Today we discuss how the rinse cycle in some commercial dishwashers might be negatively affecting your gut, how a groundbreaking new study might have found a solution to PTSD, and how video games have been proven to improve our executive functioning skills.
Today we discuss how the rinse cycle in some commercial dishwashers might be negatively affecting your gut, how a groundbreaking new study might have found a solution to PTSD, and how video games have been proven to improve our executive functioning skills.
Dangerous Dishwashers
PTSD Prevention
Game Brain
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Find episode transcripts here: https://curiosity-daily-4e53644e.simplecast.com/episodes/dangerous-dishwashers-ptsd-prevention-game-brain
NATE: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from Discovery. Time flies when you’re learnin’ super cool stuff. I’m Nate.
CALLI: And I’m Calli. If you’re dropping in for the first time, welcome to Curiosity, where we aim to blow your mind by helping you to grow your mind. If you’re a loyal listener, welcome back!
NATE: Today you’ll learn about how the rinse cycle in some commercial dishwashers might be negatively affecting our gut, how a groundbreaking new study might have found a solution to PTSD, and how video games have been proven to improve our executive functioning skills.
CALLI: Without further ado, let’s satisfy some curiosity!
[SFX: WHOOSH]
NATE: When we go out to eat somewhere, we expect our plates to be, you know, nice and squeaky clean to avoid germs and other grossness. But it turns out that the dishwashers used to make those plates clean come with a rather unfortunate side effect. The possible destruction of our gastrointestinal tracts.
CALLI: Okay. I think you actually got that backwards because you just said that a clean plate is responsible for the destruction of our gastrointestinal tract. That can't be right.
NATE: Unfortunately, that might be the case. It's it's not as straightforward as it would seem.
CALLI: Okay, Now I'm confused because I'm not going to eat off of a dirty plate. So how is a clean plate worse?
NATE: So most restaurants use commercial dishwashers, which circulate hot water and detergent for around 60 seconds at a really high pressure. But after that cleaning cycle, there's a second 60 second washing and drying cycle where water and a rinse agent are applied. Then the dishes come out to be dried. Now, are you starting to see a problem?
CALLI: Okay, so the chemicals aren't being rinsed off.
NATE: That's the worry. Yeah. So in many cases, potentially toxic substances are remaining on the dishes and then they dry in place on the plates. So when the dishes are used, the next time this dried chemical residue might just end up in your food, in your mouth, and in your gastrointestinal tract.
CALLI: Okay, so this is a worry, and I see that. But I want to back up a little because you're saying may and might. So is there a chance that this isn't happening? Like, how how common is this?
NATE: So there is a chance, but it seems like it's a small one. A team of researchers noticed that these commercial grade detergents can damage protective layers on the skin in the lungs. And they wanted to see what kind of effect the rinse agents had on the epithelial barrier in the gut. For anyone who doesn't know, the epithelial barrier is a protective layer of cells lining the intestinal tract that controls what enters the body. Any problem with the epithelial barrier can lead to a number of health conditions like food allergies, gastritis, diabetes, obesity, cirrhosis of the liver, rheumatoid arthritis, and on and on and on. So if the detergents are breaking down this barrier, it could be a huge problem for diners everywhere.
CALLI: All right. So I'll be totally honest. I am pretty much a homebody. So I kind of DoorDash a lot of my food, so it's less of a problem for me. But I could see how this could be a huge problem for people who love to go out to eat.
NATE: I mean, I enjoy going out to eat and it had never occurred to me before that my nice, clean looking plates might be causing problems. For these scientists to safely test this theory they used a newly developed technology consisting of human intestinal organoids and intestinal cells on microchips. This tissue forms a three dimensional clump of cells very similar to the intestinal epithelium inside of humans. And after using various biomolecular methods to analyze the effect of commercial strength detergents and rinse aids on these cells, they found that high doses of rinse agents straight up killed the intestinal epithelial cells. Even worse, several genes and cell signaling proteins were activated by the detergents that could trigger inflammatory responses.
CALLI: Okay. Is this in every detergent? Like is this something that we really need to be worried about?
NATE: Yeah, it is pretty much in every detergent because each one of them uses a specific compound called alcohol ethoxylates. Now alcohol ethoxylate are technically safe, they're considered…
CALLI: I don’t like that. I don't like it when you say technically.
NATE: Well, they're considered a non irritant surfactant, which means that it causes mild to no irritation upon contact with the skin. And it's not responsible for the previously mentioned skin irritation. But on the other hand, it's also the primary reason why safety precautions are listed on detergents. In other words, those harmful, if swallowed, may cause skin irritation. Keep out of your gosh darn eyes warnings. That's from these. So long story short, there's a very, very high chance that when you eat at a restaurant, you're getting something a little extra in your food and. A side order of alcohol and fork slates that might ruin your stomach a lot more than that burger you just eat. But that's also not even the worst part.
CALLI: Okay. I'm going to go ahead and say that normally if something includes the word alcohol in it and you're getting it for free with your dinner, a lot of people are thrilled, but I do want to know how this gets worse.
NATE: Not the kind that they like.
CALLI: Yeah.
NATE: So unfortunately, this chemical can also be found in detergents used at home as well.
CALLI: Great.
NATE: So many dishwashers available to use at home do have a third rinse cycle. But many don't. Around 68% of American households have a dishwasher in the kitchen, and about half of those use the dishwasher between one and six times per week, with obviously larger households reporting more frequent use. But there's not a good way to properly count which dishwashers use or don't use the third rinse cycle.
CALLI: This seems like it should be a little more well known. Like, what can we do about this?
NATE: Well, the researchers believe that the best course of action for the everyday person is to talk about it, you know, eat at home, or if you have to see if you can replace your dishwasher if it doesn't have an additional rinse cycle. But of course, that's an expensive solution for a lot of people. However, this is possibly a big deal with huge implications for public health at large, and the researchers believe that this could be the beginning of the end for the gut's epithelial layer. So the best way to fix the problem is to get people talking about it.
CALLI: Well, if I was already kind of iffy about the notion of going out to eat anyways, you've kind of convinced me, and I'm going to probably try and eat at home a little bit more often and check to make sure that my dishwasher has a third rinse cycle.
[SFX: WHOOSH]
CALLI: One of the worst parts about going through a traumatic experience is that the memory attached to it never really seems to go away. But new research suggests that there is a way to change that for good. A single dose of hydrocortisone.
NATE: I thought that hydrocortisone was a steroidal anti-inflammatory. They use it for getting rid of like redness and itching or swelling from skin conditions.
CALLI: Yes. Yeah, I, I actually use it myself. I have eczema, so I use hydrocortisone cream. That is definitely its most common use when it's taken as a topical cream. But this can also be used to treat conditions like high blood calcium, thyroiditis, rheumatoid arthritis, dermatitis and asthma. It's kind of a one size fits all medicine for a ton of different ailments. So a team of researchers at Translational Psychiatry thought could it work for something psychiatric to like, say, persistent distressing memories, which are a common side effect of post traumatic stress disorder? And the answer was, what do you think?
NATE: Since we're doing a story on that, I'm going to go for a yes.
CALLI: Yes, the answer is yes.
NATE: Okay. I mean, I know we've done stories in the past about PTSD treatments, new things that they're figuring out and coming up with. But since then, like, we haven't seen a lot of progression in those treatments. So this is interesting that we've got something else to talk about. Why hydrocortisone?
CALLI: Okay, so since one of hydrocortisone side effects is a strengthening of how memory is formed, it seemed kind of like an obvious place to start. So PTSD is actually unique among psychiatric disorders because there is a known cause for it, a traumatic event that sets off a series of events in the brain. This includes the so called re-experiencing or A.K.A distressing involuntary memories, as well as in some very extreme cases, true flashbacks. Since we know the cause, it was believed that hydrocortisone would interrupt the processes that create hyper strong trauma memories.
NATE: Okay, I guess that makes sense. But now my question is, how do you go about testing something like this.
CALLI: Through a study, as everything is. This one was an eight day study. A team got together 120 healthy, 18 to 35 year old volunteers recruited at random into two groups, experimental and placebo. Each group had vitals checked, were given a set of psychological assessments of their mental health to check for depression, anxiety, dissociation and sleep quality before the real fun began.
NATE: Wait, they didn't actually traumatize these people on purpose, did they?
CALLI: Okay. No, no.
NATE: That's too invasive of a study.
CALLI: No, that would be unethical. Thankfully, the experiment didn't involve actually traumatizing anyone. So day one participants watched a stressful movie as a substitute for a traumatic experience. Yeah, there you go. After the movie was over, the researchers gave capsules with over 30 milligrams of hydrocortisone to the experimental group and identical placebos to the control group after about 2 hours. Participants were all asked to start pressing a button on the device whenever they had a memory of the traumatic movie. For the next six days, they needed to complete a memory diary whenever thoughts of the movie popped into their heads.
NATE: I mean, that's not usually how I watch movies and think about them later. But, you know, more scientific in this case.
CALLI: Okay. So yes, but within a few days, memories related to the movie became less frequent, but the reduction was much faster in the group that took hydrocortisone. This was expected and kind of hoped for. But while intrusive memory frequency was the same on average on the first day in both groups, the difference in frequency became larger every day to the point that they had to be confirmed with statistical tests from the fourth day onward.
NATE: All right. That sounds like pretty good information and good data. And I'm glad they didn't actually traumatize these people, but there’s one problem I think I still have here, a movie isn't real life. Like, is this going to work for people coping with actual trauma?
CALLI: Okay, I know we say this a lot on the show, but nobody knows yet, including the researchers who admit that movies might not adequately, quote unquote, “mirror the phenomenon seen following real life traumas.” So the study concludes by asking questions of whether hydrocortisone is effective in trauma victims before admitting there is no simple answer. But, results were promising enough to merit further research. And another clinical trial is set to begin testing one very high dose of hydrocortisone on a group of self-admitted sufferers of PTSD. So the answer could become simpler soon.
NATE: All right. Well, it's always good to get more data.
CALLI: I mean, yes, obviously, knowledge is power, but in this case, if hydrocortisone ends up being successful at treating PTSD, that would introduce a cheap, affordable way for properly treating something that isn't currently treatable successfully. So, here's hoping that the results stay promising and we can begin treating trauma at a much wider scale soon.
[SFX: WHOOSH]
NATE: I've got a thought that's either going to seem really obvious or really absurd to you. Hardcore gamers are better at decision making and quicker with reaction time than the average person.
CALLI: Okay, but as a gamer, I have to know, does it depend on the sort of game it's going to be like? Is it Zelda is a Final Fantasy? Is it Donkey Kong? Is it Minecraft? Is it League? Don't tell me it's League. Is it World of Warcraft? Like, what are we dealing with here? Okay, but anyways, I would say that I'm going to lean more towards neutral on this one. You're telling me that gamers are better at decision making quicker with reaction time? I get that. On one hand it makes a lot of sense that people would be more focused because of video games. It's literally all reflex and muscle memory based, but on the other hand, saying it's good for everyone. That seems a little suspicious to me.
NATE: I mean, clearly the people who are playing League aren’t better decision makers. They are playing League… and they continue to choose League.
CALLI: We're going to get slammed.
NATE: Unless League is owned by Discovery, in which case it's a great choice and way to go. Guys, nailed it. All right. It might sound a bit off, but a new study from the International Journal of Environmental Research and Public Health found that young adults who play video games consistently have an improved sense of executive functioning, which is what we call behavior related to decisions and reactions. For years, there's been a bit of a stigma related to gaming, so the results of this study go a long way toward wiping away some of the negativity.
CALLI: Okay, now I am really paying attention. What do you mean?
NATE: So most video game studies focus on the negative effects of gaming for too long. Specifically, researchers are usually trying to answer the age old question of do violent video games make young gamers more violent in their day to day lives? And the link between the two things is minuscule at best in some studies and nonexistent in others. So researchers out of the University of L’Aquila wanted to expand what is known about the positives of video games by looking into attention, performance and decision making without setting a control in the study for a video game genre.
CALLI: So how do they even measure executive functioning in these gamers?
NATE: So first the researchers sent out fliers in person and over social media looking for test subjects, and they recruited 38 university students with an average age of 23. Half of the participants were labeled experienced gamers who play 11 hours per week on average. And the other half were casual gamers who play an hour and a half per week on average. And participants entered a lab setting and took computerized assessments to figure out their level of skills.
CALLI: Okay, so first of all, I have to back up. You're telling me that an experienced gamer is playing 11 hours per week on average? Because I can test that.
NATE: Yeah, maybe. Maybe that was like 11 and up. It does say on average.
CALLI: 11 a day. A little bit. No, I'm kidding on that one. But I mean, that's close to.
NATE: That sounds unhealthy.
CALLI: I would say you've got at least several hours a day. Anyways, that's just coming from a gamer myself. But I am curious about the level of skill here. Like, were they having them play apps? Was it was it actual like handheld console games? Were they sitting them down and watching them play Halo? Like how did this work?
NATE: So this is general tests like not not ability to play video games. So like one was a dice game similar to a high stakes gambling situation you'd find at a casino. Another one was a task switching test where they'd be given a task to complete as quickly as possible before being assigned another. And there were a lot of tests like these. But one thing quickly became clear The experience gamers, regardless of the type of game played, were more alert, accurate and faster at attention tasks, and they were also much better at decision making.
CALLI: Okay, so that is interesting. Did they compare any of the data to people who I don't know, don't play at all?
NATE: Actually, no. And that's one of the limitations the researchers admitted toward their study, since they only focused on two types of gamer and the other problems with the study were the small sample size and the single gender being studied.
CALLI: Okay, I immediately hate it. So this focus was only on male gamers, wasn't it?
NATE: Yeah. The results of the study are interesting, but super one-sided. I'd be curious to see how the results fare with not only non-gamers, but other genders as well. What's interesting is that the study is statistically more likely to repeat this outcome if you added women and non-gamers into the mix, though, another study performed a few years back revealed that people with excellent executive functioning are more likely to play video games anyway.
CALLI: Okay, so the study is a bit one sided, which is disappointing, but that doesn't mean that the effort put forth was wasted, right?
NATE: No, not at all. This study contributes in a pretty meaningful way to two outcomes. It leads to the stigmatization of video games as an art form, and it also paints them as a tool for betterment. If being skilled at video games increases your capacity for executive functioning, that means there are good resources to help people help themselves. As the researchers say in their words, “These results can be a useful starting point to develop new and innovative executive training protocols inspired by video games.”
CALLI: Well, whatever the results are, I'm going to go play more Final Fantasy.
NATE: Sounds like a plan.
[SFX: WHOOSH]
NATE: Let’s recap what we learned today to wrap up. A recent study has revealed that alcohol ethoxylates, a common ingredient in industrial detergents, isn’t being fully washed off of most restaurants’ plates, leading to a breakdown of the gut that can lead to you being diagnosed with everything from obesity to cirrhosis. What’s worse is this can happen in certain home washers, too! The solution? Replace every dishwasher, and make sure all plates are carefully rinsed.
CALLI: Rashes, asthma, arthritis - and PTSD? A new study suggests that the anti-inflammatory drug hydrocortisone might be a successful treatment method for people suffering from PTSD. The experiment is admittedly imperfect, but the results are promising enough that further experiments are proceeding that might hopefully find a surefire way to treat traumatic memories and feelings!
NATE: Video game-s have the power to change the world! Or, at least, your capacity to make decisions more quickly. That’s according to a new study that correlates a high level of “executive functioning” with your level of weekly video gaming. So the next time somebody tells you to put down the controller, you can tell them “hey man. Science says I’m just improving my EXECUTIVE FUNCTIONING SKILLS.”