PhD defence A. (Annemieke) Wargers

Below is a brief summary of the dissertation:

Obesity in childhood and adolescence is a growing public health concern, driven by unhealthy lifestyle behaviours such as a poor diet and low physical activity. Socioeconomic status (SES) influences these behaviours, with adolescents from low SES backgrounds facing greater challenges. Schools are a promising place to perform health promoting interventions, as they reach children across all SES levels. Instead of researchers developing interventions, participatory research ensures engaging young people in developing and/or implementing health-promotion strategies.
The aims of this thesis were 1) to investigate determinants of healthy lifestyles behaviours of adolescents in Europe, especially from low SES areas and 2) to develop and evaluate participatory interventions promoting healthy lifestyles among children and adolescents from low SES areas.
Results showed that the majority of European adolescents do not consume fruit and vegetables on a daily basis. A seemingly widening gap in dietary behaviour between adolescents from different SES backgrounds should be addressed in new policies, as well as differences between ages and sex. 
Regarding perceived barriers and facilitators for a healthy diet and physical activity, both adolescents and stakeholders from schools, community and the government mainly mentioned that schools can be improved to turn into health promoting environments.
Furthermore, we found that participatory methods led to clear and feasible ideas of needed interventions among European adolescents. However, whether those participatory interventions are effective to improve healthy lifestyles remains unclear. Future research should investigate the underlying reasons for the lack of effects and the most suitable participatory methods to be used.