Some scientists at the Johns Hopkins Medical Institutions, considered experts on caffeine because of their decades-long study of the stimulant, say the high concentration of caffeine in a growing number of “energy” drinks is enough to cause caffeine intoxication and other health concerns.  In an article published in the September issue of the journal, Drug and Alcohol Dependence, the scientists call for warning labels to be placed prominently on all such beverages that contain caffeine in any amount.

Author Roland Griffiths, PhD, says some energy drinks contain as much caffeine as 14 cans of Coca-Cola but most of them don’t mention caffeine on their labels nor do they warn of any potential health risks, including caffeine intoxication.  Caffeine intoxication is a globally recognized medical syndrome characterized by anxiety, gastrointestinal discomfort, insomnia, nervousness, psychomotor agitation (pacing and restlessness), rapid heartbeat (tachycardia), tremors, and sometimes even death, although fatal cases of caffeine intoxication are rare.

The energy drink industry is estimated to bring in $5.4 billion in annual sales in the United States alone and has seen expansion at a rate of about 55% each year.  By marketing these beverages as dietary supplements, not soft drinks, the industry skirts the federally mandated label requirements for foods and beverages.

Another matter that alarms the Johns Hopkins scientists is the direct marketing to teenagers and young adults in which the beverages are promoted as performance enhancers and stimulants, particularly appealing to college students.  Data from US poison control centers indicate bad reactions from caffeine abuse is often associated with energy drinks.

A survey of 496 college students taken in 2007 reveals the popularity of these beverages on campus:

• 51% of students polled said they’d consumed at least one energy drink during the month prior to the survey;
• 29% of the students using energy drinks reported “weekly jolt and crash episodes;”
• 19% described heart palpitations after drinking these beverages; and
• 27% said they mixed energy drinks with alcohol at least once in the month prior to the survey.

The mixture of alcohol and energy drinks is of particular concern, according to the article.  Its authors fear the energy drinks serve as a gateway to more dangerous stimulants, such as amphetamines and Ritalin (methylphenidate).  A study conducted in 2008 involving 1,253 college students revealed a very high likelihood that students who consume energy drinks would later turn to stronger prescription-strength stimulants for non-medical uses.

The marketing ploys of some energy drink manufacturers turn to the lingo of street drugs, too, another move that is of concern to the Johns Hopkins scientists.  One drink additive called “Blow” is a white powder packaged in vials similar to those used in the cocaine trade.  Even more blatant is the energy drink called, simply, “Cocaine.”

The average 12-ounce serving of a cola drink contains about 35 milligrams (mg) of caffeine, with 71 mg per 12-ounce serving as the highest amount allowed for a soft drink.  A 6-ounce cup of coffee can contain anywhere between 80 and 150 mg.  The caffeine content of many energy drinks range from 50 mg to 500 mg or more.

Source: Johns Hopkins Medical Institutions