The Cooper Institute

Founded in 1970 by the "Father of Aerobics"
Kenneth H. Cooper MD, MPH


Energy Drinks: Friend or Foe?

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Wednesday, Feb 28, 2018

Energy drinks first came on the scene over a quarter of a century ago, and have become a major global industry; this is particularly true among the younger segments of the population. My wife and I noticed this firsthand while making weekend college visits with our two children during the spring of their junior year of high school. We noticed that every medium-to-large sized school we toured had a highly visible outdoor energy drink booth/display offering free samples and discount coupons.

Surveys have indicated that the use of energy drinks is prevalent not only among college and high school students, but also among office workers, recreational and competitive athletes, service members, and first responders. Because there have been reports of adverse effects associated with the use of energy drinks, The American College of Sports Medicine (ACSM) recently published a Special Communication entitled “Energy Drinks: A Contemporary Issues Paper.” Within this blog, we will summarize some of their findings and key recommendations.

First, let’s define what is meant by an ‘energy drink’ in the context of the ACSM paper. Energy drinks are defined as beverages that typically contain moderate to high amounts of caffeine. Various combinations of amino acids, taurine, vitamins, and herbs may also be present. Some energy drinks contain sugar, while others do not, and the drink may or not be carbonated. Within this context, energy drinks should not be confused with soft drinks, sodas, flavored water, or sports drinks. Although energy drinks represent a multibillion dollar industry, rigorous studies on the safety and efficacy of these drinks is very limited.

The major health concern regarding energy drinks is their caffeine concentration. It is interesting to note that while the FDA imposes limits on the caffeine concentration of soft drinks (maximum of 20 mg caffeine per 3 ounces), no such limits exist for energy drinks. In fact, small volume energy drink ‘shots’ can contain as much as 12 times the caffeine concentration limit of soft drinks! The fact that energy drinks are chilled, sweetened, and consumed rapidly, sometimes during sporting events, raises important issues regarding adverse events. The most common adverse events that have been reported with energy drinks are elevated and/or irregular heartbeat, unusually high blood pressure, anxiety, upset stomach, restlessness, mind racing, and jitteriness. Less commonly reported adverse events have included seizures, acute renal failure, rhabdomyolysis, metabolic acidosis, and death. The more serious events typically occur when individuals consume multiple energy drinks within a short period of time. It has been shown that when consumed with alcohol, energy drink users tend to consume more alcohol and tend to be prone to more risky behavior than when drinking alcohol by itself. The ACSM paper pointed out that the FDA and U.S. Poison Control Center have received more than 700 reports of adverse events associated with the use of energy drinks, with many of these events occurring in children under the age of 6 (what are parents thinking?).

This number becomes exponentially higher when you consider that the FDA reporting system only captures approximately 1% of true adverse events!

Here is a summary of the key ACSM Recommendations regarding energy drinks:
  • Warnings should be prominently displayed on the front of products stating vulnerable populations, including those younger than 18 years, pregnant or breastfeeding women, caffeine naïve* or sensitive individuals, taking stimulant or caffeine-based medications, or those with certain cardiovascular or medical conditions, should avoid energy drink use.
  • Regulatory actions are needed regarding limits on the caffeine content of energy drinks, as well as clear labeling to identify the actual amount of caffeine contained per serving.
  • Marketing should not appeal to vulnerable populations, specifically children and adolescents.
  • Standard safety and efficacy studies should be performed and submitted to the FDA by manufacturers.
  • More careful monitoring of adverse events related to energy drink consumption is needed to fully understand the rate, severity and nature of reactions to these products across the lifespan.
  • Although most healthy adults can consume an energy drink without any significant, negative, acute health effects, the long-term effects of chronic consumption have not been well studied.
On a personal note, I had an adverse experience with caffeine many years ago while studying for a Biochemistry exam during my time as a Master’s Degree student at the University of South Carolina. I was caffeine naïve at the time. I decided to stay up late to study, and had heard that drinking lots of coffee would help me stay awake. Within 30 minutes after rapidly consuming 3 cups of coffee, my heart began pounding and racing. I felt jittery, sad, and anxious for the next few hours, and found it very difficult to concentrate. While I passed my exam the following day, this caffeine experience was extremely unpleasant. Since that time I have been very careful to limit my caffeine intake to the bare minimum!

*a caffeine naïve person is one who is not accustomed to consuming caffeine. 

Higgins, J.P., Babu, K., Deuster, P.A., Shearer, J. Energy Drinks: A Contemporary Issues Paper. (2018). Current Sports Medicine Reports, 17:2, 65-72.

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