This study aimed to investigate relationships between measures of diet quality and adolescent mental health, both cross-sectionally and prospectively. It also aimed to examine the temporal relationships between diet quality and mental health and the associations between change in diet quality and change in psychological symptoms.
An unhealthy diet can be the cause of mental health problems in adolescents, a new study has found. Three quarters of lifetime psychiatric disorders will emerge in adolescence or early adulthood. The National Comorbidity Survey Replication recently reported that more than 22% of adolescents aged 13 to 18 yrs had already experienced a clinically significant mental health problem, with ages of onset ranging from 6 yrs for anxiety disorders, to 13 years for mood disorders. In the last 18 months there have been a number of published studies identifying an inverse associations between diet quality and the common mental disorders, depression and anxiety, in adults and two prospective studies suggesting that diet quality influences the risk for depressive illness in adults over time. While two recent studies have also demonstrated cross-sectional associations between diet quality and emotional and behavioural problems and depression in adolescents, there are no existing studies that examine this association in adolescents prospectively, limiting inferences regarding possible causal relationships.