Food for thought: Energy drinks in Turkey, Uruguay and Denmark are banned from consumption. Studies across the world have proved that consuming a large amount of caffeine- the core ingredient of energy drinks, results in increased heart rate and blood pressure, interrupted sleep, nervousness and irritability. The Food Safety and Standard Authority of India (FSSAI), which recently ordered a few brands off the shelf says that the name itself is a misnomer as there is no case for encouraging their consumption. But there's a catch. You are unlikely to die from a single can of an energy drink but to avoid experiencing these symptoms (or caffeine intoxication, caffeine-induced anxiety and sleep disorders), you have to know what's causing the harm.
Is there an average safe dose of caffeine?
Ever observed how that guy sitting next to your cabin gets jittery after just a cup of cappuccino? That's because some people are more sensitive to caffeine. "Even at amounts less than 100mg, people who are hypersensitive to caffeine can experience overdose symptoms such as insomnia, jitters, and an increased heart beat," says Dr V Sudershan Rao, a scientist and deputy director, National Institute of Nutrition, Hyderabad. And that sensitivity depends on a variety of factor like age, gender, medication use, anxiety disorders, food habits and activity levels and also genetics. Though there is no separate regulation for energy drinks, carbonated beverages are not supposed to breach the144ppm caffeine limit. But the majority, says Dr Rao, can usually have 200-400 mg of caffeine daily without any adverse reactions. The answer to the question whether anybody can create an average safe dose is not as simple. Our bodies essentially recognise substances like alcohol and caffeine as harmful and once they do, they metabolise them with the help of enzymes in the kidney or flushes it out. But once the threshold of the substance is crossed, then the entire amount reaches the vital organs, leading to over excitement and eventually becoming toxic. "Everything can be toxic to the body but it all depends on the level," says Dr Prathap Kumar Shetty H, President, Association of Food Scientists and Technologists, India.
Who's the culprit?
Energy drinks are not the so called "bad products", opines Shetty. Essentially non-alcoholic beverages containing caffeine, guarana, glucuronolactone, taurine, ginseng, inositol, carnitine, B-vitamins etc., these are the main ingredients that act as stimulants says FSSAI. "FSSAI has set the safe limit at 400mg and a 100ml can gives you 32mg. So to consume 400mg, one has to consume more than 12 cans of 100 ml, even then he will be only be crossing the safe limit and not the toxic level," says Shetty. That's not to deny that if consumed in large amounts, especially over extended periods of time, caffeine can lead to caffeinism, which usually combines caffeine dependency with a wide range of unpleasant physical and mental conditions, according to FSSAI.
What gives you the boost?
Taurine, a naturally occurring amino acid in humans is one of the key ingredients which seems to improve performance. In a widely reported Scottish study, 1,000 milligrams of taurine taken as a supplement appeared to improve the performance of middle-distance runners. But it is said that there wasn't anything conclusive about the role taurine played. "Theoretically, taurine is not considered to be toxic and excess taurine is usually flushed out through the kidneys. But studies have reported side effects such as declining of heart rate and increase in arterial blood pressure," says Dr Anoop Misra, Chairman, Fortis-C-DOC Centre of Excellence for Diabetes, Metabolic Diseases. And it is even harder to say whether the side effects are because of excess caffeine, taurine or a combination of both, he says.
Another key ingredient of energy drinks, Glucuronolactone is a naturally occurring chemical which is an important structural component of nearly all connective tissues. It is also said to increase performance levels. In a widely reported study by Dr Crag A Goodman, University of Wisconsin, when he injected lab rats with the same, it was found that they swam better. Glucuronolactone is supposed to have a detoxifying effect on the body. So during intensive workouts, this chemical helps the body to perform better by reducing the accumulation of toxic substances, Shetty explains.
Know your caffeine metabolism
Until validated by actual lab tests, it is hard to recommend how much caffeine one can consume on a daily basis, but you can find out the rate at which your liver breaks caffeine down, or caffeine metabolism by genetic tests.
"Caffeine sensitivity differs for each individual, depending on which variation of CYP1A2 you have. CYP1A2 governs the rate of clearance of caffeine from the body, mediated by liver. Variations in such genes make your body processes and eliminate the caffeine from your bloodstream fast or slow, enabling your caffeine metabolism accordingly, says Dr Amol Raut, CEO, GeneSupport, a nutrigenomics lab in Pune. Though genetics in not the only factor involved, nutrigenomics, the study of how food affects our genes and how genetics affects how we respond to nutrients, can give us a "bigger picture on the basis of which you can know whether you should be restricting your intake of caffeine or not."