Energy Drinks: What does the research say?

Posted on July 30, 2023

Between 30-50% of adolescents and young adults consume energy drinks. Considered a small component of the non-alcoholic beverage industry, energy drinks are considered the most dynamic in 60% of the market growth. It is estimated that the U.S. sales of energy drinks were $13.9B in 2021 and $63B globally. With these numbers growing, it is important to understand the risks of usage.

The average amount of caffeine in an energy drink is around 80mg per 8.4 fl oz per serving, most cans will contain at least 2 servings. It's recommended by The American Academy of Pediatrics that teenagers between the ages of 13-18 should have no more than 100 mg of caffeine per day. The United States Anti-Doping Agency (USADA) actually suggests we should call Energy Drinks “stimulant drinks”.

Energy drink consumption has been associated with many health problems, including conditions associated with the heart, nervous system, and stomach. Some believe cardiovascular side effects from energy drinks might be related to the drinks' effects on endothelial, or blood vessel, function. Let’s look at what the research says.

Energy Drink Research

Dr. John Higgins recently studied 44 non-smoking, healthy medical students in their 20s by testing their endothelial function before each of the students drank a 24-ounce energy drink. One and a half hours after consuming the energy drink, researchers checked their artery flow mediated dilation (an ultrasound measurement that indicates blood vessel health). It was found that vessel dilation was 5.1% before the energy drink and dropped to 2.8% after, indicating an acute impairment in vascular function. Essentially, blood vessel constriction is occurring after consuming these drinks, which is negatively impacting blood flow. What’s more alarming is researchers are not sure what the exact mechanism of action is but hypothesize it may be due to the combination of ingredients.

Recently we released a 30 Minute podcast with Dr. Higgins where we and Sports Dietitian, Tavis Piattoly, discuss his findings and they’re quite eye opening. Please take a half hour of your day to tune in and learn more about this important topic:

The standard energy drink with 80-250 mg of caffeine is not your major concern. The concern lies with products that contain not only high levels of caffeine, but have multiple stimulants like Guarana Seed, Green Tea Extract, Yohimbe, and Yerba Mate. Some drinks may also contain Synephrine, which is on the banned substance list for many professional sporting agencies and the NCAA. Combining high levels of caffeine with other stimulants may cause an electrical disturbance causing a life threating arrhythmia (i.e. heart palpitations). As we’ve seen in several cases in teens and adults, it could potentially lead to cardiac arrest and eventually death.

While energy drink ingredients such as caffeine have been widely studied, others haven’t and manufacturers are using mainly anecdotal evidence as justification of their use in their beverages or other products. Consumers should be aware of the ingredients contained in energy drinks and make educated decisions whether or not these beverages are the best choice for their bodies.

It is also important to advise users to check the label before purchasing them and understand what they are putting into their body. We would love to help you have these conversations. Energy Drinks is one of the topics we cover in our ALL ME Education Programs that we offer. To learn more about these programs, visit To schedule a program directly or for any other questions on this topic, reach out to our Director of Education, Brian Parker, at

About Dr. Higgins

John Higgins, MD, MBA, MPHIL, FACC, FACP, FAHA, FACSM, FASNC, FSGC is a Professor of Medicine at the McGovern Medical School at the University of Texas. He is also a Senior Cardiologist at Lyndon B. Johnson General Hospital and Director of Exercise Physiology at Memorial Hermann Institute for Sports Medicine and Human Performance. He is also a Sports Cardiologist with the Houston Rockets and Rice Athletics. He has appeared over 700 times on local TV and radio including CNN and ABC World News. He is the author of 3 books, 2 book chapters, 55 manuscripts, 308 web-based publications, and 16 abstracts.

Energy Drinks Content and Safety:

Energy Drinks: A Contemporary Issues Paper:

Some Popular Energy Shots and Their Ingredients: Are they safe and should they be used? A Literature Review:

Beverages | Free Full-Text | Some Popular Energy Shots and Their Ingredients: Are They Safe and Should They Be Used? A Literature Review (

Stimulant Containing Energy Drinks: What you need to know? STIMULANT-CONTAINING ENERGY DRINKS: What You Need to Know : ACSM's Health & Fitness Journal (

Energy Drink Effects on Hemodynamics and Endothelial Function in Young Adults.

Energy Drink Effects on Hemodynamics and Endothelial Function in Young Adults - Abstract - Cardiology 2021, Vol. 146, No. 2 - Karger Publishers

Cardiovascular Complications of Energy Drinks:

Beverages | Free Full-Text | Cardiovascular Complications of Energy Drinks (

Endothelial function acutely worse after drinking energy beverage:

Endothelial function acutely worse after drinking energy beverage - International Journal of Cardiology