Towards sustainable diets – interventions and perceptions amongst adolescents: a scoping review

Abstract

Adolescence is an important life-stage during which shifts towards more healthy and sustainable diets can be promoted. Adolescents have increasing influence over their food choices informed by their developing personal knowledge and values, impacting long-term dietary behaviours into adulthood(1). We aimed to review the recent literature regarding adolescents’ perceptions of environmentally sustainable diets, and interventions to support adolescents to eat sustainably. We reviewed published literature that focussed on adolescent participants and their perceptions of, or interventions to support, sustainable dietary habits. Five electronic databases were searched to include studies published since 2012 that met the inclusion criteria. The JBI approach and PRISMA-Sc checklist(2) was used for source screening, data extraction and presentation of data. Data was extracted including study characteristics, methodology and results in relation to each research question. The extracted data was reported, synthesised and discussed in the context of the food system framework(3) and broader research. Twenty-eight articles were included in the review. Findings suggest that adolescents’ understanding of what constitutes sustainable eating is low. Most adolescents, when asked, were unsure of what constitutes sustainable eating, or a plant-based diet. The environmental impact of the production methods, transport and packaging of foods was most commonly reported when adolescents considered the environmental impact of their foods. The most commonly perceived barrier to consuming sustainable foods mentioned was cost, particularly by adolescents from lower socioeconomic backgrounds. Other barriers include unappealing taste, appearance or smell of ‘sustainable’ food items (particularly those that were vegetarian). Geographical limitations impacting the ability to grow or purchase local and organic products were also mentioned as barriers to consuming sustainable foods. Adolescents reported a lack of understanding of sustainable diets, and distrust of sustainability-related claims from fast-food outlets regarding the quality or source of ingredients, making it difficult to make informed food choices. Additionally, behaviours conflicting with personal and/or group norms were noted as barriers to adopting sustainable dietary habits. Adolescents that had previously received relevant education, valued nature and health, or were from a rural or indigenous community, were more likely to value environmentally sustainable food choices. Interventions which target adolescents’ cognitive understanding and aspiration to make sustainable food choices appear to improve their attitudes towards sustainable food, whereas interventions to increase the availability of sustainable foods improved the environmental sustainability of adolescents’ dietary intake. Multicomponent, tailored and community-based interventions were most effective however the long-term effect of these interventions remains unclear. More research is needed in diverse countries and settings, with consideration of adolescents’ level of autonomy in food choice and long term-effectiveness of interventions.