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Energy drinks

Energy drinks have come a long way since the 1920s when they were first introduced in the UK as a drink to aid recovery from illness. Energy drinks are now big business, soaring in popularity over the last decade and often sold with the promise to make you more alert and awake.

Who uses energy drinks?

Although energy drink sales have been increasing, they remain a relatively small part of the overall soft drinks market. The most common age category of consumers is the 18-34 age group. Non-sport energy drinks are heavily marketed towards this group.

What is an energy drink?

Original energy drinks provided calories (usually as sugar) together with other substances implied to boost metabolism, improve mental function or reduce physical fatigue. Functional energy drinks originated in the Far East where market dominance survives today.

Current energy drinks fall into two main categories - neutraceutical drinks (providing additional nutrients and plant extracts claiming to improve mental or physical wellbeing) and sports drinks (claiming to support performance, endurance and recovery from exercise). For the weight-conscious consumer low calorie versions of popular energy drinks are increasingly available.

Most energy drinks provide their active ingredients in far greater amounts than is usually found in the diet.

Are energy drinks effective at what they claim to do?

There's been plenty of research on the impact of taking energy drinks on mental and physical health, sometimes with conflicting results. Overall, energy drinks improve exercise endurance and physical performance for up to 90 minutes after drinking. They have also been shown to improve mental alertness and counteract sleepiness, especially in drivers. This response has been shown to be similar to taking caffeine alone although consumers consider energy drinks to have properties beyond that of a cup of coffee. Research suggests that a high energy drink consumption is associated with more risk-taking behaviour in adolescents.

Energy dinks may contain:


Caffeine rapidly boosts mental alertness and reduces tiredness. These effects are proportional to caffeine dose - the larger the dose, the greater the effect. Most energy drinks contain similar caffeine levels to a mug of coffee- around 80mg - although some energy drinks may provide double this amount.

Caffeine is not a diuretic for most of us accustomed to regular caffeine intake, but has a mild diuretic effect in those unused to caffeinated drinks. For caffeine-sensitive individuals, caffeine can cause headaches, the 'jitters' and insomnia. For this reason caffeinated drinks are best avoided for three to four hours before bed in those with sleep problems.

Yerbe mate, a natural herb, is another rich source of caffeine sometimes used in energy drinks.


Panax ginseng (Korean or Asian ginseng) is rich in ginsenosides, plant substances that can reduce fatigue and help regulate blood glucose levels, although sports research doesn't support a performance enhancing (ergogenic) effect. Siberian ginseng is from a completely different shrub with no ginsenoside activity.

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