High Expectations
The producers of energy drinks often make many claims about the health effects of their products, from the expected energy boosts to enhanced mental acuity to calorie-burning for weight loss. While most of these types of drinks do deliver on their promise of a temporary energy spike, it is most often due simply to the caffeine and sugar content, and could be similarly achieved with a strong cup of coffee. Notably, these energy bursts are often followed by an energy "crash" or lull. There also seems to be scant scientific support for the additional ingredients that producers often add to make the kind of claims they do in hyping their products. Taurine, for example, which is frequently added to energy drinks, is an amino acid essential to growth in infants, but a number of scientists say that large amounts provide no advantage to ordinary adults whatsoever.
Hazardous or Hype?
Little conclusive research has actually been published so far on the health hazards of energy drinks. However, their high concentration in ingredients such as caffeine and taurine worries some medical specialists who suspect that long term use may cause unwanted side-effects. The only possible physically addictive ingredients in most of these drinks are caffeine and guarana, which can cause a physical addiction in large doses or with prolonged use. Since withdrawal from both is usually mild, mainly involving headaches, addiction to energy drinks is mostly psychological.
One of the more pressing concerns is the still-popular trend of mixing energy drinks with alcohol. Because alcohol is a depressant and caffeine is a stimulant, some say that combining the two is a bad idea, and asking for trouble. Both caffeine and alcohol are diuretics that can lead to dehydration, and the energy boost from the caffeine may mask the effects of drinking only superficially, comparable to using coffee to sober up - which just makes you feel more energetic, without decreasing the effects of inebriation.
The Bottom Line
The bottom line is that while energy drinks are not necessarily harmful, many just don't live up to most of the claims they make. They are often big on style, low on substance, and ridiculously overpriced. It is perhaps best to think of them as drinks that are highly concentrated in sugar and caffeine, for moderate and occasional use only.