The individual and interrelated roles of social environments and physical food environments on the food purchasing and dietary behaviours of adolescents.

Abstract

Poor dietary behaviours by adolescents are a public health concern because of the negative impacts on their immediate and future health, as well as the health of their future offspring. During adolescence, many young people start making more independent food choices. Evidence suggests that the physical food environments outside of the home and the people adolescents spend time with, their social environment, can affect these decisions. Knowledge of how these environments interact to affect adolescents’ food choice is limited. This thesis addressed this gap by investigating the individual and interacting relationships of the social environment and physical food environment on adolescents’ food purchasing and dietary behaviours. A convergent parallel mixed-methods research design was applied. A total of 108 adolescents participated in the quantitative component, which included completing questionnaires about their dietary behaviours and social networks, as well as using an ecological momentary assessment mobile phone app for one week. This app recorded novel data on adolescents’ GPS tracked journeys, their use of food outlets and details about their independent food purchases. In the qualitative component, 13 focus groups with 45 adolescents were conducted to understand the experiences of young people when purchasing food from different environments. Adolescents who made less healthy purchases had poorer quality diets and this relationship was strongest among adolescents from lower socio-economic backgrounds. Both social environments and physical food environments were shown to be associated with these behaviours. Friends were most strongly associated with making less healthy purchases and parents were shown to have the biggest influence on overall diet quality. Adolescents’ exposure to food outlets during their daily activities was dominated by unhealthy food outlets with 95% of adolescents being exposed to more unhealthy outlets than healthy outlets. Adolescents with greater exposure to healthier food outlets tended to have better quality diets, with the strongest relationship observed among adolescents from lower socio-economic backgrounds. Fast-food outlets, cafes, small supermarkets, and convenience stores were the food outlets used most frequently by young people; when marketing strategies inside these outlets, such as lower price, were present on the foods adolescents purchased, these purchases were more likely to be less healthy. Qualitative findings demonstrated complexity in the interplay between social environments and physical food environments and their relationship with adolescents’ food choices. Adolescents valued the way that food purchases could enhance their social interactions, particularly with their friends. These social interactions often occurred in food environments which heavily promoted unhealthy foods because they offered a welcoming space with affordable, familiar, and popular food. The findings from this thesis provide evidence that adolescents’ social environments and physical food environments adolescents are highly interrelated in their influence on their independent food choices. Future research and policy initiatives to improve adolescent diet should find ways to offer physical food environments that meet adolescents' values and social needs, yet also provide more healthy foods at affordable prices.

More information

Identifiers

ORCID for Sarah Christine Shaw: orcid.org/0000-0002-2206-6858

ORCID for Christina Vogel: orcid.org/0000-0002-3897-3786

ORCID for Cyrus Cooper: orcid.org/0000-0003-3510-0709

ORCID for Dianna Smith: orcid.org/0000-0002-0650-6606

ORCID for Mary Barker: orcid.org/0000-0003-2976-0217

ORCID for Sarah Crozier: orcid.org/0000-0002-9524-1127

Catalogue record

Export record