Energy drinks

Energy drinks are beverages that contain caffeine. Despite their name, energy drinks do not contain any more energy, for example sugar, than any other soft drinks, but they are assumed to be sources of ”energy” due to the compounds that they contain, such as caffeine, taurine, glucuronolactone or taurine. Energy drinks are often also fortified with group B vitamins and inositol.

Compounds added to energy drinks

Caffeine

Caffeine is found in the leaves, seeds or fruits of more than 60 plants. The most well-known of these are coffee, tea, cocoa beans, kola and guarana. The chemical name of caffeine is 1,3,7- trimethylxanthine. Caffeine is consumed in the form of coffee and cola drinks because of its stimulating effect. This effect lasts for a few hours, depending on the amount of caffeine and an individual’s metabolism. Caffeine is added to energy drinks.

There is no recommended intake for caffeine, as it is not an essential nutrient. According to the European Food Safety Authority (EFSA scientific opinion, 2015), a single dose of caffeine for a healthy adult up to 200 mg, and a daily intake up to 400 mg of caffeine does not raise safety concerns.

Adverse effects of excessive caffeine intake include nervousness, restlessness, irritability, difficulty concentrating, heart palpitations, arrhythmias, gastrointestinal discomfort, and reduced tolerance to stress. The effects of caffeine vary greatly between individuals, and people who are sensitive to caffeine may experience symptoms even at low doses.

Taurine

Taurine is a low-molecular-weight amino acid, which is formed in the body as an end product of methionine and cysteine metabolism. No recommended values for intake of taurine from nutrition have been specified. The taurine content of energy drinks varies between 250 mg/l and 4000 mg/l. In its 2009 opinion, EFSA states that even high intakes of taurine are unlikely to cause adverse effects. The opinion sets the highest daily intake of taurine with no observed adverse effects at 1,000 mg per kilogram of body weight, which corresponds to 60 g for a person weighing 60 kg.

Glucuronolactone

The body forms delta-glucurono-gamma-lactone, or glucuronolactone from glucose. The intake of glucuronelactone from energy drinks may be several hundreds of times higher than from nutrition, as the glucuronolactone content of the drinks varies between 2000 mg/l and 2400 mg/l. In its 2009 opinion, EFSA states that large intakes of glucuronolactone apparently would not have adverse effects. According to EFSA the research indicates that the maximum non-adverse daily dose of glucuronolactone is 1,000 mg per kilogram body weight, which corresponds 60 g for a person weighing 60 kg.

Guarana

The short-term effects of guarana are usually based on the high caffeine and tannin levels of the plant. Guarana extract contains 3.5-5% of caffeine. No certain knowledge is available about the effects of the other ingredients. The influence of products that contain guarana is similar to those of caffeine-containing products. The side effects associated with guarana are similar to those of other products that contain caffeine.

Inositol

Inositol is a water-soluble compound that the body synthesizes from glucose. It is classified as a vitamin-like compound, which does not in all respects meet the definition of a vitamin. The inositol content of energy drinks is ca. 20 mg/100 ml. No recommended intake value has been defined for inositol, as it is not an essential nutrient.

Vitamins

The most common vitamins added in energy drinks include vitamins of group B: niacin, vitamin B₆, vitamin B₁₂ and pantothenic acid. Some drinks are fortified also with vitamins C and E, as well as with inositol.

As water-soluble vitamins, the vitamins of group B are not stored in large amounts in the body; excess amounts are mainly excreted through the kidneys in urine. However, vitamin B₁₂ is an exception, as it can be stored in the body. Deficiency of vitamins B is rare, since these vitamins are commonly obtained from basic everyday foods.

A can of energy drink often provides vitamins B in amounts equal to or well above the daily requirement. Of the group of vitamins B, tolerable upper intake levels (UL values) have been established for niacin, vitamin B₆, and folic acid. The UL values indicate the highest amount of vitamin or mineral that most people can consume daily without the risk of adverse health effects. A UL value has also been set for vitamin E.

More information

Caffeine content in beverages and chocolate /package or portion (pdf to print, 78 kb)