At some point, we've all had one drink too many. But if you like your cocktails with a caffeine kick, you could be unintentionally drinking more.
A new study out of Australian National University found that while alcohol is a depressant, adding sweetened caffeinated energy drinks "tends to bring out the stimulant effects" of being drunk. "It may be this that causes energy drinks to increase the desire to keep drinking alcohol," says co-author Rebecca McKetin.
The study involved 75 participants between the ages of 18 and 30, who were assigned to drink either vodka mixed with soda water or vodka mixed with a popular energy drink. The subjects answered a series of questions before they drank their cocktail and again 20 minutes afterward.
Those who got the energy drink-spiked cocktails reported a greater urge to keep drinking, and liked their drinks more than those who drank the cocktail of vodka and soda water. The researchers couldn't confirm whether the sweetness or caffeine content of the energy drink was responsible for the effect.