Girls’ Mental Health Problems Tripled — More Serious Problems Were Increasingly Seen Together

Mental health problems among teenage girls rose sharply in a Swedish study comparing school cohorts 17 years apart. More serious problems also appeared increasingly alongside broader mental health difficulties.

The study compared students of roughly the same age in the same Swedish municipality in 2007–2008 and 2024–2025. In each period, the students were assessed twice, one year apart, using the same measures.

The share of girls who crossed the screening threshold for clinically significant mental health problems rose from about 10 percent to about 30 percent. The figures were 10.3 and 9.2 percent in 2007 and 2008, compared with 33.4 and 29.5 percent in 2024 and 2025.

More Serious Problems Were Increasingly Seen Together

The researchers also looked at repeated non-suicidal self-injury, which is intentional self-harm without suicidal intent, and disordered eating.

According to the researchers’ statistical model, repeated self-injury combined with clinically significant other mental health problems increased among girls from 6.6 percent to 21.0 percent. High-risk disordered eating combined with other significant mental health problems rose from 2.7 percent to 8.7 percent.

Importantly, repeated self-injury and high-risk disordered eating did not become more common among girls whose other mental health symptoms remained below the study’s screening threshold.

The rise was not limited to more girls crossing a general mental health screening threshold. Harmful behaviors were also appearing more often alongside a broader pattern of significant symptoms.

Could Greater Awareness Explain the Rise?

The researchers also considered the so-called prevalence inflation hypothesis. One possibility raised in debates about worsening youth mental health is that greater awareness leads young people to recognize and label ordinary difficult experiences as mental health problems more readily than in the past.

Self-injury and disordered eating, however, are more concrete behaviors than a general report of psychological distress. The researchers argue that their increase alongside broader mental health problems supports the interpretation that at least part of the rise reflects a genuine deterioration in mental health.

The pattern was different among boys. Their average mental health symptoms also increased. The share of boys showing elevated mental health symptoms rose from 6.3 and 8.8 percent in 2007 and 2008 to 16.7 and 14.9 percent in 2024 and 2025. Repeated self-injury did not become more common. The proportion of boys reporting non-suicidal self-injury at least once actually fell significantly between the two study periods.

The Study Cannot Explain Why Mental Health Worsened

The study does not identify what caused the increase. It compared two different generations of adolescents in one Swedish municipality 17 years apart, so the design cannot isolate the effects of social media, school pressure or other social changes.

The results were also based on self-reported questionnaires and screening cutoffs rather than clinical diagnoses. The long-term comparison of disordered eating was conducted only among girls.

There were 992 respondents in 2007 and 987 in 2008. In the newer cohort, 810 responded in 2024 and 836 in 2025. Response rates were about 90 percent in the earlier period and about 80 percent in the newer one.

The study was conducted by researchers at Lund University and Kristianstad University and was published in European Child & Adolescent Psychiatry on June 22, 2026. Lund University published an English-language research news release about the findings on September 23.

Updated October 2, 2026: This article was updated to include additional figures on mental health symptoms among boys.