The popularity of energy drinks continues to rise. Many people turn to these caffeine and sugar-spiked beverages to boost flagging energy reserves. But medical experts remain divided about the pros and cons of downing drinks like “Red Bull” and “Rock Star.” This health e-letter will try to present both sides of the argument based on results from two recent studies.
First, the pros. In one clinical trial, researchers presented a problem: acute stress is associated with changes in cognitive performance and mood and these changes are partly the result of an increased release of cortisol. Cortisol is a hormone released by your adrenal gland. Both glucose and caffeine consumed in isolation have been shown to moderate cortisol response and exert a beneficial effect on cognitive performance and mood. But, the researchers said, there has been very little research into the behavioral and physiological effects when caffeine and sugar are taken in combination. So they devised a study to assess the effect of the two substances in combination (under stressful and physically demanding conditions) on cognition, mood and cortisol release. What was the stressful and demanding situation they choose? Fire-fighting training.
Eighty-one participants were administered a 330-ml drink containing either 50 g glucose and 40 mg caffeine or 10.25 g of fructose/glucose and 80 mg caffeine, or a placebo drink. The participants were then tested across a range of cognitive tasks, mood and physiological measures.
The researchers found that there was an increase in grip strength amongst the fire-fighting trainees. The would-be fire fighters also showed improved memory performance after ingestion of the drink containing 50 g of glucose and 40 mg of caffeine, and both active drinks resulted in improved performance on the information-processing task tests compared to placebo. In terms of mood effects, the drink containing 50 g of glucose and 40 of mg caffeine led to a reduction in anxiety and significantly reduced levels of stress following the fire-fighter training. The researchers concluded that, in situations of stress combined with physical performance, administration of an energy drink containing glucose and caffeine might be an easy-to-implement and cost-effective way to maintain mental performance levels and to lessen the negative effects of stress on mood.
Now for the cons: the consumption of alcohol mixed with energy drinks has become a popular and controversial practice among young people. UK researchers devised a study to examine if the consumption of energy drinks alters cognitive processing and subjective measures of intoxication compared with the consumption of alcohol alone.
Eighteen participants (nine men and nine women) attended four test sessions where they received one of four doses in random order (an energy drink or a placebo beverage). The researchers then used standard tests to rate cognitive performance. They found that alcohol slowed task information processing and impaired simple and complex motor coordination. The co-administration of the energy drink with alcohol did not alter the alcohol-induced impairment on these objective measures. For subjective effects, alcohol increased various ratings of feelings of intoxication. More importantly, co-administration of the energy drink with alcohol reduced perceptions of mental fatigue and enhanced feelings of stimulation compared to alcohol alone. In conclusion, the researchers stated that energy drinks and alcohol together may contribute to a high-risk scenario for a drinker.
For a healthy drink, read the article Drink for Your Health and Happiness