Caffeine: How Much Is Too Much?

9:55Prof. Sachin Shah:So just to get like real nerdy here, it's not that caffeine is binding onto these receptors and going, let's go, brain get excited. It's rather the lack of adenosine, the lack of sleepiness that wakes you up.

10:12Dr. Astrid Nehlig:Yeah, and that's what we like about caffeine, right? Like that is the whole point that it wakes us up. And it's not just about being awake. We actually have a lot of evidence that caffeine helps us be more alert, more focused, and helps us to react to stuff faster. This has been quite extensively studied. This is clear.

10:30Prof. Gregory Marcus:So if I take a stupid example, but you are facing a lion. If you have been drinking caffeine, you will react faster and you will run away before. It could save your life. Yes, absolutely. could make a difference and save your life.

10:52Dr. Astrid Nehlig:And scientists have actually tested this. They gave free coffee to people who were visiting the zoo that day, and then they opened the lion cage. Amazing. And they got away?

11:03Prof. Sachin Shah:They got away?

11:04Dr. Astrid Nehlig:Some got away, some didn't. That's right.

11:06Prof. Sachin Shah:Those in the placebo group were less likely to get away. We are joking.

11:11Dr. Astrid Nehlig:No, there are no lions. But there is one small study that suggests that caffeine really could save your life. So this study, researchers had people stay up really late and then drive a car on the highway in the middle of the night. This is a real car and a real highway.

11:27Prof. Sachin Shah:Oh, my God.

11:28Dr. Astrid Nehlig:They had a driving instructor in the next seat who could take over control if things were getting bad.

11:33Prof. Sachin Shah:My goodness.

11:33Dr. Astrid Nehlig:So the scientists were counting how many times people veered out of their lane when they had placebo versus when they had coffee. And it turns out the coffee made a big difference. the number of times people veered over the lane went way down after people had coffee. Okay. The powers of caffeine. Yes, right. And then I found this study that just made me laugh because it's just such a funny concept. The scientists really wanted to find out if coffee can make us appreciate humor more. When we are sleep deprived, we kind of lose our sense of humor or it takes a hit. So the researchers were wondering, would caffeine give us back our sense of humor or improve that?

12:15Dr. Astrid Nehlig:Uh-huh. And I don't know if you know this, Wendy, but there is a scientific test of sense of humor.

12:21Prof. Sachin Shah:Oh, my gosh. That was entirely my next question. What is the joke that scientists ask that they're like, if you find this funny, you have a good sense of humor?

12:31Dr. Astrid Nehlig:Then you're operating on full cylinders. Yes. Yeah, so they would show them like two different pictures and ask which picture is funnier or more podcast appropriate. They would have them read two different headlines, fake news headlines, and ask which is funnier. So here's an example. I'm curious if you're going to get it right.

12:48Prof. Sachin Shah:I feel very cocky about my sense of humor.

12:51Dr. Astrid Nehlig:Okay, so here's the example. Which of these two headlines is funnier? Veterinarian investigates failed panda mating. That's headline one. or panda mating fails, veterinarian takes over. That's headline two. Which is funnier?

13:07Prof. Sachin Shah:Headline two is funnier because it suggests. I mean, headline one isn't funny at all, right? But headline two suggests.

13:15Dr. Astrid Nehlig:Just something really, really disturbing, actually. And the third headline is veterinarian f***ed panda.

13:28Dr. Astrid Nehlig:You're right. Right. It is the second headline.

13:30Prof. Sachin Shah:Yes.

13:31Dr. Astrid Nehlig:According to science, that is objectively funnier, which I guess it is.

13:35Prof. Sachin Shah:Also, I'm so proud of them for being a little bit naughty.

13:39Dr. Astrid Nehlig:Well, it turns out that the caffeine in this case did not help people.

13:42Prof. Sachin Shah:Yeah, I totally forgot we were talking about caffeine.

13:47Dr. Astrid Nehlig:So bottom line, caffeine may not improve your humor, but we have lots of evidence to show that it's not a myth or a placebo effect. Like caffeine does help us wake up, stay up, stay alert. So that brings us to something that people actually worry about with caffeine, that it's keeping you too awake, that it's messing with your sleep.

14:09Prof. Sachin Shah:Yes, I have worried about this too. And in fact, cut down on caffeine because I've been worried about this.

14:15Dr. Astrid Nehlig:So let's meet Gregory Marcus.

14:17Prof. Gregory Marcus:I'm just going to move my dog. Come on.

14:20Dr. Astrid Nehlig:He's a cardiologist and a professor of medicine at UCSF. If you could be any caffeinated product, which caffeinated product would you be?

14:28Prof. Gregory Marcus:Oh, cappuccino, no doubt.

14:30Prof. Sachin Shah:I guess he sees himself as serious on the bottom, but like a little bit frothy and sweet on the top. You know, he didn't refer to himself that way.

14:39Dr. Astrid Nehlig:But based on my conversation with Greg, I would say that's an accurate description of him.

14:43Prof. Gregory Marcus:Buttercup has been removed for the moment.

14:49Dr. Astrid Nehlig:So Greg did this, like, pretty unique study where he got people to either drink coffee or not drink coffee at random. And then he was able to, like, precisely measure exactly how that affected their sleep. Ooh, okay. So they recruited about 100 coffee drinkers in San Francisco. They put a bunch of stuff on them. They wore a Fitbit, which measured how well they slept and their steps. and they wore a portable heart monitor.

15:17Prof. Gregory Marcus:So it's essentially like a very big Band-Aid and it goes on the chest to the left of the sternum, essentially.

15:25Dr. Astrid Nehlig:And like interestingly, in the middle of the sticker, there's this big button.

15:29Prof. Gregory Marcus:We instructed them, just push that button whenever you have a cup of coffee or a caffeinated drink.

15:35Dr. Astrid Nehlig:So you have your coffee and you hit your button. And one way they made sure that people were doing what they were supposed to do, you know, not drinking coffee if they weren't supposed to that day. They had everyone in the study get this app on their phone that allowed the team to monitor their location so the team could see if they visited coffee shops. So if they went to a coffee shop on a day they weren't supposed to have caffeine, that would be highly suspicious. Would there be like a bright, a button goes off in your office, like a flashing red light? Would they get an electric shock?

16:11Prof. Gregory Marcus:Yeah, that's a good idea. Interesting idea.

16:15Dr. Astrid Nehlig:That's exactly what I was thinking. Well, luckily for the people in the study, we didn't design it. No. We did not get shocked.

16:23Prof. Sachin Shah:Oh. Okay. Okay. So I'm going to go out at a limb here, Rose, and say that on average, coffee did affect people's sleep.

16:33Dr. Astrid Nehlig:Yes. But the key question here is how much? Because there is this idea that coffee just really robs you of your sleep. Well, in reality, Greg found...

16:43Prof. Gregory Marcus:On days where people were randomly assigned to consume coffee, that evening, they on average slept 30 minutes less.

16:53Dr. Astrid Nehlig:Yeah, so on average, if they were in the coffee drinking group, they had half an hour less sleep. And Greg could even dive into the research and figure out how much sleep each cup of coffee cost these people. And it turns out about 15 minutes of sleep.

17:09Prof. Sachin Shah:Okay, so loosely for every shot of espresso or just like regular coffee, you'll get around 15 minutes less sleep a day. Uh-huh. Okay. Yes, but— That's not terrible. That's not— Oh, oh, oh, but—

17:23Dr. Astrid Nehlig:There is an important caveat, which is that Greg found this really varied from person to person based on their genetics. So on top of all that other stuff, Greg also took saliva samples from people and worked out if they had these genes that make them either a fast or a slow metabolizer of caffeine. And he found that the slow metabolizers lost closer to an hour of sleep a night on average. Oh, wow. And the fast metabolizers lost basically no sleep at all. Huh.

17:56Prof. Gregory Marcus:So people who say, oh, yeah, I can have a cup of coffee at night. I go right to sleep. they may be really telling the truth.

18:03Prof. Sachin Shah:My mom proudly says that she could drink coffee, like, at dinner time, and it will not affect her sleep, to the point where she will mock me when she wants a coffee at 4 p.m. and I say, too late for me. Mama Zook vindicated once more by a Science Versus episode.

18:20Dr. Astrid Nehlig:Well, it's like you're both right. She's right that she can have a coffee late at night, and you're right that you can't. You're probably both right. Okay.

18:29Prof. Sachin Shah:But you know who isn't, right? Is those people online, influencers, I don't know what we want to call them. Anyway, who have these like definitive statements about how much coffee you're allowed to drink and you need to stop at 10 a.m. and only drink two cups or whatever they're saying. Like actually what the science says is this is very dependent on your genetics. And those blanket statements are kind of bollocks. Yeah.

18:58Dr. Astrid Nehlig:Okay, so that's sleep. But Greg's study looked at something else that people don't necessarily associate with having a cup of coffee. And that is exercise. So on top of measuring sleep, he also measured how many steps they took every day. And?

19:16Prof. Gregory Marcus:On days randomly assigned to coffee, participants, on average, exhibited a thousand more steps on those days.

19:25Dr. Astrid Nehlig:Wow, that's a lot.

19:26Prof. Gregory Marcus:It is a lot. And in fact, there's other evidence that that magnitude of a difference may be meaningful in the long run in enhancing longevity.

19:38Dr. Astrid Nehlig:Oh, wow. Yeah. For example, one study found that older women who take 5 ,000 steps a day live longer than similar women who took 4 ,000 steps a day. Oh, that's cool. And it's not just step count. We actually have a lot of data showing that caffeine can help us athletically. So when people have caffeine before they exercise, they tend to go a little harder. So like people will be able to run for longer or, for example, do more squats. Cool. There's a study that looked at swimmers doing a 1500 meter race. So that's almost a mile. And it found that having some caffeine beforehand shaved 23 seconds off their time compared to a placebo.

20:21Dr. Astrid Nehlig:And having caffeine before exercise is considered safe as long as you don't overdo it. Like the equivalent of one or two coffees before exercising.

20:30Prof. Sachin Shah:Wow. And so why is that happening?

20:35Dr. Astrid Nehlig:Well, you know how caffeine can boost your dopamine. So that might be like putting us in a better mood so we can work harder. And we also know that caffeine can kind of turn the dial down on feelings of pain. That's why some painkillers have caffeine in them. So maybe athletes aren't feeling the burn quite as much. And then finally, there's some evidence that caffeine can actually increase the amount of calcium getting released by your cells, which could make your muscles work better. Wow. So, Wendy, do you still feel guilty about your coffee? Oh, no.

21:13Prof. Sachin Shah:So, thus far, no. But at the same time, we haven't really talked about risks yet.

21:20Dr. Astrid Nehlig:Good point. So, next we're going to talk about, is caffeine addictive? And what's going on with the scary stories we hear about people dying after drinking energy drinks? And that's coming up just after this quick coffee break.

21:42Prof. Gregory Marcus:Snoring? Gasping during sleep? Feeling fatigued? Ask your doctor about ZepBound Terzepatite, the first and only FDA-approved prescription medicine for moderate to severe obstructive sleep apnea, OSA, in adults with obesity. ZepBound is a prescription medicine used with a reduced-calorie diet and increased physical activity to help adults with moderate to severe obstructive sleep apnea, OSA, and obesity to improve their OSA. ZetBound is approved as a 2.5, 5, 7.5, 10, 12.5, or 15 milligram injection. ZetBound contains terzepatide and should not be used with other terzepatide-containing products or any GLP-1 receptor agonist medicines.

22:23Prof. Gregory Marcus:It is not known if ZetBound is safe and effective for use in children. Don't share needles or pins or reuse needles. Don't take if allergic to it or if you or someone in your family had medullary thyroid cancer or if you've had multiple endocrine neoplasia syndrome type 2. Tell your doctor if you get a lump or swelling in your neck. Stop ZipBound and call your doctor if you have severe stomach pain or a serious allergic reaction. Severe side effects may include inflamed pancreas or gallbladder problems. Tell your doctor if you experienced vision changes before scheduled procedures with anesthesia, if you're nursing, pregnant, plan to be, or taking birth control pills.

22:56Prof. Gregory Marcus:Taking ZipBound with a sulfonylurea or insulin may cause low blood sugar. Side effects include nausea, diarrhea, and vomiting, which can cause dehydration and worsen kidney problems. Talk to your doctor. Call 1-800-545-5979 or visit setbound.lily.com.

23:35Prof. Gregory Marcus:Find out what it's like to be a long-haul trucker, a couples therapist, or an FBI agent, all on the podcast, What It's Like to Be.

23:49Prof. Sachin Shah:Welcome back. Today on the show, we are asking, should you quit your caffeine? Should you spit out your coffee, spill your tea on the floor, say goodbye to your energy drinks? Rose Rimler, senior producer at Science Persis, is telling us all about it. Hey, Rose. Hey, Wendy.

24:06Dr. Astrid Nehlig:So the next thing I want to dive into is this idea that you can get addicted to caffeine. You know, and I think a lot of that comes from this like terrible withdrawal that some people have when they stop it. Now, caffeine withdrawal is a real thing. And people who quit coffee all of a sudden can totally feel sick. Like about half of them will get a headache. This could be because caffeine restricts blood flow to the brain. And when we go off it, the blood whooshes back in. Oh, wow. Some people even feel like they have the flu and they feel like really tired and crappy. So send them help. So pray for them.

24:41Prof. Sachin Shah:Do I need to pray for them? Do I? Like if suddenly there was an apocalypse and they couldn't get their coffee, how bad would it be?

24:47Dr. Astrid Nehlig:All those symptoms, they go away for most people somewhere between two to nine days.

24:53Prof. Sachin Shah:Okay. So if they can survive for nine days, they'll be back to normal.

24:57Dr. Astrid Nehlig:Yes. Just hunker down in your bunker. Hunker in your bunker. Great. And it'll play itself out.

25:02Prof. Sachin Shah:Right. Okay.

25:03Dr. Astrid Nehlig:But back to this addiction thing. So, you know, you might reasonably call yourself dependent on caffeine if you feel sick without it. But that's not the same thing as addiction. With addiction, what experts point to is that you are using a substance even though it's bad for you. It has negative consequences on your life. Maybe you even, like, really want to quit and you can't. And I think right now, the general idea among scientists is that this is not a problem for most people. They don't really see any evidence of this negatively affecting people.

25:38Prof. Sachin Shah:Right, for most people. And then what about tolerance? Like this idea that you need to have more and more caffeine to have the same effect.

25:46Dr. Astrid Nehlig:Yeah, we typically don't really see that with caffeine. and one reason is probably that at a high dose caffeine starts to activate this other type of adenosine receptor in our brain that causes anxiety oh this is why you get all like jittery and like oh if you have too much caffeine there's sort of a threshold you can cross from all the feeling like alert and energetic and kind of good to oh now i feel anxious and jittery and and weird and one researcher I spoke to said that for caffeine specifically, this window, he calls it a window between the good and the bad feelings, is pretty short. So you can kind of easily tip yourself over when you've had more caffeine into that anxious feeling.

26:32Dr. Astrid Nehlig:And if you're starting to feel that way, many people would probably put down their third venti frappuccino of the day at that point. Yes. So there's kind of a natural cap for most people on how much caffeine we're going to drink every day.

26:47Prof. Sachin Shah:Yeah, yeah, yeah, yeah. You know, because recently I did, I was like, fuck it, I'm just going to drink more coffee. And it did make me feel anxious. And so I was like, no, no, no, just go back to one or two cups. Like just, yeah, this isn't, go for a run instead or whatever.

27:01Dr. Astrid Nehlig:Yeah, it's not like worth it to most people at a certain point. And, you know, this can be different if you're mixing caffeine with other drugs. That's more dangerous. But bottom line, caffeine is not considered a drug of abuse. There is no caffeine use disorder in the DSM, you know, the big manual for psychiatric disorders. It's been proposed, but right now it's not officially in there.

27:27Prof. Sachin Shah:Okay, so for now we could say science says caffeine isn't really that addictive.

27:35Dr. Astrid Nehlig:Is that where we're at? I think so. I think, yeah. Yeah, I think so. So thus far, all right, it doesn't, it's really not seeming like caffeine is that bad.

27:46Prof. Sachin Shah:And I'm trying to think why I thought caffeine was bad for you. I actually might have an answer.

27:53Dr. Astrid Nehlig:In the 90s There was news that Coffee was associated with Bladder cancer Oh really? But that has been debunked in more recent years Turns out it was not a real association But even if you don't remember That stuff about bladder cancer I think that sort of percolated So to speak in the culture And we haven't quite gotten over it Plus there's a lot of fears Around pregnancy and caffeine Right. And that is something to think about because we know that caffeine can cross the placenta and get to the fetus. And so drinking a lot of caffeine when you're pregnant isn't recommended. But, you know, health guidelines from around the world, they say you can have one or two cups of coffee a day if you're pregnant.

28:37Dr. Astrid Nehlig:Right. You know, overall, just putting aside pregnancy, I walked away feeling pretty reassured about caffeine. Because here's something that I thought was like really kind of great. So it turns out that people who drink coffee have a lower risk of Parkinson's disease, depression, type 2 diabetes, and heart disease. Really? And although we once thought coffee was carcinogenic, more recent studies have found that it actually might reduce your risk of some cancers. What? Like liver and breast cancer. Are you kidding me?

29:10Prof. Sachin Shah:Are you serious?

29:11Dr. Astrid Nehlig:Like, yeah, and even drinking coffee is associated with being less likely to die earlier. So the biggest benefits are seen in people who drink two to three cups a day. But even at higher amounts, we still have people apparently getting some benefit. Like one study looked at people drinking as much as eight cups of coffee a day and found they still lived a little longer than people who didn't drink any coffee. Wow. Yeah, I mean, there aren't that many people that drink eight cups of coffee a day, so that's kind of a smaller sample size. But I think that point stands, that science suggests that coffee is not actively harming you.

29:47Dr. Astrid Nehlig:And caffeinated tea also seems to be good for us.

29:50Prof. Sachin Shah:I mean, are we sure? Are we sure about this? Like, why would caffeine, why would coffee and tea have these benefits?

29:57Dr. Astrid Nehlig:Nobody totally knows. It could have something to do with the exercise boosts you get from caffeine. Because like we said earlier, like walking more steps a day. But also, it could be that it's not really about the caffeine. It's about the other stuff that's in the plant. So the coffee bean, the tea leaf. There's a lot of stuff in there that's really good for us and is anti-inflammatory and has antioxidant potential.

30:22Prof. Sachin Shah:Wow. I'm feeling very good about my coffees. I was not expecting this from science, but thank you. Anytime. So then, I don't want to crap all over this party. Is that how that phrase goes? Yes.

30:41Prof. Sachin Shah:Rain on your parade? Yes, yes. Is that what I mean?

30:48Dr. Astrid Nehlig:It's a very, it's a visceral expression.

30:53Prof. Sachin Shah:You see, I don't know if I have a good sense of humor. I just laugh so much at my own jokes.

30:59Dr. Astrid Nehlig:I know a test you can take. Great.

31:01Prof. Sachin Shah:Okay, but what does this all mean about the energy drinks issue? Because to change the tune, to get quite serious, there are these stories about energy drinks killing people. So what does this mean?

31:22Dr. Astrid Nehlig:Which is the opposite of what I just told you about coffee, right? Yeah. Well, a lot of times what people say is the problem is that energy drinks are dangerous because they are packed way too full of caffeine. Right.

31:35Prof. Sachin Shah:Right.

31:36Dr. Astrid Nehlig:But the funny thing is, when you look at the labels, many of them really don't have that much caffeine in them.

31:42Prof. Sachin Shah:Oh, how much caffeine is in your average energy drink?

31:45Dr. Astrid Nehlig:Well, okay, so like Chuck Schumer said that Prime Energy had an eye-popping amount of caffeine. So I looked up the label of Prime. It contains 200 milligrams of caffeine.

31:56Prof. Sachin Shah:What? 200? What, like two shots of espresso? That's it? That's it? Yeah, two or three, depending on how you make them. I love that you were like, so I went deep undercover. I bought a prime and I turned it around and I looked at the label.

32:14Dr. Astrid Nehlig:And of course you can overdose on caffeine. The toxic effects are thought to start at 1 ,200 milligrams, which is about six cans of prime. And there are case reports of people drinking a bunch of energy drinks and being hospitalized. But here's where things get mysterious. There are reports of people, often younger people, dying after drinking less than that, which suggests this isn't just about caffeine. And Professor Sachin Shah saw reports like that in the news and thought,

32:50Prof. Gregory Marcus:Hey, there's something going on here.

32:54Dr. Astrid Nehlig:You know, it was actually a little bit sad at points talking to Sachin because he's actually been in touch with the parents of kids who have died after drinking energy drinks.

33:03Prof. Gregory Marcus:Yeah, we've had emails from other countries. One where somebody's like, I have kept the drink that my kid drank from the time when they drank it just in case it helps future scientists. I'm happy to give you that drink.

33:20Prof. Sachin Shah:That's heartbreaking.

33:21Dr. Astrid Nehlig:Yes. So Sachin, who's a professor of pharmacy at the University of the Pacific in California, he wanted to know why would anyone die after drinking a couple of energy drinks?

33:33Prof. Sachin Shah:Yeah, yeah.

33:34Dr. Astrid Nehlig:So to get to the bottom of it, he did the study where he got people to drink a couple of energy drinks and then looked at what their heart was doing. Because typically what we see in these cases is that someone's heart stops beating shortly after drinking energy drinks. So he got these volunteers to come into the lab. He hooked them up to an EKG.

33:53Prof. Gregory Marcus:Many people see this on TV shows when they have somebody in the hospital. They're connected to this screen. They're lying in the hospital. They show this squiggly line. Yes, yes. That's looking at your heart rhythm.

34:05Prof. Sachin Shah:Beep, beep, beep. Yes. Just to avoid us putting the sound effect in. Always thinking ahead. Okay, so they've drunk the energy drinks.

34:13Dr. Astrid Nehlig:And then he monitored them.

34:15Prof. Gregory Marcus:And one hour, two hours, four hours, six hours, and 24 hours.

34:19Dr. Astrid Nehlig:And he was looking at this particular part of our heart's rhythm that's called the QT interval, which is it's basically looking at how long it takes your ventricles to contract after every beat. And if this takes longer than normal, it can throw your heart into something that's called fibrillation, which is like instead of going squeeze, squeeze, squeeze, your heart starts quivering like a nervous chihuahua. And the problem with that is that your heart isn't actually pumping out any blood, and you can die.

34:53Prof. Sachin Shah:Oh, man. Okay, so did the energy drinks muck up the QT interval?

35:01Prof. Gregory Marcus:So, yeah. So, you know, what was interesting is in that first study, we found that energy drinks were prolonging the QT interval by 10 milliseconds.

35:10Dr. Astrid Nehlig:A follow-up study he did found this again, that the energy drinks extended the QT interval by, this time, six milliseconds. And Sachin points out that several drugs have been pulled from the market for prolonging the QT interval by six milliseconds.

35:25Prof. Sachin Shah:Mm, wow. Okay, so if I were to drink the equivalent caffeine from what he gave them, but in coffee, would my QT interval be extended like that?

35:38Dr. Astrid Nehlig:No. Studies have also looked at this for caffeine or for coffee, and they don't find the same thing. And actually in Sachin's study, in one of his studies, they included a caffeinated control, and it didn't do the same thing to people's hearts.

35:54Prof. Sachin Shah:So if energy drinks are doing this, why aren't heaps of people, like, getting heart attacks and dying after drinking energy drinks? I mean, millions of people must be guzzling this stuff, and only a handful have died or so?

36:10Dr. Astrid Nehlig:Yeah, I mean, it's not like anyone in Sachin's study had to be rushed to the hospital. Right, right. But the thinking here is that there are some people who could be really vulnerable to this. Like people who have heartbeats that already have kind of a long QT interval. And then the energy drink might extend it even more. And that could tip you over into Chihuahua territory.

36:31Prof. Sachin Shah:Right, right.

36:32Dr. Astrid Nehlig:One study actually found this. It gave energy drinks to people with a heart condition like that. and found that the drinks extended their QT interval in such a way it was actually dangerous.

36:43Prof. Sachin Shah:Uh-huh. So then can we go back to that point? Like if it wasn't the caffeine, if it's not the caffeine doing this, then what is it in energy drinks that's causing this?

36:58Dr. Astrid Nehlig:Yeah, I mean, in Sachin's study, they tested a couple different brands. They both had caffeine, taurine, which is an amino acid, in a supplement called glucuronolactone, which is found in a lot of energy drinks, like Red Bull.

37:11Prof. Sachin Shah:So this is the ingredients. This is how we get wings. Is that right?

37:15Dr. Astrid Nehlig:This is the wing recipe. Yes.

37:17Prof. Sachin Shah:Okay.

37:19Dr. Astrid Nehlig:So all this stuff together seemed to extend the QT interval. But then I found this one study that tried to really get to the bottom of which ingredient is the bad guy here. So they basically deconstructed a Red Bull and had people drink a few of the components, one at a time while they were hooked up to an EKG, just like Sachin. And after drinking the Red Bull, volunteers had a prolonged QT interval. But none of the individual components did this. What? Neither did the combination of caffeine and taurine together. So I asked Sachin about this. What do you think is in these energy drinks that causes these changes?

37:57Prof. Gregory Marcus:That's the million-dollar question.

37:59Dr. Astrid Nehlig:Science!

38:02Prof. Sachin Shah:You know, I was having coffee with my brother the other day, and he said there is always a point in a Science vs. episode where the scientist says, Dad, we don't really know what's going on. And I guess this is that point.

38:14Dr. Astrid Nehlig:Yeah, we've arrived at that point in the episode. And, of course, it's also really hard to say what's going on when this is probably very, very rare, you know. People drink energy drinks all the time, and very few people land in the hospital.

38:29Prof. Sachin Shah:Okay, so here is what I think I have learned from this episode, Rose Rimler. Tell me how I did. Let's hear it. And if I pass the test, I have a good sense of humor. Is that what we learned? Yeah.

38:44Dr. Astrid Nehlig:Yes.

38:45Prof. Sachin Shah:Case closed. Caffeine truly does make me poo very quickly. Nice. It can affect your sleep, but very much dependent on genetics. So dare I say, listen to your body and not what people online might be telling you about what you should and should not do with caffeine. And meanwhile, it might reduce your risk of depression if you're drinking coffee and tea. What'd you say? Cancer, Parkinson's. Diabetes. Diabetes and energy drinks. There is something weird about them. So if you are looking for a boost, it's safer to go with tea or coffee. How'd I do?

39:27Dr. Astrid Nehlig:A plus, people. I'm not surprised. And you, as a prize, I sent a case of Prime to your house. Great. Don't drink it all at once.

39:40Prof. Sachin Shah:Excellent. Cheers, Rose.

39:42Dr. Astrid Nehlig:Cheers.

39:44Prof. Sachin Shah:But before you go, Rose. Rose. Rose. I'm here. I'm still here. Okay, okay. How many citations are in this week's episode?

39:53Dr. Astrid Nehlig:This episode was the first time I've ever opened so many tabs that my browser stopped displaying them. Like I reached the limit of how many tabs I can have opened. That is so many tabs. It's like getting to the end of your Instagram feed. You're like, oh, no.

40:11Dr. Astrid Nehlig:But what is in the script is that we have 118 citations.

40:16Prof. Sachin Shah:118. Okay, yes. And if people want to see these citations, find out where we got all of our info from, where should they go?

40:24Dr. Astrid Nehlig:They can click the link in the show notes that will send them to the transcript.

40:28Prof. Sachin Shah:Excellent. And I guess while people are scrolling through Instagram and hitting the end, if you have hit the end of your Instagram, you could just come over to Science Versus. Was that a segue of like picking up social media accounts? Thanks. Yeah. We are at science underscore VS. Yes, I'm on TikTok at Wendy Zuckerman. And we will see you next week. Thanks, Rose. Thanks, Wendy.

40:58Prof. Sachin Shah:This episode was produced by Rose Rimler with help from me, Wendy Zuckerman, as well as Nick Delrose, Joel Werner and Michelle Dan. We're edited by Blythe Terrell. Fact-checking by Sarah Baum. Mix and sound design by Bumi Hidaka. Music written by Bobby Lord, Bumi Hidaka, Emma Munger and Peter Lennon. Special thanks to all of the researchers that we spoke to for this episode, including Dr. Brian Saunders, Dr. Sergi Fauré, Professor Andreas Hines, Professor Christine Curran, Dr. Erica Loftfield, Dr. Felix Oberhofer, Dr. Alan Wayne-Jones and Dr. Vijay Yadav. Extra special thanks to Jason Vitler-Sill and the Zuckerman family.

41:34Prof. Sachin Shah:Science Versus is a Spotify Studios original. You can listen to us for free on Spotify or wherever you get your podcasts. We are everywhere that podcasts are. I guess we're in a lot of places. If you are listening on Spotify, follow us and tap the bell icon so you can receive notifications whenever we put out a new episode. And if you like us wherever you are listening, please give us a five-star review. I'm Wendy Zuckerman. Back to you next time.

42:06Dr. Astrid Nehlig:Now, it's not all fun stuff like rectal probes. Name of your sex tape? It's not all fun and rectal probes. No, the sex tape is called All Fun and Rectal Probes.

42:22Right.

42:23Dr. Astrid Nehlig:We can't only talk about rectal probes on this episode. We also, unfortunately, have to talk about some unpleasant stuff.