How to Safeguard Your Hormone Health & Fertility | Dr. Shanna Swan

28:16And I used to run in Tilden Park. I suppose I'll tell it now. And there was a colony of wild hyenas, but they were behind chain links. Yes. Actually, a favorite hike of mine up the Strawberry Canyon Trail. Yeah. And I did that trail. A good friend of mine, Brian Prendergast, who's now a professor at the University of Chicago, worked on the prairie voles that were also housed at that facility. And a fun thing to do was to go see the hyenas with Steve. They're brutally dangerous animals. And Steve has tons of stories about them. We should probably resist our temptation to spiral into it. Maybe sometime I'll do a little like evening chat podcast where I tell Steve Glickman stories.

29:00He's a delightful person. Yeah. Those, let's just say this, the female hyenas have clitoris is larger than some of the male hyena penises. And those females give birth through those clitoris as we both know. So you will not be surprised to know that the female HD is longer than the male. Right. Because they're heavily androgenized. Exactly. As I recall by Andrastine Dione. Actually, I don't know that. It became popular during the era of steroids and professional baseball because Andrastine Dione was being used pretty frequently in baseball at that time. Anyway, we have to be, we could go down the spiral of but also in terms of behavior, the female is the alpha.

29:46Right. They eat first. Yes. They're physically and higher or cladominant in hyena. So it's really interesting, isn't it, that they would have a longer more masculine energy and all this is elephants. We won't go into now, but they're kind of midway in many things. So including there, they're about equal, energy and all this and males and females. Other than that, humans and other species male energy and all this is 50 to 100 percent longer. However, so three thalates, diethylhexyl thallate, D -E -H -P, dibutyl thallate, D -B -P, and butylbenzyl thallate, B -B -Z -P, are the most antigenic testosterone lowering thallates and those are the ones that were associated with a shorter indiginal distance.

30:43In males. In human males. Human males and animal. So we replicated that animal study in humans. And then, because you know this is how it is in science, I had to do it all again, right? So I started a whole new study. And that study is still going on. The children are still being followed. I think we started in 2012. The paper, first paper on indiginal general distance came out in 2005 had a pretty big impact. And so these are studies where you're looking at the inogininal distance in relatively newborn humans, then tracking that distance. No, that's a different tracking is another study. Okay, this is just two studies on demonstrating the thallic syndrome in human males.

31:41Okay, so the first one I described, the second one, the replication. And the second one is the one that's going on still. So and whether what it does to their reproductive function, we don't know that kids are only 12 years old now. So we would like to know that and we will know that. Okay, but I have another answer for you about that. So we started the second study. And the second study, which is called Tides, which is the infant development and environment study. By the way, these are both in four cities in the United States. And there we did it right. So we got the urine in the first, you know, early urine, because we knew that could be important.

32:24We didn't have that option in the first one. Remember those urine samples were accidental. We got them when we could, right? And we got repeated urins, one in each trimester to look at the effects in different trimesters. And then we examined the baby's at birth, which is what the rats. So we came much closer to replicating their rodent study. And we saw it again. I'd like to take a quick break and thank our sponsor, AG1. AG1 is an all -in -one vitamin mineral probiotic drink with adaptogens. I've been taking AG1 daily since 2012. So I'm delighted that they're sponsoring this podcast. The reason I started taking AG1 and the highest quality and most complete foundational nutritional supplement.

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33:46In fact, if I could take just one supplement, that supplement would be AG1. If you'd like to try AG1, you can go to drinkag1 .com slash huberman to claim a special offer. For this month only, November 2024, AG1 is giving away one three month supply of omega -3 fatty acids from fish oil, in addition to the usual welcome kit of five free travel packs and a year supply of vitamin D3K2 with your order. Omega -3 fatty acids are critical for brain health, mood, cognition, and much more. Again, go to drinkag1 .com slash huberman to claim this special offer. More salad exposure equates to shorter, you know, general distance in males.

34:27It was approaching the distribution in females. It sounds like the the distributions moved more closely together. Yes, yes, yes, although it wasn't the females that moved. Sorry, the male distribution became more like the female. It became more, because they feminized, but more female -like in it. But these boys also had smaller penises, less descent of the testes, smaller scrotums, so they were smaller, everything was in their general areas. All the secondary sex characteristics of puberty in males, atoms, apple, facial or growth, thickening of the vocal cords, therefore lowering the voice, etc.

35:06Are those all later activating effects of hormones, or are there precursors to those that are present in males? Because in mice, as I recall, I couldn't tell you, like we call it in the laboratory, people always chuckle at this, but it's like sexing the animals when you, you know, looked at a term that's a male or female. When they're really young, you have to look carefully at first, right? And then you get pretty good at it. As they get older, it gets easier. But when the mice are, you know, feet down, back up, you know, you can't really tell. You can't really tell. As the mice get older, their testicles become visible in the males, even from above.

35:53But, you know, as far as I know, they're not really external markers. So you may have found the one truly external biomarker of male -ness. Of male -ness. And so I do want to say one thing about females, because then that'll lead me to my conclusion about the role of this measure. So if the mother is exposed to more testosterone than expected, you might expect that her female offspring would have a more male, in a general distance. Is that the case? Yes. So it's a bi -directional. Yes. Can we also presume that if the mother either secreets or is exposed to more androgen, then the males can become hyper -male?

36:39No. I don't know what that would be. We never saw anything that would be hyper -male. So the yes I said to you was the result of a study where we looked at the girls born to women with PCOS. So women with PCOS, you know, have that excess testosterone. Paulie cystic... Oh, sorry. Paulie cystic ovarian. No, that's good. We've talked about it a little bit before in the podcast. It's associated with my understanding is it's associated with elevated levels of androgen. That's right. These women often have facial hair and, you know, the... Not just the moms, but the people, the women with PCOS have elevated androgens.

37:24Not just we're not talking about pregnant moms, exactly. Exactly. And so in our study population, we did a search for women who had diagnosis of PCOS and took that as a marker of higher testosterone exposure and then looked at the girls and yes, those girls had a longer quote more masculine intergeneral distance. What age group were you looking at? In the PCOS? In the PCOS. Oh, the PCOS was at pregnancy at the time they were pregnant. So presumably people between they're like somewhere in their 20s out to their 40s. Yeah. Yeah. So adult human females who have PCOS, we know they have higher levels of androgens, but they also have more male like androgenital distance.

38:11They do not. Their daughters do. Their daughters do. Thank you for that clarification. Their daughters. And so put this together, this measure is a look inside the womb at the androgen level that the fetus is exposed to at that time, which is amazing because you can't go in there without just you know, you can't. And so this is very early first trimester, you can't even get you know fluid and so on. So this tells you this is like a readout of what was in you know, in the fluid at the time. So then your next question was what does this mean for later fertility? Yes. Yeah. What what is the impact of this early androgen exposure to female offspring or let's just say reduction in functional androgen exposure to male offspring.

39:18The reason I'm using these you know, looped elute languages as you probably know, but for the audience, not trying to complicate things here, but a lot of the masculineizing effects of hormones in fetal development is actually testosterone that's converted into estrogen. So it can get pretty tricky. Right. And but maybe for sake of simplicity today, we'll just stick with androgen effects on masculinization with the understanding that some of those effects are the consequence of testosterone being converted into estrogen. It's just that people form such strong associations falsely that you know testosterone is male, maleness and that's not true and estrogen is femaleness and they both and it just gets really murky.

40:02But for the time being, you identified an external biomarker of fetal androgen aka masculinization via the mother. That's right. Got it. Okay. So then we asked the question you've asked and many people asked who cares? What why would we worry about a boy having a slightly smaller anal gentle distance? Well, I can tell you there are many boys that are probably worried about it right now. We've probably got the ruler and the calipers out right now. We just you know, but I'm going to answer that question. Right. So I told you that our kids are too young. They're not producing sperm right now. Right.

40:53So we had to go to an adult population. Right. And so we went to a population of college students in Rochester, New York. And what we did there was was make an assumption which is based on animal data. It's true in animals. We've been following the animal path here all along. So in the animals, my colleague Earl Gray who did these studies. His name is Earl Gray. Yeah. That's cool. Yeah. He said, A -G -D is forever. In a general distance is forever. Now what that means is it's not like your anal gentle distance today is what it was when you were born. Of course, you're a bigger person. But that means adjusted for body size.

41:40Right. So if you assume that A -G -D is forever, if you're born with a short for your size A -G -D, then when you're 20, you'll have a short for your size A -G -D. Okay. Can we use in that? Okay. So if we assume that, then if we get these college students to come in and we can measure their anal gentle distance, we're getting a reflection of what it was when they were born. Okay. And then we can get their sperm count. And then we can see if they're related. And that's what we did. So we got this population of volunteers, paid them $75. And one of the guys said, for 75 bucks, you can do anything.

42:25And so what we did was we measured their anal gentle distance. And then we got them to give us a semen sample and complete a questionnaire and things you do in a study. We'll link to that study. But I have a couple questions about the controls in that study. Just for sake of people understanding how a study like this would be done. I don't expect you to recall all the details. But you're adjusting for body size and body weight. Yeah. Height weight. What are the factors that would scale here that would allow you to normalize? In other words, what you're trying to do is backtrack to what it likely was at at Lymphs.

43:01No, we didn't actually try to go back. Let me just tell you what the results were. In this group of men, if they had a longer anal gentle distance, they had a higher sperm count. Got it. So you were correlating those two measures. Right. And then if we wanted to say something about we didn't try to say anything about how it was when they were born. We just said, okay, we'll take that assumption that this reflects their early AGD. If we want to say something about early AGD and sperm count. So it's easy to say AGD is related to sperm count because we measured that. We saw that. A correlation. That's published.

43:42Okay. If we want to say there are early AGD births and there's sperm count, that's a leap of faith in some sense because we don't have there early. For these guys in Rochester, we didn't measure their AGD births. Were there any conditions of being a participant in the study such as refraining from alcohol, cannabis, et cetera, in the 90 days prior, 90 days being the duration of us per mad genesis? Yeah, I don't remember that. These are college students who presumably someone with them are dreaming. Okay. But in the end, it was a robust link. And then Mike Eisenberg, who you might know. Yeah, my colleague at Stanford, he's been on this podcast.

44:21Yeah. Yeah. Good, good. So he's a colleague of mine too. And he looked at men in fertility clinic and those who had born children and those who had not born children. And the men who had born children had a longer in a general distance than men who had never born a child. Never born, but we're trying. Yes. Right. These were not people who opted out. Exactly. These were people who were who were having challenges with fertility versus success with. Yeah. And by the way, you know, the question of how you measure AGD in an adult man is a different question than how you measure it in the newborn. And we did a lot of work on that and Michael helped with that too.

45:02So it sounds like Oh, and they ask were the sperm counts that were on the let's just say the lower like the lower quartile were the quote unquote lower sperm counts like functionally lower because I always wonder about this like it's come up in a number of discussions like with Robert Sapolsky with Mike Eisenberg and now I'm asking you, and when we hear that sperm counts are going down, are they going down to the point where fertility is is impacted? That's really the one of the I think functional questions. So I'm going to let's lay aside the question of AGD, right? That's not really interesting, but let's talk about sperm count.

45:44Okay. Okay. So if you there's a beautiful study among pregnancy planners out of Denmark quite a long time ago. And in that study, what they did was take couples that were trying to conceive that had never or not recently, I can't remember, used oral contraceptives. And then they saw what the sperm count was and how long it took them to conceive, right? Time to pregnancy in relation to and what they showed is a really interesting curve which has never been corrected to my knowledge. It's what I use and what I think people use, which is that if you, I wish I could draw it here, you should have a board and what part of it.

46:35The problem is a lot of people are listening, but maybe we can talk people through it. So just think about a curve where you go all the way down to zero that would be no sperm. And then as the probability of conceiving is zero. So you're looking at sperm count along, you know, is the x -axis and months to conception. And what you see is that if you have no sperm, you don't have no conception. If you go up to around 40, 45, there's a steep increase. So the more sperm you have, 40, 45 million, million per milliliter. And this is million per milliliter. So just pure concentration, not number of low -tiles sperm.

47:19This is just how many sperm? We're not talking about quality. We're just talking about number. And when you have 45 to 50 million per milliliter and below, it matters a lot what your sperm count is. I mean, people say it doesn't matter. Yeah. If you get in this range where the probability of conception is dropping off really rapidly, it matters a lot. And then there around 45 to 50 starts to level off. And then after that, after a certain amount of 100, probably 75, it doesn't matter at all. So 100 million sperm per milliliter of semen. Yes. So can you see this? So when people say does sperm count matter for fertility?

48:04Yes, it matters a lot if it's low. And no, it doesn't matter at all if it's high. So we just have too many sperm. I mean, I don't think human is, you know, and there's nature runs a probability game overproduced sperm. Right. Some of those will be high quality. Some will be low quality, depending on their age when they were, that is when they were generated or their conditions, you know, or their conditions is how much heat exposure, etc. So nature runs a probability game. That's right. Hoping that the the best quality sperm will fertilize the egg. Right. So below 45 ,000, excuse me, below 45 million per milliliter.

48:46Below 45 million sperm per milliliter of semen, the sperm count really matters. It drops off precipitously. That's right. Once you get up to 75, 100 million per milliliter of sperm, then you're good to go. Right. And sperm counts range anywhere from, you know, it could be low 8, 9, 10 million per milliliter in the very low situation. It could be zero in some people, right? All the way up to 400 million. There's a huge range. That's right. And that's a function of age. It's a function of genetics. It's a function of presumably thalate exposure. Yeah. I'd like to take a quick break and thank one of our sponsors, Function.

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51:05Again, that's functionhealth .com slash huberman to get early access to function. We were on to the fact that sperm counts are dropping. There's a relationship to analgenital distance, and there's a relationship between analgenital distance and thalate exposure. Then I asked the question, we're hearing about sperm counts dropping, but is it functionally relevant? Is that one of the reasons why fertility is dropping? We've also got the female side where we've got women with elevated androgens. We can talk about that a little bit later. Then of course, we have the sociobiology piece where people are opting out, or it's also economics, in some cases, opting out of having kids.

51:51Let's go back to sperm count, because we haven't really talked about that. It's a different path, and my introduction into thalates was not through sperm count. It was through this question of my colleague asking me, you should look at this and challenge, and I looked at it, and that was really, really interesting journey that I went on. But there was a separate for a while journey that I was on, and that started in the late 1990s, when I was asked to join a committee of the National Academy of Sciences. That committee was assembled to look at the question of whether formerly active chemicals, endocrine disrupting chemicals, in the environment posed a threat to human health.

52:42Because at that time, it was like, well, yeah, we hear about this, but should we care? And so that committee wanted to consider a study that had come out of Denmark a few years earlier, which claimed that sperm count had dropped 50 % in 50 years. Wow, that's a huge drop. That's what we're seeing worse than that, by the way, now. So, okay, they said to me, I was the only statistician on the panel, would you look at this and see if we need to consider this in our deliberations? And as I mentioned, I'm skeptical, and I looked at it, and I thought, I don't think so. That was my initial reaction. And that was because, first of all, I didn't know who had written this.

53:33I just saw it in that journal, and it was not very big, and not for many figures, not very much data. And I thought of it, and I thought, that's a big claim for a little, a little paper, you know. But I'll look at it, because it's important. And so, what I did then was to think about all the factors that we epidemiologists call confounders, things that might have caused that decline if it wasn't real biologically. And so, we could think of some of them together, maybe the method of counting sperm had changed, so that later methods counted fewer sperm in the same sample. That's certainly possible.

54:21But it turned out that wasn't the case, because they actually had all used the same method. And maybe the men had changed, you can't get a sperm count at random, you have to get somebody to volunteer. So, who were these men? Where they're very different in the early part of the study, in the late part of the study, in a way that maybe in the late part of the study, there were men with lower sperm count, and they were more concerned. You know, maybe they were more obese. That's pretty possible. Obesities related to sperm count fertility, and maybe they smoked more, and maybe, and so on and so forth.

55:01Right? So, what I did was to get the 61 studies, go through them, and try to extract information on all the factors that could explain the decline. So, I created a multivariable model, and ran that model, into my astonishment when I was done. The slope of the decline was exactly the same to the first decimal place. It had not explained anything. I was like, oh my god, this looks like it might be real. And for those listening, what Dr. Swann is describing is being the excellent scientists that she is, she went and looked for all the things that could impact the result that were not related to what the main conclusion seemed to be, which is that sperm counts were going down over time.

56:01Right? And this is really important, because I think what we're talking about here in parallel to the main conversation is how to do really great science, especially in human populations that are out there living, you know, some of these men probably, you know, smoked some cannabis. I'm not saying that reduced the sperm count. It might reduce sperm mortality. However, we covered that in the podcast. Now that all the cannabis folks go, well, you know, so and so got so and so pregnant when they were doing it. So I mean, a lot of weed and I always say, okay, well, there are a number of other factors, right?

56:32You know, but alcohol, there's frequency of ejaculation, right? The requirement to abstain for 48 to 72 to hours to up to five days prior, you know, et cetera, all these factors that men may or may not faithfully report, but you assume that if some are telling the truth and some aren't that there's an equal distribution of that. So all the different things, right? This is so very different than looking at, for instance, ovarian reserve, like the number of eggs where you use ultrasound and you use AMH levels and sure things can impact that, but it's a little different than when taking sperm counts.

57:12So thank you for doing the study so carefully and for repeating so many times. I mean, many of the studies that you've done are, or you've done follow -up on the sperm count studies across multiple years, you know, as you said, the first study was in 1992, then you did one in 2017, then there was one again, and there was an update I noticed online. So you are extremely thorough. And it probably reflects your early training in math and statistics and probability theory. You're not somebody to just kind of go in and go, oh yeah, like in these people that eat a few too much of this, then there's a little less of that.

57:47So I just wanted, if today's discussion feels like we're really, we're laving through this, that's intentional. And it's important for people to hear these kinds of claims are not the sort of thing that you could, people make them all over the board, but work like this needs to be done with an extremely meticulous eye and consideration of all the variables. Well good scientific method. Yeah. Yeah. And I would say especially with human epidemiological work, because of the number of potential confounding variables. Right. Right. So when I saw that and actually did another study to select my own studies and not accept her 61 studies that had been published, that Elizabeth Carlson had published.

58:32So new studies came up to more recent times, went back further, did it again, found exactly the same thing. Okay. So there were three, you know, three looks at that. And I thought, okay, I'm going to accept this now. This is sperm count is declining. And why? I turn to the why. Okay. Because up and down now, we hadn't said anything about why. We just said, is it doing that? Yes. Okay. If it now, we believe it is declining, why? And so then I thought quite a lot and talk to people and ruled out genetics because it was too fast. It's two generations. It's too fast. 50 years, two generation. So if it's not genetics, then it's environment.

59:14And so what is it about the environment that could do this? So I asked, okay, in the environment, there could be things that are making sperm decline. So if you think about how you might look at that, you might design the study that I design next, which is another study. And by the way, this preceded the AGD. So we had four cities in the United States that we picked with different environments. And then we got man to come in and we used the same equipment at each place. We used the same method of selection, selecting the man. The technicians were trained centrally at UC Davis. We had very good quality control.

1:00:01So samples were sent around every quarter to make sure that everybody was measuring things the same way. We didn't want drift, right? And then we got their urine. And that's how I had those urine samples. So what if you wanted to do this study and you wanted to get a representative sample of men, where would you go? Because you can't, I can't ask a guy in the street to give me a semen sample, right? I mean, it's not something you get very, you know, so I thought, how can I get a representative sample? And which would teach me something about a larger population, called the parent population. So here's a sample.

1:00:39It should represent the parent. So how do I ensure that? And what I decided was to sample partners of pregnant women. Because pregnant women all come to medical care almost all. And if their partners will give a semen sample, then we have a representative sample. And we know what we're looking at. So that's what we did. So this is a, the semen study is the study of partners of pregnant women. And, um, and of course, they'll have slightly higher semen quality because they got their partner pregnant. But, um, and so we had their urine, we had their blood, and, um, we looked at their semen quality.

1:01:23And then we decided to look at pesticides. And the reason we look at pesticides was because there was a lot of gradation across our four centers in pesticide use. And what we found was really extraordinary that men who were living in central Missouri, where I was living at the time, who were in the middle of an agricultural belt, where there was spraying all the time for soybeans and so on. Um, those men had half as many moving sperm as men in many apples. Whoa. Whoa. Huge, right? And then we went one step further. And within Missouri, we looked at a sample of men who had very high sperm parameters and very low sperm parameters and showed that five pesticides were significantly higher in the men with the low sperm parameters.

1:02:23That include motility, morphology, you know, all the ground. So these are pesticides that are being sprayed in the air on crops. You mentioned soybeans. What are what are other types of crops? I don't know. Okay. I don't remember. So, so plant and fruit crops. Oh, it was, yeah, whatever, whatever they were growing in Columbia, Missouri at that time. And just to make sure I understand that it's not that the men need corn and soybeans. Corn and soybeans. But we're not talking about eating corn and soybeans. We're talking about living in an area where pesticides are being used by, I guess it's still called dust crop.

1:02:58Yeah, we didn't go into how they got these. We just looked in their urine and there were the metabolites. The metabolites don't get in their urine unless they were exposed exposed through the air exposed by eating corn and soybeans. We don't know. We don't know. Okay. We don't know. But this was not particularly, you know, waiting in the sample farmers only or anything like that. So whoever came in to the, remember how we got these men? Their wives were pregnant. They were having prenatal care at the University of Missouri. So that's where we got them. Whoever happened to come in to the prenatal clinic and agree to be in our study, they're the male, you know, urine, males urine was measured for, for these pesticides.

1:03:38I'm sure a number of people including myself are wondering in what other products are these five pesticides present? Are these commonly used pesticides or is it something about... They were, they're called the triazine pesticides. The atrazine was the most widely used and it's huge use around the world. I mean, it's highly, you know, one of the most largest commercial pesticides. So these were very big players in the pesticide field. A relevant theme there would be maybe we could take a moment and talk about atrazine and its effect on male sexual behavior in amphibia. And we'll come come back to the sperm say because when I was a graduate student at UC Berkeley, I had the wonderful experience of taking a course from the now, I think you mentioned he's A -Deen.

1:04:33There are multiple deans on campuses. Tyrone Hayes is a wonderful researcher who established a link through his research between atrazine exposure and male sexual behavior of amphibia. Could you elaborate on that result? Yeah, so Tyrone first caught frogs in the wild and environments that were more or less exposed to atrazine and showed effects on development and sexual behavior. Then he in his lab, he actually exposed them. So he knew exactly who was exposed and how much and he showed that the, I can't tell you what percent or what, you know, but a significant number of frogs exposed to this pesticide atrazine chose to mate with other male frogs.

1:05:27Tried to mate with other male frogs. Presumably unsuccessful. Well, they mounted them. He has photos of the male, male's mounting males. And so presumably this is a neural change that occurred. Neuroendocrine change, but ultimately neural since mounting behavior is controlled by, actually we now know that the hypotherlamic nucleotide that control this David Anderson who's been on this podcast has people in his laboratory that, including a former graduate student of mine, working on this specific issue of what the circuitry is, that's a remarkable result. It's been kind of, you know, used and misused out there in the media and in popular culture.

1:06:14But if nothing else, it suggests that the organization of the neural circuits and neuroendocrine pathways that control sexual, I don't want to say partner because he's meeting thing that frogs aren't monogamous, but sexual preference are significantly impacted by this atrazine. Yes. And it suggests that there are other environmental chemicals as well. And we, I don't know how, we'll have time to go there, but I did work on neurodevelopmental outcomes in relation to brineal phallate exposure. And so I think the overarching idea here is that the brain, like the genitals, is sexually dimorphic. And there's many people, by the way, who will take offense at that.

1:07:07Really? Yeah. I think there's, I mean, going back to the work of Frank Beach in the psychology department at UC Berkeley showed this in Beagles. It's been, it's been shown in pretty much every species. And I'm just gonna tell you that, but it's not a better worse. I think this is what people need to hear. Like dimorphic does not mean better worse. It means different. Right. Right. And that there, and there are, for example, advantages to spatial reasoning in a male, which are related to testosterone. Right. You know that. I mean, I think there, yeah, I mean, my understanding of this literature, and I'm not an expert in this particular aspect, which is the behavioral phenotypes.

1:07:48But, you know, like the meteoropreoptic area of the hypothalamus is known to be sexually dimorphic, depending on testosterone, converging to estrogen during development, et cetera, et cetera. And there's just so much evidence of this. How it links to behaviors is, can, I think, can be reasonably placed into, um, ethylogically relevant, um, evolutionarily logical arguments when talking about rodents or beagles or even racist macaque monkeys. I think where people get, um, a bit inflamed is when people try and take the sexual dimorphisms that have been observed in animal brains or in even in human brains and tack those to specific abilities or, or, or lesser abilities.

1:08:34I think that's where people sort of go, wait a second. Like I have much better sense of direction than my husband. And you go, well, yeah, like, you know, and then you go, well, does that mean that she has higher testosterone than him? And then maybe in that, and pretty soon you're, you're in, uh, I'm almost at no man's land. I know person's land of, of, of, of confounding variables. Right. But I really appreciate that you raised this. And also that you said it, and I didn't, because I feel safe for that way. But look, there is a very simple, outdated question error. And it's play behavior. It's called the PSI.

1:09:09It's been used for years. Have you heard of it? It's a rough and tumble play. Yes. Yes. And there are 24 questions on there. And they are sexually dimorphic, I guess you could say that there, you know, my child likes to play with dolls. My child likes to play dress up. My child likes to play rough and tumble, uh, et cetera. And we gave that questionnaire to our population, um, and looked at the answers, uh, that the mothers gave, both in our population, by the way, and a Swedish population of the colleague, their, uh, Carl, uh, uh, born a hug and Gustav born a hug. And, and, um, what we found, higher thalate levels, these anti -androgenic thalacs were exposed, you know, we're associated with less masculine male typical play in our male boys.

1:10:06So, this is thalate exposure to the mom, baby is born in the young human child. Yeah, four, four, yeah, four years, four years of age. Four years of age, less rough and tumble type play. That's right. Among the boys whose mothers were exposed to more thalates during a critical period of development. Now you can see that's some politically loaded issue now. I mean, you know, yeah, well, I think we're, I mean, let's, let's, let's have some fun with this in, in, in the scientific sense. The notion of dimorphism is, you know, okay, male and female brains are different, right? Which I, and male female defined, and those, almost all those studies as presidents of a Y chromosome.

1:10:48And then people say, well, there's some, there's X, Y, Y, and then there's X, X, Y, okay. But most of the time you're talking about X, X chromosome or X, Y chromosome is at birth. Forget everything else for the moment. These are always distributions. This is what I think people need to know. We're not talking about, these are not, this is not, you know, two hills of data separated by a valley. These are overlapping distributions, right? So you get males with a quote -unquote female -like distribution, you get females with a quote -unquote male -like distribution. And I think as long as we acknowledge that, then we're just talking statistics.

1:11:24We're not, we're not placing any cultural or any value on it, really whatsoever. But is it, but if you, you could make the analog to the intergeneral distance, it's kind of similar. You know, you have the same exposure, salad exposure, you have something changed statistically. We don't see huge differences in the boys' genitals. And, and we don't see huge, I don't, we know, these kids have not been scanned, so we don't know how their brains look, but based on their answers, we don't see huge differences. We see tendencies, we see they are more likely if they had been exposed to these salads to want to play dress up and have tea parties.

1:12:04More likely, doesn't mean that they're all going to, but that's the direction and so on. So I think we have to just think about more likely, not absolute. Yeah. And of course, there are also the sociobiological variables such as if a young boy has a sibling that's a sister, there's more likely to be dresses around, right? She's going to, yeah, if he has two older brothers, there might be more rough and tumble play happening in the house. And I have some friends that are women who have older brothers and those women are, you know, some of them roll jujitsu or do, you know, and I know some women who are only children who do martial arts and fight, right?

1:12:45Yeah. So I think that none of this is deterministic as we know. But let me just add, we did control for the sex of the sibling, older sibling, and we also asked about the parents' attitude just towards same sex play. So how would you feel if your child, your male child played with dolls? Would you be discouraging? Would you incur, because it has a lot to do with what's in the house? You know, if you say, did your child play with dolls? Well, what if there were no dolls? This is super interesting to me. I don't want to reveal too much, but I grew just because it's not, it's just an end of one, but I grew up in a household where I have a sister, but then after a certain age, I received very strong messages about what sorts of play were gender appropriate.

1:13:34And I think I also just naturally defaulted to, there were a bunch of boys that lived in my neighborhood. They had older sisters. So all the sisters hung out together. It's kind of interesting. All the younger brothers pretty much hung out together. And the guys that weren't didn't have siblings or had brothers for siblings. So there was a really strong divergence, but I grew up in the set that was in the 70s and early 80s when things were, let's just say culture was more dimorphic then. Clearly, I mean, there were television shows like all in the family, which the entire basis of the show was the wife going back to work and the husband being confused about.

1:14:04I mean, nowadays people will go like, what? That's why I have to ask is I know people are wondering, and I'm wondering, what are some non -pesticide sources of phallates that we have agency over that we can take control over? Right. So let me correct you. It's not that sources of phallates necessarily pesticides. There are phallates in pesticides. But that's not the worst player in the story. If you look at the different classes of exposures that are homonally active, right? Pesticides are, phallates are bisfinals, like this phenol A, BPA, certain metals are, there's the PFAS chemicals, all these different classes, right?

1:14:59And if we want to go into what in our daily life exposes us to these things, that's another story that we can talk about. But they're going to be different depending on the class, right? So let's throw our arms around all of those for the moment. And I'll just ask you, given that you're an expert in this area, what are the top three to five sources of endocrine disruptors that we have agency over? And let's forget about pregnancy for the moment since we're all out of the womb if we're listening to this. Some people will be pregnant as they listen to it. But would you say it's, you know, drinking out of plastic bottles?

1:15:47Is it laundry detergent? Is it, you know, rubber tires that are cascading down on us through the air and we're inhaling them? I mean, presumably all of the above. But what are, which ones that we have agency over? Do you think are the most, let's just say concerning where people could make better choices? I would say foodborne exposures, exposures in the food, in the food packaging, in the food storage, in the food, in the cooking utensils. We can go through the various things, but we're doing that all the time. We're eating all the time. We're getting food into us and these are bringing in a very, you know, in a way that we have some control over some agency over, you know, we can make changes in our foods.

1:16:44Very close to that is drink, you know, food and beverage.

1:16:52So I, first of all, I've talked about this a lot. I've written about it in my book. I'm also, as you know, involved in a movie where in the movie, that might be a good time to talk about that. What, what we do in the movie, the movie is about six couples that are infertile. Okay, they haven't been able to conceive in 12 months, that's the definition. And then a company that I work with, a million marker out of Berkeley has a trained staff that interviews them, not only them, but anyone who signs into this company, interviews them and ask them what they use. What do they use for their facial facial care?

1:17:35What do they use for their shampoo? What do they use for their cleaning products and their laundry detergent? And they're, what do they store their food in and on and on and on. So this is long inventory that they take of all products that people are aware of using. Okay. And based on that, we identify likely bad players in the list. So how we do that is another, you know, we can talk about that later. But then in the film, and in this little, it's actually an experiment that I designed and were called an intervention. And we are then intervening in their exposures by changing out these things that they told us.

1:18:20So we will tell them, you know, don't use any product with fragrance, for example, that's major source of exposure to salads. Any product. Any fragrance products. No perfume, no lotions, soap with fragrance. Even essential oil fragrances. A essential oil is a tricky mix. It's a mix. Yeah. So I'm going to, that's guarded. But, but anything, you know, spray deodorants, roll on deodorants, laundry detergent, shampoo, and any, if you can smell it, it's probably affecting your hormones. I'm so happy about this answer, not because I have any stake in any company related to fragrance free stuff. But I, I have a very strong sense of smell.

1:19:03And I, either love or hate smells. And I hate synthetic smells, like going through the duty free, especially in a European airport, where it was all the perfumes. And I'm just, I was going to hold my breath. It feels like I'm breathing poison. I know. Well, you are actually. Yeah. Yeah. Yeah. And most soaps, right? Yeah. Super interesting. So that's your primary intervention is to tell them get rid of anything with fragrances. No. That's only one thing we get rid of. So then we, we talk about how the plastics that they use to store their food, food storage containers, try to get them to get rid of those if they're made of plastic.

1:19:43We try to get them to get rid of their non -stick pans because of the PFAS chemicals that are in those. And, and so on and so forth. So we go through all steps of their life and try to tell them how to make changes that will reduce their exposure. But presumably also changes like if, if the man is obese, for instance, you might have him walking a bit more. No, you don't touch any of that. Well, you see Andrew, if we did that, we would be mixing up two interventions. We would be mixing up an obesity intervention. I see this is a study. I'm sorry. I thought that this group is is mission with helping couples get pregnant.

1:20:20No, no. This is how this is a study to look at what happens if you make these product related changes. Great. Just product related changes. Exactly. Love it. Exactly. We would love to do and probably will do another study separate one on obesity. And you know, a lot of these chemicals just to let you know our obesity. They increase obesity. There's a book out called Obesigins. You can read about them. And so you know, it'll be it's very, you know, there is some overlap. So by reducing some of these chemicals that are in your food storage containers, you're also reducing obesity. So it's not a clear, you know, yes, no.

1:20:57We gave them a box each couple. I went to their house. Six couples around the United States with a big box. And in this box are these alternative products. And so you know, straws and bamboo spoons and you know, $500 per box. I think it was approximately it had to do with their personal, you know, exposure. And and then they made these changes. Now, unlike another study that you reported, they are at the end quite happy to keep doing this by the way. They love this. They love doing this. It was so gratifying to see that they felt in many, many ways their life got better. You know, I'm not a I'm pretty careful in what I so I hesitate to say this because the data is not hard, but the impression is that they are happy, happier.

1:21:57They're sleeping better. They report more energy and so on and so forth, having made these changes. We need to follow that up with hard data. I'm not writing that. I'm not, you know, but that they, but I can say and I can write that they felt very positive and are we're going to go back and see if they did continue. We need to do that. But at the end of the six of the three months, they and hopefully in six months, they will, they are still making these changes in their lives. Did you collect data on whether or not they were able to conceive after having made these changes? Yes, we did, but I actually can't talk about that until the babies are born just kidding.

1:22:36And we did get their sperm count at the beginning and the end and then had some very interesting data on that which is really to report to earlier. Let me ask you this then. I appreciate that the not wanting to share specifics results until the all the data are in and it's published. If somebody listening, we're having trouble conceiving for 12 months or more are the sorts of replacement intervention and product interventions that you're talking about here. Things that you would at least feel comfortable saying would might be a good place to start or to explore. Absolutely. Absolutely. There's no harm.

1:23:19You know, we're none of the changes are putting people at risk or doing anything that could be harmful to them. I'm sure of that. We're very careful. And some are going to be cost saving. I think that's what like drinking out of plastic bottles far less if at all. Just for reasons related to wanting to reduce waste, I use a mason jar or use these or ceramic. Although you'll probably tell me that the lining on the ceramic mug might have endocrine disruptors. No, okay, great. Well, that'll keep drinking. But it's very reassuring to me that there are things that we can do in terms of cost saving elimination or replacement of consumables.

1:23:59Buying and bulk. That can improve endocrine status. Maybe fertility also. In bulk. Bring a container to the store and fill it up a glass jar instead of buying something in plastic. You're winning on both ends because those bulk products are cheaper. One of the things I did with the couples was go shop with them. And we went around and we looked at various products. And for example, we looked at the produce and there was option to buy free standing bunches of letters, heads of letters or wrapped up in plastic bunches of letters. And I said, let's compare the price. I actually didn't know. But the free standing unwrapped letters was cheaper.

1:24:39And I think that's, you know, because that makes sense because there's a work involved in wrapping it up and in the container and so on. And so not only are you getting something that's more toxic, but it's more expensive. When it comes to reducing BPA exposure and some of these forever chemicals that you mentioned, seems like reducing fluid intake from plastic vessels is going to be number one. The primary source of BPA is in the lining of cans. So any drink or soup or anything that comes in a can is going to be any can, all can, unless it's a high end, you know, elite company that's made the change from BPA to an alternative lining.

1:25:30And they'll say that. So and by the way, BPA has some bad relatives such as BPS and BPF and maybe you'll be interested in this story. So when it came out that BPA was estrogenic, which is what it is. And by the way, it's kind of the evil twin of thalates because thalates are anti -androgenic and BPA is estrogenic and thalates make plastic soft and BPA makes plastic hard. You don't want either. Okay. So when this came out that this was a bad thing, the manufacturer started selling things that say BPA free. I'm sure you've seen that. The trick is that instead of BPA, they use BPS and BPF. And these are chemical, these are look -alikes, they're analogs and they're just as harmful.

1:26:23Sneaky, sneaky, sneaky. I'm not a conspiracy theorist, but it's just so dirty. It's so dirty. It's like it's, you know, right now is a really important time to be having this discussion because there's been a lot of movement on Capitol Hill and there's been a lot of movement on social media about trying to call attention to metabolic syndromes and highly processed foods and issues like this. And it's become unfortunately politicized. I mean, I hear this stuff and I just think to myself, the only good faith that we can really trust is our own desire to be healthier and to have our families and friends be healthier and to try and consume and not consume things on the basis of that.

1:27:06That my belief is that we can't trust any larger agency to either protect or harm us. It's like it's not, it's like they're going to do what they're going to do. We just have to be informed. As opposed to trying to dismantle the systems that led to this, which just seems like infinitely complicated. Maybe you can do that, but I'm far less optimistic and now that I'm 49 years old, I can say things like now that I'm 49. I feel like, but what you're saying is really important. If I look at a can, it says BPA free. It doesn't mean anything because it has BPSs or other endocrine disruptors. Right. So drinking out of glass vessels, drinking out of ceramic vessels, metal, but not cans, not metal cans, not aluminum cans.

1:27:52Right. Not cans now. Goodness. Okay. You know, you can get a metal water bottle. It's not lined with the steel steel. Yeah. And is it true that microwave safe means it just means that the plastic won't melt in the microwave, but it's you never, never put plastic in a microwave. So here's the story. The BPA, salads, plasticizers are added to the plastic, but they're not chemically bound to it. Okay. So if you put anything in a container that has these chemicals in it, they will and then put it in a hot environment, they will come out of the plastic and go into the food. So if you in a microwave or you put your bottle in the car and the sun comes in and it warms up the bottle and then the stuff goes into your water, you don't want to mix these chemicals and your food.

1:28:55But if you do, the worst thing is to do it in a heated environment. I think about the food that was consumed in college in the in the 90s and 2000s, like the cup of noodles with the styrofoam, the, you know, things in packaging. Stuff like that is pretty straightforward to eliminate once one understands and decides. Then we start getting into the more nuanced thing of like, okay, you can buy a really nice tasting anyway, grass -fed, grass -finished steak, but it's in plastic. Well, or you can go to the butcher, but most people don't have time to go to the butcher. Or you can get strawberries at the farmer's market, blueberries at the farmer's market, which is what I try to do, but sometimes I buy strawberries at the market and they have those plastic flip tops.

1:29:41Things, and of course I recycle the plastic. How bad is it if you know, you rinse the strawberries off with good clean water that we're in the plastic container? Are you - We have to do that experiment. I don't know. Yeah. So I guess - So it sounds to me like not drinking out of cans, not drinking out of plastic bottles. It's going to be not microwaving plastic ever. And in general, just avoiding plastic intake. If you can afford it by organic, so you're going to avoid the pesticides and then thalates are actually added to pesticides. And they're added because they increase absorption. So you know the - you want your pesticides to get into the plant, right?

1:30:23And to kill the bad stuff. And insects. And - And so the same property of thalates that makes them good for pesticides also makes them good for our hand cream. Just mentioning absorption, absorption. Anything that's absorbed in the body is going to have thalates in it. And it also holds scent and color. So it's added to those scents. And it's also added to your lipstick and to your color, you know, whatever you put on your face. And so on - anything that holds scent and color, that's going to be thalates. Sorry. I've been accused online of being a sunscreen truth or - I'm not a sunscreen truth or I'm going to keep repeating this as many times as I can.

1:31:08I - I understand that UV damage to the skin can cause certain cancers. I get that. I agree with that. The data are pretty clear to me, based on having researched this pretty extensively and talked to many, many people including Dermont and Colleges that mineral -based sunscreens like zinc oxide and titanium dioxide. But certainly zinc oxide are safer than the chemical sunscreens. A lot of people get upset when I say that and they say, well, in Europe, there's tons of evidence that the chemical - based sunscreens are in or save it. Okay, fine. You use them. I'm not going to the point being that UV damage is bad.

1:31:46There are ways to protect ourselves from the sun, including physical barriers like clothing hats, etc. But pretty much all sunscreen that I'm aware of is designed to be absorbed. So what do we do if we want to get some UV protection from whatever kind of sunscreen we deem say for ourselves? But we want to avoid these exposures to these other things. What do we do? Do we have to hunt really carefully for the right sunscreen? Yeah, I think that's a good idea. Are you familiar with environmental working group? Is another one out of the Bay Area? No. Okay. I don't know actually where they're pretty big.

1:32:27Sounds sounds familiar, but I can't say I'm familiar with that. So they have consumer guides. And in those consumer - so environmental working group, I'm not part of them. I'm not, they're work. And in these consumer guides, you can put in the product and they have categories. You can put sunscreen if we have time we can do it right now. And then you can put the name if you're sunscreen and it'll give you a number. And then if the number is less than 10, it'll tell you why. Are they independent of any fun funding? Yeah, that question will probably come up for you too. People will say, where does she get her funding?

1:33:04People get very suspicious about this. I can tell you. Yeah, that would be great. Yeah. So I am a tenure professor, Mausine. I get some salary there because I'm only part time. And I have a funder, one funder who funds, found, funded my sperm decline, second sperm decline analysis and the publicity of my book. So he's a, he's a, it's a foundation. I won't. So it's philanthropy? Yes, philanthropy. Yeah. And it's actually not a lot of things. So no, and so there's no reason to think that anything that you're telling us is linked to like the food industry or an alternative product or anything. I'm very, very careful not to endorse any product because I don't want that complication.

1:33:48Yeah. Thanks for clarifying that. I wasn't, I wasn't suspicious. But, but I think nowadays people have just been taught to, you know, appropriately. So they've been taught to say, well, wait, where does this funding come from? Because a lot of the studies about the, that led to the food pyramid, for instance, people were under the impression that somehow that was biased by, by companies that were funding the work. And I don't know, I haven't done the forensics on that. I don't have the time or the energy. All I know is that when it comes to what people eat, when it comes, when it comes to what people put on their body, it becomes a very personal thing.

1:34:24And it's woven in with a lot of psychological and emotional issues. Yeah. Yeah. Yeah. Okay. What are a few things that you do and or avoid in light of what you know about these endocrine disruptors? And by the way, it goes without saying that you're in spectacular cognitive and physical shape for any age, but it's, it's really remarkable. I, I feel comfortable sharing this because someone else published it online recently. You are soon to enjoy your what birthday? 89th. 89th birthday. Amazing. And with all the talk about longevity, cognitive and physical longevity, everyone's thinking, including me like, what does she do?

1:35:08Well, she avoids all these endocrine disruptors. And she has a wonderfully rich life of curiosity and other things. But yeah, what are some other things that you do end of, end of void in light of what you know for which there may or may not be a controlled study. But I think we're all just curious. We'll frame this as what you do. So water, our water, and I worry about the water, I said, I'd water for a long time in my past life. So we actually distill our water. So we have a tabletop distiller. My husband, Steven, cleans it out. There's a lot of gunk in it. By the way, even though it's San Francisco that has clean water at the end of the day, after you've distilled the water, there's a lot of good.

1:35:51You distill the water. So this is not reverse osmosis. No, distilling. Okay. Yeah. So it's steamed distilled and then it condenses in a glass container. And then we put that in glass containers in the fridge. And so and it tastes really good, by the way, really, really. Somebody just was just over and he said, this tastes like melted snow. I thought it was lovely. And you use that for drinking, for coffee, for tea, for cooking too. If you make rice, you're using distilled water. Actually, no, no. But for ice cubes and you know, whenever I can think about it, we can't use too much because it me too busy.

1:36:25He always said that. But he doesn't want today. And that's just the two of us. So water is important. We try to leave our shoes at the door. Well, dust that you bring in contains a lot of the, particularly the PFAS chemicals. And so that's actually, I'm not 100 % good on that, but we try, try to do that. And I'm careful with the products I put on my face. I check them out the way I suggested, you know, environmental working group. And I go to the farmers market. I always buy organic, always buy organic. But I know that's a cost issue for some people and an availability issue for some people. But in San Francisco, you can do that.

1:37:16Some areas where I don't do more of what I should, I think, I'm starting to be aware of chemicals and clothing. We haven't talked about that. But there's a turns out there's a lot of, particularly in, it's a problem for work out where, because you're absorbing so much, you're sweater, you're hot, and you're bringing these chemicals into your body. And that may be one of the interventions that we do get a bunch of athletes to use safe clothing and traditional clothing and see what their body burden is. That's how you know. So airing toward cotton as opposed to synthetic materials. Right. Right.

1:37:57And the dyes are important. So you don't want, you want maybe plant -based dyes. So not my area of expertise. I have a colleague who I work with on this. And I'll go with her advice. But I'm just saying that's another area that I think people will soon be paying attention to. There's also the area that is much more difficult, which is what's in building materials and furniture. But a lot of these PFAS and the flavor tartans are in our furniture and in our building materials. And trying to think about how to build, I was asked about safety and a new village that's being built in California, by the way.

1:38:35And it's really challenging to think about if you were going to do this right and you were going to build a town that was toxic free, how would you do that? I'm thinking about that. I'm thinking about the opener of the Simpsons and doing the exact opposite. Where like in the opener of the Simpsons, there's like a three -eyed fish and there's the chemical plant. And I'm just thinking you just look at the opener of the Simpsons and you do the inverse of everything that's there. The inverse of everything that's there, including alcohol intake, which is robust on the Simpsons. But interesting. So when it comes to food sourcing, like a non -fruit non -vegetable food sourcing, is there anything we can do?

1:39:21I mean, it's so hard for people to get eggs from farms. I mean, you can if you go to a farmer's market, but this stuff can get pretty tricky, pretty expensive. And most people listening are not going to be living in Sonoma where they might have a neighbor that has chickens or something. Yeah. It's a hard problem. It is a hard problem. And I think maybe people asking for it more would help. I don't know. I mean, in San Francisco, I'm lucky because I can just get just on the phone, fresh direct order. And I know it's okay. But I know that's not the case everywhere. So I think being aware, honestly, is a really big step.

1:40:06If you are aware that this is something you want to change, you will find ways to change it. It's interesting because a few years back, there was a lot of discussion about dyes in children's toys, in particular toys from overseas. Right. Remember kids are not young. Babies are always gnawing on stuff in T the end. And there was a lot of attention like, hey, like what's in these sippy cups? And my understanding is toys and sippy cups. And my understanding is that BPAs were banned from sippy cups. Thalate. Excuse me. Based on your work. Thank you so much. Thank you for the clarification, truly. And for the work that led to that.

1:40:44We have this innate thankfully innate reflex to protect our young, as does every most every species. Thank goodness. And we know that baby skin is more absorbent than older skin. We know. And so there are literally laws in place and restrictions in place to make sure that some this stuff is minimized in young kids. But then we sort of after age 12, we're kind of like, okay, well, it's a free for all. It depends on your budget where you go. And so we can't rely on governing bodies to do this. But I think it's a useful conversation, especially given your relationship to Scandinavia, which is a fun one to elaborate on, to illustrate some of the discrepancy between the US and Europe.

1:41:32What sorts of chemicals are banned in Europe, in food, in lotions, et cetera, that you're aware of that are prominent here in the US. Maybe that's a good filter to place some of this choice making through. Europe has had a policy called REACH. And under REACH, you have to show that a chemical is safe before it's put into the marketplace. Not. I mean, so what the way our system is here is put in the marketplace. And then if somebody gets worried about it, they might do a study. They might find harm. Remember how long it took me to find that salad connection. It was 10 years, two studies, 10 years, 10 million dollars, by the way.

1:42:20So if you're going to wait for that, I don't know, what, you know, given the number of chemicals out there, 80 ,000 or more, forget it. You know, so I think the REACH policy of testing before something's put in the market is making a big difference in Europe. And that's, I think that's one reason why they're much better off. Are those animal tests or animal and human tests that they're doing over there? Whatever defined safety, it depends on the chemical, it depends on, you know, what the product is. I can't answer that in general. So that might be a good avenue for changing legislature here, right?

1:42:56To install something similar to REACH. Absolutely, but it's not going to happen and I don't think. No, no, because there's too many forces against that. It's very, very hard for manufacturers to make changes. I give you one example. So you know that you might not know, but should know that salads are very prevalent in the hospital setting. If you think of a tube, you know, two dialysis, two chemotherapy, two IV, it's all plus, that's all salads, right? And that's going into your body. And there was recently a bill passed in California that DHP could not be an IV bags. It's fantastic. Success. In the actual bag?

1:43:42Yes. The bags could not contain these endogenous structures. DHP specifically. DIAHL hexal thalate, the most anti -endrogenic thalate. So that was a great step forward, but that's like one chemical, right? In one product, and that was a battle. So you see how hard it is to do this. Extremely hard. There's a company B -Bron, which makes hospital products, and they are very forward thinking, and they set up a factory in Florida to make alternative IV bags out of another product, polyolifen. And the problem is that we're not sure about the safety of polyolifen. So it gets really difficult, you know, you can say remove DHP, but now we scientists have to say, what does it mean for a chemical to be safe?

1:44:39And we don't know that. I don't mean to dissolution you and your listeners. No, that's okay. I mean, that's a huge challenge that we're up against. We know it's safer. We know it's safer, and we know what the bad actors are, and we know the things we don't want to be exposed to. But we have to be careful when we think about what do we want to put in instead. Yeah, I'm thinking about this at a former president of Stanford, who was also happened to be a family friend years ago. He since passed Don Kennedy when he retired as president. Stanford went and my understanding is that he went and directed the FDA.

1:45:20And I was just thinking myself like, when did this happen? Because I know he was super into health. He was like an avid runner. He was very fit well into his 70s. Yeah, hip replacement kept running or maybe it was knee replacement. I don't know. The guy was obsessed with health. And so I don't think that there's a lack of interest in health at the level of, it was like the FDA. But there's clearly a problem. And I'm just trying to think of solutions. And it seems to all boil down to what we can take control of in our home. Like when we go to a restaurant, it's challenging to know what they're doing in the kitchen.

1:46:00And at some point it becomes neurotic to, although I know people that won't go to restaurants where they use seed oils. There's this whole new thing cropping up about avoiding seed oils. But maybe there are more significant issues. Who knows? The seed oil crowd is pretty intense. And I like all of oil anyway. So I air to that. But I think if people are interested in limiting their exposure to these endocrine disruptors, one of the key questions that's going to come up again and again, especially in light of PCOS and sperm counts is we can't control what happened to us during pregnancy. But once we have some sense of agency over what we put into our body and how we put it into our body, do you think that there's a plasticity and resilience to this system?

1:46:49So you know, God forbid if somebody was exposed to a lot of these things early on, can they, you know, by making changes, can they, can they rescue themselves to any degree? No. So it's really just dependent on what your parents did. Yes. And that's not to say that your own exposure cannot change things further and make things worse. But here's a fact. If a male's mother smokes when he's in the womb, then he has a, this is a Danish study by the way, 50 % reduction in sperm count. If his mother smoked while he was in the room, how much smoking are we talking? I don't know. Okay. But the, the, the, the reason I bring this up is because there's nothing he can do to change that.

1:47:33Okay. If he smokes as an adult, he has, I think, a similar reduction in this sperm count. He can stop and his sperm will be restored. He can get his sperm health back. But whatever happened in the womb stays in the womb, if you also, it's developmental. It's not going to, you know, it's going to be a full life. And that's true for the brain as well. So I think anybody who's thinking of conceiving a pregnancy or pregnant has a responsibility to really learn how to reduce their exposure because these things are, by the way, passed on for several generations. It's your child and your child's child because the germ cells for your grandchild are going to be carried in, within your child.

1:48:22So germ cells are not germs as an infectious germs. It's the cells that will produce the egg in spirit that germinate. Yeah. Right. Hence the word germ. So it's a huge responsibility. And I think people should take it very seriously. That they have, you know, they're going to be affecting the health of subsequent generation. Some labs say it's seven generations. I don't know if that's true. But certainly three generations are affected. And so I should mention my book. Can I? Yeah, please, I'll mention it. Yeah, I believe I mentioned it in my introduction. Yeah, yeah, please. So in, in countdown, two words, by the way, because if you say countdown one word, you won't find it, but countdown, we have two chapters on things you can do.

1:49:09You need very practical things you can do. And also websites you can go to and links you can go to. Now this came out in a while ago. So 21. So there are many more things now. But I think it's a good start. How lonely are you in this expedition of identifying endocrine disruptors in food, in pesticides, in, in the sorts of things you're talking about? Like, is there a whole field of this of excellent people? Are you, or you a small team of, of people that are against the grain? I, I mean, I confess, I don't know many people doing the sorts of work that you're doing, but I, you know, you're the, the most public facing and prominent.

1:49:51And I, I guess my question is like, is the NIH funding a lot of this sort of thing? Absolutely. It's that we're an army and it's not in this international. And there is now a global plastics treaty under negotiation, by the way. Tell us about the plastics treaty. People are trying to create, get past by various countries, um, an international plastics treaty. I can't, I don't want to talk a lot about it. I'm not involved in that process, but I, in the process you, you, you could see, if you looked into their hundreds of scientists and concerned citizens and activists and, you know, people in legislation who are working to specifically on the chemicals in plastic.

1:50:42Now, plastic is really a bad actor. I, I, but it is not the only bad actor. So I want to just mention that plastic is really important, but, you know, pesticides are not plastic and, and so on. So there are many other classes that you have to worry about, but certainly controlling our exposure to plastic is huge. And, um, the, you asked about scientists in this area. Yes, there's a huge amount of science going on for this in this, there's, um, and it's funded by NIH and it's funded by, um, the EU and, um, primarily, I think those are the two, two funders of Scandinavia has funding within, you know, in Scandinavian countries.

1:51:26So there's a lot of work and a lot of very good people working really hard, but it's a huge problem and it's been here since, well, plastic started to rise in popularity in 1950. So we have like 75 years to battle against and it's not going down any time soon. Lifespan is increasing pretty significantly, presumably in large part because of the reduction in smoking and control of infectious disease. In control of infectious diseases. But lifespan is definitely increasing. Whereas the use of plastics has clearly increased, and so I guess one could argue that we're living longer, but we are less robust than we were, less, um, reproductively competent.

1:52:18Is that the people that are reflected in that long, or lifespan were not necessarily exposed early in life, which is when it's most critical. So, you know, I was born in 1936. There was no plastic. There was no, you know, um, and there were other things, of course, but not as they are today. So, um, I don't think that you can make the inference that because we're living longer plastic growth, you know, the growth of the plastic centratres, somehow driving that longevity, absolutely not, absolutely not. I think what it's driving is decrease in fertility. And what's happening is that the shift in populations is pretty dramatic.

1:53:01We're getting, you know, the pyramid used to be like this. I'm making a triangle with my arms, showing very few people on top and a lot of people on the bottom. But what's happening is that that's getting inverted. So, we're getting more and more people on top and fewer and fewer people on the bottom. Birth rates are weighed down. Birth rates are weighed down. And so, this is a enormous problem for societies because the people in that small support group at the bottom can't drive the society to support the large growth on top. You see what I'm saying? This is true in other countries as well. Yes, absolutely, absolutely.

1:53:40It's all over the world. And, and the decline in fertility, in my mind, is probably, well, one of the biggest challenges we're facing now because it's everywhere. It's very acute. And there's only limited things we can do to counter it. There's a wonderful website called, it's by the World Bank, put out by the World Bank. It's called fertility data. And if you go in there, you can see what is the fertility rate every year, but you can put in, you know, plug in a country or a year or, you know, and see what the fertility rate in each country in the world each year. And you can see that. And what you see is that decline, about the same rate as sperm decline, by the way, about 50 % in 50 years.

1:54:33And the critical point for fertility is two. So, what's that mean? That's called replacement. And that's two people replace themselves with a total fertility rate of two. Actually, 2 .1 because you have a little bit of loss. But 2 .1, you're good to go. Society, when you fall below that, you're shrinking. And there are many countries in the world that are below that, including the United States. And for example, the worst I've seen is actually South Korea, which is at 0 .78. Wow. Japan is at 1. So, large parts of the world are just not replacing themselves. And why that is is maybe another discussion, or we can talk about it.

1:55:21I don't know if you want to go into that, but it's not just sperm count, for sure. You know, along those lines, let's talk about egg count and quality. You mentioned the PCOS results earlier. Before we were on Mike, you mentioned an interesting study that you did about the use of electric blankets. And assessing whether or not the use of electric blankets had impacted egg number or quality in women. And the answer was. It actually what we looked at in women, I'm sorry, to correct you, but it was the outcome of their pregnancy, their fertility. And we think I'd pregnant. How did that turn out? Excuse me.

1:55:59So, thank you for that clarification. But I'm sure there be a lot of other studies that have looked at that. I just have been away from that field for a long time. But so far, I don't see convincing evidence that the use of cell phones or other exposures to electromagnetic radiation are affecting our pregnancies and our fertility. That's not to say it's not happening. But I have not looked at it. And I don't like to make statements about things I haven't looked at. My understanding of the cell phone data for sperm count and motility, aka quality, is I discussed a meta -analysis covering this on the podcast previously, is that there are some heat effects of cell phone use in keeping the phone in the pocket that may, I'm going to be careful here, impact sperm count and motility quality.

1:56:55But direct effects of EMFs on sperm, there's no evidence that it is disrupting sperm, at least to my knowledge. I honestly have to say, just going to say I don't know. But I do know that heat is related to fertility in sperm count. And you can look at the birth rates as a function of the month of conception. And you can see that, for example, in warm months, in warm climates, there's less. So there are heat, heat does play a role. But how much that's tied to cell phone use? I think that's something that's now under investigation by a lot of groups. And we'll see what they find. Yeah, the data on sitting more than a few hours a day on having legs that are very large as the consequence of obesity or even just legs that are large, heating the scrotum.

1:57:47And those data are fairly, I would say, solid in terms of the relationship to reducing sperm count. Heat is not good for sperm, which is why the scrotum has its features that it does to move that the test goes further or closer to the body. Game back to egg, egg counting quality. There's some entering puberty earlier, but that women are also undergoing paramedicosamine impositor earlier. Earlier. Do we know what that is the consequence of? There are several new papers actually on the menopausal age showing relation to a number of chemicals, but I can't quote them to you right now. I don't remember which class it was that they looked at, but I think that's right.

1:58:36I think there is growing evidence that earlier fewer. It's also called premature ovarian failure so that women are just not producing the eggs as long as they used to. But I just want to say something about the fertility. Can we go back to fertility? Please. So when this comes up, and I'm sure you've seen the literature, there's a lot of literature on this that say fertility is going down, fewer children are being born. A, people say, well, that's a good thing because it's less of a load on the planet, which is another discussion. And then they say, well, this is due to choice. That people are choosing to have fewer children.

1:59:24And they're choosing to delay childbearing till they're no longer as fertile. They're using more contraception. Women are more educated. They're entering the workforce. All of these social factors are given as the reason for decline in fertility. And I just need to point out whenever I hear this, that it's not just human fertility that's declining. The number of species that are becoming extinct is increasing rapidly. And there has been for at least 40 years evidence that those pesticides that affect us are affecting animals as well. And so the decline in fertility and non -human species cannot be attributed to delayed childbearing or use of contraception.

2:00:21Or rent prices. And it's interesting because we usually hear first about species that are about to go extinct, that are badly endangered. I don't know what the proper language is, but it's about to go distinct. Like the Florida panther. Or we hear that these species of there's a very small subset of them left. The black -footed ferrets in Montana. I think one ferret, his name is Scarface, sired something like 300 litters that then led to the eventually they started out out reading. Because if you do too much in reading, obviously it's not good. But then they were able to at least partially recover, maybe fully recover those populations.

2:01:01And people forget the domino effect of these ecosystems when one species is compromised. Like when the black -footed ferrets I know about sound kind of silly, but were compromised in terms of their populations. The prairie dog population went up. The grasses were getting eaten far more. And then there's all these downstream consequences on bugs. And I'm not an expert in this, but one doesn't have to be an expert to understand. Like you move one pin here and the whole web moves. And so or you move one node and the whole web reconfigures. And that's what nature has been doing for millions of years.

2:01:41But at some point it is conceivable, no pun intended, that we are going to be the species on the endangered species list. That's not like an outrageous sci -fi movie. At some point humans might be added to the endangered species list. With the exception that we have, we're very clever. And so we found a lot of ways to do medically assisted conception. Right, Ixsey, the literally gentle grabbing of one sperm and forcing it to fertilize the egg is something we've covered on this podcast in our fertility episode with Natalie Crawford and a solo episode that I did. There are questions that people have, reasonable questions about whether or not the offspring of those types of scenarios are the same as the genetic probability experiment.

2:02:37As you mentioned before, of having 200 million sperm and then letting nature select the one that is most robust in that environment. Yeah. And the number of technologies is increasing. We're very clever species. And for example, I don't know if you've heard of gameter genesis. So it is now possible to create an embryo from a sperm cell. From a skin cell, a skin cell can produce a sperm cell and an egg cell. So you give it the right transcription factors and you can... So this is kind of interesting, exciting and scary. That's a wild story. This is like the, what is it? I think the vultures, the females, there's some way in which two female vultures or maybe a single female vulture can create offspring in the absence of a male.

2:03:32There's also a three -party IVF. I don't know if you're aware of this. This was developed where there's a mitochondrial disease. You can take the two eggs, one from the intended mother. You take the nucleus, so you get the DNA, you put it into an egg of somebody that where the DNA has been removed, but where the spindles, which are rich with mitochondria, are from a typically a much younger post and then you use a sperm. So it's actually three parents is the spindle of one mom, the DNA of another mom and a sperm. They do this in the UK for mitochondrial disease. It's still illegal in the United States as far as I understand.

2:04:08And it's done in other countries. And in theory... Legal issues must be. Yeah, but in theory, this would allow women of any age provided they can still have eggs to have their DNA propagated forward because the DNA can be put into a younger egg that has the spindle quality that allows for the production of more cells. This can and has been done in humans. Yeah. So we're... I mean, you and I won't think of all the things that will be developed, you know, in the next 10, 20 years to, you know, to meet the challenge of declining fertility by ordinary conception. I mean, I think that's how we're going to solve this problem for us.

2:04:57We're going to just be smarter and smarter about how to do a medically assisted conception. And then the question is going to be... And it'll take time to know this is whether there are effects in the offspring, adverse effects in the offspring. It's a little tricky because, for example, if you use the sperm of an infertile couple and you see, let's say, the sun is subfertil. That's born that way. But you do it in a test tube or whatever. And then you can say, well, maybe that's because the father was infertile and he's got inheritance from the father from that, you know what I'm saying? So you can't know whether the...

2:05:44If you see an adverse effect in or if an internoffspring, you have to be very careful that it's not something that they've gotten because of problems that led the couple to seek assisted reproduction. You see, you following me? Yep. Super challenging, fascinating problem. So in anticipation of this sit down together, I put a question out on X, formerly known as Twitter. I let people know that I was hosting an expert in endocrine disruptors, in taliates and pesticides, reproductive implications, etc. And I asked for questions and they came up with a huge number of excellent questions, many of which you've already answered.

2:06:32Things like, is cap water safe? What can we do to our tap water? You mentioned you distilled water. My understanding is that reverse osmosis provided there's remineral remineralization, excuse me, difficult word to say, can also be effective, etc. There were a lot of questions about cosmetics and laundry detergents. I don't know if we discuss laundry detergents. What do you use in terms of laundry detergent? Or that is presumably one can find... I don't even remember. Okay. Don't go by my products. Okay. For one thing, I'm not going to be pregnant anytime soon. No. I believe there are some solutions related to that, like instead of bleach, people can use hydrogen peroxide.

2:07:21I can't speak about specific products, actually. You know, I can tell you who can, may you might like to talk to her. So, remember I mentioned million marker, the company that did the inventory, not the company, well, they are a company. But so they look at million marker. I think you'd be interested. Okay. Yeah. And the person who runs at Genoa is a Chinese American who and a friend of mine and we're going to be writing a grant together. And she participated in the film. So our participants sent her... So, if you go to million marker, you log on and if you agree to pay whatever it is, $199, I think you send your urine in, that give you a kit, you say, you're urine and they test it for all these things in your urine.

2:08:07So you know what's in your body. You might want to think about it. It might be interesting. And then if you pay another hundred, I think you get these, this counseling and so on, blah, blah. You see, you can see the different levels. But she knows all about products. I don't know about products because it's a moving target. I don't and also I don't like to talk about product names because it sounds like I'm endorsing them. Yeah. Right. And we won't expect you to give product names and I'll follow your recommendation that you just gave. Somebody asked about food dies, just generally the dies in foods.

2:08:40I saw an incredible study recently that Science Magazine covered. So Science Magazine, very reputable. Of course, yellow number five. I forget what the precise name is, but the thing that makes Cheetos really bright, they put it on the bellies of adult mice, and it literally makes them translucent. Oh, yeah. So you can see the organs. It's wild. It's so scary. I sent it to Rogan and he, I won't, he was like, whoa, his, his version of whoa. I was like, I also said, whoa, he probably said holy shit, right? No, I'm not going to say what it said, but it was, he didn't curse. There were a number of questions about household items.

2:09:21Again, we're not looking for specific products, but for instance, soaps, body wash, cleaning sprays, floor cleaners, laundry related cleaners, do any or all of these contain endocrine disruptors, unless one is careful to find the ones that count. Okay. Receipts, how serious is it? Should we be concerned about the BPAs and other endocrine disruptors on receipts? Yes. And my suggestion is just ask for an electronic receipt, and then you don't have to jail. But they're definitely absorbed into your body. Any impact of endocrine disruptors of the sort we've talked about today on the thyroid system?

2:10:04Yes. Presumably in the in the bad direction. Yeah. I mean, this is an interesting point. Let me just say another word about it. So the there was an ongoing study in the Faroe Islands off Denmark. And they studied PFAS chemicals and showed that people who fish there, there were fish for people and they they ate the fish and they were getting high levels of PFAS in their body and had, and this is published effects on their immune response. So my concern, and I don't know if anyone's looked at this, is given everyone's vaccination, you know, our is our response to vaccination now altered by these chemicals.

2:10:54I don't know, but I think it's a really interesting question. But there is a whole field of the effect of these chemicals on the thyroid system. And there's a lot of evidence that it's adverse. Can these endocrine disruptors be detoxed from the body? Is there anything that we can do? What's the quickest ways? Things like sweating. Are there ways to improve liver clearance of these endocrine disruptors? That the answer that depends on the class of chemicals. So the chemicals that are water soluble in particular, the phallids and the bisfinols, leaves the body in a matter of hours. You don't have to do anything.

2:11:30You just have to stop taking them in. Right? The forever chemicals, the PFAS chemicals, pesticides are, and though, but so what has to do with how they're handled by the body? Are they put into the, you know, if they're water soluble, you pee them out. If they're fat soluble, they're going to be around for a long time. So it just depends on the chemical structure of the chemical of the compound. There was a question about non -stick pans. You covered that earlier. If someone had to pick between non -stick coated pans versus seasoned iron pans. No question iron. There's no risk associated with seasoned iron pans.

2:12:12A number of other questions such as why does Europe have such more stringent laws, et cetera? Lots of questions about atrazine, questions about ointments and fragrances you've covered. I must say that as I scroll through these hundreds of questions, if not more, you've done an amazing job at clarifying for us what's known, what is not known, and essentially where it's a probably should avoid, definitely avoid, and look, we just don't know. Well, you know, there's a hefty distinguish between we don't just don't know and I just don't know. It's not, I mean, there are many things that I don't know.

2:12:58It's a huge feel. So, you know, maybe with some, you know, ask the question of chat GPT. Yeah, we'll be certain to ask chat GPT and we will be certain to ask other experts in these areas, but I just want to make very clear eye and everyone listening and watching truly appreciate the work that you've been doing in this area for a number of years. We're so grateful that you took that airline flight with your this chemist that you mentioned that you stored the urine of those pregnant women that you analyzed it and that you've gone down this path of exploring, you know, things that are really disruptive to our health and potentially to the existence of our species.

2:13:48As, you know, as we talked about earlier, there is the possibility that we go extinct, not because of a meteor, but because we fail to replace ourselves and that we fail to replace ourselves because we destroy our biological ability to replace ourselves. I think it's hard for people to internalize that very real possibility because we feel ourselves sitting in traffic with thousands of other people and there's a lot of too many people, right? This kind of thing, but I want to thank you for the work that you've been doing and continue to do for your willingness to write books and to educate the public on podcasts like this and others because these are topics that are pretty emotionally loaded for people.

2:14:31I don't think anything gets people quite as inflamed as the idea that what they've been ingesting and exposed to, especially in terms of consumables that they've spent their harder and money on have been harming them and they're offspring and generations to follow that there's something that really lands deep in that way, but you've also offered us a lot of possibility and a sense of agency over these things and I love that you weave your math and statistics and probability theory background into all of this because what comes through intense curiosity, intense rigor and a real desire to do good.

2:15:11So thank you so much for joining us and please come back again as you make more discoveries. It's been really fun. Thank you for joining me for today's discussion with Dr. Shauna Swann. To learn more about her work and to find a link to her excellent books on these topics, please see the links in the show note captions. Also, I should mention that if you're interested in learning more about microplastics and endocrine disruptors, I did a solo episode, the Hubertman Lab podcast on that topic and that is also linked in the show note captions. If you're learning from Ender and join this podcast, please subscribe to our YouTube channel.

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