The Art of Manliness - July 19, 2021


The Strange Science of Sweat


Episode Stats

Length

48 minutes

Words per Minute

173.25378

Word Count

8,402

Sentence Count

7

Misogynist Sentences

23

Hate Speech Sentences

12


Summary

In this episode, I speak with science journalist and author Sarah Evarts about the surprising quickness with which the things we drink start coming out of our pores, why we sweat when we're anxious or nervous, and why it feels so good to make ourselves intentionally sweaty through things like a sauna.


Transcript

00:00:00.000 start jogging around the block or simply sit outside on a hot summer day and you begin to
00:00:10.900 feel moisture develop all over your body maybe you drop a sweat roll down your face clothes
00:00:15.040 start to get sticky you start feeling in greater intensity a process that's actually going on all
00:00:19.560 the time sweating you may never thought too much about your sweat or perhaps been a little
00:00:23.540 embarrassed by it when your sweat becomes noticeable in a socially delicate situation
00:00:27.060 but my guest today says that human sweat is in fact incredibly fascinating and something you
00:00:31.040 should embrace with real appreciation and enthusiasm her name is sarah evarts and she's a science
00:00:34.960 journalist and the author of the joy of sweat strange science of perspiration sarah and i begin
00:00:39.320 our conversation with what sweat is the two kinds your body produces and how human sweating is unique
00:00:44.020 in what sarah calls our species superpower we then get into the surprising quickness with which the
00:00:48.560 things we drink start coming out of our pores why we sweat when we're anxious or nervous whether how
00:00:52.900 much you personally sweat comes down to genetics or environment and why the fitter you are the
00:00:56.980 more you sweat sarah impacts whether there are differences between how men and women sweat and
00:01:00.740 smell whether our dislike for body odor is innate or culturally conditioned why some people are
00:01:05.200 smellier than others and the role that smell and pheromones play an attraction sarah also explains
00:01:09.560 whether antiperspirants are bad for you and if you should switch to a natural deodorant and we
00:01:13.120 end our conversation with why it feels so good to make ourselves intentionally sweaty through things
00:01:17.060 like a sauna and whether hitting the sauna can detox your body after the show's over check out our
00:01:21.120 show notes at aom.is sweat all right sarah everts welcome to the show it's great to be here so you've
00:01:34.080 got a book called the joy of sweat the strange science of perspiration and this book had you traveling
00:01:39.300 around the world talking to scientists about sweat so how did that happen how did you end up traveling
00:01:46.820 the world you went to germany i think you went to different countries i think russia at one point
00:01:52.540 to research about sweat how'd that happen well you know i'm a science journalist and you know a long
00:01:59.280 time ago i was a chemist but i'm also a person who was like always slightly afraid that i might sweat a
00:02:05.940 little bit too much and you know at some point i kind of decided you know let's just uh like dig into the
00:02:13.540 research on sweat instead of like being anxious about it and so yeah i tracked down people who were
00:02:20.240 doing scientific analyses of sweat and then also people who are kind of playing around with cultural
00:02:25.380 taboos and yeah for example that's how i ended up in moscow at a sweat dating event and so something you
00:02:32.720 highlight in the book is that sweat is something we all do but sweat has pretty much gotten the short
00:02:37.660 shrift in scientific research what's going on there why is that yeah it's really interesting because
00:02:42.780 like if you just like look at the scientific literature you see that compared to say pee um
00:02:49.680 sweat has like an order of magnitude less articles about it and you know you wonder if if scientists
00:02:55.380 just wondered if it was just salt and water and actually sweat is so much more interesting than that
00:03:03.300 because it's sourced from the watery parts of blood pretty much anything that's circulating around in
00:03:10.640 your blood system kind of emerges out in sweat because your sweat glands you know once the big
00:03:16.820 things in in blood like red blood cells platelets immune cells are filtered out all that liquidy stuff
00:03:22.120 gets dispatched to your skin when you're too hot all right okay so that's interesting we'll talk more
00:03:26.860 about what makes up sweat but that's something i learned like what is sweat well it's salt and water
00:03:31.940 because we've all tasted our sweat probably but i didn't know it came i didn't know it came from your
00:03:35.940 blood like it's just basically your blood yeah it's it's the the liquidy parts so effectively
00:03:42.560 you have that's called blood plasma and you know when you cut open a body you know i don't mean that
00:03:48.800 in like a horrific way like our bodies are wet inside right there's there's moist liquid around all of
00:03:55.040 our organs that's called interstitial fluid and so interstitial fluid comes from blood plasma that
00:04:00.700 liquidy parts of blood and then when we overheat and our sweat glands get the like big directive to
00:04:08.200 open the floodgates well what do they do they go to that interstitial fluid and they dispatch it to
00:04:14.560 the surface because when you evaporate water this kind of consumes heat and so the sweat evaporation
00:04:22.940 effectively whisks heat away from your hot body and out into the atmosphere you also mentioned the book
00:04:29.720 okay sweat is primarily salt and water but there are two types of perspiration right you have two
00:04:34.360 types of sweat pores what are those two types of sweat pores and what's the difference between the
00:04:38.000 sweat that comes out of each one out of our sweat pores that cover our body we have about
00:04:44.760 two to five million i have three million sweat pores that is called eccrine sweat and that's that
00:04:51.060 liquidy part of the blood that's responsible for helping us cool off but there is another kind of
00:04:57.080 sweat gland and that's the one that appears in armpits at puberty it's called the apricline gland
00:05:03.240 and its sweat is actually not watery or salty at all it's very waxy it's actually pretty similar
00:05:09.940 to earwax and when that sweat starts coming out anywhere where hair grows at puberty bacteria living in
00:05:18.880 your armpits eat and it's their metabolites effectively bacteria poop that is that stinky smell that starts
00:05:27.000 wafting out of armpits from the teenage years onward we'll talk a little about bo here in a bit but
00:05:33.100 do we know why we have that special armpit gland like why do we sweat that what's the purpose of it
00:05:39.000 right that's stymied scientists for a long time but many think that it does have to do with what's
00:05:45.240 called chemical communication that or odorous communication that this is a way that we share information
00:05:52.600 about ourselves to other humans and it probably had more of a role earlier in our evolutionary history
00:05:59.220 but it's kind of like vestigial it's still there around and then of course some people speculate
00:06:04.700 that it's involved in you know sexual maturation that it's somehow involved in you know love or at
00:06:12.880 least romance because it appears at puberty right when everything else gets cracking for procreation
00:06:18.340 all right and that connects to the subject of pheromones and we're going to talk about that
00:06:21.960 here in a little bit but let's talk about the idea of sweating in the animal kingdom in general
00:06:26.460 so all animals have to keep themselves cool somehow because just living creates heat through metabolism
00:06:32.260 and if you don't cool yourself off you're going to die but the way humans cool off with sweat is
00:06:38.220 different from other animals how so right so sweating as much as it's kind of gross to a lot of people
00:06:44.460 it's actually our superpower in the animal kingdom it's one of the things that makes us unique along
00:06:51.160 with nakedness and the reason it's such a superpower is that it allows us to cool down while we're on the
00:07:00.120 move so if you can imagine in our history you know many of the prey that we needed to hunt sprints
00:07:07.200 faster than us but because we have this huge surface area for evaporating off water getting rid of
00:07:14.340 our body heat we can cool down while on the run and so our prey you know sprints away super fast
00:07:19.960 but then they have to stop and cool down because death by heat stroke a terrible way to die and you
00:07:26.820 know eventually we can catch up forcing them to sprint away and sprint away and sprint away until
00:07:30.920 they're so weakened by heat stroke that you know they're easy to to kill or to hunt and what's so
00:07:37.560 amazing about humans is our naked skin surface right so if you think about a dog panting we all know
00:07:45.380 that's how dogs cool down it is evaporating away water because that's the best way to cool your body
00:07:52.180 down but it's doing it off the only naked surface that it has its tongue right and instead humans have
00:07:59.360 our whole bodies to do that on and even chimpanzees are our closest evolutionary neighbor or relative
00:08:06.340 although they have sweat glands over their whole bodies many many primates do not all but some
00:08:11.700 they are cooling down by panting because you know our naked bodies have that surface area and you know
00:08:19.380 the modern incarnation of this is you know we can run marathons we're really good at you know not
00:08:25.500 dying of heat stroke while we're exercising heavily yeah we uh had daniel lieberman on the podcast and i
00:08:33.260 think you talked oh he's great yeah and he talked about there's they've done he's done a race with
00:08:37.680 horses like so it's like a long distance race where he raced a horse and in the beginning the horse was
00:08:42.720 beating him but eventually the humans all beat the horses because the humans can keep going because the
00:08:47.320 horse at the stop because they overheat and they have to cool down exactly and what's kind of also amazing
00:08:53.440 is that because this like evaporation of water is so important for staying cool animals dispatch other
00:09:02.940 bodily fluids whatever they have available to the surface of their their bodies to get rid of heat
00:09:08.640 and you know you know dogs use saliva but you know seals rely on urine honeybees vomit on themselves
00:09:16.580 all to get their bodies wet so that it can away heat and the thing about humans is a we've got
00:09:24.520 specialized glands just to do this number one and number two we do it so much more efficiently than
00:09:31.280 than all other animals and so yeah it really is our kind of amazing evolutionary superpower and if you
00:09:37.280 know what evolution could have bequeathed us like we could be cooling down from pee like would you know
00:09:44.300 that sweat is so much less gross right yeah i'm grateful i don't have to pee myself to cool myself
00:09:49.820 down so let's talk a little bit more about sweat so one of some of the research that's been going on
00:09:55.680 is trying to figure out how soon does the water we consume become sweat and i think that also we
00:10:03.400 need to ask too is like how often are we sweating are we sweating all the time or do we only sweat when
00:10:07.560 we get you know reached a certain temperature right we are sweating all the time if we weren't
00:10:13.220 we would be freaking miserable right our body's constantly making micro adjustments and most of
00:10:20.720 the time when we notice sweat it's because we've you know upped our activity and so our sweat glands are
00:10:26.780 like on hyperdrive and they're like crap we got to get going right but at any moment your body is
00:10:32.960 releasing a tiny amount of sweat to make micro adjustments to your internal temperature and so
00:10:39.120 you know as as a result we do need to drink water to stay hydrated and uh there's this awesome
00:10:45.980 scientist that you're kind of referring to this guy named michael zek who really likes going to the
00:10:50.900 sauna and uh one time he was like in the sauna getting philosophical with his buddy and they were like
00:10:57.580 hmm you know i wonder how quickly you know when you drink a glass of water how quickly does that water
00:11:05.020 you know get absorbed by your intestinal tract get you know put into your blood get dispatched to your
00:11:12.300 you know internal organs percolate to your skin and then emerge out in sweat and you know when most of us
00:11:18.660 get philosophical in the sauna you know that's the end of that but because he's a scientist he could do the
00:11:24.380 experiment and so he spiked his favorite rehydration drink which in germany for him is this weird
00:11:32.820 combination 50 50 cola 50 50 wheat beer it's kind of like a brown shandy and uh so he spiked it with
00:11:42.040 this chemical that he could measure and that's not normally found in our bodies or in our sweat
00:11:48.380 so he drinks his cola weizen it's what it's called and then quickly undresses gets into the sauna and starts
00:11:56.140 measuring and capturing the sweat coming out of his skin at timed intervals and he found that
00:12:02.260 it took 15 minutes for that chemical tracer that he had put in his drink to come out of his sweat
00:12:08.860 pores which is pretty fast right that is really fast i didn't think it would be that fast
00:12:13.280 no neither did i he he made me guess um and i i guess closer to an hour but uh yeah nope it's really
00:12:20.460 fast so sweats primarily to regulate our body temperature but we also sweat when we're anxious
00:12:26.840 nervous why do we do that that's super interesting to me so there's like a lot of speculation about
00:12:34.980 this one idea that uh researchers have is that it's kind of anticipatory right when we're anxious
00:12:42.900 for most of human history we've had to like run really fast away from the thing that we're scared of
00:12:48.700 and so it might be our body effectively predicting from anxiety that we're going to be running and thus
00:12:55.940 turning up the heat and that it would be wise to perhaps start the cool down strategy pronto but
00:13:03.500 it's also this really interesting kind of vestigial aspect of evolution so remember how i said humans
00:13:10.460 have these salty sweat glands over our whole body we've got millions of them and what's really
00:13:16.820 interesting is that all mammals have those salty sweat glands but they're only located for most mammals
00:13:24.160 in their paws and that was because initially this eccrine sweat this kind of salty you know watery
00:13:31.580 parts of blood was used for grip for climbing and effectively when an animal got scared and had to like
00:13:38.060 run away possibly up a tree that's a little bit of that sweat would come out to help them with grip
00:13:43.560 and so you know when you're stressed out and notice that your hands are getting sweaty it's a vestigial
00:13:50.660 response um from you know your your mammalian predecessors that had to climb a tree in their anxious moments
00:13:59.040 interesting so another thing you highlight too is sweat works better in certain climates than others and
00:14:05.300 keeping it cool so the whole cooling mechanism is evaporation how does climate affect how effective
00:14:12.660 that evaporation cooling is yeah so you know in a hot climate you can imagine the sweat is evaporated
00:14:23.140 much more quickly away and that's due to some chemistry that you may have learned in high school
00:14:28.880 like in a very humid place there's already a lot of evaporated water in the atmosphere and it's kind of
00:14:38.520 giving a pushback to the water on your skin that's trying to evaporate to whisk away heat and so in a
00:14:45.920 desert the water that you emit with sweat really evaporates quickly and so that's really good for
00:14:53.480 cooling it's not good for for hydration that's why in many very dry climates you're advised to wear
00:15:00.700 cool loose clothing so that you kind of keep a little bit of humidity at your skin surface right
00:15:06.760 but in really super sweaty climates or humid climates sorry you want to take off as much clothing as
00:15:13.760 possible to effectively give all those water molecules on your your skin a chance to to get
00:15:20.120 out and away even when there's already a lot of water molecules around in the atmosphere kind of taking
00:15:26.500 up space all right that's a good practical takeaway there keep me cool i live in oklahoma it's really
00:15:31.020 humid here so wearing lots of loose clothing during the summer not probably a good idea
00:15:36.560 but if i were in arizona yes yeah exactly and if you think about what a dog does while they're
00:15:44.260 panting the whole reason that they're heaving in and out like the panting part right is they are
00:15:50.300 trying to push all that water that is just evaporated up off their tongue and is making the surface just
00:15:58.280 above their tongue dense with water molecules they're heaving all that wet air away and allowing
00:16:05.300 drier air to come on top of their tongue to make more room for more water molecules so that's the
00:16:11.380 whole point of panting is to kind of move that wet air away as fast as possible especially since
00:16:17.040 they don't have a lot of surface area for this cooling strategy well let's talk about how sweating
00:16:22.060 differs across populations so you you started this book because you thought well i'd probably sweat more
00:16:26.680 than most people and you just told me you have three million sweat pores how what influences how much
00:16:31.800 we sweat is it primarily genetics or can our environment also play a role yeah it's a bit of
00:16:38.400 nature and nurture situation so certainly um some families are sweatier than others and that could be
00:16:46.140 due to you know just the number of sweat pores that you have on your body there's quite a range also
00:16:51.740 like the flux out of your sweat glands so how quickly the sweat is coming out that's a big range and
00:16:59.400 your genetics might mean that you have a bigger flow than i do or i probably have a bigger flow than
00:17:05.980 you and then there's also you know how quickly how responsive your body is to temperature changes
00:17:12.160 but what's really interesting is this nurture side and evolutionary biologists are are really digging
00:17:19.060 into this right now because when you're born you're born with all the sweat glands that you're
00:17:25.020 gonna have like sweat glands are developed in utero but they don't all become active at birth it's only
00:17:33.100 in your toddler years that like they come you know to become fully operational so to speak and so in
00:17:39.540 those first early years of your life your body is cluing into the environment in which you live and
00:17:45.340 and learning whether you know you're in a super hot place and so you have to maybe be a bit more
00:17:51.480 active or more efficient or whether you're in a cool place and so yeah there's this mix of both you
00:17:57.260 know what you have genetically and you know where you spent your early years i mean the take-home message
00:18:03.380 though is that you can blame your parents for both because uh they're responsible for your genetics and
00:18:09.060 you know also presumably where you spent your toddler years well let's say someone is born in a
00:18:14.680 cool cold dry area and then they move to florida for example will their body adapt and sweat more or less
00:18:24.540 based on that that move right so there your body's uh acclimatized right so you know but they do it a
00:18:33.700 little bit slowly and then you have this like baseline which you start with so you know for example
00:18:39.740 right now athletes are prepping for tokyo where it's super humid and super hot some say it might
00:18:45.880 be the hottest olympics ever and so they are all training in extremely hot weather so that their
00:18:52.800 bodies can figure out how to be efficient at cooling in extremely humid hot weather so you do there is this
00:19:00.560 process where your body does learn to adapt but at some point we all have a baseline and that baseline is set
00:19:08.240 in your your toddler years and so yeah you know there are some micro adjustments but um at some
00:19:14.360 point you're stuck with what you have we're gonna take a quick break for your words from our sponsors
00:19:18.540 and now back to the show something i've read i don't know where i read it maybe on the interwebs or
00:19:27.000 on like in a men's health magazine from 1992 or something uh is that the fitter you are the more
00:19:32.540 you sweat is there anything to that well yeah because if you are super fit right your body has
00:19:40.140 learned that when you start exercising when you start dialing up the temperature you are not going
00:19:45.760 to be doing this for you know 30 seconds or even you know 15 minutes you're probably going to be doing
00:19:51.440 this for like over an hour and so athletes actually have a tendency to sweat more the more that they train
00:19:59.840 and the and the fitter that they are and this is also true for people who kind of have sauna going
00:20:05.280 as as a hobby so for example i noticed that when i moved to germany and you know wanted to you know
00:20:12.660 integrate with the locals who are all obsessed with going to to the sauna that my sweating rates got
00:20:18.860 faster and more voluminous because i was suddenly going to the sauna not just for you know a one-time deal
00:20:26.240 but like going regularly and spending a heck of a lot of time in a really hot space so ultimately
00:20:31.500 it's all part of this like acclimatization process where your body is like learning about your behavior
00:20:37.760 and figures out that oh geez when the temperature rises she's going to be in there or he's going to
00:20:44.960 be in there for a heck of a long time let's get cracking on the cool down directive are there
00:20:50.140 differences between men and women and how they sweat not really so generally uh any differences
00:20:57.140 that you see are most likely just due to volume to surface area issues there's not anything really
00:21:05.300 biologically different in how sweat glands work or or how many there are but because you know men are
00:21:11.980 on average larger than women they've got slightly more sweaty activity because they've got that much more
00:21:19.580 body to keep cool well let's get to the fun stuff here which is like why sweat smells and like the social
00:21:27.200 aspect of being smelly humans so you mentioned earlier that one type of sweat forgot the name of the gland
00:21:33.600 the sweat pore that produces starts with an a right oh apocrine yeah the apocrine sweat that's the stuff
00:21:40.440 so the bacteria on our skin and our armpits starts eating that stuff and the bacteria fart and that's
00:21:47.360 basically our bo why do i guess i would say i think americans or westerners in general like why do we
00:21:54.700 find bo so off-putting like why don't we like it well so i would say two things i think that americans
00:22:02.040 take it to a whole nother level of of insecurity but i would say that for much of human history people
00:22:09.420 have been kind of worried about the odor of themselves so one of my favorite quotes which is on my wall right
00:22:17.100 now it's advice from the roman poet catullus so literally like two thousand years ago um to his
00:22:22.980 friend and then his nemesis this guy named rufus he says um wonder not rufus why none of the opposite
00:22:29.700 sex wishes to place her dainty thighs beneath you not even if you undermine her virtue with gifts of
00:22:36.120 choice silk or the enticement of a pellucid gem you're being hurt by an ugly rumor which asserts that
00:22:42.520 beneath your armpits dwells a ferocious goat this they fear and no wonder for it's a right-ranked
00:22:48.360 beast that no pretty girl will go to bed with so either get rid of this painful affront to the
00:22:53.020 nostrils or cease to wonder why the ladies flee so i love that because you know it speaks to the fact
00:22:59.600 that you know for at least two thousand years we've been a bit worried about our body odor but most of
00:23:06.940 that time the way that we've dealt with it is to wash with water possibly soap and or apply a huge
00:23:14.740 amount of perfume to kind of overwhelm our bo and it wasn't really until the turn of the 20th century
00:23:22.300 when what we you know use now deodorant and antiperspirants get invented and so up until this
00:23:28.840 point people have a background body odor of of each other they know each other's body odor really
00:23:35.400 really well and you know it kind of reminds me of the difference between smoking laws right back in
00:23:42.460 the day you know you'd go to a bar and there would be tons of smoke and you'd go home and you wouldn't
00:23:47.900 notice it and now because we have made this very you know smoke-free environment when you do go to a
00:23:54.460 very smoky place it's all the more like you notice it so much more it feels so much more intense so over
00:24:02.520 the 20th century we dialed down you know our body odor uh to the those around us a lot more because
00:24:10.620 of these products but you know simultaneously those that marketed these products used this thing
00:24:17.260 invented this thing called whisper copy which puts the fear of stink in humans and you know in the
00:24:23.900 1919s they started their advertising strategies towards women and then they started trying to convince
00:24:30.020 women to buy deodorants and antiperspirants by saying listen you know if if you sweat you stink
00:24:36.520 and people are talking about you behind your back and not only is this gossip hurting your reputation
00:24:43.000 but it's going to completely negate your ability to find a man right it's the 19 you're going to be an
00:24:47.700 old maid and you know eventually you're going to be an old maid right and you know eventually by by the
00:24:53.540 1930s when they've you know got the fear of stinking so many women that they've maxed out the the market
00:24:59.920 chair and they're like oh now we we still want to make more money they're like hmm what what should
00:25:04.940 we do oh dudes smell too but you know by this time they've spent a couple of decades uh presenting
00:25:11.580 this presenting deodorants and antiperspirants as a feminine product and so they have to like
00:25:16.360 dial up the the masculinity in their advertising strategies and so they put deodorants and antiperspirants
00:25:23.200 into like the manliest things they can imagine which in that case at that time was like a whiskey
00:25:28.000 jar so they're like selling deodorants out of whiskey jugs but also their their tactics still
00:25:35.060 rely on this thing called whisper copy right putting social fears of exclusion in men but instead of
00:25:41.980 focusing on on romantic exclusion they initially tell men because it's the 30s you know the depression
00:25:47.380 that they're going to lose their job or they're not going to get a promotion that effectively uh stinking
00:25:53.440 in the boardroom is going to hurt your career and nowadays you see you know both of these strategies
00:26:00.600 you know fear of social exclusion at work or or you know in love being applied to to everybody equally
00:26:06.700 but yeah it's that whisper copy this this fear and and you see this a lot in north america
00:26:12.880 let's talk about the smell of bo so the the quote you listed the guy described it as smell like a goat
00:26:19.280 how do scientists i mean you just there's people who they smell armpits for a living to try to figure
00:26:24.760 out what is yes how do they describe the smell of bo so i've always think it's like it smells like a
00:26:30.820 like a onion whopper burger what's the scientific description of it i have not heard that and i love
00:26:39.040 it but yes uh so when scientists uh sniff armpits they actually chemists actually measure the molecules
00:26:47.740 coming off of an armpit and they have actually found what's known as two top notes um and one
00:26:55.880 smells kind of goatee kind of like feedy goatee smell and the other one smells like overwrite
00:27:03.220 kind of like tropical fruit with a touch of onion so your onion whopper burger is not like totally off
00:27:10.740 and so these two top notes are you know the reason that when you go into an elevator and you're like
00:27:18.760 whoa there was a really stinky person here before me you know that it was a human instead of say you
00:27:24.740 know a stinky dog or or a stinky horse and those those two top notes are the things that dominate our
00:27:31.020 body odor even though there are actually hundreds of other odorous molecules that kind of like add to
00:27:37.420 our symphony of smell um and you know it's the kind of relative proportions that give you your
00:27:44.300 own odor print that is distinguishable from my odor print at least to a dog who's say tracking you versus
00:27:51.080 tracking me are some people smellier than others yeah yeah is that just genetics you know you know
00:27:59.860 it's due to you know the bacteria that you produce or not produce but that you recruit into your
00:28:06.680 armpits right so you know we know about our human microbiome you know we've got trillions of
00:28:11.300 bacteria in our inside our digestive tract but also all over our skin and you know for the most part
00:28:17.580 this this bacteria is acting as a really helpful defense against pathogens but also in our armpits
00:28:26.400 that particular ecosystem attracts what's known as a corinobacteria as well as you know staphylococcus and
00:28:33.360 a whole bunch of others but people who have a higher proportion of corinobacteria in their armpits
00:28:39.100 often have a more potent pong and the crazy thing is the craziest story i read in the book that really
00:28:45.820 stuck to me was the guy who wasn't really smelly but then he was amorous with a woman and then after
00:28:53.980 that he just smelled he had a bo problem and he kind of did he did some like amateur scientific stuff
00:29:00.060 and figured out i think i got some of her bacteria on me now i'm now i'm a smelly guy yeah well he
00:29:05.000 turned it into a phd project and effectively was super interested this was like in the early days of
00:29:12.740 microbiome research and you know although we've known for a long time that the actual source of
00:29:19.160 our odor is you know the byproducts from these microbes he thought okay well you know there's this
00:29:26.640 idea of probiotics right like can you introduce good bacteria and could i possibly reintroduce my
00:29:34.400 good bacteria because yeah he had this experience where after an amorous trist his whole body odor
00:29:41.180 changed dramatically and it was you know quite alarming for him and ultimately he managed to
00:29:46.980 repopulate his own body with his own bacteria because he's now in the process of his phd like analyzing
00:29:54.600 exactly the like microbial membership of his armpit right he has those skills and he ended up having
00:30:02.280 this t-shirt that he had used for years to paint you know when he had to like paint a room in a house
00:30:08.040 and it had i guess the you know bacterial populations of his pre-amorous trist self and so when he he put it
00:30:18.340 on to paint the house he noticed after that that he he had managed to turn his body odor back to you
00:30:24.980 know back to normal uh for him oh so this guy not as stinky the lady that he slept with stinky but
00:30:33.320 generally are there differences between the smell the bo smell of men and women so not a heck of a lot
00:30:40.140 but you know there are some studies that have shown that you know of these two top notes that i was
00:30:44.900 talking about that men have a higher proportion of the like stinky goatee odor i mean that women have
00:30:52.560 a higher proportion of the tropical fruit overripe oniony odor but quite honestly you know everybody
00:31:01.180 produces both of these things in their armpits but yeah it's it's you know slightly proportionally
00:31:06.700 higher for women to produce the oniony odor and men the goatee one well let's get to why you went to
00:31:13.880 moscow you went to a basically it was like a smelling dating thing basically people were getting
00:31:20.820 sweat and you were getting matched with another person based on your sweat and i think people
00:31:26.340 have heard this idea of pheromones right like you can buy cologne with pheromones and it'll
00:31:30.520 some sort of like love potion and people will be attracted to you oh my god we have to talk about
00:31:34.280 that after right well is there anything to this idea that there are pheromones in our sweat and
00:31:40.360 being exuded by our body odor that makes us attractive to other people well because a good
00:31:45.660 chunk of our body odor appears in the sweat glands that produce sweat that you know show up at puberty
00:31:51.900 and you know puberty is when we become sexually mature you know people think or people suspect that
00:31:58.740 there's got to be some sort of role that our body odor plays in you know mating and so people have
00:32:07.120 spent you know decades trying to track down a human pheromone out of our armpits and you know they've
00:32:15.700 gotten a lot of really tantalizing clues like i think a lot of people have heard of this one experiment
00:32:22.040 where women were given t-shirt samples worn by men and the women found the men to be most attractive
00:32:31.420 when their immune systems were different enough that should they procreate their progeny would have
00:32:40.000 a super strong immune system and if you you think about that it makes evolutionary sense because
00:32:44.520 you know for a lot of human history our major foe has been microbial right plagues infections things
00:32:52.160 like that and so it behooves us if you're gonna mate to mate with somebody who's gonna give your
00:32:58.400 your progeny a chance at survival by having a great immune system but even though you can do
00:33:04.800 these experiments by like you know asking women to pick you know the odor that they like and and you
00:33:09.720 know analyzing the blood of everybody and being like yes this would be a good immune match in terms
00:33:15.060 of like plucking out of our body odor a molecule that is you know known as a human pheromone that's
00:33:22.440 eluded chemists and actually when you know about what a sex pheromone in the animal kingdom does it
00:33:30.460 kind of is probably a good thing so for example a bombacall is this pheromone that moths make and when
00:33:38.560 a female releases bombacall literally every male in the vicinity makes a beeline towards her it is like
00:33:45.420 the scientific definition of a booty call or wild pigs so when male wild pig breathes heavily on a
00:33:54.800 female in heat a set of pheromones called androsanol and androsanone that is like in his saliva and kind
00:34:02.960 of like percolates up in his heavy breathing when she sniffs that she immediately turns around and lifts
00:34:09.800 her rump in the like universal sign that you know it's time to start a family so that kind of like
00:34:17.640 instant you know reaction is you know a little bit alarming if you think about you know the human world
00:34:27.040 like it's just as well we haven't actually isolated a human sex pheromone because yeah that could be a
00:34:34.680 little dire and that hasn't stopped online entrepreneurs from selling kind of pseudoscience
00:34:41.160 potions that they call human pheromone colognes that like sound scientific and typically include
00:34:47.140 androsanol and androsanone so these are those wild pig pheromones and they are found in the armpits of
00:34:53.680 humans right but both men and women produce them equally so it can't be a pheromone right it can't be
00:34:59.260 a message from one you know for example biological sex to another but you know if you wear one of
00:35:05.560 those pheromone colognes you just might attract a female but it's going to be a female wild pig rather
00:35:11.860 than a female human and you know no judgment if that's your goal but yeah it's probably not what
00:35:18.240 most of the people buying those things want but in terms of like romance you know this kind of notion
00:35:25.020 of a human pheromone people say oh yeah you know i fell in love with him or her because of you know
00:35:31.100 the way that they smelt right about their unique odor print as opposed to what we know from the strict
00:35:38.620 definition of a sex pheromone which would work equally on literally every member of the human
00:35:44.080 species right it's not it's anonymous it's not unique it's not the thing that made you fall for
00:35:51.100 you know whoever you fell for as your one and only but so okay so basically there's the scientists
00:35:56.940 there's something going on because you know people can detect differences and i think was another study
00:36:01.240 too like men find the smell of women ovulating more attractive than women who aren't wasn't there a
00:36:09.480 study like that with t-shirts yeah so lap dancers yeah lap dancers got more tips they suspect there's some
00:36:15.720 kind of odor going so like scientists there's something going on but they just don't know what
00:36:19.440 basically is what what's going on yeah that is pretty much basically what is going on and there
00:36:25.300 are so many molecules percolating out of armpits that yeah it's it's been a long hard road and many
00:36:32.820 researchers have like really tried to to pluck out something that's like giving us a strict cue that
00:36:40.360 like i want to mate with you and that so far has you know been unsuccessful well another thing that
00:36:47.360 can get transmitted via our body odor is fear have we figured out yes have you figured out what fear
00:36:53.480 smells like so that's a super interesting area of research so it kind of stems from the fact that
00:36:59.740 a lot of law enforcement folks say that when a person comes in for questioning for interrogation
00:37:07.020 that they come in smelling like themselves but after interrogation after all those tough questions have
00:37:13.000 been asked everybody leaves smelling the same of this like strong potent anxiety odor and when
00:37:20.280 researchers have you know tried to follow up on that anecdote again they found really interesting
00:37:25.680 evidence that this is true so they they gave people tight white t-shirts to wear and put them in front
00:37:32.600 of a television and had them watch kind of a nature documentary and then had them watch a really scary
00:37:39.280 movie so that they produced you know just their normal pong and then like super stressed out scared
00:37:45.900 body odor and when they presented those t-shirts to a panel of sniffers the sniffers could distinguish
00:37:53.360 you know from perfect strangers who was stressed out and who was just stinky right like who who was
00:37:59.580 actually fearful and who was just smelling and you know the the folks that with probably the most interest
00:38:06.400 in this is the military because you can imagine if you have a bunch of soldiers in a tank and one
00:38:12.260 starts getting really scared that this odor is going to be detected by others and you know it might
00:38:18.460 spread fear when all of these soldiers really need to you know stay focused and and hopefully a little
00:38:24.600 bit unafraid and so the military is interested in plucking out this anxiety odor molecule so that they can
00:38:31.260 effectively capture it like you would capture like a poison gas and you know there's other kind of
00:38:36.280 more dystopian applications that you can imagine you know if you figured out what that odor is the
00:38:42.380 one that is like this the smell of fear you could use it you know on crowds to do crowd control so
00:38:50.400 again chemists have been trying for a long time to pluck out that molecule they haven't so far been
00:38:55.880 successful but they are quite close well let's talk about deodorant and a person's a big circle back to
00:39:02.580 that so it became a thing in america the turn of the 20th century they're using the whisper copy saying
00:39:07.460 you'll be an old maid or a bum if you don't use deodorant but there's a difference between deodorant
00:39:13.620 and antiperspirants what is the difference and let's talk about antiperspirants you've been hearing
00:39:18.120 a lot about that uh that antiperspirants are bad for you and should use a natural deodorant
00:39:22.680 what does the research say about that sure so the main difference between deodorants and antiperspirants
00:39:28.940 is how they work to thwart sweat so deodorants have antiseptics in them and so effectively what
00:39:37.080 happens is you put on deodorant and you kill all the bacteria in your armpit including the ones that
00:39:43.120 cause odor right whereas antiperspirants plug your sweat pores in your armpit which include both like
00:39:51.060 the apocrine the ones making that waxy sweat that like bacteria like to eat and also just you know
00:39:57.400 the wet stuff that comes out when you're you're exercising and so antiperspirants work by literally
00:40:03.280 cutting off the food supply to the hungry bacteria and in doing so prevent odor from being formed and
00:40:11.540 that's why antiperspirants though also help you avoid wet patches whereas deodorants are just dealing
00:40:18.820 with odor and the way that antiperspirants plug pores and have always plugged pores like literally the
00:40:26.300 very first antiperspirant products relied on aluminum salts so it used to be aluminum chloride now it's a
00:40:34.680 more complicated aluminum salt but you know there's a lot of people who have fears about putting on a
00:40:41.320 product that's got aluminum in it in part because you know aluminum in in high amounts is a neurotoxin
00:40:48.140 that being said you know in terms of our earth we have you know evolved on a planet where aluminum is
00:40:56.720 one of the highest percentage metals in the mantle and a lot of the food for example that we eat like
00:41:03.520 sesame seeds even potatoes have high amounts of aluminum in them and so our body has evolved ways
00:41:12.100 to rid itself of of aluminum and that's usually through the kidney which filters out nasty stuff
00:41:19.080 not just aluminum from our blood and you know dispatches it out in pee and so because of this
00:41:26.700 like concerns about aluminum being a neurotoxin it is a neurotoxin there's been worries that you know
00:41:34.420 if you put on deodorants that you're going to up your body burden so much that it will give you
00:41:41.360 you know neurological problems or alzheimer's and you know all the research has been done on this for
00:41:48.280 decades and shows that there's really not a strong correlation at all between wearing antiperspirants
00:41:55.480 and alzheimer's it's not something to fear yet it kind of keeps coming back and actually the european
00:42:02.540 commission has a scientific committee that looks at consumer products and they recently revisited the
00:42:09.420 issue and forced the cosmetic care industry to to do some pretty sophisticated experiments to see
00:42:16.060 whether putting on antiperspirant effectively gets aluminum into your bodies at a level that is
00:42:24.260 dangerous and and they found that there was no cause for concern and you know those studies were
00:42:30.000 were published in 2020 so you know yeah aluminum is not great to ingest but we are getting it in our
00:42:38.220 bodies from eating and you know from all sorts of other things like lipstick and other things have
00:42:43.820 have aluminum in it but yeah it's probably by wearing antiperspirant every day it's probably not
00:42:50.140 you know pushing that aluminum body burden to to the point of of concern that being said i you know i
00:42:56.960 mix and match so you know when i have to you know for example stand up in front of a whole bunch of
00:43:02.340 people and i don't want to have sweaty patches because i'm like you know nervous i'll sometimes
00:43:07.760 wear antiperspirant and you know if it's a day where you know i don't have to do anything particularly
00:43:13.440 huge but i don't feel like smelling my own bo i'll you know put on deodorant so you know i i don't
00:43:19.460 think it's a huge cause for concern but yeah it has been one for for many years so we we sweat to keep
00:43:26.440 cool and it's an automatic process you have no control whether you sweat or not but cultures
00:43:32.320 around the world and across time they've come up with the practices where they can basically create
00:43:38.300 an environment where they purposely sweat so i'm talking saunas sweat lodges you know asian cultures
00:43:43.800 have similar like hot being really hot why do you think this is a universal across humanity where we
00:43:49.620 just want to sweat i mean what is it about getting really hot and sweaty that feels good
00:43:53.580 yeah we crave that catharsis and i think part of it is that you know when you work up a sweat
00:44:01.620 you effectively even say you go into a sauna or a jimjilbang in korea or a hamam in in the middle
00:44:08.580 east um you are effectively forcing your heart into a little tiny workout right because you go into this
00:44:17.220 really hot room and in order to cool down your heart starts beating fast to move the hot blood
00:44:25.260 in your interior out to the surface of your skin so that it can be cooled down by sweat evaporation
00:44:30.800 right so you you effectively get your heart pumping and that has knockdown effects where you know you
00:44:37.920 produce those same happy hormones that you get when you exercise profusely or go for a run the runner's
00:44:44.220 high the endorphins you also have like epinephrine that's that's being produced and so you do actually
00:44:50.100 get a biochemical high when you sweat profusely in a sauna so i think that there is this you know
00:44:56.880 feelings of joy and catharsis um that you get when you sweat in a sauna and also that you get if you
00:45:03.520 like really work out hard and have that you know euphoria that post-workout euphoria something you
00:45:10.120 didn't mention it doesn't detox oh yes that is the biggest myth this yeah if you ask me like what
00:45:16.320 is my you know my biggest sweat pet peeve it's this notion that sweating is a way to detox and that's
00:45:25.600 so totally wrong and it like reveals a fundamental misunderstanding of how our bodies work so remember
00:45:32.320 how i said that sweat is sourced from the watery parts of blood yes so if you were to detox by
00:45:40.960 sweating right where a detox the idea of a detox is like you get all the crap that's circulating around
00:45:46.700 your body out of your body right so if you were to detox by sweating you would literally have to
00:45:52.900 get rid of all the liquidy parts of your blood you would have to sweat out all your wet parts of blood
00:46:00.680 you would have to effectively dehydrate yourself at which point you would dry up and die that just
00:46:05.860 doesn't make sense instead our bodies detox using the kidney right so our kidney filters out all the
00:46:13.620 gunk in our blood right and dispatches out all the bad stuff in pee and anything that's coming out in
00:46:20.720 sweat is just incidental so yes certainly you can sweat out some some nasty things that are circulating
00:46:26.800 in your blood if they happen to be there but also you're sweating out you know glucose which your
00:46:32.020 body uses as energy and hormones anything that's in that liquidy part of blood and so this notion that
00:46:38.300 sweat is a detox strategy super super wrong and it's really good that we don't detox by sweating
00:46:44.320 because yeah you don't really want to dehydrate and die okay so yes sweating does remove stuff from
00:46:51.140 your body but that's just incidental you're not going to be able to purify yourself with just sweating
00:46:55.660 so when you go to the sauna just enjoy the sauna simply because it feels really good to get hot and
00:47:01.180 sweaty enjoy that little workout you get in there the endorphins just do it for this joy of sweat itself
00:47:06.980 exactly yeah well sarah this has been a great conversation where can people go to learn more
00:47:11.320 about the book in your work they can go to my publisher's website norton or my own website saraheverts.com
00:47:19.500 or they can you know grab the book off a shelf and and read it well saraheverts thanks for time
00:47:25.100 it's been a pleasure thank you so much my guest today was saraheverts she's the author of the
00:47:29.820 book the joy of sweat it's available on amazon.com and bookstores everywhere check out our show notes
00:47:33.820 at aom.is sweat where you can find links to resources where you delve deeper into this topic
00:47:38.180 well that wraps up another edition of the aom podcast check out our website at artofmanliness.com
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00:48:25.400 you