A new study has found that best friends and popular classmates influence adolescents in distinctly different ways. Close friends shape internal emotional and academic behaviours, while high-status peers influence public-facing behaviours such as social media use and body image concerns.
Researchers from Florida Atlantic University (FAU) in the United States, working with Mykolas Romeris University, tracked 543 students aged 10–14 over one semester. The middle school students in Lithuania, spanning Years 5–8, completed self-reports on academic performance, emotional well-being, problem behaviours, social media engagement, and weight concerns. They also identified their best friends and nominated popular classmates. Popularity norms were calculated by weighting classmates’ behaviours according to popularity scores.
The findings were published in Development and Psychopathology. According to the researchers, this is the first study to directly compare best friends and popular peers within the same analytical model.
“This is the first study to put best friends and popular peers in the same model and ask, ‘Who matters more, and for what?,’” said Brett Laursen, PhD, a professor of psychology in FAU’s Charles E. Schmidt College of Science.
The results revealed a clear distinction. Best friends primarily influenced internal emotional states and academic behaviours. They were the main drivers of emotional problems, lack of emotional clarity, problem behaviours, and low school achievement.
In contrast, popular peers shaped behaviours that are visible to others. Adolescents were more likely to mirror high-status classmates in social media use and concerns about weight.
“Peer influence is too often treated as a broad, undifferentiated force, but our findings show it is actually highly specialized. Adolescents are discerning; they look to their inner circle for emotional support and to the influencers and class leaders for social cues on how to present themselves to the world,” said Mary Page Leggett-James, PhD, lead author and associate researcher at Gallup, whose doctoral dissertation at FAU formed the basis of the work. “Put differently, in the social economy of a middle schooler, best friends deal in the ‘private currency’ of emotions and adjustment, while popular peers control the ‘public market’ of social media and appearance.”
The researchers suggest that friendships operate through reciprocity and emotional intimacy, while broader peer groups function hierarchically, with visible norms reinforcing status.
“Friendships are powerful because they are private and emotionally intense,” Laursen said. “Teens confide in their best friends. That closeness can provide support, but it can also amplify struggles. Anxiety, disengagement from school, or acting out can spread between friends and have a snowball effect. Appearance and online behavior play out on a public stage. Popular students set the standard. Others follow because that is what earns approval in the wider peer group.”
The findings suggest that interventions should distinguish between friendship dynamics and status-driven peer norms. “Peer influence is powerful, but it is not one-size-fits-all,” said Leggett-James. “Too often we treat peer pressure as if it comes from one place. But the source of influence matters. If we target the wrong peer dynamic, we risk missing the problem entirely. To reduce emotional distress or academic problems, we need to focus on friendship dynamics and help adolescents build positive peer connections, not try to ban or break up friendships. At the same time, issues tied to social media and body image require shifting status norms. When popular students display healthier, more realistic standards, they can redefine what classmates consider normal.”
Co-authors include René Veenstra, PhD, professor of sociology at the University of Groningen in the Netherlands, and Goda Kaniušonytė, PhD, professor at the Institute of Psychology at Mykolas Romeris University.
The research was supported by the European Social Fund under a grant agreement with the Research Council of Lithuania, as well as a state budget-funded project establishing Centres of Excellence at Mykolas Romeris University under the Ministry of Education, Science and Sports of the Republic of Lithuania.