There is no definition of the term “energy drinks” in scientific literature or legislative documents, but they usually contain various combinations and amounts of caffeine, B vitamins, plant extracts, glucuronolactone, inositol, carnitine, creatine, etc. These drinks are designed to support mental and physical activity and reduce signs of fatigue. For example, it has been found that consuming 250 ml per day of an energy drink containing caffeine, ginseng, and guarana stimulates brain activity, memory, and attention, while consuming a drink with a combination of sugars, taurine, and glucuronolactone has an effect on reaction speed during fatigue.
Energy drinks are an active subdivision of the early soft drink industry. For example, Pepsi was originally advertised as an energy drink. The name Coca-Cola comes from its two active ingredients, both known stimulants: coca leaves and kola nuts (a source of caffeine). Coca leaves were replaced with other stimulants in 1904 due to concerns about the use of cocaine in food products. In 1916, a federal lawsuit forced Coca-Cola to reduce the caffeine content of its drink. This turn of events led to the end of the first wave of energy drinks.
A single daily intake of energy drinks is not considered to pose a health risk. When consuming two or more drinks per day, due to the increased intake of caffeine in combination with other ingredients with a stimulating effect, adverse effects on the body are possible: increased nervousness, anxiety, tremors, insomnia, headaches, palpitations, respiratory disorders, changes in the mucous membrane of the gastrointestinal tract, dehydration due to loss of water and salts from the body. Children are a higher risk group because the adverse effects of caffeine occur at much lower doses than in adults. The combined intake of energy drinks with alcohol and/or drugs poses a significant health risk, especially in young people, as the stimulating effect of energy drinks masks the toxic effects of alcohol and drugs. In Europe, energy drinks containing taurine and caffeine have led to deaths among athletes. According to a 2017 study, caffeine content is not the only factor, but the cocktail of other ingredients makes energy drinks more dangerous than other drinks containing only caffeine.