MR. KOJO NNAMDIEnergy drinks promise a boost, a buzz, a pick-me-up. Some even promise to give you wings. But watchdog groups are voicing concern about the way the products are marketed. And recent reports from several federal health agencies have raised questions about the product's safety, while makers maintain the drinks are no more dangerous than a morning cup of coffee.

MR. KOJO NNAMDIHere to help us understand what's driving the popularity of energy drinks is Dr. Scott Shapiro. He is the director of Cardiac Arrhythmia Services at George Washington University Hospital and a professor of medicine at the George Washington University School of Medicine and Health Sciences. Scott Shapiro, thank you for joining us.

DR. SCOTT SHAPIROThanks for having me, Kojo.

NNAMDIAnd joining us from studios in New York City is Barry Meier. He is a reporter for the New York Times where he covers issues related to business, public health and the law. Barry Meier, thank you for joining us.

MR. BARRY MEIERThanks for having me on, Kojo.

NNAMDIBarry, they vary depending on brand and type but generally speaking what exactly is an energy drink?

MEIERIt's basically a dressed up, hyped up version of caffeine that has a lot of other additives in it. Things with weird names like taurine. But basically they boil down to caffeine often in a synthetic form that's sold for 2 to $3 a can.

NNAMDILet's ask our listeners why they use energy drinks, 800-433-8850. Do you drink energy drinks? Why do you opt for them over coffee or soda, 800-433-8850? Barry, where do these drinks fit into the bigger picture of nutritional supplements and functional foods?

MEIERWell, they're marketed both as nutritional supplements and as beverages, depending on how the companies want to promote them to the public. But they're basically part of a broader trend where consumers are being promised products that are going to give them some kind of aid, some type of advantage, keep them up, make them able to work. And they will do that in terms of the caffeine that they have in them. But in terms of giving them, you know, a performance edge, if you will, I'm afraid that's probably not going to happen.

NNAMDIScott Shapiro, the energy boost most common in these drinks, as Barry has pointed out, is caffeine. Exactly how does it affect the body and what's the general guidance on how much caffeine is safe?

SHAPIROYeah, caffeine binds to adenosine receptors in the brain and elsewhere. And how it works is that it's a competitive antagonist. So it blocks adenosine from binding to those receptors. Adenosine can cause you to relax, to bring you down a little bit. And so blocking these receptors ends up resulting in a hyped up state, an adrenaline state, and we all know the effects of that after we drink our cup of coffee in the morning.

NNAMDICaffeine, however, is not the only stimulant in most energy drinks. What other ingredients are common and what do they do?

SHAPIROThat's a good question, Kojo. Guarana is a -- comes from a plant that's found in the Amazon. And it is listed as an ingredient in many of these drinks, or some of these drinks. It has about twice the amount of caffeine as a coffee bean does so it's listed separately but in effect it's just another form of caffeine.

SHAPIROThere are other things as well in these energy drinks. Taurine, in much higher doses than we get in our normal diet, is a nonessential amino acid. And while there's been a lot of publications on taurine and what it does, there's no real consensus at these high doses on -- if and how it affects any type of mental or physical performance. And then there's some various vitamins, high levels of vitamin B and things like that often in these drinks as well.

NNAMDI800-433-8850. If you've ever had an adverse reaction to an energy drink, tell us what happened. You can also send email to kojo@wamu.org or send us a Tweet at kojoshow or simply go to our website kojoshow.org and join the conversation there. Barry, caffeine is in all kinds of cola type sodas but for some reason they seem to be regulated differently than energy drinks. Why is that?

MEIERWell, basically the cola producers struck a deal with the federal government a number of years ago where they would limit the quantities of caffeine in those particular beverages. Because these energy drinks are marketed as non-cola products or as dietary supplements, they're essentially free to put as much caffeine as they want into a product and also not even list it on the container.

MEIERJust in passing, I'm a great fan of caffeine. I mean, most adults need, use caffeine on a regular basis...

NNAMDIEspecially if they happen to be reporters, but go ahead.

MEIERExactly, or radio personalities. But you know, Dr. Shapiro might be able to address the more fundamental question, and that is where young people, teenagers, adolescents are concerned, you know, what are high levels of caffeine doing to them? And particularly when they're chugging a couple of cans of these beverages to be part of a party or a scene or whatever they want to be.

NNAMDIDr. Shapiro.

SHAPIROYeah, it's a very good question, Barry. There's no direct answer to it unfortunately. So the more you use caffeine, and we've all experienced this, the more you develop a tolerance to it. So what ends up happening is these adenosine receptors that are occupied by the caffeine up regulate overtime. And you're going to need more and more caffeine to fill those -- block those receptors and achieve the same effect of alertness that we get from our morning cup of coffee. And you can see people who build their habits overtime.

SHAPIROBut in terms of how much is too much, it varies. There is caffeine toxicity that can occur at relatively low doses of maybe 3 or 400 milligrams in people of low body weight who are naïve to caffeine. However, to product a lethal dose of caffeine toxicity you're looking at 13, 15 grams of caffeine, which is maybe 80 or 90 cups of coffee worth. So it depends on the individual. It depends on the weight of the individual. It depends on the usage of caffeine. And so there is not a particular level of caffeine ingestion that's going to equate to a specific physical outcome.

NNAMDIIt raises another question. Have you tried to curb the amount of caffeine you or your kids take in? Give us a call, 800-433-8850. We're talking with Scott Shapiro. He's a medical doctor. He's a director of Cardiac Arrhythmia Services at George Washington University Hospital, and a professor of medicine at the George Washington University School of Medicine and Health Sciences. Barry Meier is a reporter for the New York Times where he covers issues related to business, public health and the law.

NNAMDIBarry, you mentioned earlier about the ages of people who are using these energy drinks. These drinks are primarily marketed toward a very specific group. Who is drinking them and how do we see that push reflected in the ads and the outreach, the marketing campaigns?

MEIERWell, they're being promoted very heavily to adolescents and to people of college age. But to adolescents they're being promoted on YouTube, on Facebook. There are Tweeter feeds coming. These companies will take vans out to public parks where kids are skateboarding and hand out products there. So there's a very directed effort by a number of these producers to market these beverages to 13, 14, 15-year-olds. And to get them accustomed to drinking them, to build up the type of caffeine-related tolerance that Dr. Shapiro is talking about so that their body becomes adapted to wanting these types of products.

NNAMDIBarry, sales of these drink have gone up a lot in the last few years. Just how big a business is this?

MEIERAt last count it's about $10 billion a year and it's grown into a $10 billion a year industry within a decade, which is a fairly remarkable growth. So it's a big boom area. It's really a part of the beverage industry where there's been a generational shift, so kids instead of going into a convenience store and grabbing a coke or something like that will grab an energy drink. So it's very much a change in types of beverages that young people are drinking.

NNAMDIAnd because of the way they are regulated the manufacturers do not have to list all of the ingredients in these energy drinks?

MEIERYes, although I would only take exception because of the use of the phrase because of the way they are regulated. Effectively these beverages are not regulated. They -- or they are sold under regulations that do not require them to disclose much about the ingredients, including the levels of caffeine within them.

NNAMDIScott Shapiro, your average patient probably doesn't overlap a whole lot with the target audience that Barry described for these energy drinks. But I'm wondering if you do get questions from patients about safe consumption and what you tell them.

SHAPIROWell, Kojo, actually I have a broad range of patients. I deal with patients who have arrhythmias which are abnormal heart rhythms and that can happen in any age group. And caffeine is a common trigger in these patients who have a substrate for arrhythmia in terms of triggering or setting off their arrhythmia. And they learn themselves -- they're coming to me for help so they learn themselves to avoid these types of substances, coffee, energy drinks, chocolate sometimes to avoid going into their dangerous arrhythmias.

SHAPIRONow unfortunately young people may have the substrate for arrhythmia but it hasn't presented yet. And all of a sudden they may get a huge bolus of an energy drink or caffeine from an energy drink and this could be the initial presentation.

NNAMDIOnto the telephones. Here is Tom in Springfield, Va. Tom, you're on the air. Go ahead, please.

TOMThanks, Kojo. I have a couple of questions. One is do a lot of these drinks have extraordinary amounts of sugar in them, and two is there -- are there special concerns about kids using these with high doses of alcohol?

NNAMDIFirst and foremost, Barry, talk a little bit about what the drinks are that kids use with alcohol -- or what alcoholic beverages do kids use energy drinks with?

MEIERMainly vodka I think. I mean, that's sort of the traditional drink that you see around is Red Bull and vodka. Other energy drinks can be mixed with vodka. In fact, the energy drink producers will have like reps on college campuses whom they will supply with energy drinks, and while they will say if you ask them that, oh, well, we don't promote the use of these drinks with alcohol, these reps will go to fraternity/sorority parties where alcohol is being served with, you know, free boxes of energy drinks so these drinks can be mixed together.

MEIERIt's not clear as to whether there is like a direct connection with excessive drinking and energy drink use, but they are very, very popular mixers. In terms of the sugar levels, most of these products have very, very high sugar levels in them. So if you're concerned about your kids' sugar intake, that would be another area of concern.

NNAMDIDr. Shapiro, what is the danger of mixing these beverages with alcohol?

SCOTT SHAPIROAbsolutely. So you have alcohol which is a downer, and can make you tired, can make you confused, can slur your speech, and then you have this stimulant filled with tons of caffeine that can mask a lot of those symptoms. So where this becomes a particular issue is, it can fool an individual into thinking they are more sober than they are, perhaps drive a car that otherwise they didn't think they can drive. So it can alter their judgment in a way that they can believe that they're not as drunk as they think they might be.

NNAMDIGotta take a short break. If you have called, stay on the line. When we come back, we will get to your calls. We're talking about energy drinks, their rise in popularity, and what we do and do not know about them. You can call us at 800-433-8850 or sent us a tweet @kojoshow. Do you think energy drinks should be regulated by the government, or that their labels should contain more information? Why or why not? 800-433-8850. I'm Kojo Nnamdi.

NNAMDIWelcome back to our conversation on energy drinks. We're talking with Dr. Scott Shapiro. He's the director of cardiac arrhythmia services at George Washington University Hospital, and an assistant professor of medicine at the George Washington University School of Medicine and Health Sciences. Barry Meier is a reporter for the New York Times where he covers issues related to business, public health and the law.

NNAMDIBarry, a recent report found that ER visits in which these drinks are a factor have spiked in recent years. Just what kind of health issues are emergency rooms seeing in these visits, and how big of a rise are we talking about?

MEIERWell, Dr. Shapiro might know the specifics of that better than I do, but we're seeing a rise that is sort of commensurate with the rise in the consumption of these beverages. As they're going up, so are emergency room visits, and I think most of them tend to be people who are having heart arrhythmias, you know, rapid beating of their heart, sort of kind of a frightening high rate of heart beat that's being brought on by excessive caffeine consumption.

NNAMDIWe got an email from Megan who says, "I live in D.C. now, and sometimes I drive back to my home state of Kansas. On a recent trip back, I did not have a lot of sleep and had one of those well-known energy shots. Less than an hour after one of these shots, I had a major panic attack. I'm prone to panic attacks in general, but this was completely unexpected. I do not drink these anymore, and have begun to reduce my caffeine intake." Just what you would expect, Dr. Shapiro?

SHAPIROAbsolutely. You could -- very common to hear a complaint like this, and it's unclear whether what she experienced was a panic attack, whether it was arrhythmia or the heart racing was secondary to one or the other, but the energy drink or the caffeine bolus could certainly prompt either or.

NNAMDIHere's another response from Erika. "I tried 5-Hour Energy when I was a freshman in college and was terrified when my arms turned bright red and bumpy shortly thereafter. I read the fine print on the label, and it turns out this is not an uncommon reaction. I didn't try it again until just recently, six years later, and though I've never had the same side effect, it's always in the back of my mind. Now when I drink any kind of energy drink, which is not often, maybe twice a month, clearly there are some suspect ingredients in these beverages." Can you tell us anything at all about that, Barry, suspect ingredients?

MEIERWell, I don't know how to define suspect, but there's certainly many ingredients that are not doing consumers any good. That's not to say they're doing them bad, but, you know, the proof is in the pudding. The energy drink manufacturers have yet to put out a single study showing that any of these ingredients, in combination, or by themselves, provide consumers any benefits other than the benefit that they get from caffeine, along with the risks associated with excessive caffeine consumption.

MEIERSo I guess the question might be rephrased to be simply this: If energy drink manufacturers believe that these various ingredients, these suspect ingredients, whatever you want to call them, provide benefits, then perhaps they want to provide consumers with the data to support whatever claims they want to make.

NNAMDIWe got a statement from the American Beverage Association that goes as follows. "In the recent flurry of discussion about energy drinks, three important facts seem to have been last. First, despite wide-spread misperception, most mainstream energy drinks contain only about half the caffeine of a similar cup of coffee house coffee. Second, energy drinks, their ingredients and labeling are regulated by the U.S. Food and Drug Administration regardless of whether they are sold as conventional food or beverage or a dietary supplement, and third, as with all consumer products, energy drink marketing is subject to oversight from the Federal Trade Commission.

NNAMDI"Equally important, the members of the American Beverage Associated that manufacture energy drinks recognized the important role they play in continuing to educate the public about the safety of energy drinks and their ingredients. The American Beverage Association has adopted and encourages all energy drink companies to adopt a guidance for the responsible labeling and marketing of energy drinks under which companies voluntarily display caffeine amounts on their packages along with an advisory statement that the product is not intended or recommend for children, pregnant or nursing women, and persons sensitive to caffeine."

NNAMDIYou may have seen something similar as you were preparing your story, Barry Meier.

MEIERYes. And as you know, the American Beverage Association is a lobbying organization that represents major producers. Many of those same companies belong to the Canadian Beverage Association, and in Canada the Canadian Beverage Association supports a limit of a hundred -- 180 milligrams of caffeine per can of energy drink. So I would ask the American Beverage Association if you bump into them at any Washington functions why they don't support similar limits here in the United States.

NNAMDIOnto the telephones again. Here is Erik in Washington D.C. Erik, you're on the air. Go ahead, please.

ERIKThank you, Kojo. I'm calling because I work in D.C., and I work in a nightclub and I'm a bartender. And some of the other bartenders and I, during our extended hours, which is usually about 4:00 in the afternoon until 2:00 in the morning, drink lots of the Red Bull energy drink to keep going, because we usually don't take any breaks because it's such a busy club.

ERIKSo I was just curious if energy drinks are duping our bodies into making us able to do extended amounts of work that might otherwise be harmful if we hadn't been taking them.

NNAMDIOr if you are taking them. Here is Dr. Shapiro.

SHAPIROWell, this has been looked at actually in the training of medical residents and the issue of sleep deprivation. So medical residents, during their training, often work very long hours, and studies have been done on those residents to see if caffeine improved their performance. And just like you, experience with your ability to perform long hours in the nightclub, sure enough, caffeine can promote alertness and improve performance in people who are sleep deprived.

SHAPIROHowever, it does not replace the quality of the performance that would be done if you had actually slept. So yes, caffeine can mask some of the symptoms of fatigue, absolutely. Over a long period of time though, you're going to build up some resistance to the amount of Red Bull, and you're going to need more and more to do the deed that you're trying to achieve.

NNAMDIThank you very much for your call, Erik. But Erik, you might want to keep listening because here now is Farhad in Greenbelt, Md., who may have something to say about this. Farhad, you're on the air. Go ahead, please.

FARHADHi Kojo. I'm a physician in Greenbelt, Md. also, and thank you for the other doctors that they are doing the discussion. I've noticed a lot of my patients that have sleep apnea, they need a lot of caffeine, and they usually take caffeine and nicotine and getting in the habit of smoking again, and also they use alcohol to get a deeper sleep. And I believe most of these patients originally have sleep apnea and they needed to have stimulants such as caffeine and nicotine to get -- to be awake and do their life, but I just wonder if it was -- whether it was the egg first or the chicken -- or the chicken or egg first, or which one is the case. Thank you.

NNAMDIWhat do you say to that, Scott Shapiro, the chicken or the egg?

SHAPIRONo. Sleep apnea produced daytime (word?), absolutely, and caffeine can at least in part overcome some of those symptoms. I think obviously the best way to do that is to treat the sleep apnea, and you can avoid some of the consequences. But you're right, you could get yourself into a little bit of a cycle there. And I think the doctor brings up a good point because we talk about the targeting of young people by these energy drink companies, but older people as well use these energy drinks to function in their normal life, and these are people who are more prone to the cardiac effects of caffeine, and so we have to be particularly concerned about people who have heart disease, coronary disease, structural heart disease, and in the use of large doses of caffeine which could potentially trigger dangerous arrhythmias.

NNAMDISpeaking of which, Barry Meier, the report on ER visits came shortly after the FDA disclosed a series of reports linking energy drinks to both injury reports and a number of deaths. What exactly do and don't these reports tell us about the safety of these products?

MEIERYou know, the reports themselves are not conclusive definitive. They're just reports. They're just accounts from the emergency rooms, consumers, lawyers, whomever, of an injury or death where they believe an energy drink may have played a role. So they have to be taken with a grain of salt. They're also very few in number because there's not a requirement for all producers to make these reports to the government. All producers do not necessarily make such reports to the government even if required.

MEIERI think a much better indicator is this emergency room data that you referred to before, because there you have a very steady stream of reports coming in showing that the types of reactions that some of your callers have -- or correspondents have noted, you know, panic attacks, increased heartbeat, the type of flush that the one woman was discussing, are fairly common. I mean, they're not that unusual. They happen on a fairly regular basis in connection with the consumption of these beverages.

NNAMDIWell, some claims that the companies make in ads have been challenged by watchdog groups, and at least one Congressman wants the Federal Trade Commission to look into the matter. What are some of the concerns that have been voice, Barry?

MEIERThe basic concerns that have been voiced is that companies are making claims that may not have basis in fact. For example, 5-hour energy claims that there's no crash, you know, crash meaning that you drink a cup of coffee in the morning, four or five hours later you're feeling groggy, you're having a crash, you need more caffeine to kind of get that boost again. They ran a test where they found that one out of every four people drinking 5-hour energy had a crash, but rather than saying that, they claim on their product that there's quote -- they have a little indicia mark where it leads you down to the fine print, and it claims no sugar crash.

MEIERWell, that's not a hard claim to make because 5-hour energy does not contain any sugar, and they were told by an advertising bureau not to make that claim, not to make a no-crash claim. They went ahead and made it. Now that advertising bureau is looking into that claim and may refer it to the Federal Trade Commission. Those are the types of claims

NNAMDIHere is Scott in Silver Spring, Md., who can tell us about his personal experience. Scott, go ahead, please.

SCOTTHi, Kojo. I just wanted to say that I've used 5-hour Energy for about four years. I'm a student at University of Maryland, and I have had amazing results. I find that I get a consistent level of energy from them. It's very predictable, I don't have a lot of variation after each use. So it just seems to me that a lot of the variability in people's experiences might depend more on individual health or their own bodies rather than the product being dangerous in themselves.

NNAMDIDr. Shapiro?

SHAPIROScott, I don't know how much you're using these drinks, but certainly I think the majority of people will not have a problem -- a major problem with the caffeine intake. Certainly if you're using it on a once-in-a-while basis, and you're not building up a tolerance to it, you're going to experience alertness and perhaps a better performance with studying or whatever your activity is if you take it on occasion.

SHAPIROBut I think the concern is the lack of disclosure of the ingredients, and people who may be more susceptible to dangerous outcomes.

NNAMDIBarry, several attorneys, general and county Boards of Health, have started to look at what they can do to regulate sales on a local level, and a trio of members of Congress recently wrote directly to over a dozen companies that make these drinks asking for them to disclose a laundry list of information. Is stricter regulation on the horizon you think?

MEIERI don't know whether it is. I don't know whether it's necessary. You know, I think an informed public, a public that is told what is in these drinks, how valid these marketing claims are, the caller that called in made a very good point. He uses energy drinks and he gets what he wants out of them, and as Dr. Shapiro mentioned, there are many people that are going to use these drinks and get what they want out of them. They might get the same thing out of a cup of coffee, or I have a cappuccino in the morning.

MEIERI get a lot out of it. I really enjoy it. And so if people use these drinks, they function for them, they work for them, that's fine. There are others who they might not work for, and those people need to know just what's in the drink and what these drinks actually do.

NNAMDIBarry Meier is a reporter for the New York Times where he covers issues related to business, public health and the law. Barry, thank you for joining us.

MEIERThanks so much for having me on.

NNAMDIDr. Scott Shapiro is the director of cardiac arrhythmia services at George Washington University Hospital, and a professor of medicine at the George Washington University School of Medicine and Health Sciences. Dr. Shapiro, thank you for joining us.

SHAPIROThank you, Kojo, and thank you, Barry, for participating.

NNAMDI"The Kojo Nnamdi Show" is produced by Brendan Sweeney, Michael Martinez, Ingalisa Schrobsdorff, Tayla Burney, Kathy Goldgeier, and Elizabeth Weinstein with help from Stephannie Stokes. The engineer is Tobey Schreiner, the all-day miner. Natalie Yuravlivker is on the phones. Thank you all for listening. I'm Kojo Nnamdi.