Peer pressure may be a good thing. Teenagers who have close friends are more likely to have better health as young adults, HealthDay News reports of research from the University of Virginia in Charlottesville. "These results indicate that remaining close to--as opposed to separating oneself from--the peer pack in adolescence has long-term implications for adult physical health," wrote study co-author Joseph Allen in the journal Psychological Science.

Find out the five biggest risks that teenagers are taking--when their parents aren't looking.

The study: The UVA team followed 171 girls and boys who were in the seventh and eighth grades at the beginning of the study. At regular intervals between the ages of 13 and 17, the researchers evaluated the quality of the teens' friendships and their efforts to fit in with peers. When the same young people were 25, 26 and 27, the researchers assessed their physical health.

The results: Those who enjoyed high-quality friendships and had a high desire to fit in with their peers during adolescence had far better health at age 27 than those who separated themselves from their peers during the teenage years. This held even after the researchers accounted for other factors, including income, weight and drug use.

Why? Strong friendships and a feeling of being part of a group as a teenager may influence adult health by lowering anxiety and stress levels.

"Peer relationships provide some of the most emotionally intense experiences in adolescents' lives, and conformity to peer norms often occurs even when it brings significant costs to the individual," Allen wrote in Psychological Science, noting that placing the desires of one's peers ahead of one's own goals--much as adolescents do when they conform to peer norms--is linked to reduced life stress.

One caveat: The study showed only an association--and not a cause-and-effect relationship--between having close friends in adolescence and better health as an adult.

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