The experiences of adolescence lay the foundation for adulthood and influence physical and emotional health, as well as social and vocational choices. During adolescence, teens begin to turn away from their families and to their peers for support and feedback. This can mean they often feel pressure to be accepted by the larger peer group. A recent study looked at the ways that the friendships formed during adolescence influence mental health, both during the teen years and into early adulthood.

The researchers distinguished between close friends (dyadic relationships) and peer group acceptance. They suspected that each type of friendship would have distinct impacts because the relationships differ in substantial ways. What they found suggests that having close friends in adolescence can be a tremendous resource, even into adulthood.

Being part of the “in-crowd” may not always be as desirable as it looks. Having one or more close relationships is far better for adolescents' development.

Close, one-on-one friendships support a teen's sense of being unique; acceptance by a larger peer group may not provide those feelings of specialness. Close friendships are characterized by sharing confidences and other exchanges of intimate thoughts and feelings by participants; by loyalty and support for a friend's self-esteem; and, of course, by feelings of connectedness between friends.

By contrast, acceptance in a peer group is not dependent upon intimacy and reciprocity, but rather the ability to navigate social hierarchies, and sometimes, the willingness to participate in risk-taking or socially aggressive behaviors.

The researchers followed almost 170 adolescents over a ten-year period, from ages 15 to 25. The teens came from racially and ethnically diverse backgrounds. Each year the students in the study answered standardized questionnaires measuring self worth, the strength of their close friendships, peer affiliation preferences, feelings of social acceptance and social anxiety.

There was a strong positive relationship between having close friendships at age 15 and experiencing an increase in feelings of self-worth at 25. Close friendships also predicted a positive change in feelings of social acceptance. These were not seen in students whose primary relationships were with a peer group, but who did not identify a close relationship.

Students who had close friendships at age 15 had fewer depressive symptoms over the period from age 15 to 25. They also tended to have more close friendships and increases in self-worth scores over that ten-year period. Peer affiliation — just being part of a social group — did not predict positive changes in either depressive symptoms or self-worth scores.

Have one or more close friendships at age 15 also was related to having less social anxiety at age 25. In contrast, the researchers found that peer affiliation at age 15 predicted an increase in social anxiety at age 25.

These two types of social relationships, close friendships and peer affiliation, have different impacts on mental health and social functioning both during adolescence and extending into early adulthood. The researchers suggest that close friendships can have both a protective function and positive influence as to how teens seen themselves and how they learn to maneuver the challenging landscape of adolescent relationships.

Close friendships can be reassuring and affirming. Being accepted by a close friend helps teens establish their identities, adjust to the demands of school and society, and develop self-esteem. When an adolescent has successful close friendships, he or she may learn to expect future positive peer and romantic relationships. This expectation can lead to increased success in future relationships.

The findings suggest that being part of the “in-crowd” may not always be as desirable as it looks. Having one or more close relationships is far better for adolescents' development. Teens should be encouraged to value trusting and caring relationships, apart from peer group relationships.

The study is published in Child Development.