Energy Drinks

What are Energy Drinks?

Energy drinks are canned or bottled beverages sold in convenience stores, grocery stores, and bars and nightclubs (in mixed drinks). Most energy drinks are carbonated drinks that contain large amounts of caffeine and sugar with additional ingredients, such as B vitamins, amino acids (e.g. taurine), and herbal stimulants such as guarana.

Energy drinks are marketed primarily to people between the ages of 18 and 30 as a stimulant, which is why energy drinks have names that convey strength, power, and speed, and sexuality, such as:

• Red Bull Energy Drink
  
• Monster Energy Drink
  
• Full Throttle Energy Drink
  
• Amp Energy Drink
  
• XS Energy Drink
  
• Redline Energy Drink
  
• Rock Star Energy Drink
  
• Spark Energy Drink

History of Energy Drinks

Although sales of energy drinks in the United States were $3.5 billion in 2005, according to Beverage Digest, the category was only recently created with the launch of the Red Bull Energy Drink.

Red Bull was created by Dietrich Mateschitz, an Austrian who adapted the energy drink from a Thai beverage called Krating Daeng, a popular drink with rickshaw drivers in Thailand. The key ingredient in the Thai energy drink was taurine, an amino acid that was first discovered in bulls (this association is responsible for the Red Bull urban legend that the drink's active ingredient is bull urine or semen). Red Bull was introduced to Europe in 1987 and to the United States in 1997.

Energy Drinks Contain Caffeine

Red Bull, one of the most popular energy drinks, contains nearly 80 mg of caffeine per can, about the same amount of caffeine as a cup of brewed coffee and twice the caffeine as a cup of tea. Other energy drinks contain several times this amount. The amount of caffeine in an energy drink isn't always indicated on the label, so it is difficult to gauge how much one is consuming.

Another problem with energy drinks is that unlike hot coffee or tea, which is sipped slowly, it's common for typical energy drink consumers to drink large amounts quickly.

Some people are sensitive to caffeine and experience anxiety, palpitations, irritability, difficulty sleeping, and indigestion with relatively small amounts. People with heart conditions should avoid large amounts of caffeine, because it is a stimulant.

The Combination of Ingredients in Energy Drinks Has Not Been Studied

One of the biggest concerns is that we just don't know enough about the effect of the combination of ingredients in energy drinks. Many ingredients are believed to work synergistically with caffeine to boost its stimulant power.

For instance, one can of Red Bull contains 1000 mg of taurine. A German double-blind study compared a taurine and caffeine drink, a caffeine-only drink, and a placebo drink. Stroke volume--the volume of blood ejected with each beat of the heart--was increased only in the group taking the taurine-and-caffeine drink. Taurine appears to play an important role in muscle contraction (especially in the heart) and the nervous system.

Red Bull also contains 600 mg of glucuronolactone, a substance that is naturally found in the body. There is a lack of published information on the health effects of glucuronolactone supplementation in humans or on the safety of this combination.

Energy drinks contain sugar (although sugar-free energy drinks are now available), because it is a quick source of energy.

B vitamins are sometimes added to energy drinks in small amounts. It makes energy drinks appear healthy, although they probably contribute little. B vitamins are needed to convert food into energy.

Some energy drinks contain guarana, a South American herb that is an additional source of caffeine.

Energy Drinks Should Not Be Mixed With Alcohol

Red Bull and vodka has become a popular mixed drink at bars because it has a reputation for reducing the depressant effects of alcohol (e.g. fatigue) while enhancing the "feel good" buzz. But while people may not feel impaired, their blood alcohol concentration is still high. People may consume larger amounts of alcohol as a result.

A study compared the effects of alcohol alone to an alcohol plus energy drink combination. Researchers found that the alcohol plus energy drink significantly reduced subjective alcohol-related symptoms such as headache, weakness, dry mouth, and impairment of motor coordination, even though breath alcohol concentration and objective tests of motor coordination and reaction time didn't reflect this.

The caffeine in energy drinks is also dehydrating, which may slow the body's ability to metabolize alcohol.

Energy Drinks Should Not Be Consumed During Exercise

Energy drinks should not be confused with sports drinks such as Gatorade, which are consumed to help people stay hydrated during exercise. Sports drinks also provide carbohydrates in the form of sugar and electrolytes that may be lost through perspiration.

The caffeine in energy drinks acts as a diuretic and promotes dehydration.

A California high school was the first to ban energy drinks after two students experienced dizziness and disorientation after drinking an energy drink before football practice.

Did Depression Offer an Evolutionary Advantage?

A provocative new theory explores the possibility that depression is an evolutionary condition that protected our ancestors — from infection.

Such a theory could explain the ubiquity of depression which affects one in 10 adults in the United States. As such, experts believe the hypothesis that depression is “hard-wired” into our brains must be considered.

This has led biologists to propose several theories to account for how depression, or behaviors linked to it, can somehow offer an evolutionary advantage. Some proposals have focused on how depression influences behavior in a social context.

In a new article, a pair of psychiatrists addresses this puzzle in a different way, tying together depression and resistance to infection.

In this theory, researchers propose that genetic variations that promote depression also helped our ancestors fight infection. An outline of their proposal appears online in the journal Molecular Psychiatry.

Co-authors Andrew Miller, M.D., and Charles Raison, M.D., recognized that depression is often linked to inflammation or an overactivated immune system. People with depression tend to have higher levels of inflammation, even if they’re not fighting an infection.

“Most of the genetic variations that have been linked to depression turn out to affect the function of the immune system,” Miller said. “This led us to rethink why depression seems to stay embedded in the genome.”

“The basic idea is that depression and the genes that promote it were very adaptive for helping people — especially young children — not die of infection in the ancestral environment, even if those same behaviors are not helpful in our relationships with other people,” Raison said.

Until development of sulfa drugs and antibiotics in the early part of the 20th century, infection was a major cause of death. Surviving infection was a key determinant in whether someone was able to pass on his or her genes.

The authors propose that evolution and genetics have bound together depressive symptoms and physiological responses that were selected on the basis of reducing mortality from infection. Fever, fatigue/inactivity, social avoidance and anorexia can all be seen as adaptive behaviors in light of the need to contain infection, they write.

The theory provides a new explanation for why stress is a risk factor for depression. In theory, the stress-depression link is a side-product of a process that pre-activates the immune system in anticipation of injury.

Similarly, a disruption of sleep patterns can be seen in both mood disorders and when the immune system is activated. This may come from our ancestors’ need to stay on alert to fend off predators after injury, Miller said.

Experts believe the new theory could also guide future research on depression. A particular area of focus could be the use of inflammation biomarkers to help predict whether someone will respond to various treatments for depression.

Miller and Raison are involved in ongoing research on whether certain medications, which are normally used to treat autoimmune diseases, can be effective with treatment-resistant depression.