5-hour Energy


What should you do if you feel tired? Taking a nap isn’t always possible. The ever-inventive capitalist marketplace has come up with another option.

5-hour Energy is a flavored energy drink sold as 2 oz “shots.” It was invented by Innovation Ventures in 2004. It is intended to counteract the afternoon slump, to increase alertness and energy, to help you stay sharp, improve attention, leave grogginess behind and sail through your day.


According to the label, its ingredients are:

  • Niacin 30 mg — 150% of the RDA
  • Vitamin B6 40 mg — 2000% of the RDA
  • Folic acid 400 mg — 100% of the RDA
  • Vitamin B12 500 mcg — 8333% of the RDA
  • Energy blend: taurine, glucuronic acid, malic acid, N-acetyl L tyrosine, L-phenylalanine, caffeine, and citicoline. Total amount of blend: 1870 mg. The caffeine content is not specified on the label, but it is supposedly comparable to a cup of the leading premium coffee.

It contains only 4 calories, with no sugar.

A profitable business

Its taste has been compared to “chalky cough syrup,” but astute marketing has cornered 90% of the market and made millions if not billions for the company and its CEO, Manoj Bhargava, a mysterious entrepreneur who avoids the limelight. His paper trail consists primarily of 90 lawsuits.

Possible harms

The company warns that users may experience an uncomfortable niacin flush, that it should be avoided by people with phenylketonuria (PKU), by women who are pregnant or nursing, and by children under 12; and that large amounts of caffeine can be problematic for some people. The 8,333% of RDA of vitamin B12 might seem alarming but is probably safe, since there is little or no toxicity from high doses of B12; but one wonders why they chose to put so much in the product.

There has already been one lawsuit alleging that the product triggered a heart attack and that without the deceptive label the victim would not have used it. The case was voluntarily dismissed. There is a case report of an adolescent experiencing his first-ever seizure after consuming 5-hour Energy. There’s another report of a woman who damaged her liver and ended up in the hospital because she exceeded the dose recommended on the label.

Does it work better than caffeine alone?

Consumer Reports reported on 5-hour Energy. They had access to an unpublished double-blind study furnished by the company. I couldn’t find that study, but I did find a study where they compared 5-hour Energy to the vehicle alone, and not surprisingly the mixture containing caffeine was superior to the version with no active ingredients. Of course caffeine works better than no caffeine; the question is whether 5-hour Energy works better than caffeine alone. As far as I could determine, that has never been tested. Consumer Reportsconcluded that:

5-Hour Energy will probably chase away grogginess at least as well as a cup of coffee.

I think they got it just about right.

What do the other ingredients do?

  • Their claims for B vitamins amount to vague support claims, like “niacin is important for energy production.” There is no evidence that B vitamins would increase energy levels unless the user was suffering from a clinically-significant B vitamin deficiency.
  • They claim that citicholine plays a role in neurotransmission and can help support brain function. Citicholine has been used for Alzheimer’s disease, dementia, head trauma, and thinking problems related to circulation problems in the brain, but there’s no evidence that it benefits healthy people who are tired.
  • They claim that tyrosine transmits nerve impulses to the brain. Yeah, so what?
  • They claim that phenylalanine enhances alertness, but I couldn’t find any studies in PubMed to support that claim.
  • They say that taurine plays a role in digestion and maintains the integrity of cell membranes. Yeah, so what?
  • For malic acid, they only say the body synthesizes it in the process of converting carbohydrates into energy. Yeah, so what?
  • They claim that glucuronolactone has been shown to reduce sleepiness, but the only study I could find tested it in an energy drink that also contained caffeine.

The majority of these claims had an asterisk to a footnote with the usual disclaimer: “* This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.”

How did they choose this mixture of ingredients?

I asked the company that question and did not get a response. There doesn’t seem to be any rationale for anything but the caffeine, and certainly no rationale for the specific amounts of each ingredient.

There is a small study suggesting that L-ornithine supplements might benefit people with physical fatigue, but that’s not in the 5-hour Energy formulation. Why not?

I can only guess that the formula was not created by rational design, but was brainstormed by non-scientists looking for anything they could add to caffeine that might impress the naïve consumer and help sell their product.

Why I’m not going to buy it

  • If you are getting tired during the day, instead of counteracting the fatigue with drugs it would be more useful to look for underlying causes: for instance, it might mean you are not getting enough sleep at night.
  • A nap or exercise might be a better choice than caffeine.
  • Coffee tastes good and the warmth is satisfying: I wouldn’t want to give up my pleasure. Sitting down with a cuppa to rest and change gears appeals far more to me than chugging a quick shot of an energy drink.
  • Coffee contains a lot of antioxidants and is thought to have health benefits that caffeine alone doesn’t. /li>
  • Just on general principles, it seems prudent to avoid high doses of unnecessary ingredients, especially when the particular mix of ingredients has never been properly tested for safety.

Why others might rationally choose to buy it

It’s a source of caffeine that is convenient to carry and to use and does not involve large amounts of liquid or calories. The other ingredients are unnecessary but probably not harmful. It costs less than a cup of Starbucks coffee.

“Try it for yourself”

I was urged to try it, but I’m going to pass. Trying something to see if it works for you sounds intuitively reasonable, but the history of science has taught us otherwise. Personal experience is often misleading and it contaminates our ability to judge something objectively.

This article was originally published in the Science-Based Medicine blog.

Dr. Hall is a contributing editor to both Skeptic magazine and the Skeptical Inquirer. She is a weekly contributor to the Science-Based Medicine Blog and is one of its editors. She has also contributed to Quackwatch and to a number of other respected journals and publications. She is the author of Women Aren’t Supposed to Fly: The Memoirs of a Female Flight Surgeon and co-author of the textbook, Consumer Health: A Guide to Intelligent Decisions.

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