The energy drink that could burden the heart: Energy drinks have become in recent years a permanent part of the daily routine of teenagers, students, soldiers, and exercisers. They are found near the cash register, sold on sales, and packaged in language that promises strength, sharpness, focus, and energy. However, unlike coffee, whose effect most consumers know how to evaluate, a can of energy drink is sometimes perceived like a soft drink. This is exactly the problem: The body thinks and behaves differently.
The central component in most of these drinks is caffeine. It blocks the effect of adenosine, a substance in the brain involved in the feeling of fatigue, and thus creates a fast sense of alertness. At the same time, caffeine may raise heart rate and blood pressure, especially in those who are sensitive to it or drink several cans in a row. Some of the drinks also contain guarana, a plant that contains caffeine itself, and sometimes the consumer does not understand that the total dose of the stimulating substance is higher than what appears at first glance on the label.
The risk does not end with caffeine alone. Many energy drinks contain taurine, ginseng, plant extracts, and sugar in a high amount. Not every such component is dangerous on its own, but the combination between them is liable to affect the autonomous nervous system, the blood vessels, and the electrical activity of the heart. In controlled studies among healthy young people, an increase in blood pressure was observed after drinking energy drinks and sometimes a change in the QT interval on the ECG, a index reflecting the period of time in which the heart recovers electrically between beat to beat. In most people, it is a small and passing change, but in people with a tendency to arrhythmia, hidden heart disease, a congenital disorder in the conduction system, or the use of medications that affect the QT interval, even a small change is liable to be more significant.
The particularly worrying combination is an energy drink with physical effort, lack of sleep, dehydration, or alcohol. A young person who goes out to a party drinks several cans with alcohol and continues to dance for hours, puts the body into a state of double load: On one side a stimulating substance that blurs fatigue, and on the other side alcohol that reduces judgment and damages fluid regulation. Also exercisers who sip such a drink before an intense workout are liable to feel a momentary "drive", but pay with an accelerated heart rate, tremor, anxiety, headache, nausea, or difficulty falling asleep at night.
It is important to emphasize: One can once in a while in a healthy person is not equivalent to an immediate life danger. The warning is against the normalization of these drinks as a daily habit, especially in adolescence, among those who suffer from anxiety, sleep disorders, high blood pressure, heart diseases, or taking medications for attention and concentration. Also pregnant women, children, and teenagers need to be especially careful of high caffeine consumption.
Whoever is looking for alertness ahead of an exam, driving, or a workout needs to start with the base: Sleep, drinking water, a light meal, and load planning. Regular coffee in a known and clear measure is preferable in most cases to a can that contains a mixture of stimulants and sugar. In gyms and in schools it is worthwhile to say the simple truth: Real energy does not come from a tempting can. It starts in a body that is not dragged time and again into an emergency state.
Dr. Itay Gal is a specialist in pediatrics, a sports and aviation physician, and the medical commentator of Maariv. For more articles click here