Do Energy Drinks Really Work?
Move over, baristas! There's a new supercharged sip in town that's giving your local Starbucks some stiff competition. A host of energy drinks, shots, and gels are flooding the marketplace, promising to get you through your afternoon meeting, yes, but that's just the beginning. Today's energy products also claim to boost your workout, improve your health, and help you stay more alert. It's no surprise that business is booming: Around the world in 2010, energy-starved people downed close to 4 billion cans of Red Bull Energy Drink, a brand barely known in this country just 10 years ago. In the United States alone, the market value of energy drinks hit $4.9 billion last year, according to the Mintel International Group, a market research firm. What's more, between 2002 and 2007, total retail sales of energy drinks increased a reported 440 percent, to an estimated $6.6 billion.
Research forecasts that by 2014, sports and energy drinks' global market value may reach $47 billion, according to Just-drinks.com, a compiler of beverage industry information. But for all the hype, do these moolah-making java stand-ins really give you wings? How does the "energy" in one of these products compare with, say, the energy you get from a homemade PB&J? What really works to power you through your run or a meeting with your boss? FITNESS investigates.
What's Really in an Energy Drink?
Known for their fast-acting jolt, energy drinks like Red Bull and Monster tout a high dose of caffeine and a varying blend of "energizing" extras that include vitamins and amino acids and herbal supplements. But despite the eye-catching cans and slick marketing, the main ingredient responsible for that mojo is good old-fashioned sugar. "Calories are energy, plain and simple," says Katherine Zeratsky, RD, a dietitian at the Mayo Clinic in Rochester, Minnesota. "It's what your body uses for fuel. Any food, whether it's a turkey sandwich, a can of soda, or an apple, has energy. Energy drinks should be thought of as calorie drinks."
They can pack a lot of them, too: A 16-ounce can of Red Bull Energy Drink has 220 calories, and a 24-ounce can of Rockstar Energy Drink has a whopping 420, almost as much as a double cheeseburger. Unlike most foods, however, most of the calories in energy beverages come from simple sugars. Devoid of fiber, fat, and protein, three nutrients that slow digestion, the sugar hits the bloodstream quickly, giving you the superfast rush you crave. Sadly, it's short-lived. "Your body wants only so much sugar in the blood at a time," Zeratsky says. "When it receives a big load, the pancreas shoots out any additional insulin to push sugar it doesn't currently need into fat cells." In the long run, having too many energy drinks, like consuming too much soda, can cause weight gain. In the short term, you are faced with the infamous energy-drink crash. Either way, you're left tired and still looking for a lift.
Hoping to skip the sugar and save calories, some women opt for the sugar-free versions of their favorite energy drinks, relying on the high caffeine content to give them a boost. "Caffeine is widely studied and well-known for making you feel more alert," says Matthew Ganio, PhD, a researcher at the Institute for Exercise and Environmental Medicine at Texas Health Presbyterian Hospital in Dallas. "But its effects come from being a stimulant, meaning it makes you feel energetic by offsetting the mental and physical fatigue that occurs throughout the day, especially during exercise." Currently, the FDA doesn't limit the amount of caffeine in energy drinks, so manufacturers often pack from 50 to 200-plus milligrams into a 16-ounce serving (the average cup of coffee contains anywhere from 40 to 180 milligrams). Check the label, however, because some drinks go way beyond that range: A 16-ounce can of Wired X 344, for instance, has 344 milligrams. "More isn't always better with caffeine," says John Higgins, MD, director of exercise physiology at Memorial Hermann Sports Medicine Institute in Houston. In some people, more than 200 milligrams can cause insomnia, nervousness, headache, and nausea.
As for the effectiveness of the brand-specific blend of supplements and amino acids, it's debatable. "These ingredients are mainly about smart marketing," says Kevin Clauson, associate professor at Nova Southeastern University College of Pharmacy in Fort Lauderdale, Florida. "Some have studies backing the beneficial claims, but most of these ingredients are in quantities far below the amounts needed for any actual benefit." If you'd prefer a low-tech boost, go for a glass of milk, a cup of yogurt with fruit, or an apple with a little peanut butter. The mix of carbohydrate, protein, and fat will ultimately slow digestion, thus preventing the spike and subsequent roller-coaster drop in blood sugar. "Your energy will last longer, and you'll get a nice dose of nutrients along with the calories," Zeratsky says.
Energy Shots, Sports Drinks, and Power Packs
For a lower-calorie, less filling alternative to energy drinks, consumers are turning to energy shots, the fastest-growing category in the energy-beverage market. Sales jumped from $67 million in 2008 to $165 million in 2010, according to Mintel. Marketers at Red Bull say that the size of the company's Energy Shot is a plus for consumers, who can stick it in a purse or back pocket. "Distance runners or cyclists might be tempted to use energy shots as a quick, portable fix," says Nancy Clark, RD, author of Nancy Clark's Sports Nutrition Guidebook. Toss back a two-ounce bottle shot, such as 5-Hour Energy, and you'll get roughly the same amount of caffeine, vitamins, and supplements that are in the average energy drink, minus the calories and pick-me-up from sugar. "An energy shot is sort of a misnomer, because there is no energy, calorically speaking, in it," Clark says. "It's really a stimulant drink."
But your body gradually develops a tolerance to caffeine's effect, and you become desensitized to its buzz. "If you've ever noticed how one cup of coffee used to get you going in the morning, and now it takes two or three, it's the same thing with energy shots," Ganio says. "The body builds a resistance to caffeine over time, requiring you to consume more and more to get that same lift."
One of caffeine's secrets is that it doesn't just stimulate your brain; it keeps it from detecting fatigue. "Every function of the body requires the molecule ATP, adenosine-5-triphosphate, to work," Ganio explains. "As the ATP is used and broken down, it creates the by-product adenosine. Adenosine binds to receptors in the brain, resulting in feelings of lethargy. Caffeine binds to these same receptors, however, blocking the adenosine from attaching, so you're left feeling awake."
Sports drinks, such as Gatorade and Powerade, were designed primarily for two reasons: to help athletes stay hydrated and to provide them with energy. "When the availability of carbohydrates gets too low, the body starts converting fat stores or, in extreme conditions, amino acids from the muscles into energy," says Melissa Tippet, an exercise scientist at the Gatorade Sports Science Institute in Barrington, Illinois. "However, this process is too slow to support intense exercise." Enter sports drinks, which provide easy access to carbs.
Designed specifically to be used during physical activity, sports drinks tend to have less sugar than energy drinks. "On average an energy drink can have upward of 100 calories per eight-ounce serving; a sports drink has 50 to 80," Clark says. Whether you need the fuel a sports drink provides depends on how hard and long you're working out. "If you've eaten prior to exercising, you won't need additional carbs until you've been working out for 60 to 90 minutes," Clark says. "But if you work out first thing in the morning, sipping a sports beverage will raise blood sugar levels and give you more energy to get through it."
Because sports drinks are typically formulated with a more diverse blend of carbs than energy drinks are, your muscles can maximize their energy-sustaining potential. "Each type of sugar, whether it's fructose, sucrose, or glucose, has specific transporters in the body that move it between the intestines, blood, and muscle," Tippet says. "If you have too much of one type of sugar at a time, it can max out its transporter and just sit in the stomach or intestines."
Wondering about the new, low-cal options? Although Gatorade's new G Series Fit 02 Perform and others replace fluids and electrolytes, they don't give the body much fuel, because the sugars have been replaced with substitutes. If the flavors of the lab-created beverages don't do it for you, you can make your own sports drinks by diluting fruit juice with water in equal parts, Clark advises.
Commonly ranging from 90 to 120 calories a serving, energy gels and gummies promise to prep the body for exercise and help you work out longer. "They are like dehydrated sports drinks," Clark says, noting that you should drink 16 ounces of water with every 100-calorie gel to ensure that you stay hydrated. "We recommend that people doing an endurance sport, like running or biking, consume a gel 15 minutes before exercise and every 45 minutes for the duration of the workout," says Brent Mann, director of quality for Gu Energy Labs in Berkeley, California. "Taking in carbohydrates at these intervals prevents your body from dipping into its glycogen stores, its last resort for energy." (Most experts stress that products such as Gu Energy Gel and PowerBar Energy Gel are geared to endurance sports, much as sports drinks are; the average exerciser doesn't need additional calories if she's eaten within 90 minutes of a treadmill session.)
In addition to sugar, most energy gels contain small amounts of sodium and potassium to help replenish electrolytes; some also contain caffeine. "Caffeine has been shown to lower perceived exertion during exercise and lessen muscle pain," Ganio says. "The debate is this: Studies show you need a lot — six milligrams of caffeine for every 2.2 pounds of body weight — to achieve this effect." That means that a 140-pound woman would need 381.8 milligrams of the stimulant, roughly four cups of coffee. So while some gels in the Gu line contain up to 35 milligrams of caffeine, Gatorade's G Series 01 Prime liquid formula contains none. "Caffeine isn't in any of our products," Tippet says. "Everyone responds differently to caffeine; it's effective for some people but for others may cause negative side effects, like jitteriness and heart palpitations."
One perk of these products, some industry experts say, is that they require little work from your stomach. "During intense exercise, blood that is normally in your gut to aid in digestion is redirected to the heart and working muscles," so you want something that goes down easy, Mann says. "That's where these gels can help."
So which of these engine revvers is really right for you? In moderation, any of them should give you the lift you're looking for without dangerous side effects. The bottom line, experts say, is to first make sure your diet offers the nutrients your body needs. "If they're eating the right foods, many women may not feel it's necessary to supplement at all," Zeratsky says. The best energy, it turns out, comes straight from nature.
Do the Ingredients in Your Energy Drink Work?
The real scoop on whether the vitamins, minerals, and dietary supplements in your energy drink really work:
Claim: Improves alertness and physical performance; reduces fatigue
The science: "Caffeine is a component of guarana, which is why it can provide similar benefits," says Kevin Clauson of Nova Southeastern University College of Pharmacy in Fort Lauderdale, Florida. But since the amount of caffeine varies from 2 to 8 percent, it's hard to determine exactly how big a boost you'll get.
Ingredient: B vitamins
Claim: Boost energy and metabolism
The science: "B vitamins help convert food into energy," says Nancy Clark, RD. "However, only a person who is B deficient will get any benefit, and it would take regular supplementation." And studies to date have reported that B vitamins have no effect on performance, a 2010 review in the journal Physician and Sportsmedicine found.
Claim: Lessens exercise-induced DNA damage, thereby improving exercise capacity and performance
The science: Few scientifically accepted studies confirm taurine's performance enhancing powers.
Claim: Increases stamina, energy, and mental focus
The science: "There are many types of ginseng, and from what the literature shows, only Panax provides the full range of these benefits," Clauson says. "You need anywhere from 100 to 2,000 milligrams per day to see any real benefits." Most energy drinks contain much less.
How to Eat for Energy
"If you're taking an energy supplement, it may be because good nutrition or adequate sleep is lacking," says Katherine Zeratsky, RD, a dietitian at the Mayo Clinic in Rochester, Minnesota. Take a look at your overall eating habits. "The first step to all-day energy is to make sure you're not skipping meals," Zeratsky says. "A lot of women curb calorie intake in the morning and afternoon, which leads to energy slumps followed by nighttime bingeing." Aim for 400 to 500 calories at each meal, and at intervals throughout the day, have three 100- to 200-calorie snacks that combine fiber-rich carbs, like fruit, vegetables, and whole grains; lean proteins, like grilled chicken, turkey, and fish; and healthy sources of fat, like walnuts and olive oil. This mix slows digestion and helps keep energy levels stable.
Originally published in FITNESS magazine, April 2011.