Associations between loneliness and psychological health symptoms as well as dietary habits in adolescents: Sex differences.

Background: Adolescence is a stage of high prevalence of loneliness. However, research on the associations between loneliness and psychological health as well as dietary habits in adolescents remains limited. Therefore, this study aimed to explore these associations and potential sex differences.

Methods: Between November 2023 and January 2024, this study included 3654 adolescents. A range of scales were used to assess participants' loneliness, depression, anxiety, sleep quality, non-suicidal self-injury (NSSI) and dietary habits. Finally, logistic regression analysis was conducted to identify independent correlates of loneliness.

Results: The prevalence of loneliness in adolescents was 45.9 %. In total sample, sex, age, heavy academic pressure, the Children's Depression Inventory (CDI) total score, the Multidimensional Anxiety Scale for Children (MASC) total score, the Pittsburgh Sleep Quality Index (PSQI) total score, NSSI, and fresh vegetable intake weekly were independent correlates of loneliness. In males, age, heavy academic pressure, CDI total score, MASC total score, and PSQI total score were independent correlates of loneliness. In females, CDI total score, MASC total score, PSQI total score, NSSI, and fresh vegetable intake weekly were independent correlates of loneliness.

Limitations: The cross-sectional design resulted in our inability to make causal inferences about the findings.

Conclusion: Chinese adolescents, particularly females, were at a relatively high risk of loneliness. Loneliness was strongly associated with depression, anxiety, poor sleep quality, NSSI and dietary habits, such as low frequency of vegetables intake. There were also some sex differences in these associations. Based on these findings, teachers and parents should closely monitor adolescents' loneliness and implement targeted psychological interventions.