Most of these drinks have about the same amount of caffeine as a cup of strong instant coffee (see the Table for details). It’s added as:
- Brewed coffee,
- Guarana (another caffeine-containing plant product) or as
- The straight chemical (which is obtained commercially as a by-product of the manufacture of decaffeinated coffee).
Energy drinks (or ‘formulated caffeinated beverages’, as they’re called in the Food Standards Code) display a warning on the label indicating that they’re not recommended for children, pregnant or lactating women, or people sensitive to caffeine. But there are caffeine-containing drinks that don’t carry it because they’re not strictly ‘formulated caffeinated beverages’: for example, K-FEE Turbodrink is just coffee, while COCA-COLA and PEPSI contain caffeine, but not enough to qualify.
Most energy drinks contain sugar, either as ordinary table sugar (sucrose) or glucose. Sugar is rapidly digested and absorbed into the body, so the kilojoules of energy it provides are quickly made available for physical exertion. However, most of us not exerting ourselves physically would be better off without these additional kilojoules. You wouldn’t stir about 12 teaspoons of sugar into your tea or coffee, but that’s what’s in a can of RED EYE Classic.
Two of the drinks have no sugar: RED BULL Sugar Free and V Sugarfree Invigoration Guarana Energy — they have artificial sweeteners instead.
Most of these drinks have taurine as a key ingredient. We checked out the science and asked the manufacturers about its inclusion, but we’ve yet to see any convincing evidence that it’ll give you a buzz. Taurine’s used by the body in a wide range of protective and metabolic activities, but exactly what it does (and how it does it) is still largely unknown.
Whatever its merits, though, you don’t need to buy it in a can because there’s plenty in the usual Australian diet and your body can easily make enough of its own — unless, perhaps, you’re an elite athlete.
There’s only limited evidence that taurine is safe at the very high levels found in some of these drinks. Under the Food Standards Code it’s allowed in energy drinks at levels that’ll give you a maximum intake of up to 2000 mg per day, as long as you don’t exceed the recommended number of cans in a day. It’s also allowed in sports foods, but curiously only to levels that’ll give you no more than 60 mg per day. With so little known about it, we think it’s crazy to allow such high levels of taurine in drinks that are often consumed by kids.
NAUGHTY GIRL contains carnitine rather than taurine. According to NAUGHTY GIRL it “assists fat burning”. But like most such claims it’s probably too good to be true — we looked for evidence and remain unconvinced.
B vitamins are used by the body in various ways that involve the release of energy from food. There’s no obvious justification for including them in these drinks because a well-balanced diet already provides an adequate intake, and more of a good thing isn’t necessarily better.
There’s good evidence that caffeine enhances sports performance for elite athletes, though not for the average athlete. And energy drinks shouldn’t be confused with sports drinks, which are designed to maximise hydration.
Sports drinks such as POWERADE and STAMINADE typically have about 12 g of sugar per serve, but most energy drinks have more than this (see the Table). A high sugar concentration can slow absorption of water into the body, making these drinks unsuitable for rehydration during prolonged and vigorous physical exercise.