Energy Drinks

Energy drinks are beverages whose producers advertise that they "boost energy". These advertisements usually do not emphasize energy derived from the sugar and caffeine they contain but rather increased energy release due to a variety of stimulants and vitamins.

Ingredients :

Energy drinks generally contain methylxanthines (including caffeine), B vitamins, and herbs. Other commonly used ingredients are carbonated water, guarana, yerba mate, açaí, and taurine, plus various forms of ginseng, maltodextrin, inositol, carnitine, creatine, glucuronolactone, and ginkgo biloba. Some contain high levels of sugar, and many brands offer artificially sweetened 'diet' versions. A common ingredient in most energy drinks is caffeine (often in the form of guarana or yerba mate). Caffeine is the stimulant that is found in coffee and tea. Energy drinks contain about three times the amount of caffeine as cola. 12 ounces of Coca-Cola Classic contains 35 mg of caffeine, whereas an Energy Drink contains 120 mg of caffeine.

Energy shots :

Energy shots are a specialized kind of energy drink. Whereas most energy drinks are generally sold in cans or bottles, energy shots are usually sold in 50ml bottles. Energy shots can contain the same total amount of caffeine, vitamins or other functional ingredients as their larger siblings, and therefore they may be considered concentrated forms of energy drinks. The marketing of energy shots generally focuses on their convenience and availability as a low-calorie "instant" energy drink that can be taken in one swallow (or "shot"), as opposed to energy drinks that encourage users to drink an entire can (which may contain 250 calories or more).

Effects :

A variety of physiological and psychological effects have been attributed to energy drinks and their ingredients. Two studies reported significant improvements in mental and cognitive performances as well as increased subjective alertness.



Excess consumption of energy drinks may induce mild to moderate euphoria primarily caused by stimulant properties of caffeine and may also induce agitation, anxiety, irritability and insomnia.  During repeated cycling tests in young healthy adults an energy drink significantly increased upper body muscle endurance. It has been suggested that reversal of caffeine withdrawal is a major component of the effects of caffeine on mood and performance.

Restorative properties were shown by a combination of caffeine and the sugar glucose in an energy drink, and some degree of synergy between the cognition-modulating effects of glucose and caffeine was also suggested. In one experiment, a glucose-based energy drink (containing caffeine, taurine and glucuronolactone) was given to eleven tired participants being tested in a driving simulator. Lane drifting and reaction times were measured for two hours post-treatment and showed significant improvement.
 Caution is warranted even for healthy adults who choose to consume energy drinks. Consumption of a single energy drink will not lead to excessive caffeine intake; however, consumption of two or more drinks in a single day, can. Other stimulants such as ginseng are often added to energy drinks and may enhance the effects of caffeine, and ingredients such as guarana themselves contain caffeine. Adverse effects associated with caffeine consumption in amounts greater than 400 mg include nervousness, irritability, sleeplessness, increased urination, abnormal heart rhythms (arrhythmia), and dyspepsia. Consumption also has been known to cause pupil dilation when taken with certain antidepressants or SSRIs. Most mainstream energy drinks do not provide electrolytes, and have a higher likelihood of an energy "crash-and-burn" effect. Caffeine in energy drinks can excrete water from the body to dilute high concentrations of sugar entering the blood stream, leading to dehydration. If the body is dehydrated by 1%, performance is decreased by up to 10%.

Caffeinated alcoholic energy drinks :

Energy drinks are often used as mixers with alcoholic beverages producing mixed drinks which are similar to but stronger than rum and coke with respect to the amount of caffeine that they contain. They are also sold in a wide variety of formulations which combine caffeine and alcohol. Fruit flavored caffeinated energy drinks in flavors such as watermelon, lemonade and cranberry-lemonade are cheap with a fruity taste. Packaged in 24 ounce cans, they are wildly popular with young people.

Through separate mechanisms, energy drinks act as stimulants and alcohol as depressants. Mixing a depressant with a stimulant sends mixed signals to the nervous system and can cause cardiac problems such as heart arrhythmia. In addition, energy drinks can lessen some of the subjective effects of alcohol while making the drinker feel more stimulated and less fatigued. However, they may be unable to counteract some of the psychomotor impairments of alcohol intoxication. Consequently, the mix can be particularly hazardous as energy drinks can mask the influence of alcohol and a person may misinterpret their actual level of intoxication In fact, people who drink mixers are more likely than non-mixers to drink more alcohol, and are also more likely to suffer alcohol-related consequences such as assault, injury or being an intoxicated driver, even after adjusting for the number of drinks. Although people decide to drink energy drinks with alcohol with the intent of counteracting alcohol intoxication, another large majority do so to hide the taste of alcohol. Researchers at the Human Performance Laboratory have suggested people refrain from mixing such powerful stimulants with alcohol, they believe it might cause cardiopulmonary or cardiovascular failures.  

Anti-energy drinks :

Several beverages have been marketed in the world as "anti-energy", "chill out", or "relaxation" drinks. They are growing in popularity, with sales doubling from 2008 to 2010, and expected to more than double again by 2014. They contain ingredients such as theanine and melatonin.

Hidden risk :

In November 2010, the University of Texas Medical School at Houston reported that energy drinks contain more caffeine than a strong cup of coffee, and that the caffeine combined with other ingredients (sometimes not reported correctly on labels) such as guarana, amino acid taurine, other herbs, vitamins and minerals may interact. Energy drinks consumed with alcohol may affect heart rates, blood pressure and even mental states. The caffeine content of energy drinks range from 80–300 mg per 16-oz serving whereas a 16-oz cup of coffee can contain 70–200 mg.
Health experts say caffeine prevents sleepiness and delays the feeling of drunkenness normally experienced when drinking alcohol, causing some people to continue drinking after they normally would have stopped. Both caffeine and alcohol are diuretics, so mixing energy drinks with alcohol can cause severe dehydration, possibly leading to vomiting, nausea, and other health problems in the long term.