Lifestyle Behavior and Mental Health in Early Adolescence

Mental illnesses affect >15% of Canadian adolescents. New preventive strategies are critically needed. We examined the associations of meeting established recommendations for diet, physical activity, sleep, and sedentary behavior in childhood with mental illness in adolescence.

Population-based prospective study (n = 3436) linking 2011 health behavior survey data of 10- to 11-year-olds with administrative health data from 2011 to 2014. Lifestyle behaviors were measured with the Harvard Food Frequency Questionnaire and self- and parental-proxy reports, expressed as meeting recommendations for vegetables and fruit, grain products, milk and alternatives, meat and alternatives, added sugar, saturated fat, sleep, screen time, and physical activity. Mental illness was defined by physician-diagnosed internalizing, externalizing, and other psychiatric conditions. Negative binomial regression was used to determine the independent and cumulative associations of meeting lifestyle recommendations with physician visits for mental illnesses.

Of all participants, 12%, 67%, and 21% met 1 to 3, 4 to 6, and 7 to 9 recommendations, respectively, and 15% had a mental illness diagnosis during follow-up. Compared with meeting 1 to 3 recommendations, meeting 7 to 9 recommendations was associated with 56% (95% confidence interval: 38%-69%) fewer physician visits for mental illness during follow-up. Every additional recommendation met was associated with 15% fewer physician visits for mental illnesses (95% confidence interval: 9%-21%).

Mental illness in adolescence is associated with compliance to lifestyle recommendations in childhood, with stronger associations seen when more recommendations are met. Emphasizing lifestyle recommendations in pediatric practice may reduce the future burden of mental illness.