Home environmental influences on adolescents' energy balance related behaviours. The HEIA cohort study

• Main Author: Totland, Torunn Holm
• Format: Dissertation
• Language: English

The global obesity epidemic represents an enormous potential threat to public health, because overweight and obesity are major risk factors of non-communicable diseases. The prevalence of overweight has furthermore increased among children and adolescents worldwide, and creates a growing health challenge for the next generation as children who are overweight are more likely to become overweight and obese as adults. Dietary, physical activity and sedentary behaviours are energy balance related behaviours (EBRB) that positively or negatively are related to weight status. It is agreed upon that the obesity epidemic is driven by large environmental changes over the past few decades, negatively influencing the EBRB. Social inequalities are furthermore consistently observed in children’s and adolescents’ weight status and health behaviours. Thus, there is a need for research to identify environmental factors influencing children’s and adolescents EBRB across age and within diverse social groups, in order to establish good opportunities of a healthy future. The main aims of this thesis were first to investigate the changes and tracking in children’s dietary behaviours during the transition into adolescence, and possible differences by parental education. Second to examine how the home environment influences young adolescents’ dietary and sedentary behaviours between the ages of 11 and 13 years, including social differences as measured by parental education. Longitudinal data from the Norwegian HEalth In Adolescents (HEIA) cohort study (2007–09) is included. Data was collected through questionnaires among a baseline sample of 975 adolescents at the age of 11 years (T0), and followed up at age 12 (T1) and 13 (T2) years. Furthermore, questionnaires were collected from both mothers (n=738) and fathers (n=630) at T0, and followed up at T2. Dietary intakes of fruits, vegetables, energy dense snacks, sugar sweetened soft drinks and sugar sweetened squash were examined prospectively, as well as screen time behaviours of television and video viewing (TV/DVD), and computer and electronic game use (PC/game). Parental education, parental modelling, parental regulation, availability and accessibility were explored as possible determinants in the home environment. Analyses of tracking was used to investigate changes and stability in dietary behaviours over time, and mediation analyses explored possible influences of the home environment on adolescents’ prospective soft drink i