A good energy drink can do more than just keep you awake. The right dose of caffeine, B-vitamins, and other ergogenic and nootropic compounds can give you a huge boost both to physical performance (think endurance, strength, and muscular power) and mental performance, in the form of better focus and concentration.
Looking to optimize energy drink usage in your routine? Here’s what our research team uncovered when digging through the science of energy drinks
1. A good energy drink provides caffeine alongside ergogenic and nootropic compounds.
The most common among these extra ingredients are B vitamins, taurine, green tea extract, and herbal extracts like yerba mate extract and guarana.
Energy drinks rocketed to popularity after an obscure local drink in Thailand was reformulated and marketed to a global audience.
That drink, of course, was Red Bull, which is a market-dominating juggernaut among energy drinks.
More recently, competition has gotten fierce among companies vying for a share of the market.
There are varying levels of evidence that each of these can enhance your energy levels
2. Caffeine has the biggest role when it comes to boosting energy
Caffeine is a stimulant, meaning it kick-starts your metabolism, increases your alertness, improve your reaction time, and increase your physical performance during exercise.
The amount of caffeine you consume is related to the strength of these effects, but as always, there can be too much of a good thing!
3. Taurine is another staple ingredient of energy drinks, but it might not be a very important one
It derives its name from the fact that it was first isolated in the liver bile of oxen in the 1800s, but it’s far more common in your body than you’d think. It plays a critical role in the development of the nervous system and ensuring its proper function.
By including taurine in energy drinks alongside caffeine, the hope is that the energy drink will elevate your nervous system to a higher performing level than with caffeine or taurine alone.
A highly detailed study published in 2012 attempted to tease out how caffeine and taurine interact to produce the reported benefits of energy drinks (1).
As expected, caffeine had a consistent and significant beneficial effect on tasks like short term memory and reaction time. Taurine had some beneficial effects too, but even when combined with caffeine, it contributed only in a small, varied, and unpredictable way to cognitive performance.
4. B vitamins could help improve the function of your central nervous system
These play a key role in the functioning of your nervous system too. Like with taurine, the hope is that the B vitamins will interact synergistically with the caffeine to boost your energy levels and alertness to a higher level than possible with just caffeine.
One study published in 2012 in the journal Nutrition & Metabolism found that a pre-workout supplement that combined caffeine and B-vitamins, along with a few other ingredients, did boost performance on agility and lower body muscular endurance during an exercise testing session (2).
However, it did not evaluate the role of each ingredient individually—it was compared against a true placebo, not a caffeine-only supplement.
5. B-complex vitamins could elevate physical and mental stamina
A range of B-vitamins are commonly included in energy drinks alongside the caffeine, taurine, sugar, and other popular ingredients.
Do these B-vitamins make a difference? Some research suggests that they do. A paper published in the journal Human Psychopharmacology tested the effects of a high-dose B-complex vitamin on self-reported physical stamina, mental stamina, and concentration levels over the course of a four-week study (3).
The researchers found that B-complex vitamin supplement was able to elevate both physical and mental stamina, as well as increase concentration.
Perception is everything when it comes to productivity, so this study provides strong evidence that the B vitamins play an important role in the performance boosting and mood elevating mechanisms of an energy drink.
Energy drink side effects
Like with many biologically active compounds, there are drawbacks to consuming too much of several of the compounds in energy drinks. The two you need to be most concerned about are caffeine and niacin (vitamin B3).
Caffeine can cause jitters and an elevated heart rate when taken to excess. Caffeine is, of course, a stimulant, and in high doses, it can have deleterious effects on your body: jitters, a racing heartbeat, and nausea are some common side effects of consuming too much caffeine.
In rare cases, high doses of caffeine from energy drinks have caused abnormal heart rhythms, which can sometimes even lead to death, as described in a case study published in 2013 by doctors in Turkey (4).
Too high a dose of an energy drink does not pair well with exercise. Medical reports caution that overuse of energy drinks, especially when combined with aggressive, strenuous physical activity, can cause heart problems even in young, healthy people (5).
Most people should keep daily caffeine intake below 400 mg per day. According to the Mayo Clinic, most people can handle up to 400 mg of caffeine per day (6). Many people, of course, consume more than this, and it’s likely that there is a wide range in individual tolerance, but this guideline is a good place to start.
Some energy drinks can cause flushing and tingling. Niacin, also known as vitamin B3, is also known to cause some problems when consumed to excess. Doses of 35 mg or more are known to cause flushing, redness, itchiness, and a tingling sensation (7).
Some energy drinks come very close to this amount of niacin, so to avoid this, you shouldn’t take any other supplements with niacin in them, or consume more than one energy drink per day if it has a lot of niacin.
Energy drink dosage
Though energy drinks seem like a food or drink, it’s important to remember they’re really more like a supplement. Too much can cause problems for your health and well-being.
In most cases, you shouldn’t drink more than two energy drinks per day. It depends somewhat on the brand—drinks with lower caffeine contents and lower amounts of niacin are safer to consume more often, but a highly caffeinated or niacin-rich drink consumed more than twice daily could cause problems (even with products in our rankings, which we ensured have reasonable amounts of caffeine).
Energy drinks are formulated in a “pre-made” dose; they’re already calibrated for what you need. Usually, just one should do the trick!
Energy drink benefits FAQ
Q: Are energy drinks bad for your health?
A: Too much of just about anything can be bad for your health, and energy drinks are no exception. In rare cases, consuming enormous amounts of highly caffeinated energy drinks has led to dangerous heart arrhythmias and in a few cases, death from cardiac arrest.
These cases usually involve consuming a dozen or more energy drinks in a day. Beyond caffeine, niacin in excess can cause some short-term negative side effects including flushing, itching, and redness.
A few energy drinks get close to the daily intake limits of niacin, including, for example, 30 mg of niacin when the daily intake limit recommended by the Food and Drug Administration is 35 mg.
Q: What is bad about sugary energy drinks?
A: Perhaps the most serious but mundane health risk for energy drinks comes from their sugar content.
A 16 ounce can of some brands of energy drinks can contain upwards of 50 grams of added sugar, which is approximately double the total amount of added sugar intake per day recommended by the American Heart Association.
Too much sugar, as you likely know, can lead to obesity, type two diabetes, and an increased risk for heart disease.
Q: How long does an energy drink last?
A: The duration of the effects of an energy drink, or how much “energy” it gives you, colloquially, will depend mostly on its caffeine content, since its half-life is the shortest among major energy drink ingredients.
Since 50% of the caffeine in an energy drink is eliminated within five hours of consuming an energy drink, and because it takes about 80-100 mg of caffeine to have a significant performance boost on your body, some quick math shows that a typical energy drink with about 200 mg of caffeine should last for five to seven hours.
Something with less caffeine will necessarily last shorter, only a few hours in the case of a 100 mg caffeine energy drink.
Notably, other benefits of energy drinks like appetite suppression and mood elevation, may not last as long—most of the scientific research has been focused on the effects of energy drinks on objective measures of performance, and less has studied the time course of mood changes and similar subjective (though still important) effects.
Related: Our best energy drink picks
Need to boost your physical and mental performance, or sustain performance in difficult environments? A solid energy drink with the right dose of caffeine, B-vitamins, and other nootropics is the way to go.
When used correctly, energy drinks have proven benefits in aiding everything from endurance performance to concentration levels and mood. They’re a great tool to have at your disposal, whether you need a physical or cognitive boost.