5 Secrets You Don’t Know About Energy Drinks

energy drinksWith sleep constantly challenged by the demanding nature of our daily lives. Many of us resort to energy drinks and other caffeinated beverages to power through the day. But do you ever wondering how your body is affected by these drinks? Are they healthy? Moreover, are they safe?

Below are five crucial facts that you need to know before consuming your next energy drink. Knowing these facts could benefit your health and potentially save your life.

1. Energy drinks require no FDA preapproval when choosing ingredients

Traditional sodas are considered to be beverages, and therefore are subject to strict FDA regulations on caffeine contents and ingredients. On the other hand, energy drinks are classified as dietary supplements, and have avoided many FDA regulations due to a loophole created by the Jolt Cola beverage company. Because of this, energy drink ingredients must be listed, however there’s no requirement to list the specific amount of each ingredient existing in these “drinks”.1

2. Per ounce, energy drinks can contain over 5x more caffeine than regular coffee

Energy shots, like 5-Hour Energy, contain 100 mg of caffeine per ounce as compared to regular coffee, which contains approximately 18 mg of caffeine per ounce.2 What does this mean for the typical energy drink consumer?

Well, unlike hot coffee, which is often sipped slowly, energy drinks tend to be “gulped,” and are finished quickly. Therefore, the peak caffeine level of an energy drink will be reached quickly. With a long half-life, energy drink users can quickly find themselves in danger of reaching very high levels of caffeine in the body, especially after consuming several drinks in a short amount of time.

3. The half-life of caffeine in energy drinks can last up to 10 hours

The human body absorbs 99% of caffeine, reaching peak levels within 30-75 minutes.3,6 How long does this caffeine rush last? Well the half-life of caffeine can vary dramatically, with its effects lasting anywhere from 2.5–10 hours.4 There are several factors that can influence the half-life of caffeine, such as: 3-7

    • Impaired liver function
    • High levels of caffeine consumption (increases half-life)
    • Cigarette smoking (decreases half-life)
    • Weight
    • Age
    • Medications (i.e. oral contraceptives, antibiotics, theophylline, Echinacea)
    • Health Status
    • Gender
    • Individual differences

4. A variety of physiological side effects are associated with heavy caffeine use

There are no hard and fast rules on how much caffeine is safe, as caffeine sensitivity can vary widely depending on the individual; however, several major medical organizations have published guidelines for caffeine intake. For example, the Mayo Clinic recommends that people consume no more than 200-300mg of caffeine per day, which equates to roughly one 5-Hour Energy Shot.

In fact, one study found that people given a 300 mg shot of caffeine experienced the following symptoms (in order of prevalence):

    • Restlessness or muscle tremor
    • Heart palpitations
    • Dizziness
    • Headache
    • Diarrhea
    • Wakefulness
    • Polyuria (excessive urination)
    • Increased sweating
    • Abdominal pain
    • Ear/eye problems
    • Vomiting or nausea
    • Delirium

5. Energy drinks have been linked to death and cardiac failure

Between 2004 and 2012, 5-Hour Energy amassed 92 incident reports with 13 fatalities, Monster had 40 reports with 5 fatalities, and Rockstar had 13 reports with no fatalities. Over 50 of the incidents for all three energy drinks list heart problems (chest pain, arrhythmia, cardiac arrest, etc.) in the events, according to the U.S. Food and Drug Administration.

In 2012, Monster Energy received a great deal of attention, when the FDA published a report listing

Monster Energy drinks as a possible contributing factor to the deaths of five people over three years. One of those people was a 14-year-old Maryland girl, whose death certificate stated that she died of “cardiac arrhythmicity due to caffeine toxicity” after drinking two 24-ounce cans of Monster in 24 hours, which exacerbated a pre-existing heart condition. The family of the girl is now suing Monster Energy for failing to provide adequate warnings about the risks of consuming their drinks.

It can’t be all bad, right?

While the majority of studies published on energy drinks focus on the negative effects, not everyone agrees with their assessments. For example, energy drinks do appear to enhance physical performance. Drinking energy drinks also improves driving performance in sleepy subjects – including reducing driving mistakes, swerving, and self-reported sleepiness and alertness.9

So is it safe to have an energy drink?

Bottom line: Yes, but use energy drinks in moderation. If you can’t get going in the morning or are dragging during the middle of your night shift, an energy drink now and then is fine. But remember, whether you get your caffeine from energy drinks, soda, or coffee, read the labels (or do some research) and be aware of the levels of caffeine and other ingredients you’re putting in your body. As long as you use caution and keep track of what you’re consuming, feel free to enjoy the benefits of energy drinks – without ignoring the risks.

Want to learn more about energy drinks? Visit CIRCADIAN to download a free white paper titled

Energy Drinks: The Good, the Bad, and the Jittery that provides further information about energy drinks.


1. Energy “Drinks” and Supplements: Investigations of Adverse Event Reports. U.S. Food and Drug Administration. http://www.fda.gov/Food/RecallsOutbreaksEmergencies/SafetyAlertsAdvisories/ucm328536.htm. Accessed June 20, 2014.
2. Caffeine in coffee: US Food and Drug Administration
3. Carrillo JA and Benitez, J (2000) Clinically significant pharmacokinetic interactions between dietary caffeine and medications. Clinical pharmacokinetics, 39: 127-153.
4.Kaplan GB, Greenblatt DJ, Ehrenberg BL, Goddard JE, Cotreau MM, Harmatz, JS and Shader RI (1997) Dose-dependent pharmacokinetics and psychomotor effects of caffeine in humans. Journal of Clinical Pharmacology, 37:693-703.
5.Caffeine. How much is too much? Mayo Clinic. http://www.mayoclinic.org/healthy-living/nutrition-and-healthy-eating/in-depth/caffeine/art-20045678. Accessed on June 20, 2014.
6.Mandel, HG (2002) Update on caffeine consumption, disposition and action. Food and Chemical Toxicology, 40:123
7.Magkos F, and Kavouras S (2005) Caffeine use in sports, pharmacokinetics in man, and cellular mechanisms of action. Crit Rev Food Sci Nutri 2005, 45: 535-562.
8.Carrillo JA and Benitez J (1996) CYPlA2 activity, gender and smoking, as variables influencing the toxicity of caffeine. British Journal of Clinical Pharmacology, 4(1): 605-608.
9.Reyner LA, and Horne JA (2002) Efficacy of a ‘functional energy drink’ in counteracting driver sleepiness. Physiological Behavior, 75(3): 331–335.

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