America’s teens are depressed.

The number of US teens ages 12 to 17 who said they experienced at least one major depressive episode in 2017 increased by 59% since 2007. That’s a total of 3.2 million teens, or 13% of the entire cohort, according to a Pew Research Center analysis of data from the 2017 National Survey on Drug Use and Health.

The most prominent symptom of major depression is “a severe and persistent low mood, profound sadness, or a sense of despair,” according to Harvard Medical School.

Teen girls have it the worst — they’re three times as likely as teen boys to deal with depression. Per Pew, 20% of teen girls cited having a major depressive episode in 2017, compared to 7% of teen boys. The percentage of teen girls (66%) who recently experienced depression also increased at a faster rate than it did for teen boys (44%) from 2007 to 2017. However, teen girls are more likely to receive treatment, Pew found.

Depression might be related to the daily pressures teens are facing. A 2018 Pew study found that 61% of teens of any gender felt pressure to get good grades, 29% felt pressure to look good, and 28% felt pressure to fit in socially.

Teen years are an important indicator of mental health as a young adult. Teens who feel more connected, defined as engaged, supported, and cared for, at home and school are less likely to experience mental health problems and risks, reported HealthDay News, citing a recent CDC study published by the journal Pediatrics.

Overall, the mental health outlook isn’t looking good for younger generations — depression is also on the rise among millennials.

Originally published on Business Insider.

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