MONDAY, July 30, 2012 (HealthDay News) -- U.S. college students who drink caffeinated energy drinks mixed with alcohol are more likely to have casual sex, which is often risky sex, a new study finds.
Drinks such as Red Bull & vodka, and Jagerbombs (energy drinks combined with a shot of Jagermeister), rank among the best-selling mixed drinks in bars and clubs serving college-age adults, according to background information in the report.
The study, published online in the Journal of Caffeine Research, included about 650 students at a large public university. Their ages ranged from 18 to 40, but more than 60 percent of them were younger than 21.
The University at Buffalo researchers found that more than 29 percent of the sexually active participants said they had consumed alcohol mixed with energy drinks in the previous month.
During their most recent sexual encounter, about 45 percent of the participants had a casual partner, 25 percent were drunk, and 44 percent said they did not use a condom. Those who reported drinking alcohol mixed with energy drinks were more likely to have casual sex and/or to be drunk during their most recent sexual encounter.
However, students who drank alcohol mixed with energy drinks were no less likely than nondrinkers to have used a condom during their most recent sexual encounter.
The findings suggest that alcohol/energy drink mixes may play a role in the "hook-up culture" that exists on many college campuses, according to study author Kathleen E. Miller, a senior research scientist at the University at Buffalo's Research Institute on Addictions, in Buffalo, N.Y.
She noted that having casual sex or sex while intoxicated can lead to problems such as unintended pregnancy, sexually transmitted diseases, sexual assault and depression. Previous research has linked energy drinks with dangerous behaviors such as impaired driving, binge drinking and fighting.
"Mixing energy drinks with alcohol can lead to unintentional overdrinking, because the caffeine makes it harder to assess your own level of intoxication," Miller said in a university news release.
She noted that energy drinks mixed with alcohol "have stronger priming effects than alcohol alone. In other words, they increase the craving for another drink, so that you end up drinking more overall."
The research doesn't prove that drinking energy drinks with alcohol causes drunkenness and promiscuity, Miller said. But she hopes the findings lead to safety legislation or educational campaigns.
The U.S. Centers for Disease Control and Prevention has more about caffeinated alcoholic beverages.