As it turns out, those high school years were a lot more important than you thought, especially when it comes to the friendships you formed in those formative years. A new study from scientists at the University of Virginia found that friendships in high school can result in happiness long after the fact – as much as 10 years later, the study says.

The study found that it was far more important to form deep friendships with a few people than to be popular in school. In fact, researchers found that being popular actually had a negative effect on teens, who went on to experience more social anxiety in adulthood. The findings were based on following 169 teens over 10 years, stretching from 15 to 25 years of age.

People who had close friendships at age 15 not only had less social anxiety, but they also regarded themselves much more highly by age 25, and they were less likely to become depressed.

“Our research found that the quality of friendships during adolescence may directly predict aspects of long-term mental and emotional health,” according to Rachel K. Narr, PhD candidate in clinical psychology at the University of Virginia, who led the study, according to a statement from the Society for Research in Child Development. “High school students with higher-quality best friendships tended to improve in several aspects of mental health over time, while teens who were popular among their peers during high school may be more prone to social anxiety later in life.”