Clearing up misconceptions about how much college students drink can reduce alcohol consumption on campuses, according to a study from the University of North Carolina at Chapel Hill. Researchers found that the image of a typical college student as a drunken frat boy is largely a myth. Moreover, when students find out that their classmates are relatively modest in their drinking habits, they cut back on their own drinking as well.

Researchers led by Robert Foss of the UNC Highway Safety Research Center used voluntary breathalyzer tests to measure the blood alcohol concentration (BAC) of students returning at night to their living quarters. In an initial sample of over 2,000 students, the research team found that on 'party nights,' two out of three students hadn't had a drop to drink. On Mondays through Wednesdays, fully 85 percent had no alcohol in their systems—findings at odds with the stereotype of beer-swilling 'party schools.'

Calling their campaign "2 out of 3, 0.0 BAC", the research team publicized their findings through on-campus talks and posters distributed to every dorm room—randomly selecting students who'd displayed the posters for $50 bonuses. When the researchers polled students much later, 91 percent of respondents had heard of the slogan.

More important, the message got across: student drinking had declined. The fraction of students returning home with alcohol in their bodies had decreased by 15 percent. BACs greater than .05—the point by which many cognitive functions begin to be affected—were down by 23 percent. In addition, the average number of drinks consumed by those who were drinking decreased from 5.1 to 4.3.

According to Foss, once students have a valid concept of how much their peers are actually drinking, they tend to follow suit. "A great deal of what humans do is strongly influenced by social norms," he says. "Rather than telling students what to do, these programs say 'This is what we do around here,' and leave it at that. Students feel like it's respectful."

Foss cautions, however, that a social norms approach is not a cure-all for campus drinking problems. "The social norm part is only an attempt to attack one piece of an environment that facilitates and encourages excessive drinking. There are many more things that need to be done."