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5-Hour Energy:

The Healthy Energy Drink?

 Megan Rogers 

October 23, 2008

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Psy 268: Health Psychology

Professor Schlundt

Oct. 10, 2008






5-Hour Energy

“Overworked and sleep- deprived Americans young and old so crave a buzz these days that even alcoholic drinks come loaded with caffeine, and doctors are getting worried. In the past three years alone, the number of 18-to-24-year-olds who drink coffee daily has doubled, from 16 percent to 31 percent-and some of them go on to pop prescription stimulants such as Adderall or Ritalin for late-night study sessions. Energy drinks like Red Bull and Cocaine, with several times the buzz of a can of Coke, have mushroomed into a $3.5 billion-a-year industry” (





The high amounts of caffeine and sugar present in many popular energy drinks have recently become a target for both researchers and the media.  Although the health risks attributed to energy drinks are becoming more and more well known, the perceived need for an “energy boost” often trumps the knowledge of the publicized warnings.  In the advertisements for the new energy “shot”, 5-Hour Energy claims that this product is superior to other types of energy drinks due to its exclusion of guarana and sugar, its modest level of caffeine, and its lack of a resulting “crash-effect” (  In this paper I will address these and other claims made by 5-Hour Energy, review the main ingredients in the product, and assess whether 5-Hour Energy, is, in fact, a healthy alternative to other and more popular energy drinks available to the tired and interested consumer.


Product Claims:

5-Hour Energy is a 2 ounce dietary supplement that was designed to make you feel “awake, alert, and productive for hours—without the jitters and crash associated with other energy drinks” (, perfect for “combating a groggy morning, that afternoon lull, or to motivate you to work out” (  The product’s website, label, and television commercials suggest that its unique blend of vitamins provide a boost of energy and its combination of amino acids provides cognitive enhancements, such as an increased ability to focus and a better mood.  The company that produces 5-Hour Energy, Living Essentials, differentiates their product from other energy drinks in that in 5-Hour Energy “There’s zero sugar, zero net carbs and only four calories.  It contains about as much caffeine as a cup of coffee” (  The lack of sugar and reduced amount of caffeine is supposed to eliminate the “crash effect” (which Living Essentials and 5-Hour Energy defines as a reduction in energy below baseline, see: that most users experience when using other popular energy drinks with high sugar and high caffeine contents.  In addition, 5-Hour Energy is supposed to work “by waking up your brain—not wiring up your body” and last for an average of about five hours ( 

(Commercial for 5-Hour Energy available at:

1994 Dietary Supplement Health and Education Act:

Most energy drinks fall under the 1994 Dietary Supplement Health and Education Act by claiming that the ingredients in the drinks are derived from healthy substances, such as vitamins, herbs and other natural sources.  Under this act, the Food and Drug Administration does not have to regulate the supplements before they are marketed, and it is the manufacturer’s responsibility to make sure the product is safe and effective.  The companies do have to disclose the ingredients found in their products, but for the ingredients included in the “other ingredients” section instead of the “Supplement Facts” section, the specific amounts (such as the amount of caffeine in 5-Hour Energy) does not have to be included (

Ingredients in 5-Hour Energy:

The major ingredients in 5-Hour Energy are:  B Vitamins 6, 12, Niacin, and Folic Acid and an “Energy Blend” that includes Taurine, Glucuronolactone, Malic Acid, Tyrosine, Phenylalanine, Caffeine, and Citicoline (as of October 2007).

Supplement Facts (from label):

Serving Size 2 fl oz.

Amount Per Serving:

% Daily Value




Calories from Fat



Niacin (as Niacinamide)

30 mg


Vitamin B6 (as Pyridoxine Hydrochloride)

40 mg


Folic Acid

400 mcg


Vitamin B12 (as Cyanocobalamin)

500 mcg



10 mg

< 1%

Energy Blend:

Taurine, Glucuronolactone, Malic Acid, N-Acetyl L-Tyrosine, L-Phenylalanine, Caffeine, Citicoline

1870 mg


Daily value not established

Other Ingredients:

Purified water, Natural and Artificial Flavors; Sucralose; Potassium Sorbate, Sodium Benzoate, and EDTA (to protect freshness)



Although the website for 5-Hour Energy includes blurbs about the effectiveness and safety about these ingredients, the following information is derived from non-partisan sources so that a more objective assessment of these ingredients can be ascertained.




Niacin is a water-soluble vitamin, and is also known as nicotinic acid or vitamin B3.  It can be found in many foods, including milk, eggs, fish, meat, and cereal grains.  Niacin is involved with the proper functioning of many oxidation-reduction reactions in the body, including the degradation of carbohydrates, fats, proteins, and alcohol.  They also assist in the formation of macromolecules such as fatty acids and cholesterol (  The recommended daily intake for adolescents (14-18 years) and adults (older than 19 years) is 16 mg/day for males and 14 mg/day for females (Food and Nutrition Board, 1998).  The average dietary intake is about 30 mg/day for men and 20 mg/day for women  (Food and Nutrition Board, 1998).  A side effect of taking niacin at levels as low as 30 mg/day can be a reddening and warming of the skin, called a “Niacin Flush”, and thus the Food and Nutrition Board set the tolerable upper intake level at 35 mg/day for adults and 30 mg/day for adolescents.  5-Hour Energy warns the consumer of the possibility of Niacin Flush on the label of their product.  According to the Mayo Clinic, other, more serious side effects include “liver toxicity, worsening of stomach ulcers, and altered blood sugar or insulin levels or uric acid concentrations” (  

Vitamin B6:

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Vitamin B6 is also a water-soluble vitamin.  It occurs in three compounds, pyridoxine, pyridoxal, and pyridoxamine.  5-Hour Energy uses the first compound, pyridoxine in its product.  Pyridoxine is found in many plant sources, whereas pyridoxal and pyridoxamine are found in animal tissues (Malouf & Evans, 2003).  Foods such as cereal grains, peanuts, bananas, carrots, spinach, potatoes, milk, eggs, fish, and meat contain quantities of vitamin B6.  According to the Mayo Clinic, “Vitamin B6 is required for the synthesis of the neurotransmitters serotonin and norepinephrine and for myelin formation” (  The recommended daily amount for vitamin B6 in adolescents and adults is 1.3 mg/day, and the tolerable upper intake level is 100 mg/day for adults and 80 mg/day for adolescents (Food and Nutrition Board, 1998).  In some cases where B6 supplements were taken at amounts of 500 mg/day for an extended period of time, painful sensory neuropathy was exhibited (  

            In 2003, Reem Malouf and John Grimley Evans with the Cochrane Collaboration organized a systematic review of studies published about B6 and its effects on cognition in order “to assess the efficacy of vitamin B6 supplementation in reducing the risk of developing cognitive impairment by older healthy people, or improving cognitive functioning of people with cognitive decline and dementia, and whether or not vitamin B6 deficiency had been diagnosed” (Malouf & Evans, 2003). Malouf and Evans (2003) found no randomized controlled trails of the effect of B6 on cognition in people with dementia that met the inclusion requirements by the Cochrane Collaboration, but they found and analyzed two studies that measured the impact of B6 on healthy people.  This meta-analysis is relevant to the discussion of 5-Hour Energy because although the supplementation of B6 in people with a deficiency of the vitamin has proven significant in countless studies, the effects of the vitamin in healthy individuals is more difficult to ascertain.

            In the first study, Bryan (2002) measured the effects of B6 on the cognition of two hundred and eleven Australian women.  All of the participants were in good health, did not smoke, did not take hormone-replacement therapy, and were not prescribed any type of medication that could potentially alter mental status.  The women were split into three groups based on age (between 65 years and 92 years) and then randomly assigned to one of four treatment groups.  Each group was given a daily dose of 750 μg of folic acid, or 15 μg of vitamin B12, or 75 μg of vitamin B6, or placebo.  A baseline of cognition was measured and background dietary intakes were assessed before the trial and compared to the results at the end of the experiment.  Standardized neurophysiological tests were used to measure cognitive factors such as speed of processing, working memory, and executive functioning.   

            In the second study, Deijen (1992) used a population of men between the ages of 70 to 79 with a Groninger Intelligence Test score above 80 with good health and limited alcohol use to assess the effects of B6 supplementation on cognition.  The participants were matched by age, B6 intake, and Intelligence score, and then randomly assigned either 20 mg/day of pyridoxine hydrochloride (half the amount in 5-Hour Energy) for twelve weeks or a placebo. 

            Malouf and Evans (2003) concluded that “there is no evidence that vitamin B6 supplementation has any effect on mood or cognitive functions of older people” and that more research needs to be done in this area with the general population and in the long term.  Although the population characteristics of this study do not match the likely consumer population of 5-Hour Energy, the findings are still significant in that it has not yet been shown that B6 supplementation in healthy people causes enhanced cognitive functioning.  Part of this may be due to the fact that B6 is water-soluble, and much of the vitamin is eliminated in the urine. 

Folic Acid:


Folic acid is the synthetic form of the water-soluble vitamin, folate.  Folate is commonly found in cereals, leafy vegetables, bananas, melons, organ meat, orange juice and tomato juice.  A folate deficiency can result in megaloblastic and macrocytic anemia, which is effectively treated with folic acid  (  Folic acid has also been shown to prevent anemia in pregnant women and reduce the risk of neural tube defects in the infant (  The RDA for folate for adolescents and adults is 400 mcg/day.  The Food and Nutrition Board of the Institute for Medicine uses “Dietary Folate Equivalents” when calculating the RDAs, so 400 mcg/day of folate would actually equal only 200 mcg/day of folic acid taken as a supplement ( (half of what is contained in 5-Hour Energy).  The tolerable upper intake level for folic acid was set to 800 mcg/day for adolescents and 1,000 mcg/day for adults.  The reason why the tolerable upper intake levels are set in units of folic acid, not Dietary Folate Equivalents is because there have only been adverse effects associated with the supplemental form of the vitamin.  Since a vitamin B12 deficiency and a folate deficiency both can result in megaloblastic anemia, there is the risk of prescribing folate to a patient with a B12 deficiency.  This can cause irreversible neurological damage, hence the need to create an UL for folic acid (

Vitamin B12:

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Vitamin B12 helps synthesize DNA and maintain healthy nerve cells ( and is found in mollusks, meat, milk, and eggs.  The RDAs for vitamin B12 are 2.4 μg/day for men and women, adolescents and adults.  Cyanobalamin, found in 5-Hour Energy, is the most common supplemental form of this vitamin.  There is no set tolerable upper intake level for vitamin B12 because only a small amount of the vitamin can be absorbed when taken orally (   In the meta-analysis, “Vitamin B12 for Cognition”, Malouf and Sastre (2003) produce a review with the Cochrane Collaboration similar to that which Malouf created for Vitamin B6.  The authors conclude that “no evidence of the efficacy of vitamin B12 of cognitive function” was ascertained in the selected studies (Malouf & Sastre, 2003). 

            In the article, “Vitamin B6, B12, and Folic Acid Supplementation and Cognitive Function”, Balk et al. (2007) present a systematic review of fourteen randomized trials.  Literature searches yielded 6,914 citations, from which 202 were looked at, and then only 14 qualified for their review.  For vitamin B6, sample sizes ranged from 19 to 88 participants, and doses ranged from 12 to 75 mg/day.  Nine different cognitive function subtests were used, and only in one long-term memory test was there an improvement attributed to the vitamin.  For the six trials that looked at the effects of vitamin B12, treatment ranged from 0.01 mg/day orally to 1 mg/weekly intramuscularly for 4 weeks to 6 months.  Three of thirty-five cognitive tests demonstrated a significant result due to vitamin B12.  In the studies looking at folic acid, Balk et al. (2007) concluded that three studies were of “moderate to poor quality”, and that “Overall, 5 tests found a net improvement and 3 a net worsening of cognitive function” (Balk et. Al, 2007, page 26).  However, they did find that in people with low baseline folate levels, supplementation did produce a significant effect.  Balk et al. (2007) also looked at six “Combined B Vitamin” tests.  However, results from this portion of the review mimicked that of the vitamins separately: “For most of the cognitive tests, no effect was found with B vitamin treatment” (Balk et al., 2007, page 28).  From this analysis, Balk et. al (2007) concluded that “the few available randomized controlled trials of vitamins B6, B12 and folic acid supplementation, alone or in combinations, do not provide adequate evidence for a beneficial effect of supplementation on cognitive function testing in people with either normal or impaired cognitive function, although 1 very small trial found an improvement with folic acid supplementation in patients with low baseline folate levels” (Balk et. al, 2007, page 29).  This study is significant in the discussion of 5-Hour Energy because it highlights the discrepancy between the advertising claims of 5-Hour Energy and the assertions that researchers are willing to make at this time about the efficacy of B vitamin supplementation.                                                                                



Compared to the B vitamins, considerably less research has been done on the effects of amino acid supplementation in healthy adults.  For this reason, I am highlighting only two of the ingredients in 5-Hour Energy’s “Energy Blend” (taurine and caffeine). Although the individual amounts of taurine and caffeine in the drink are not disclosed, because of their abundance in other energy drinks, looking at these two compounds makes for a nice comparison of 5-Hour Energy and other brands.


Taurine is an amino acid that supports neurological development and helps regulate blood concentrations  (  There have been claims that taurine helps athletic performance, but studies have shown contradicting reports. Up to 3,000 mg/day of taurine is considered harmless because extra taurine is excreted by the kidneys.  In an experiment conducted by Warburton, Bersellini and Sweeney (2001), they attempted to evaluate whether caffeine and taurine (when taken together, such as in an energy drink), contribute to differences in mood, memory, and information processing, or if it is rather the caffeine withdrawal that usually presents symptoms of enhanced attention in research studies.  Forty-two healthy participants were randomly assigned into the placebo groups (either sugar or sugar-free to control for the effects of sugar on the results) or into the caffeine/taurine group.  The taurine-containing drink also contained sugars, glucuronolactone (an ingredient in 5-Hour Energy as well), and vitamins.   The concentration of caffeine in the beverage was 80 mg/250 ml, about as much as is in a normal cup of coffee (and supposedly near the amount in 5-Hour Energy).  The participants were given a number of cognitive tests, including: “a rapid visual information test, a verbal reasoning test, a verbal and non-verbal memory test, and a set of mood measures” (Warburton et al., 2001).  Two studies were established so that the effects of caffeine and caffeine withdrawal could be compared.  The researchers found that in both studies, the caffeinated/taurine group had improved attention and verbal reasoning, but there was no significant effect on memory. 


One of the reasons why many energy drinks have raised health concerns in the public is due to their high levels of caffeine.  In a review of caffeinated energy drinks, Chad Reissig and colleagues (2008) wrote that, “In 2006, annual worldwide energy drink consumption increased 17% from the previous year to 906 million gallons, with Thailand leading the world in energy drink consumption per person, but the U.S. leading the world in total volume sales”  (Reissig et al., 2008).  The researchers presented a comparison of the caffeine content of many common brands and found that caffeine contents ranged from 50 mg to 505 mg per bottle (a 6-ounce cup of coffee usually contains between 77 to 150 mg (Reissig et al., 2008)).  In table 1 of their article, the researchers accumulated information on various brands of energy drinks from their manufacturers and product labels and determined the relative concentrations of caffeine in different sized products. “Ammo”, a 1-ounce drink has the greatest caffeine concentration of 171 mg/oz, and Coca-Cola Classic has the least concentration of caffeine (2.9 mg/oz).  Red Bull, for comparison, has 9.6 mg caffeine/oz.  

            When I telephoned Living Essentials (the company that produces 5-Hour Energy), a spokesperson said that they could not disclose the specific amount of caffeine in their beverage.  However, they did say that it was equivalent to an average cup of coffee.  Because the warning on the label restricts consumption to two “shots” a day, spaced hours apart, this means that there is less of a risk in someone presenting symptoms of caffeine toxicity when properly using 5-Hour Energy instead of some other energy drinks as their only caffeine source.  The problem, as the Reissig et al. (2008) analysis points out, is that since the FDA does not tightly regulate these products, many consumers do not know the various levels of caffeine in these “dietary supplements”.  This makes it easy to accidently overdose on caffeine, as well as makes children and those with low tolerance for caffeine extremely vulnerable for caffeine toxicity.


5-Hour Energy claims to provide hours of alertness, focus, and increased energy as a result of a unique combination of vitamins and amino acids.  However, the most recent research on the efficacy of these ingredients as supplements to a healthy diet is inconclusive.  5-Hour Energy also claims that it is “good for you”, especially when compared to other drinks with high contents of caffeine and sugar.  Although drinking the recommended dose of 5-Hour Energy probably will not harm you, it is doubtful that it would have positive healthful effects.  Other energy drinks may be worse for you and dangerous, but they also may be more effective for their suggested purpose of increased, rapid energy as a result of high levels of sugar and caffeine.  After trying 5-Hour Energy, I believe that a better recommendation for a long-lasting energy fix would be a peanut butter sandwich and a small glass of orange juice.  With high levels of protein and carbohydrates, this snack could effectively address the claims of the 5-Hour Energy product in a natural way without having to worry about the inclusion of uncertain quantities of caffeine and other potentially harmful substances.






Balk, E.M., Raman, G., Tatsioni, A., Chung, M., Lau, J., Rosenberg, I. H.  (2007).  Vitamin B6,

            B12, and folic acid supplementation and cognitive function: a systematic review of

            randomized trails.  Archive of Internal Medicine 167(1): 21-30

Food and Nutrition Board, Institute of Medicine. Folic Acid, Vitamin B6,,Vitamin B12, Niacin.

            Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Vitamin B12,

            Pantothenic Acid, Biotin, and Choline. Washington D.C.: National Academies Press;


Malouf, R., & Evans, J. (2003).  Vitamin B6 for Cognition.  Cochrane Database of Systematic


Malouf, R., & Sastre, A. (2003).  Vitamin B12 for Cognition.  Cochrane Database of Systematic


Reissig, C. J., Strain, E.C., Griffiths, R.R. (2008).  Caffeinated energy drinks—A growing

            problem.  Drug and Alcohol Dependence (E –published ahead of print).

Warburton, D.M., Bersellini, E., Sweeney, E. (2001).  An evaluation of a caffeinated taurine

            drink on mood, memory and information processing in healthy volunteers without

            caffeine abstinence.  Psychopharmacology 158: 322-328.




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