A new U.S. Army study warns service members to consume energy drinks in moderation, citing them as a cause of sleep problems among those on combat deployment.
Researchers looked at service members deployed in Afghanistan in 2010. A random survey of U.S. Army and Marine combat troops there revealed that 45 percent consumed one or more energy drinks per day and 14 percent consumed three or more.
Some energy drink brands contain the caffeine equivalent of three cups of coffee. Ironically, these drinks, which are advertised to boost energy, can cause daytime sleepiness and impair performance when consumed in excess, the study found.
According to the study, 38 percent of service members consuming three or more energy drinks per day averaged four hours or less of sleep each night -- as opposed to 18 percent of those drinking one to two per day and 24 percent for those consuming no energy drinks.
Service members consuming three or more energy drinks per day were also more likely to report sleep disruptions related to stress or illness. And members of this group were more likely to fall asleep during briefings or on guard duty, researchers said.
While the study did not find a correlation between energy drink consumption and accident rates due to sleepiness, the study's authors recommend service members should be informed about "the potential adverse effects of excessive energy drink consumption on sleep and mission performance and should be encouraged to moderate their energy drink consumption in combat environments."
According to the study, combat troops are far more likely to consume at least one energy drink per day (45 percent) than the overall U.S. adolescent and young adult male population (6 percent).
The study was conducted by researchers at Walter Reed Army Institute of Research using data collected by Joint Mental Health Advisory Team 7 (J-MHAT 7), which observed U.S. troops serving in Operation Enduring Freedom in Afghanistan during 2010.
Although Mental Health Advisory Teams routinely conduct surveys to monitor the well-being of U.S. troops, this was the first study to inquire about their use of energy drinks.