Writing in the Physician and Sportsmedicine, researchers at Nova Southeastern University in Florida reviewed current evidence on the potential benefits of energy drinks.
The drinks are now being promoted not just as energy boosters but as sports beverages but evidence is mixed on their suitability. Assistant professor Stephanie Ballard said: “Most of the performance-enhancing effects of energy drinks can be linked to their caffeine content. Caffeine has been consistently been observed to enhance aerobic performance, although its effects on anaerobic performance may vary.”
Sugar content
Energy drinks are also not simple vehicles for caffeine consumption. In a review on energy drink use and safety for athletes in Physician and Sportsmedicine, scientists said they contain significant quantities of sugar, which could work positively or negatively in pursuit of better sporting performance.
On the upside, the researchers wrote: “The sugars in energy drinks (particularly glucose) may act synergistically to enhance the effects of caffeine. When consumed in sufficient amounts, the sugar may be used as carbohydrates in loading regimens to enhance exercise performance.”
However, high sugar levels and the laxative effect of fructose may cause gastrointestinal distress. In addition, the scientists said: “The high concentration of sugars in energy drinks tends to slow the rate of fluid absorption from the intestine; therefore, it is not ideal to consume energy drinks before or during exercise.”
Weight loss
On the subject of weight loss there is plenty of conflicting evidence, and a lot appears to depend on how and how much energy drinks are consumed.
Ballard said: “Although some data suggest that combining energy drink use with exercise may enhance body fat reduction. Increases in burning calories and losing weight are likely subject to diminishing returns as users become habituated to caffeine.
The scientist added that it is important not to forget that energy drinks are loaded with sugar. “Despite their use for weight loss, energy drinks may be contributing to the obesity epidemic alongside less caffeinated, sugary drinks like soda.”
Source: Physician and Sportsmedicine
Effects of Commercial Energy Drink Consumption on Athletic Performance and Body Composition
Authors: S. Ballard J. Wellborn-Kim, K. Clauson
Source: Physician and Sportsmedicine
Energy Drinks: A Review of Use and Safety for Athletes
Authors: E. Duchan, N. D Patel, and C. Feucht