Alcohol plus energy drink only masks drunkenness

NEW YORK - People who combine energy drinks with their alcohol may feel more sober than they truly are, a new study suggests.

In experiments with young male volunteers, Brazilian researchers found that the men were no less impaired when they drank a mix of alcohol and the energy drink Red Bull than when they downed a standard mixed drink.

Drinkers did, however, seem to think they were less drunk - reporting less fatigue, fewer headache symptoms and better coordination.

This is concerning because people who mistakenly think they are less impaired can be a danger to themselves and others, according to study co-author Dr. Maria Lucia O. Souza-Formigoni.

"I think people should be aware of this effect of the combination -- they feel better but they are not 'good enough' to drive, for instance," Souza-Formigoni, an associate professor at the Federal University of Sao Paulo, told Reuters Health.

Energy drinks like Red Bull typically consist of carbohydrates, B vitamins, caffeine and taurine, a derivative of an amino acid found in animal tissue. Some studies have shown that the beverages, or their main ingredients, may improve mood and physical performance. And there's a popular, though unproven, belief that mixing energy drinks with alcohol can counter some of the effects of drinking.

The new study, published in the journal Alcoholism: Clinical & Experimental Research, suggests that while energy drinks may help imbibers feel less tipsy, they are still in fact drunk.

The study included 26 young men who each took part in three separate experiments: one in which they drank vodka mixed with Red Bull, another in which they had vodka mixed with fruit juice, and a third where they drank only the energy drink.

In general, the researchers found that the men reported fewer headache symptoms and less weakness with the Red Bull mixture compared with the standard mixed drink. They also thought their hand-eye coordination was sharper.

However, the men performed no better on objective tests of hand-eye coordination and reaction time to visual cues.

One of the dangers of this effect, according to Souza-Formigoni and her colleagues, is that drinkers, especially young ones, may feel free to drink more than they might otherwise have.

It's not clear, Souza-Formigoni said, why study participants felt less drunk when they had the energy drink even though they were still objectively impaired. But in animal research, she and her colleagues have found that some energy drinks ingredients - mostly caffeine and taurine - may counter some of the depressive effects alcohol has on the brain.

The findings in humans, however, suggest that's not enough to avoid becoming drunk.

SOURCE: Alcoholism: Clinical & Experimental Research, April 2006.

- REUTERS