Insomnia severity and obesity mediated by health behaviors in adolescents.

Objective: Sleep difficulties in youth have been associated with numerous negative outcomes, such as higher risk of obesity. Though the relationship between sleep and obesity is not well clarified, past research has shown that modifiable health behaviors, such as diet, physical activity, and screen time, may explain this relationship. The purpose of this study was to simultaneously examine these health behaviors as mediators of the relationship between insomnia severity and obesity among a sample of adolescents aged 12-18 years.

Method: English-speaking parents/legal guardians of adolescents were invited to participate in an online survey focused on pediatric sleep patterns, health behaviors, and weight. Parents/guardians (N = 599) reported on their adolescent's diet (i.e., consumption of fruits/vegetables, fast food, and breakfast), physical activity, screen time, and BMI. A multiple mediation analysis was run to test these health behaviors as mediators of the relationship between insomnia severity and BMI, after controlling for sex, age, race, and poverty.

Results: While insomnia was related to most health behaviors, screen time was the only significant mediator of the relationship between insomnia and BMI, after controlling for the effects of the other mediators and all covariates, ab = .04, 95% CrI [.01, .09].

Conclusions: Screen time has implications for both adolescents' sleep health and weight. Pediatric clinicians should systematically assess for, and provide, recommendations on ways to improve sleep and screen time use, in addition to providing traditional dietary and physical activity recommendations.