Energy drinks —What you need to know!

By Amy Eichner, Ph.D. and Erin Hannan

Viewpoints presented in SMB commentaries reflect opinions of the authors and do not necessarily reflect positions or policies of ACSM.

Amy Eichner, Ph.D., is Special Advisor on Drugs and Supplements at the U.S. Anti-Doping Agency, where her responsibilities include their dietary supplement policy and providing related education to their stakeholders. Dr. Eichner previously led USADA’s Drug Reference Department. Prior to joining USADA, she conducted medical research at Harvard University and Massachusetts General Hospital. During the period immediately before coming to USADA, she directed an accredited calibration and testing laboratory dedicated to biocompatibility testing of medical devices for the Therapeutic Goods Administration in Australia.

Erin Hannan is Communications and Outreach Director for the U.S. Anti-Doping Agency. Her work focuses on ensuring that competing athletes and our nation’s youth are equipped with tools and skills for making healthy, informed and ethical choices for their lives. With a background in enterprise marketing, branding, communications and outreach initiatives, her responsibilities at USADA include facilitating communications with competing athletes to foster ethical, healthy and informed behaviors, as well as developing comprehensive educational resources to promote these aims.

This article first appeared in the April 2012 e-newsletter of the Professionals Against Doping in Sports. The PADS initiative is jointly led by ACSM and USADA. This topic has broad relevance to many exercise and sports settings, so it is also being presented here for our SMB readers. For more about PADS and to become a subscriber to the PADS newsletter, see the website at:

You may already know this, but there are significant differences between sports/electrolyte drinks (those that contain carbohydrates and electrolytes) and the "Energy” drinks that are now all the rage. But what you may not know is just how significant, and potentially serious, these differences can be. All of these names for drinks can be confusing – don’t be fooled. The ingredients can be deceiving. If your patients are drinking something that advertises itself as an “Energy Drink,” they are probably helping themselves to a healthy (or more likely unhealthy) dose of stimulants. A more proper name for this class of drinks could be “Stimulant Drinks.”

Energy for Sports Performance
Before we go further, let’s remember how basic nutrients provide energy for muscular activity and performance. Glucose is the body’s prime source of fuel for regenerating ATP, which is the essential energy currency required of athletes performing high intensity exercise. Carbohydrates (sugars) are a direct source of glucose, but the body can also make glucose by burning amino acids and fats. Glucose is like the coal in a power plant. When our bodies need more energy, they burn more glucose, just like when energy needs in a city increase, more coal is burned (or nuclear fuel, or gas - you get the picture).

In contrast, stimulants bind to neurons and activate them. But stimulants cannot substitute for glucose or the energy it produces. Using the analogy above, when you consume stimulants, it’s as if airflow to coal in the furnace of a power plant were suddenly and greatly increased. Yes, you get a big increase in the amount of energy being released but only because you are burning the coal up all at once. When the coal is gone, it’s gone. Stimulants make people feel like they have more energy but it is mostly because it is all being burned up at once.

Dissecting a Label
When was the last time you carefully examined an ingredient label for an “energy” or stimulant drink? Take a look at this example. If you bought this drink, would you actually know what you were drinking? Would your patients?

Looking at the label above, would you have known that tyrosine and phenylalanine, ingredients commonly added to energy products, can interact with a lot of medications? One of the ingredients, methylsynephrine, is a stimulant that is on the World Anti-Doping Agency (WADA) Prohibited List. If a patient asked you to describe what the different ingredients are for, would you be able to advise them? Do you know where the ingredients come from? Did you know that Kola Nut and Guarana are both sources of caffeine? Can you tell how much caffeine is in one serving of this product? Did you know that citrus aurantium (also called bitter orange) contains synephrine which also has stimulant properties? Synephrine is not prohibited, but added together with all of the other ingredients, could cumulatively pose health dangers.

Did you know Yohimbe interacts with anti-depressants? Did you know that Ma Huang is the plant source for ephedra? Ephedra is an extremely strong stimulant that was taken off the market years ago by the FDA because it caused many adverse health effects and even some deaths. Nonetheless, ephedra is still finding its way into dietary supplements.

Stimulants can cause positive anti-doping tests
There are several stimulants that are on the WADA Prohibited List that pop up in dietary supplements and sometimes in stimulant drinks. Take a look at the examples below. It is possible that your patients may be unwittingly drinking one or more of these prohibited ingredients.

On the Prohibited List as: But sometimes also called:
Methylhexaneamine Geranium (extract, stems, or oil), geranamine, “geranium surge” and other madeup names. 1,3-Dimethylamyline, dimethylpentylamine.
Octopamine ß,4-Dihydroxyphenethylamine; p- Hydroxymandelamine; ND-50; Noroxedrine; p-Norsynephrine
Oxilofrine Methylsynephrine
Phenpromethylamine Fenprometamina; Phenpromethamine; Phenpromethaminum; Phenylpropylmethylamine; “Benzedrine.” Benzedrine itself is an amphetamine like stimulant,but it seems the name may also be used as code for phenpromethylamine. Acacia rigidula (the ingredient label may list this plant but the product might have phenpreomethylamine and other substances in it).

Keep in mind that stimulants are prohibited as a category for those athletes being tested during a competition (except for caffeine and synephrine, neither of which are currently prohibited, but are both in the WADA Monitoring program). The example product and label discussed earlier could cause a positive anti-doping test. Stimulants in dietary supplements are not limited to what you find in bottles or cans on shelves - they can also come in powder form that can be mixed up by the user. They are also found in the grocery check-out line decorated with bracelets and other gimmicks to attract young consumers.

Physicians speak out on dangers of energy drinks
The American Academy of Pediatrics has discouraged the use of energy drinks by children and adolescents. Even caffeine can cause neurological and cardiovascular problems, and should be avoided. This AAP report can be read on

And for a chilling real-life example of the dangers of such drinks read: Dakota Sailor’s story on ESPN. This high school football star nearly died after drinking two cans of a widely distributed commercial beverage labeled as a ‘high performance energy drink.’