things that you could look at would be at what age do people start using um fertility treatments more sooner uh you know there should be a um volume there should just be a number of people and if there are more 30y olds or there are more 35y olds going in to use IVF or or whatever um that would be an interesting place to start but again you know I agree it's kind of circum um but 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 I now I want to tell you the exception um and that's Israel and the reason is fertility includes um artificial you know assisted reproduction births it's just births it doesn't say how they got there and in Israel um uh people are guaranteed to children by if they need it by artificial you know art art artificial reproductive technology and and their their fertility is not declined um so you know that's pretty dramatic um every other country um and and the other thing is that the use of assisted reproductive Technologies has been increasing I I can't give you numbers on that right now but it definitely has been 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 uh embryo selection for a variety of traits so you can go in with your um Harvest of 10 fertilized eggs and they can give you a polygenic risk score for externalizing behavior for autism uh for IQ for number of other things obviously it's not a perfect science but it's pretty predictive according to him uh and that's already happening I mean that that 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 where you don't necessarily you're not as restricted by Harvest you're not as restricted by a lot of different things um how well actually even before that let's let's forget the 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 what's what's your prediction 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 Sp Town infertility I don't think there's any way around it um 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 I that's ivg yeah okay right okay I didn't I hadn't called sorry yeah that's IVF IVF and I ivg is the pur poent stem cells um yeah I mean this is some dystopia if you wanted to uh some dystopian future where you have basically a million test Tu babies artificial WBS um and you can you just go to town I'm pretty sure you do it you can even do it from skin cells and stuff like that you can yeah yeah I actually you think that a woman a woman produces one egg per 28 days how many trillion skin cells are there on my upper arm yeah yeah so there's obviously a lot of scary scenarios here and a lot of hopeful scenarios and um politically particularly now with the ruling of the Alabama Supreme Court we have uh you you know what I'm talking about right um yes it's it's it's going to be even more complicated um and um 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 well don't don't forget there's a decreasing D 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 just the desire is is is also being yeah it's um it's fascinating it's it's what a time to be alive you know to be studying 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 this challenge it's 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 uh red pill which is for the anti-natalist subcultures that really don't want humans to destroy the planet and and and you know there's too many people on here in any case and so and so forth 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 a 100 years time maybe it's just it's Mormons and it's uh the the Israelites and it's uh like whoever else is I don't like whoever's whoever else is having a Blue Zone people uh and you go well that you know that's the culture that's the culture that the future will inherit because those are the only ones that have got positive birth rates and um yeah another friend here's the next level of the spicy red pill which is a friend said to me she thinks that this uh 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 Soul made it about how um uh the clergy is good because it screens fanaticism out of the gene poool um that people that are you know super crazy and I was like what I mean that's that wasn't me that was just a friend that Nam but um look Chris Chris do you have children no not yet but I can't wait to become a dad 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 in that Plastics and products and you know pan liners and food containers are taking away this option um is it's 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 and you're working two jobs and you don't live near farmers'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 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 so there's this whole social issue here too yeah yeah there absolutely is it's uh like I say just what a time to be alive and and to be thinking about these problems and sort of grappling socially with what's going on that's one of the things I'm really going to leave this conversation with is just how much of this is Downstream from reduced libbido it sounds like such a basic [ __ ] 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 the desire for relationships the desire to get out of the house the desire to leave the house to leave the screen behind cuz I'm just I just got to find someone uh yeah it's it's amazing look uh I your work is is is really fascinating and it's the uh synthesis of a lot of different pet interests that I've got where should people go they want to find out more the the book The where should they go to check out more of the stuff that you do so you can go to shamas swan. 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 countdown 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 it a group I work with and I think they're doing wonderful work to help turn this around hell yeah Dr shanana Swan ladies and gentlemen Shana I really appreciate you thank you Chris I had a lot of fun thank you very much for tuning in if you enjoyed that episode there is something else you will absolutely love right here go on give it a tap