If you're one of those people who routinely burn the candle at both ends, you may find yourself running out of energy midway through the day. Yesterday's overachiever reached for a cup of coffee; today's overachiever might reach for an energy drink instead. Oh, by the way, today's overachiever in need of an energy boost is also more likely to be 12 to 24 years old.



Energy drinks are soft drinks advertised as providing energy to improve physical activity of the drinker, as compared to a typical drink. Rather than providing food energy, these drinks are designed to increase mental alertness and physical performance by the addition of caffeine, vitamins, and herbal supplements which may interact to provide a stimulant effect over and above any effect from just caffeine.

There is a second type of energy drink, more often referred to as a sports drink, that combines fluid/electrolyte replacement with either simple or complex carbohydrates (usually glucose or maltodextrose) to provide energy and hydration during strenuous physical exercise. These drinks are not included in this discussion.

Most energy drinks rely on caffeine or a combination of caffeine and sugar or a combination of caffeine, sugar and other supplements such as amino acids, vitamins and herbal extracts to create an energy boost.

Caffeine is almost always the primary ingredient in energy drinks. Once ingested, caffeine acts like adenosine, a biochemical with a number of specialized functions in the body. When adenosine binds to adenosine receptors in the nervous system, it inhibits nervous system activity, creating a calming, drowsy effect. Caffeine mimics adenosine, and binds to the adenosine receptors in your brain, preventing the real adenosine from slowing down nerve impulses so your brain becomes more alert. At the same time, the absence of bound adenosine results in a higher level of dopamine being released into the blood system. Dopamine improves feelings of well-being and enhances mood. It's this dopamine effect that is the root of caffeine's addictive properties.

Energy drinks vary widely in the amount of caffeine they contain. With drinks packing as much as 171 mg of caffeine per ounce, it's easy to ingest a lot of caffeine without knowing it.

The sugar found in most energy drinks is in a very simple form which can be quickly digested and transformed into a short-lived burst of energy. Sugar is an energy-only constituent, adding no proteins, minerals or other nutrition.

Taurine is an amino acid that is found in abundance in muscle tissue. While some studies have indicated that taurine, combined with caffeine, improves mental performance, those studies have generally been too small to draw definitive conclusions. On the other hand, Cornell researchers recently discovered a receptor for taurine in the brain, suggesting that taurine may have a role in neurological development and may actually contribute to the crash people often experience after the energy jolt from an energy drink.

Guarana is a berry that grows in Venezuela and Brazil. Its extract is used as a flavoring and as a caffeine-like stimulant. The few studies that exist suggest that guarana may have either no effect or a limited stimulant effect. Energy drinks add guanara as an additional source of nervous system stimulation.

Yerba mate is a type of holly native to South America. Leaves from this bush-like plant are steeped to access the chemically active ingredient mateine, which chemists do not distinguish from caffeine.

So what's the fuss? The controversy around energy drinks focuses on several issues including safety, especially effects of excessive caffeine, quality control and labeling issues, combination with alcohol and marketing that is targeted at tweens and teens.

Although a ubiquitous component of daily life, caffeine is not without risks. Most of us have at least some anecdotal evidence of the effects of too much caffeine, the heart racing jitters that accompany a few too many espressos. In fact, excessive caffeine intake can lead to not only a fast heart rate and tremors but also excessive urination, nausea, vomiting, restlessness, anxiety, depression and difficulty sleeping.

Many, many studies have done to determine whether caffeine is good for you or bad for you and frankly it's still not completely clear. However, both the American Medical Association (AMA) and The National Institutes on Health (NIH) indicate that moderate caffeine intake is not associated with any health risk. So what's moderate and what's excessive? Again, according to NIH, a moderate amount of caffeine consumption is 250 mg per day (2-3 8 oz. cups of coffee). Excessive intake is identified as ten cups of coffee per day.

There is not the same uncertainty about the issue of caffeine in children. NIH says that "A child's caffeine consumption should be closely monitored". Although caffeine is safe to consume in moderation, it may negatively affect a child's nutrition. Caffeinated beverages may be replacing nutrient-dense foods such as milk. A child may also eat less because caffeine acts as an appetite suppressant. This caution regarding children and caffeine speaks directly to the issue of marketing energy drinks to young people that we'll explore in a moment.

Like many industries that are not regulated, the energy drink industry would like to keep it that way and has vigorously resisted imposition of governmental standards on quality or ingredients, including labeling standards. Interestingly, while sodas are limited to 71 milligrams per 12-ounce serving, there are currently no restrictions on the amount of caffeine an energy drink can contain.

In the fall of 2008, one hundred scientists and physicians sent a letter to the Food and Drug Administration, asking for more regulation of energy drinks based on their caffeine content, noting that young drinkers may be at possible risk for caffeine intoxication and higher rates of alcohol-related injuries.

A third breed of energy drink (along with non-alcoholic energy drinks and sports drinks that contain carbohydrates for energy) combines caffeine and other stimulants with alcohol. When someone consumes too much alcohol, their head spins and they feel tired. Energy drinks cancel out these warning signs. The person feels good and therefore keeps drinking without realizing they are drunk or may drive a car because they are simply unaware that their reflexes may be too impaired for them to drive safely. In addition, the non-alcoholic and alcoholic versions of the drinks are often marketed side by side, making it more possible to make the wrong selection.

In early 2008 Anheuser Busch was forced to reformulate several of its alcohol/caffeine combo drinks after an eleven state investigation charged that they were marketing the drink to minors and misrepresenting health benefits.

U.S. energy drink sales topped $6 billion in 2006, according to Goldman Sachs. The most popular drink, Red Bull, reportedly generates over $1 billion in sales annually. Drink makers target teens and young adults, promote the performance-enhancing and stimulant effects of energy drinks and equate drink use with coolness and popularity. One product, Go Girl, comes in a pink can and advertises as sugar-free and containing a mild appetite suppressant, clearly appealing to young woman who want both energy and weight control.

Many teenagers don't have enough information about the effects of energy drinks' ingredients. "If they use it for three or five days in a row, and then suddenly quit, then they're going to be thrown into withdrawal," says Roland Griffiths, professor of behavioral biology at Johns Hopkins University.

Moreover, a 2008 study of 1,253 college students found that energy drink consumption significantly predicted subsequent non-medical prescription stimulant use, raising the concern that energy drinks might serve as "gateway" products to more serious drugs of abuse.

The combination of no labeling requirements, significant side effects and complications from excessive use and indications that young adults will move from these drinks to stronger stimulants creates a disturbing backdrop to the popularity of energy drinks.

Very simply, energy drinks provide a possibly performance-enhancing energy boost wrapped in a pleasant, convenient to buy and carry, beverage. Most energy drinks do not contain more than the recommended moderate level of caffeine intake for a normal adult. For some audiences, the energy drink creates a fun, legal high that can be shared with others, not unlike the morning coffee klatch, huddled around a steaming pot of java or the hordes of Americans who stop by a Starbucks or Dunkin Donuts at all hours of the day or night for a quick pick me up.

Secondly, although research documentation is thin, there is some evidence that the addition of other ingredients such as amino acids and herbal extracts combine to create a better, safer boost than their caffeine equivalent.

The bottom line seems to be that informed, thoughtful use of energy drinks can be a great way to get a short term energy boost. However, if you plan to use an energy drink, make sure you know how much caffeine you are actually ingesting and don't risk mixing your energy beverage with alcohol.