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A Can of Bull

Do Energy Drinks Really Provide a Source of Energy?

Co Authors:

Merle K. Heidemann
College of Natural Science, Emeritus
Michigan State University

Gerald Urquhart
Lyman Briggs School of Science
Michigan State University


This case study is designed to teach students at various levels about large biomolecules, nutrition, and product analysis. Students conduct a biochemical analysis of several popular energy drinks on the market, which many students purchase at fairly high prices, and determine whether these products nutritionally match their marketing claims. The case can be used as a review of basic biochemistry and nutrition for upper level students in physiology, biochemistry, or nutrition courses, or to introduce this information in introductory level courses in these disciplines.

  • Describe and categorize chemically the components of various popular “energy drinks.”
  • Determine the physiological role of these components in the human body.
  • Explain scientifically how the marketing claims for these drinks are supported (or not).
  • Determine under what conditions each of the “energy drinks” might be useful to the consumer.
  • Write an analysis of energy drinks for a popular magazine.
Keywords: Energy drink; metabolism; food energy; glycolysis; stimulant; caffeine; substance use; nutrient; calorie; Krebs cycle; oxidative phosphorylation; adenosine triphosphate; ATP; Citrus Blast; Red Bull; Adrenaline Rush; Impulse; advertising; marketing claims
Topical Area: Scientific argumentation, Science and the media
Educational Level: High school, Undergraduate lower division, Undergraduate upper division
Formats: PDF
Type/Method: Interrupted
Language: English
Subject Headings: Biochemistry   Nutrition   Physiology   Biology (General)  
Date Posted: 06/20/05
Date Modified:
Copyright: Copyright held by the National Center for Case Study Teaching in Science, University at Buffalo, State University of New York. Please see our usage guidelines, which outline our policy concerning permissible reproduction of this work.

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I am teaching an introductory biology course to 17 freshman students and we are doing eight cases as part of the class. We just completed the case study entitled "A Can of Bull? Do Energy Drinks Really Provide a Source of Energy?" (which we thoroughly enjoyed), and I have a few comments about it. First, my students would have liked the authors of the case to add Gatorade®. Second, some estimate of costs might be interesting. Third, it would be good to discuss the role of unproven herbal remedies like Echinaceae or ginseng or ginkgo, many of which are found in the energy drink Citrus Blast® at least.

I had the class split into five groups, one for each drink. Each group had to analyze their drink, turn in a short paper about it, and then tell the class about their drink. We filled out a chart (energy / amino acids / vitamins and stimulants / other) on the board for each drink. Next time I will probably split vitamins and stimulants, and maybe add a column for herbals. We didn’t examine ingredients like l-taurine in depth, although I would discuss them further in a more advanced course.

One student pointed out that if there really was a sugar high, then untreated diabetics should be really active. Another student commented that he would have liked to have known how much caffeine was in each drink.

Eric Ribbens
Department of Biology
Western Illinois University
Macomb, IL
I’ve used this case with my Rhetoric and Science students to illustrate the differences between the persuasive power of advertising and the kinds of arguments made with scientific data. These students had been drilled about appropriate uses of data, although not all of them had taken college level courses in chemistry.

This evening, I noticed the following article about lawsuits against the Coca-Cola Corporation over its marketing of VitaminWater as a “healthy alternative” to sodas; thought you might find it an interesting addition to the case:

Lili Fox Vélez, Ph.D.
Biomedical Writing Track / Professional Writing Program
Towson University
Towson, MD
I have used this lesson with biology 2 students as a way to make connections with the real world.

Kathryn Cross
Broadmoor High School
Baton Rouge, Louisiana
This is an excellent case study! Have you (or any other teachers) created a marking guide/rubric for the final assessment? It would be great to have that included with the case as well. Thanks for sharing such a great educational resource!

Jennifer Osmond
Northeast Kings Education Centre
Canning, Nova Scotia, Canada
I assigned this article to my Pre-AP Biology students as our first case study reading about halfway through our first unit (Biomolecules). It really allowed the students to research and learn first-hand about the sources of "energy" from these popular energy drinks and why our administration has banned them from on-campus vending machines. In addition, my students seemed to be empowered in the ability to dispel multiple myths about the use of energy drinks for health reasons and idea of sugar highs.

Abbigail Damron
Science Department
Wills Point High School
Wills Point

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