Like so many other socially “contagious” traits that have been studied before it — among them, happiness, loneliness, generosity, obesity, disordered eating and quitting smoking — teenagers’ drinking behavior may be influenced by their social networks, a new study finds.
But in a twist, the study found that some second-degree relationships were more influential than close friends and romantic partners. Specifically, the authors report, teenagers with a new dating partner were more likely to adopt the drinking habits of their boyfriend’s or girlfriend’s friends, rather than those of the partners themselves.
The partner’s friends were even more likely to influence changes in teen drinking than the teenager’s own friends. So, for instance, the chances of binge drinking were more than twice as high in teens whose partner’s friends drank heavily than in those whose partners or friends binge drank, the study found.
It makes sense when you consider the social lives of adolescents. Most teens are friends with other people who are already like them in terms lifestyle and values (and gender, the study found). But when teens start dating, they tend to hook up with partners who come from a different social circle.
“Think of your son or daughter’s new significant other as a bridge to a whole other group that he or she is now going to be exposed to,” lead researcher Derek Kreager, an associate professor of crime, law, and justice at Pennsylvania State University, explained to Health.com.
The two who are dating may be impelled to change their behaviors to better match one another — drinking more or less to keep pace with the other person — but the partners’ friends have no such incentive. And teens, being so keenly motivated to seek social acceptance, are likely to adopt the behaviors of new social groups, especially if they think that’s what their romantic partners prefer.
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To determine how drinking and dating mixed, Kreager and his colleagues analyzed survey results from 898 students, who participated in a larger national study on adolescent health. The researchers interviewed the teens when they were in 7th through 12th grades, asking about their drinking habits and who their close friends were. Two years later, they followed up with the students, this time inquiring about any new romantic relationships. Researchers then compared the survey responses of coupled teens to figure out how their partners’ social networks may have affecting changes in drinking habits.
Although the frequency and volume of teens’ alcohol consumption was certainly affected by the habits of their dating partners and close friends, these influences were outweighed by the behaviors of the new boyfriend or girlfriend’s social networks.
Health.com reported:
The findings may not be news to parents, Kreager says. But they do emphasize the need to learn more about the group of people their children’s romantic partners — and therefore their children — may be spending time with.
Parents should talk with their children about peer pressure and alcohol abuse even before they begin dating, says [Mount Sinai Medical Center’s adolescent health research director Dr. Angela] Diaz, so that as teenagers they can recognize potential hazards in new social situations. They should also make an effort to get to know a new romantic partner in their teen’s life, as well as that partner’s friends.
The good news is that not all peer influences are bad. The study found that drinking less is also contagious, which may be especially good news for boys. “Consistent with prior literature, our findings indicate that girls are significantly less likely than their male partners to binge drink,” Kreager said. “Moreover, our research suggests that, if anything, males are more susceptible to a significant other’s influence than are girls.”
MORE: How Social Networks Impact Drinking Habits — In Adults
Meredith Melnick is a reporter at TIME. Find her on Twitter at @MeredithCM. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.