Public health campaigns intended to reduce unhealthy behaviors like binge drinking and eating junk food often focus on the risks of those behaviorsb but a new study in the Journal of Consumer Research suggests a relatively simple but surprisingly effective strategy to improve consumer health based on common sense: like the risky behavior with an 'out' group.

Authors Jonah Berger from the University of Pennsylvania and Lindsay Rand from Stanford University found that linking a risky behavior with a group that the targeted audience doesn't want to be associated with caused participants to reduce unhealthy behaviors.

The studies began by identifying groups of people who study participants liked, but with whom the participants would not want to be confused — "outgroups." In the first study, the participants were undergraduates and the "outgroup" was graduate students. When participants were led to believe that graduate students consumed more junk food, they chose 28% fewer junk-food items than participants who thought their group ate more junk food.

So make risky behavior uncool. This seems like a more agreeable solution than culturally fundamentalist solutions like banning smoking in movies or banning ingredients in fast food.

"We suggest that public health campaigns will be more successful if they attend to how behaviors act as markers or signals of identity," the authors write.

In another study, researchers placed fliers in freshman dormitories on a college campus. In one dorm, the fliers emphasized the health risks of binge drinking. In another dorm, the fliers linked binge drinking to graduate students. Participants in the dorm with the second flier consumed at least 50 percent less alcohol than those who saw the health risk fliers.

In a third study, students on their way to a campus eatery were surveyed about perceptions of the media. A control group read an article about politics and pop culture, and a second group read an article associating junk-food eating with online gamers (an "outgroup"). When research assistants observed the two groups ordering food, they found that the group who had read the article about online gamers made healthier choices.

These studies highlight the importance of identity in health behavior and suggest promising directions for future health promotion appeals, the authors believe. "Decisions are not only based on risks and benefits, but also the identity that a given choice communicates to others. Consequently, shifting perceptions of the identity associated with a risky behavior can help make better health a reality."