What are energy drinks really doing to you?

JAY SASSINE SMACKED his lips together. He’d just drunk his fourth or fifth Red Bull of the day and the sweet, yellowy fluid was starting to taste a little bit weird. “It was just bland and a bit sticky,” recalls Sassine, a 26-year-old auto compliance agent from Sydney. “Like when you eat a lolly and can’t get it off the roof of your mouth.” He didn’t know it yet but the ickyness was a taste of things to come.

It was 2009 and Sassine and his boss were seriously up against it. A run-out sale on Subaru WRXs meant they were pulling 13-hour days, fitting compliance plates, installing accessories, cleaning, vacuuming and “data-dotting” parts in case of robbery. Where normally they’d do 10 vehicles a day, now they were fitting out up to 40. Leaden limbed and bone weary, Red Bull, they reasoned, would give them wings.

“We hit them pretty hard,” remembers Sassine. “In a week we did a case, easy. Then we ordered another case from the café.” In total he estimates they downed around eight cans a day for three weeks.

At first the drinks had a positive effect. “They were giving me the energy I needed,” says Sassine. But after the second week, events began to resemble a B-grade horror movie. “I started getting cramps in the middle of the night where I’d wake up screaming,” he recalls. Scary stuff, but nothing compared to what happened next.

Towards the end of the third week Sassine was driving home with his girlfriend when he noticed the car in front of him swaying all over the road. “I looked over at my girlfriend as if to say, ‘look at this idiot’ and she was swaying too,” he says. “I was like, ‘oh crap’. She was yelling, ‘what the hell are you doing? You’re moving all over the road’.” At that moment Sassine’s face began to break out in pins and needles. He pulled over and within seconds everything went black. “I was shitting myself,” he says. “I sat there opening and closing my eyes while my girlfriend was pouring water over my face.” After 15 terrifying minutes his vision returned.

It’s likely that Sassine was having a seizure resulting from a caffeine overdose. But who really knows? The trouble with energy drinks, a section of the beverage market reportedly worth around $550 million a year, is that you can never be entirely sure what effect they’ll have on your body. But that doesn’t stop blokes tipping them down their throat like they were, well, Coca Cola. Sure, most manufacturers slap a warning on the can that advises against consuming more than two a day. But at the same time, their marketing and branding encourages, even glorifies, excess. How many people heed the warning? Among sections of the target market of young men, probably about as many who follow Government guidelines to drink no more than four alcoholic drinks a day.

“The thing with energy drinks is that people use them to replace coffee and it becomes a regular thing, where they consume them a couple of times a week in very large amounts,” says Dr Conrad Woolsey, an assistant professor of health and human performance at Oklahoma State University.

Related: What else is in your energy drink?

The result is that scary ordeals like the one Sassine experienced are on the rise. A report published earlier this year in the Medical Journal of Australia found calls to the NSW Poisons Centre regarding adverse reactions to energy drinks – heart problems, tremors, seizures and chest pains – increased by over 400 per cent between 2004 and 2010, with more than a third of people attending hospital. Not surprisingly, the majority of those amped-up patients were men.

Energy drink manufacturers have you in their sights. Products are aggressively marketed around hyper-masculine characteristics, emphasising vigour, power and an all-round hardcore approach to life that finds its natural conclusion on sporting fields, gyms, music festivals and nightclubs – all areas that encourage excess and require energy. Lots of it.

“The name of the brand, the advertising, the marketing – all of that encourages any pre-existing attitude toward novelty seeking, risk-taking and sensation-seeking,” says Kathleen Miller, senior research scientist at the Research Institute on Addictions at the University of Buffalo. She adds the trading floor to the roll call of male-dominated domains that run on adrenaline with a drip-feed to a can.

“Back in the Eighties bond traders used cocaine to stay awake,” says Miller, who’s studied energy drink use among various sub-cultures, including college athletes and musicians. “Today they use Red Bull.”

The trouble is, whether you’re a hero of the track, a monster of the mosh pit or a titan of the trading floor, there may be a price to pay for all that pep. You may not end up in a blind panic on the side of the road like Sassine. But in the long run there’s a good chance you could wind up just as tired as when you first reached for that can.

Hawthorn Football Club superstar Lance “Buddy” Franklin recently appeared in an advertisement for new Powerade product, Fuel Plus. Not to be confused with the company’s hydration products, the beverage is an energy drink that contains caffeine and comes with that “two can per day” warning. Associations with elite and extreme sports fulfill two functions for energy drink manufacturers. Firstly, like any form of advertising, they underscore an aspirational promise.

Secondly, they foster a perception that the drinks are performance enhancing. That, along with aggressive marketing and a strong presence at sporting events and gyms distils a clear message: fuelling your workout, snowboarding session or game of footy with liquid energy can help you react quicker, pump harder, be more hardcore for longer. But the question is, when you cough up for your can, are you getting bang for your buck?

Energy drinks’ primary functional ingredient, caffeine, is one of the most easily absorbed of all chemical compounds. From your throat it quickly enters your bloodstream, dilating your blood vessels, before moving into your brain where it blocks the functioning of your adenosine receptors. This serves to unleash neurotransmitters involved in arousal and alertness, such as dopamine and serotonin, along with stress hormones like nor-adrenaline and adrenaline. The drug has been clinically proven to give you a boost, particularly if you’re already fatigued.

Related: The downside of your morning coffee

Most energy drinks range from 80 to 200 milligrams of caffeine per can – enough to have a marked effect, says Professor Andrew Scholey, director of the Centre for Human Psychopharmacology at Melbourne’s Swinburne University. But it does depend on what you regard as an effect, he says. “There’s currently a serious debate in academic circles as to whether caffeine actually improves mental function or whether in most consumers it just alleviates withdrawal symptoms,” he says. “It’s not at all clear.”

But whether the effect is induced by prior caffeine consumption or not, a number of studies measuring individual variables, such as reaction time or output, indicate that energy drinks do appear to have a positive impact on performance. A study at Northern Kentucky University measuring cued response time and levels of mental fatigue after drinking Red Bull returned positive results in both variables, although the optimal effect appeared to be dependent on the dose: participants on the lowest dose of the drink actually had the best response time.

But there are a couple of problems with studies like these, according to Woolsey, a former college shot put star who, since moving into academia, has closely monitored energy drink use among athletes. Quite often the studies are funded by manufacturers, he says. Secondly, most sports involve complex movements that rely on multiple variables. In these cases there’s a good chance an energy drink will do more harm than good.

To investigate, Woolsey conducted a study on student airline pilots, a profession that hinges on complex mental processing. Those who downed a 500-millilitre energy drink 30 minutes before take-off had a harder time maintaining straight and level flight, and were 10 seconds slower to return their plane to the proper position after executing a complex turn, than those drinking a placebo. So what’s going on? The caffeine, taurine, sugar and other stimulants make it difficult for your body to perform simultaneous tasks, says Woolsey, although the participants themselves didn’t know it. “The participants actually thought they were doing well, but made more mistakes because they were over stimulated,” he says. “There’s a part of your brain that coordinates and sequences movements. You can improve your reaction time but if you throw off the sequencing you’re not going to perform as well.”

Woolsey found similar results in another study on baseball players, many of whom load up on energy drinks in the hope that quicker reaction times will help them knock a fastball out of the park. “Energy drinks might give you faster reaction time but they actually mess with how your eyes dilate,” says Woolsey. “They don’t respond to light as they should.” The result, he found, was that players juiced on energy drinks actually swung at worse pitches.
What does this mean for you? Before a gym session, a single energy drink may give your training a focused buzz. Before a team sport, or anything that relies on complex coordinated movements, though, you could lose precision and dexterity. In other words, you’ll be like a gorilla with a paintbrush in your hand.

Sydney cardiologist Professor Chris Semsarian tells a good fright story, even if it’s one you’ve probably heard before. “A young bloke drops dead from a heart attack during a half-marathon,” says Semsarian, as we chat in his office at the Centenary Institute at Royal Prince Alfred Hospital. “He had no previous incidence of heart problems, but it later emerges that he had an underlying condition, which for unknown reasons, was triggered by exercise.” Or in an increasing number of cases, reckons Semsarian, by an energy drink.

The professor should know. He’s treated five people who’ve overdosed on energy drinks in the past two years. “You can have a heart condition, not know about it, drink something like this and it can trigger that event,” he warns. The most common genetic condition, hypertrophic cardio myopathy, affects around one in 500 people and is the most common cause of death among athletes. By contrast, diseases considered fairly common, such as multiple sclerosis and cystic fibrosis, affect around one in 1000, says Semsarian.

Related: Cola's effect on your health

Energy drinks have two effects on the heart. They stimulate it, which speeds up the rhythm. Secondly they increase blood pressure. “Drinking an energy drink is a bit like doing a mild exercise test,” says Semsarian. “You can be playing sport and your heart rate goes up to 130, 140, then you put an energy drink on top of that. Anything that does that is a potential trigger for an abnormal rhythm. It’s almost the worst thing you can do.”

So what’s the difference between downing an energy drink and chugging large quantities of coffee, besides the enormous amounts of sugar you pump into your system (see box, Battle of the Buzz)? It’s a question the industry’s advocacy body, The Australian Beverages Council, has been asking a lot lately. “There’s no evidence that the 80mg of caffeine consumed through an energy drink is any different from the 80mg of caffeine consumed through a cup of coffee,” says the council’s CEO Geoff Parker, who adds that if caffeine over-consumption is a concern, labelling and sale provisions should be extended to coffee, tea and chocolate bars.

It’s a fair point, but there are important differences in the way the two beverages are consumed, Semsarian points out. “Coffee’s hot, so we drink it slowly,” he says. “These energy drinks are cold and they’re designed to be drunk fast. Coffee also doesn’t have taurine and guarana or all these other additives in it. They’re on another level.”
Guarana and taurine are just a two of a host of exotic ingredients you’ll find on the side of an energy drink can.

Inositol, glucuronolactone, ginko biloba, ginseng and various combinations of B vitamins are the others that pop up most frequently (see box, Energy or Enemy). It’s unlikely that any of these ingredients present a real danger when consumed in moderation. As Parker notes, a 2009 report by the European Food Safety Authority found no evidence that key ingredients in energy drinks, such as taurine and glucuronolactone, were of concern. The real question is, do they have a positive effect? Although clinical studies have found that some of these ingredients enhance cognition and stimulate brain activity in isolation, in concert the data is far less clear.

“Quite often the trials into the effects of these energy drinks don’t look at the whole product,” says Scholey. “A manufacturer might throw together guarana, ginseng and caffeine with the assumption that they will have a positive effect, but without having any data on that combination.”

It’s likely that in some cases the inclusion of these compounds is largely cosmetic. Manufacturers sometimes throw in herbal extracts, says Scholey, to capitalise on public awareness of what he calls “image ingredients”. The trouble is that in many cases the doses are often negligible. For ginko biloba the psychoactive dose is between 100-200mg, says Scholey. For ginseng it’s around 200-400mg. Given that some beverages on the market feature less than 100mg of these extracts, you’d be wise to check the label before you crack one open.

If you’ve ever knocked back a Jagerbomb – Jagermeister mixed with an energy drink – you’ll know it’s a drink as lethal as its name suggests. And chances are you didn’t stop at one. “Jagerbombs are marketed in a way that encourages binge drinking,” says Miller. “When you drink a Jagerbomb it’s a drink that has an act. You don’t sit down on a sofa at the end of an evening and quietly sip it.” If you’re looking at a long night at a club, a Jagerbomb or six is your go-to beverage for untapped energy and, potentially, wholesale debauchery. Particularly if you can’t get any drugs.

“People use energy drinks in a similar fashion to the way they use illicit stimulants in combination with alcohol,” says Amy Pennay, a research fellow at Turning Point Alcohol and Drug Centre in Melbourne, who completed a study on energy drinks and alcohol in bars and clubs last year. “They don’t get the same rush, but they use them to counteract the drowsy effects of alcohol.” Most people surveyed enjoyed themselves on energy drinks, says Pennay, citing perceptions of enhanced alertness and increased engagement with friends. “The drinks actually made them feel like they were having a better time,” she says. “They were suddenly more interested in conversations, they wanted to dance and they were able to stay out longer and have more fun.”

The assumption that energy drinks counter or heighten the effects of alcohol is a common one, says Scholey. It could also be a false and potentially dangerous one. “The stimulant effects of an energy drink don’t seem to counteract the sedative effects of alcohol,” he says. But if you believe they do it doesn’t matter, you’ll drink more. The result? Your “come down” is likely to be as brain jarring as the previous night was mind blowing. “When the alcohol wears off, the caffeine’s effects are quite unpleasant,” says Pennay. “People reported feeling like death the next day. They’re anxious, they’re agitated – typical overdose symptoms. They don’t even trace it back to the energy drinks.”

It doesn’t take a psychopharmacologist to understand that great highs are invariably followed by crashing lows. “You’ll see studies that say energy drinks enhance mood two hours after consumption,” says Woolsey. “If you asked the question after eight hours it would have worsened your mood.” The inescapable conclusion is that if you take a ride on the neurochemical rollercoaster you’re always going to have to get off at the bottom.

What awaits you when you get there? Nobody knows for sure what the long-term effects of prolonged energy drink use are, but like amphetamines, which also hammer neurotransmitter receptor sites, it could well be a real downer. “When you’re releasing more dopamine and serotonin than you need to, you’ll naturally become deficient,” warns Woolsey. “What I worry about is that it could predispose people to bi-polar or depression, because you’re literally going from being up to crashing and feeling low. You get to a point where you wake up and feel like crap unless you have one.”

And even if you don’t get to that point, you’ll probably end up exactly where you started: dead tired. “Sooner or later they quit working,” confirms Woolsey. “You no longer get the buzz.”

Sassine, who has rarely touched an energy drink since his adverse reaction can vouch for that. “I’ve had the odd can since and I don’t get anything from it,” he says. “I could be falling asleep and have an energy drink and I’ll still fall asleep just as quickly. It does nothing for me anymore.”