Health effects
A review published in 2008 found no documented reports of negative or positive health effects associated with the amount of taurine used in energy drinks, including Red Bull, concluding that "The amounts of guarana, taurine, and ginseng found in popular energy drinks are far below the amounts expected to deliver either therapeutic benefits or adverse events. However, caffeine and sugar are present in amounts known to cause a variety of adverse health effects."[22] Another publication found that "the number of available publications that really go into the details in this topic is also rather poor".[23]
Commonly reported adverse effects due to consumption of the levels of caffeine used in the quantities commonly present in Red Bull can result in a state of central nervous system over-stimulation called caffeine intoxication (DSM-IV 305.90),[45] or colloquially the "caffeine jitters". The symptoms of caffeine intoxication are not unlike overdoses of other stimulants. It may include restlessness, fidgetiness, nervousness, excitement, euphoria, insomnia, flushing of the face, increased urination, gastrointestinal disturbance, muscle twitching, a rambling flow of thought and speech, irritability, irregular or rapid heart beat, and psychomotor agitation.[42] In cases of much larger overdoses, mania, depression, lapses in judgment, disorientation, disinhibition, delusions, hallucinations, psychosis, and rhabdomyolysis (breakdown of skeletal muscle tissue) can be provoked.[46][47] Extreme overdose can result in death.[48] (see Health effects of caffeine). For drinking Red Bull in excess and side-effects (see Caffeine intoxication). A 2008 position statement issued by the National Federation of State High School Associations made the following recommendations about general energy drink consumption for young athletes:[24]
Water and appropriate sports drinks should be used for rehydration as outlined in the NFHS Document “Position Statement and Recommendations for Hydration to Minimize the Risk for Dehydration and Heat Illness.”
Energy drinks should not be used for hydration. Nor should they be used for performance enhancement.
Information about the absence of benefit and the presence of potential risk associated with energy drinks should be widely shared among all individuals who interact with young athletes.
Energy drinks should not be consumed by athletes who are dehydrated.
Energy drinks should not be consumed, without prior medical approval, by athletes taking over the counter or prescription medications.
[edit] Cardiovascular effects
The results of a study showed that the ingestion of one, 250mL can of sugar-free Red Bull, in a sample of 30 healthy young adults, had an immediate detrimental effect on both endothelial function, and normal blood coagulation. This temporarily raised the cardiovascular risk in these individuals to a level comparable to that of an individual with established coronary artery disease.[13]
Based on their results, researchers involved with the study cautioned against the consumption of Red Bull in individuals under stress, in those with high blood pressure, or in anyone with established atherosclerotic disease.[25] Red Bull representatives, however, stated that this observed increase in cardiovascular risk was not felt to be different from that associated with drinking a regular cup of coffee.[26] They also stated that they believed that Red Bull must be safe, as it was felt the only way Red Bull could have such substantial global sales is if various health authorities had concluded the drink safe to consume.
There has been at least one case report of Red Bull overdose causing postural orthostatic tachycardia syndrome in a young athlete.[27] A February 3, 2009 article in The Daily Telegraph called, "Red Bull 'may have triggered heart condition that killed student'" reported on the death of a 21 year-old woman who died after drinking four cans of Red Bull as well as alcohol at "social levels".[28] It was believed, but had not been proven, that she suffered from a rare heart condition called long QT Syndrome.[28] She was on medication for epilepsy. A medical examination found that there were no illegal drugs in her system. The article quoted a doctor as saying, "The QT levels may have grown over a few years, or it may have been artificially pushed over the limit by caffeine".[29]
[edit] Caffeine content
The caffeine content of a single can of Red Bull is 80 mg/250 ml.[30][31] This is about the same as a normal coffee, or slightly less depending on the brewing method.[32] The actual caffeine level in Red Bull can vary depending on country, as some countries have legal restrictions on how much caffeine is allowed in drinks.
As is the case with other caffeinated beverages, Red Bull drinkers may experience adverse effects as a result of overuse.
