Stuff You Should Know - Taste and How it Works

Episode Date: July 20, 2010

Taste seems like a pretty simple sense, but scientists are still trying to figure out exactly how it works. Josh and Chuck explore the complexities of taste, from definitions and physiology to tongue maps and supertasters, in this episode. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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Especially if you're selling something. Squarespace is everything to sell anything. They have the tools you need to get your business off the ground, including e-commerce templates, inventory management, a simple checkout process, and secure payments. Whatever you sell, Squarespace has merchandising features to make your products look their best online. So head on over to Squarespace.com slash SYSK for a free trial and when you're ready to launch, use offer code SYSK to save 10% off your first purchase of a website or a domain. Brought to you by the reinvented 2012 Camry. It's ready, are you? Welcome to Stuff You Should Know from HowStuffWorks.com. Hey and welcome to the podcast. I'm Josh Clark. With me as always is Charles W. Chuck Bryant. Put us together and you've got the podcast duo that's huge in Dallas.

Yeah, you got a lot more than that. Got about 400 pounds of hairy goodness. Yeah, slippery hairy goodness. Yeah, 400 pounds and I'd say at least 100 pounds of that is hair. Yeah, right? I wish. If I could get a haircut and help solve that problem and a shave. You did get a haircut. We have the same haircut. We have matching hair. It's like, it's called the five guard. Yeah, four guard. Is there a five? Yeah, I go with five. I do a four and then I do a three on the sides. Just feather it up.

You know what's weird? This conversation? Yes. Yumi says that she can smell a new haircut. You know how you can smell a freshly cut lawn? She says she can smell a new haircut and I'm like, no one else on the planet can. We even looked it up. There's no reference on the entire internet to smelling a new haircut, right? Maybe she's a super taster, smeller. I was going to say, I don't think that that translates to taste, Chuck. Okay, but is that her segue? I think that works kind of right. I mean, consider this. You know, when you've ever smelled something

and you're like, I know what that would taste like, but it wouldn't taste like that. But you can tell how something would taste or how you would imagine it would taste. The reason it's so easy to imagine that is that smell and taste are as similar as any two senses are because they're both reactions to chemicals, right? Old factory smell, gustatory. We'll probably say those words, taste. Very nice. I love gustatory. And the types, there are different types of molecules that react to different types of senses, right?

Yes. So you have an odorant that we smell that reacts with our odor receptors. Right. And then you have a gustants or tastants. Yes. I prefer tastants. I'm a gustant guy. Are you?

Uh-huh. That react with the taste receptors on our tongue, right? Right. But because they're so close, you know, you really actually can't have one without the other, which if you've ever had, you know, any industrial accident associated with chlorine, you'll know that not only can you not smell any longer, you can't taste any longer. Yeah. Or that's why food tastes weird when you have a cold.

Like Patty and Selma, they had an accident. I can't remember what happened, but everything tastes like cardboard to them. It was like this off-handed thing they said in The Simpsons, but like after it sunk in, I'm like, that's the most depressing thing I've ever heard. Right. They were big smokers, too. Yeah. I guess that was my Patty and Selma.

Since you mentioned it, we should go ahead and point on a little factoid here that worms and other invertebrates, actually, there's no distinction between taste and smell. Yeah. They're like, why put any kind of division up? We're just going to call it all one thing, but... My head looks like my butt, so what's the difference? Right. They distinguish, though, between volatile and non-volatile organic compounds.

Right. Right? Which means that if you paint a room and put a worm in it, it knows that you just painted that room. Right. If you got your hair cut. Right. Perhaps.

Yeah. So I guess we should talk about these GRCs, gustatory receptor cells, taste buds. That's kind of where it all happens. It is. And, you know, the taste buds are the little... Oh, I guess they're part of the little bumps on your tongue. Well, yeah, it's actually under that. Yeah.

Well, it's wrapped up in a package, right? Yeah. It looks like a little spring onion, like the butt of a spring onion. Or radish. It looks like a radish. It does. It looks like beet. Yeah.

It looks like one of those. Maybe even a weird garlic. Or, you know, it looks like here. It looks like a hot air balloon. It looks like one of those boxing things. Oh, yeah. Speed bag. Yes.

Nice chuck. Within this little, what's called a papilla. Papilla. Papida. Papida. Yeah. I don't think you're supposed to say it like that. Sure.

Within that, there's 50 taste receptors, and they're generally specialized taste receptors, right? They're the same kind of taste receptor in every papillae, right? Yeah. Mm-hmm. And so you've got 50 of those. Some basil cells, which are skin cells, they produce skin cells, right? Yeah.

Not basil is in the plant. Basil. That would be great if I had basil that lived in my tongue at all times. You would be turned on, remember? Oh, that's right. It's an ephrodisiac for men. Yes. Just for men, Joe.

Sorry. That'd be great if we were actually sponsored by things and we just worked them in like that. Yeah. Did we do one on that? We did. So you have about 50 receptors in this little papillae, some basil cells, and you have each receptor cell has a little hair sticking out of it.

Yeah. A gustatory hair. Right. It's not Italian, though. No, but all of it does sound Italian. That's, from what I gather from this photo rendition, is that that is what you actually see poking up on your tongue, right? The little round thing is actually the little gustatory hairs, isn't it?

That's what it looks like. It's coming out of the top of the speed bag. Right. And they come out of taste pores and it's the gustatory hair where all the actions take place, right? Yeah. That's where flavor and taste, well, that's where taste starts. Say you put a bite of steak in your mouth, right?

Your mommy. So the saliva is breaking down the meat. It's the first step in breaking it down. And it's breaking it into these little molecules called tasteants or... Gustants? Yes. Depending on your preference. And these molecules, bind to the saliva, are taken across the tongue and they stick

to the receptors that are generally designed to, if you believe in intelligent design, designed to create the sensation that we call taste. Or they just happen to match up if you don't believe in intelligence. Right, exactly. Just good luck. And, Chuckers, taste is much different from flavor, isn't it? Just to find taste in flavor, because this is a big thing. Yeah, flavor, I think Sarah Dowdy actually has stuff you missed in history class, if

I'm not a guest. She wrote this and the way she put it, which I thought was great, was flavor is sort of like a full body and we'll get into actually that stuff later with the gut cells. But flavor is a whole body experience. It's all your senses, including smell, obviously, tactile. And she said that what spicy food pain is factored in is one of the aspects of flavor. Yeah, I love that. So taste is this tasteant molecule wrapped up in your saliva smacking against a gustatory

hair. Yeah. It sends a transmission to your brain and your brain encodes it and says, ooh, mommy. Right? Right. Or salty. Right. There's different voices for each taste, as I'm sure you know already.

Oh, yes. Don't ask me to do sour. We will later. That's just the taste. The flavor is that the pressure that the steak puts on your tongue, the tactile sensation of the ends of the meat, is just kind of dancing across your tongue. Or if you like your steak rarer, medium rarer like I do, that just that lump of like warmish clothes, bloody flesh, right, yeah, and then like you said, pain too.

All of our vegetarian fans just turned off. Right. They're so disgusted right now. But that whole sensation is flavor and all these different sensations are going to the brain and the brain's like, oh, steak. Yeah. You know what I want to know? And actually just thought of this, what is the deal when you like eat a piece of cheese?

Someone will tell me this, I'm sure. Like you get a piece of sharp cheddar and it feels like your jaw locks up. You ever have that with certain flavors? No. Really? Your jaw lock? I know with like a really dill sour flavor, I'm like, no, I'm talking about Jerry. Have you ever had that with cheese?

Jerry's asleep. Like I'll put a piece of cheddar in my mouth and my jaw just like clenches, like noticeably clenches. I have no idea what you're talking about. Jerry just said yes. Jerry doesn't know what we're talking about at all. Well, that may be, you know, we're going to talk about super tasters in a minute. There are different types of tasters we found out.

It's not the same for everyone. So maybe that's one of my, you know, my kinds. Right. And here's a little spoiler about super tasters. The key to super tasters, they have more taste buds. Yeah. That's huge. Boring.

Yeah. All right. So Chuck, there are of course what every school kid knows are primary tastes, right? Yeah. Sweet, salty, sour, bitter. Right. Back in our day, that was it. That's all the taste you get, right, Sonny?

Yeah. And what was it, salt, sweet, sour, bitter? Yeah. Right. And then what's funny in the Western world, for a good century after a fifth taste was discovered, we still stuck to these four and didn't recognize that there was a fifth one. Right.

Americans. Because the researcher was Japanese and his work was never translated to English. So in about 1900, 1901, a Japanese researcher named Kikune Ikeda. Yeah. Thank you. Akita? Akita. Akita?

Yeah. In the early 1900s, he discovered something called umami, which means a delicious savory taste in Japanese, right? Right. What he was doing was he was cooking some of that Japanese seaweed that we both love. And he was like, you know what, this is neither sweet, salty, bitter, or sour. So he started researching it. And he found out that he isolated the glutamic acid and found out that it had its own gussetory

receptor. So he was like, this is legit. Right. And he said it in Japanese, which is the problem. Right. Yeah. And everybody was like, what did that guy just say? Umami?

What the heck is that? Let's go back to the World's Fair in St. Louis. Right. That's my scream. Yeah. And one of the reasons also that it was never really investigated over here is umami is much more of a flavor that is in Japanese dishes. Like you said, seaweed.

Right. Huge, but also over here we have tomatoes and umami flavor. Meat. Meat. Yeah. Savory. Sure. Right.

And Akita's research was backed up in the West in 1985. A little later. Yeah. When some researchers started to try to isolate the taste for monosodium glutamate. And remember umami is glutamic acid, right? Yes. So glutamate, glutamic acid. So they're trying to isolate the flavor of MSG, which is a pretty distinct savory flavor.

Yeah. And they found that no combination of the primary taste, bitter, sweet, salty, sour could replicate MSG. I wonder how they did that. I don't know. There's a lot going on in flavor science that is fascinating. Yeah. Huge.

Yes. I'm curious, but they basically, yeah, you're right, they came away with nothing. All the combinations, they can't account for MSG and its magical properties, the flavor and calories and uh, is it supposed to like make you feel full or something? You know what they say? I don't know. No. With MSG?

Yeah. I thought that was the deal with, or maybe that was just an urban legend. People are like, you know, Chinese food, MSG makes you feel all full. No, it makes you feel sick. It's called Chinese restaurant syndrome. Oh, that's right. Chinese restaurant syndrome. I know with me, if I eat MSG, it feels like a claws grabbing the top of my stomach hurts

so bad. Yeah. It's, a lot of people are allergic to MSG and of course Chinese restaurants are famous for using it. They don't use it a lot anymore, do they? I don't think so. And most restaurants actually advertise whether or not they use it. Well, they advertise that they don't use it.

They don't advertise like with MSG because it's seen as a bad thing. But remember, we got a listener mail in once from somebody whose family owned a bunch of Chinese restaurants and was like, you guys talk about Chinese restaurant syndrome because MSG is found in like snack chips or, you know. We get all the blame. Right. And it's just, it's not just Chinese restaurants and a lot of Chinese restaurants have stopped using MSG.

So there you go listener. We satisfied that two year old listener mail. Yeah. Just now. We finally get around to it. And did you hear what a pro I was? I didn't cite the snack chip that he used as an example. That's how good we're getting.

Wow. Yeah. My mind is blown right now. Mine too. Yeah. Like you said in 2002 actually is when Akita's study was finally translated into English. So many years even after 1985. Oh.

Yeah. Right. So from that point, Umami was accepted as the official fifth taste. Right. And then, but think about it. So that's like a century because the taste map, which we'll talk about the tongue map, that was established in 1901 about the time that Akita was coming up with the Umami, but it was just that sweet, sour, salty, bitter.

Right. Right. So for a century, the taste map didn't change. Right. And then in 2002, Umami's accepted in the West finally. Right. And then it seems like the floodgates open. Right.

All of a sudden like they're like, well, wait a minute, if there's a fifth taste, maybe we haven't been paying enough attention. Like fat is apparently now the sixth primary taste. Right. Leave it to the French. Um, there are new studies now, Joshers, that says that, uh, well, they, they think they've identified fat as its own thing. Like humans have a taste for fat and that the funny thing I thought, if you have a high

sensitivity to that taste, you eat less fatty foods. You know, Chuck, that is, I think, um, a really, that's something that's going to become what gets taste research, it's funding. Is obesity and diabetes and stuff like that. Yeah. What I found is people who are, when you're talking about super tasters, super tasters who taste sweet things tend to eat less. Yeah.

Um, tasters who, uh, a lot of people don't really detect the fat as much. People who do have less body fat, you said, lower body mass index. Yeah. Um, so you don't eat the foods that you taste the most. Yeah. That's interesting. It's very interesting. Yeah.

They did the, the lady did the one study on a super tasters and I think she found that women in their 40s, at least, I guess that was her set was, um, they were, uh, they gained less weight or they were, you know, slimmer than non-super taters, but she didn't find because they were eating less of it. Yeah. But she didn't find that in men, which I thought was odd. I guess men are just like, we just shovel whatever. Yeah.

Bring it on. Yeah. And it's like, oh, you want me to lose some weight? Watch, I'll just drink water for a day and there's 50 pounds shed. Right. Yeah. So Chuck, now it's 2010. Yes.

If you stick out your tongue, please stick out your tongue, Chuck. You know, I bit my tongue almost all the way off when I was a kid. Oh, I see that. Wow. It's like Frankenstein's tongue. Yeah. Sort of. So, all right, Chuck, stick out your tongue, please.

Still? Yeah. Um, so we've got umami. Uh-huh. We've got sweet. Yeah. Sour. Uh-huh.

Bitter. Yeah. Salty. Yeah. Fatty. Yeah. Yeah. And, uh, a lot, it looks like the, that's a pretty fat tongue, Chuck.

Yeah. Yeah. This is worse than the beet-boop. I like the beet-boop. Um, and we also have, uh, they've recently discovered that we actually have specialized receptor cells that detect carbon dioxide. Yeah. Well, should we finish the tongue map real quick, at least, and why it's bunk?

Sure. Uh, because you were pointing, but people can't see you point, Josh. So the classic tongue map says that bitter is in the back, sour is on the side, salty is on the front edge, sweet is on the tip, and umami, they're throwing on the posterior and saying that. That's where that is. Yeah. They're like, that real estate's open.

That's where we'll put umami. Yeah. Stake your claim. But they're fine. They've also found that, um, that there's fat somewhere, has to go in there somewhere, right? Yeah. Do they know where that is yet?

Uh, I still knew. Yeah. It's too new from what I understand, right? Right. But I think it's, it's not just, it's, I think it's going to take the, the tongue map away that's going to be done away with because there are primary tastes certainly, but they're finding that's, you know, the whole tongue map when it was invented in 1901. D.P.

Hannig. Yeah. A German researcher. Um, basically what he did was to say areas of low sensitivity were depicted like there was no sensitivity. Yeah. Like there's those lines that like there's actual borders. Right.

And yes, maybe this area of the tongue is higher in receptor cells for umami or sweet or bitter, but that doesn't mean that it's not found elsewhere on the tongue as well. Yeah. And so a lot of tastes are a mixture of all these. Number one. Well, sure. And all he did was interview people. He did.

Which I thought was odd. Yeah. His research was backed up in 1974 by Virginia Collings, right? Well, sort of backed up and sort of not. Well, it was kind of like revised, I guess. Yeah. He's like, yes, his, he, he was right in saying like this area has higher in sweet receptors than this area.

Right. So he could possibly put a tongue map, but maybe it was just kind of pushed the wrong way. Yeah. There's overlap. Yeah. Collings was the one who was saying like this is a lot, there's a lot of interplay going on, including CO2.

Let's get back. Can we talk about CO2 finally? Yes. Now is the time. That's pretty cool. I mean, you sent me this over the emails a couple of days ago and said, dude, you, you tapped me on the head and said, dude, you know that bubbly stuff? You think that's, that's what's making that taste in your mouth and it's not.

No. So there, we have a gene that expresses an enzyme that's meant to detect carbon dioxide in the bloodstream. Right. Yes. So you can break it down into useful forms. Right. And they've for forever, basically, we thought that anytime we drank a carbonated drink,

it was the popping of the little bubbles on our tongue that created that sensation. Uh-huh. Not so fast. They have put people in a pressurized chamber, hyperbaric chamber, right? No bubbles. So, soda that, yeah, has no bubbles present and people could still detect the carbon dioxide taste. Yeah.

So there's yet another taste. There's no place on the tongue for carbon dioxide and yet there's specialized receptor cells for detecting it, right? Yeah. Well, because they, like everything else, they said, this is interesting. Let's get some mice and genetically make them different and weird and test them out. Right. And they did that and they found it was the same receptor as sour, right?

Yes. So, the sour receptor basically doubles as a CO2 detector as well. They remove that in mice. Yeah. And also, they put a sensor into one of their nerves, which is pretty interesting in and of itself that we can do that. I know. It's crazy.

So, those combination, those series of studies led to this discovery that we have CO2 detectors. And what an important discovery that is. Right. And Chuck, it is. Is it? I think so. Well, that's the whole thing. It leads you to the question, Chuck.

Why do we have taste anyway? There's one obvious answer is that we are, we learn to eat by deriving pleasure from it and we associate some taste with, they're pleasurable, right? Well, yeah. But early man, it was a lot of times like warning systems. Well, this is the less obvious answer, right? Yeah. Like if they ate something sweet, they're like appealed to them.

It's, you know, it gives them a lot of calories and so that's a good thing. If they tasted something really bitter, it might be poisonous. Right. So, you should spit that out. Right. Sour could be spoiled. Sure. Something that was wrong.

Or it could be, you know, a sweet and sour candy, which is yummy. Right. If you're early man. Right. And with early man, we had yet to figure out a way to encode ideas and warnings about like not to eat something. Right. To, you know, the written word.

So we had to use our taste senses on our own. And we still, that's what's so cool. That's why I love evolution. All these years later, that's why we're still attracted to sweet things because that was survival. It gave you calories to live basically food energy. Right. But we have also gotten to the point where we are, you could say a reasonably fat society

here in the U.S. and you mix that together with health consciousness or self-consciousness especially. Yeah. And all of a sudden you have artificial sweeteners, which you would think is good for your body. But they found that there's a correlation between using artificial sweeteners. Right. And type two diabetes. Yeah.

Right. And they figured out through this investigation, they figured out that there are taste cells elsewhere in the body. It's not just the tongue. And we're getting this idea that not only are tastes, they're more primary tastes than we realize. Tastes are interplays of different receptor cells. Right.

And there's taste cells elsewhere in the body, in the gut specifically, but also probably in the pancreas, in the liver, in other areas. So these tasteant, these molecules that are boundless alive and that enter the gut, they start sending out other signals rather than meaty. Right. Like we were saying that the bitter taste might be something poisonous. Sometimes you'll eat something poisonous and it gets past the old tongue and you swallow it and that's when the guts taste cells kick in and that's why you might, like it might

spur vomiting all the time. Right. It triggers your vomiting reaction. Thank God. Yeah. That's one way. With the type two diabetes, with the sweet receptors in the gut are signaled by something sweet.

Yeah. They tell the blood to start absorbing insulin, right? Yeah. They tell the surrounding cells to start absorbing insulin or glucose, I'm sorry. Yeah. So insulin, which actually Chuck, you remember we've talked about before and I think whenever we talked about longevity, insulin's like the worst thing for your body. But we use it to go into cells, to basically open the cells so glucose can go be burned.

But if the glucose doesn't arrive, if there's no sugar eaten, and it's just an artificial sweetener, that signal is still triggered. The insulin still goes and jams open your cells, but nothing gets burned and the insulin levels go up and you have type two diabetes. So that's the tie between drinking like a diet soda and potentially leading to diabetes. Right. But isn't that interesting that we've figured out something new about taste, that it's all over.

I know. It's an all over sensation is what they're coming up with, right? That's crazy. So what else do we have, Chuckers? Well I think we finally need to just map out the supertaster thing just a little bit more. Because supertasters are pretty cool and how it all happened is really cool. Shall I tell the story? I'd like to hear the story, Chuck.

Way back in the 1930s, a scientist named Arthur Fox from Dupont was pouring some, and this is like every like OSHA, this is the worst nightmare when they hear stories about this laboratory stories like this. This dude was pouring some PTC, do you want to say the long name? I do, but I have to find it first. I'm not prepared to say it. It is phenol-theocarbamide. Yeah.

Very nice. Thank you. So he was pouring some of this PTC, it's an organic compound into a beaker and the way he described it was, he says it suddenly became a cloud that started shooting all over the room. And this is when OSHA is like, oh God. And it basically filled up this room and he was in there with his partner and his buddy was like, ah, ah, ah, it's awful, it's so bitter and he was like, what are you talking

about? Wow. That's not bitter. What do you mean? So when he heard the conversation, wait a minute, what's going on here? You had a really awful reaction and apparently I've seen studies on YouTube that they don't use PTC anymore because it's dangerous. But apparently it's so bitter, it's like the reactions are hysterical.

So he goes home and he starts putting this stuff on his family's tongues and his friends' tongues to see if they react the same way and he found that there's no rhyme or reason to who it happens to because it's a genetic trait. And they said they used to use this for, it's so specific of a genetic trait, they used to use it for paternity cases, like up through like the 1970s. Holy cow. Yeah, they said it's the most like, one of the most common Mendelian traits right up there with like eye color and blood type is whether or not PTC makes you like freak out

with bitter. Really? Yeah. That's a terrible test. Yeah. And it's a specific gene, there's a dominant allele for the TAS2R28 gene, right? Yes. They've isolated that?

Yes, 70% of people, this is what's weird, 70% gets the bitter taste, 58% of Australians and 98% of Native Americans in both North and South America, almost all of them have that reaction. Really? Yeah, isn't that crazy? Yeah. I don't even know what it means, I just thought it was interesting. In 1991, there was a researcher from Yale who coined the term supertasters, right?

Yes. And it's not just bitter and it's not just people who react to PTC or PCP, right? Everyone reacts to PCP. Yeah, but whether or not you beat up 10 cops I think is probably, that's a paternity test too. Let's see how you react to PCP. It's not just this bitter taste, right? You can have a supertaster who really tastes sweet things, really tastes umami, really

it's a primary taste, right? Yeah. That's just heightened. And like we said, the spoiler is, you just generally have more of these papillés. Yeah. You have more taste buds of the certain types than other people. Yeah, and it can be a good thing, like to have a heightened sense can be good in certain respects, but it also apparently like coffee and Brussels sprouts and really sweet and

spicy things, supertasters can't handle that a lot of times, so it's a curse as well as a blessing. Yeah. I would say. I can't handle broccoli, but it has nothing to do with taste. You know, I like all of it. I've been eating beets like crazy lately. Yeah?

Ever since I beat salad? Yeah, I've been making my own beet salad. Yeah. I've been grilling beets, a little balsam, a little olive oil. I did not have that, I'll have to try it. Put it on the grill and then the next day you're gonna think you need to go to the doctor, but it's just the beets. That's all I'll say.

Okay. So that's pretty much it. Like we said, if you're a supertaster also, it supports that aversion to foods that you can taste more than other people, supertasters who are sensitive to sweet, tend to eat less sweets, etc. But they also avoid leafy greens, which is not good. No, you gotta have that. Yeah.

Especially if you're pregnant. Actually, we forgot to mention, they don't use PTC anymore, but they do use PROP as the test now, which is a synthetic compound. They just call it PROP. Right. And they use it in thyroid medicine, right? Yeah. But now that's the standard supertaster test to see if you have that bitter reaction to

that. So they just give you thyroid medicine? Or they drop some PROP on your tongue. I don't know how it works. Weird. And then lastly, Chuck, the answer to why a lot of stuff tastes like chicken. I don't know this. Surprise me.

Well, at least at Cornell, using gas chromatography, they have isolated 1,000 concentrations, chemical concentrations. And 900 of them are chicken? That contain tastants that the human tongue can taste, or that the human brain can sense its taste. And they used to think it was hundreds of thousands. They're like, no, it's just thousands. And chicken is like 999 of them.

Really? Well, I made up the chicken part. That's my theory. Okay. And my theory is that it's because there's only 1,000 instead of 100,000. There's your answer right there. And then lastly, Chuck, that also makes me wonder if there's 1,000 chemicals. And they used to think it was hundreds of thousands.

So there's hundreds of thousands of chemicals out there, but we can only taste 1,000. It's kind of like light. We can only see within a certain band of light. Makes you wonder how things that we can't taste taste. You just chew on that one. And if you want to know more about taste, go to howstuffworks.com where you can type the word taste in the handy search bar. And also, this is, I think, requisite listening for a molecular gastronomy podcast that we'll

do sometime in the future, don't you think? Yeah. I'd love to do one on that. All right, Chuck, then you know what time it is, right? Listener mail or are we doing some sort of Facebook or anything? Oh, wait. We got our big announcement. We got to do.

That's right. Thank you for reminding us. Go ahead. Our Atlanta event, right? Yeah. We're going to do an Atlanta thing similar to what we did in New York because we got called out by all the Atlanta folks, like, you go to New York, New York, New York. What about Atlanta?

Yeah. Well, we're like. Yeah. We kind of have to. So yeah, we're going to do trivia night, right? All comers can come take us on. Yeah. We'll figure out the details, but we're looking for venues still.

Yeah. We're going to do people for details. If you are in Atlanta and you have some connections with what might be a good venue to host our trivia, please get in touch with us. Yeah. So yeah, we'll keep you posted. If you have any suggestions, comments, whatever about the Atlanta thing, email us. And now, Chuck.

Well, it should be sometime in August. We should point out. Okay. Very nice. We don't have a lockdown yet, but look forward in the next, like, six weeks. Right. Now, listener mail, right? Yeah.

All right, Josh, I'm going to call this a rare shout out because we don't do these very often. Yeah. Shouts out. Shouts out. Something like the new William Sapphire. Hi, Josh and Chuck. My husband and I are huge fans of your podcast.

We eagerly wait every Tuesday and Thursday so we can hear what you have to say. I guess it proves our fans. Yeah. Now, you can be my heroes as well. Next Saturday, July 17th is my husband's 24th B-day. Chuck, this is very kind of you. I know. We don't do this very often.

We just bought our first house. He made me promise not to buy him anything, I guess, because they just spent all their money on a house. Yeah. I wonder if you give him a shout. I know you don't do this often, so let me tell you why he's cool enough to get a one-of-a-kind birthday greeting. His name is DJ Vile.

Seriously, he's in your Facebook group, V-I-L-A-D-J-Vile. And I don't think that's... Is he a DJ? No, I think that's his name. His name's like Donald James Vile or something. Well, if he ever becomes a DJ, then... He's all set. Yeah.

He's like, just call me me. He listens to every one of your podcasts. He's a huge Simpsons fan. Yeah. What do you mean, eh? Well, I mean, those are good, but that's not a reason to shout out. Okay. But these are.

Okay. He ran a 10K as a green man. I know. I saw that. Wow. Is that a Rootsuit? It was either... Yeah, I think Green Man and the Rootsuit are one and the same.

Okay. So he actually ran a full 10K as a green man. Yeah. And lastly, he'll be spending his birthday driving to present his research entitled this, Refraction Variability of Lung Tumor Motion Using 4D Cone Beam CT at a Physicist Medical Conference in Philly. And this dude is 24 years old and he's doing that. I know.

My brain is melted. So, with that, on the 17th, happy birthday, DJ Vile. Happy birthday, DJ Vile. Thank you very much for listening. And Julie, your wife sounds like a very kind woman. She does. And good luck presenting your findings. Yeah.

Happy wishes for your new home. Mazel Tov. All right, Chuck. Thank you for the listener mail. Now it's time for a shout out to Kiva. Kiva.org, slash team, slash stuff you should know. Or if you just go to community, you can search stuff you should know. Right.

Join our Kiva team. We are on a mission to raise a quarter of a million dollars in loans. And we're making it. And we're doing it with... How many... We have hundreds of thousands of stuff you should know listeners. We have, like, 2,000 in change members on the Kiva team. Yeah, so there's, like, 180,000 of you out there that are really disappointed.

Right. And there's just this... But on the same token, we're very, very proud of the 2,000 in change who are members of this stuff you should know Kiva team because, so far, they've raised 170,000 and then some. So far. And we're on the way to... We're on the team. Yeah, we are included.

But there's people on there who put us to shame. Yeah. And they're, like, heading it up on their own, too. Yeah, there's some really great people on there. Somebody was, like, somebody got a bonus at work and made a loan. Somebody, I think, an auto repair wasn't as much as they thought, so they used the difference on Kiva. They made a loan on Kiva.

I'm not that good of a person. People that just make us look, like, vile. Like, I find 20 bucks on the ground and, like, if I'm not hungry, I might think about not spending it on beer and giving it to Kiva. I have a similar problem. Yeah. So, thumbs up to our Stuff You Should Know Kiva team. If you want kudos from us, you can join it yourself.

Again, that's www.kiva.org slash team slash stuff you should know is a very welcoming community of people, right? Great people. We're on Facebook. We have a Facebook page with 12,000 and then some fans, and we are extremely active on it. Yeah. It's actually a fun Facebook page.

Right. I should say Chuck is way more active than I am, but I go on. We hold on to the Twitter thing. Yeah, I do Twitter, but we're both on there, but Chuck is really, really good about responding to people's comments and questions and stuff. So if you want to interact with us, especially Chuck, you can go to facebook.com slash Stuff You Should Know. We're also on Twitter.

That's why, SK Podcast, you can follow us on our stupid musings and we get caught up in hoaxes and stuff and have to eat crow thanks to me. Right. Or we get told you got to take that down. You can't say that. Right. Yeah. We're going to get everybody in trouble.

And then what's the last thing? There was one other thing. Oh, I don't look at the given t-shirts. Yeah. The t-shirt contest is over. We have five winners and you can buy every single one of these awesome t-shirts, five different Stuff You Should Know designs at the Discovery Store. Go to store.discovery.com and search Stuff You Should Know and it'll bring up all five

t-shirts. Yes. And that's it, man. That's it. If you have anything cool to say to us or you want to hear it, put it in an email, send it to StuffPodcast at HowStuffWorks.com. For more on this and thousands of other topics, visit HowStuffWorks.com. Want more HowStuffWorks?

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