Promoting dietary change. Intervening in school and recognizing health messages in commercials

Sammanfattning: The purpose of this thesis was to examine influences on dietary change among children and adolescents with particular emphasis on individual factors, the school setting and food marketing. The Theory of Planned Behaviour was used to develop a controlled school-based intervention with a focus on fish among 8th grade pupils in the Gothenburg area. Factors influencing fish consumption in school were studied by means of focus group discussions in a school class (n=23) and a questionnaire at two schools (n=162). Fish consumption was measured by observation. In the intervention study, 228 pupils from three schools participated and changes in the school lunch (SL), further augmented by changes in the home economics syllabus (SL+HE) were compared regarding changes in behaviour, attitudes and knowledge. At follow up, fish consumption had increased significantly in the SL+HE group and positive changes in nutritional knowledge were seen in both intervention groups. The frequency and nature of television food advertising to children was compared in eleven countries including Sweden. Television in the three commercial channels most popular with children aged 3-12 years (in Sweden TV3, TV4 and Kanal 5) was recorded between 06:00 and 22:00 for two weekdays and two weekend days (n=192h). In 82 of the Swedish commercials, further analyses of how food was articulated in the health discourse during children’s peak viewing times were carried out by means of discourse analysis. Across countries, the proportion of food advertisements varied (11-29%, in Sweden 18%) as well as advertisements for non-core foods, i.e. foods high in undesirable nutrients and/or energy (53-87%, in Sweden 63%). Overall, the rate of non-core food advertising was higher in children’s peak viewing times and the majority of food advertisements containing persuasive marketing were for non-core foods. Health aspects were used extensively in Swedish commercials; food was articulated as treatment or protection, as feeling good or as caring. Some foods with unhealthy associations (e.g. hamburger meals, crisps and high-fat dairy) were endorsed as ‘healthier’ by means of offensive rhetoric.