Influences in home, school and community environments on the dietary behaviours of overweight/obese adolescents

The research presented in this thesis explored relationships between healthful eating and food environments among overweight/obese adolescents. The three aims were to: 1) examine associations between parent and adolescent diets, 2) determine associations between a range of factors in the home food environment and adolescent diets, and 3) explore perceived factors that impede or facilitate healthful eating within home, school and community environments among adolescents. A secondary data analysis of baseline data collected from 176 parent-adolescent (11-16 years old) pairs who presented for an e-health intervention was conducted. Parent and adolescent intake of specific foods (vegetables and fruit (VF), total fat, sugar-sweetened beverages (SSB), desserts/treats, and snacks) was assessed from up to three 24-hour dietary recalls, while demographic and household factors were collected from questionnaires. Analyses examined associations between adolescent diets and the following parent and household factors: parent intake, parent modeling, parenting style, family meal practices, and home food and beverage availability. Upon completion of the intervention, a subset of 22 adolescents took part in a photovoice study to explore perceived barriers and facilitators to healthful eating within the home, school and community settings. Parent intake was positively associated with adolescent intake for all dietary components except for desserts/treats. Both parent modeling of healthful food choices and healthier family meal practices were associated with fewer high fat food items and soft drinks in the home, but neither were directly related to adolescent intake. The availability of less healthful foods at home was related to intake of fat, SSB, desserts/treats and snacks. These findings were further expanded by adolescents’ photographs depicting a struggle with an obesity-promoting environment. At home, themes that emerged included family meals, availability, parenting practices, modeling, celebrations, accessibility, and screen use. In the school and community, themes that emerged included availability, peers, convenience, price, school practices, marketing, and online influences. Targeting the home food environment through family-based obesity interventions and minimizing opportunities for less healthful eating in schools and communities may support dietary behaviour change among overweight/obese adolescents. Socio-ecological and systems-based approaches may help to conceptualize links between the multiple influences on dietary behaviour.Medicine, Faculty ofPopulation and Public Health (SPPH), School ofGraduat