Identifying effective evidence‐based strategies to promote sustainable and healthy diets

Global food systems and our dietary behaviours have significant impact on health outcomes and environment. More specifically, they increase greenhouse gas emissions, deforestation of agricultural land, and the use of freshwater resources. Therefore, there is a need for whole food systems transformation to address these negative impacts. Although, there has been an increase in interventions developed to promote sustainable and healthy diets, there is no synthesised evidence on the effectiveness of such interventions and lack of research on people's understanding of sustainable and healthy diets. Therefore, this thesis aimed to address these gaps in the literature. This thesis consists of two research studies: 1) a systematic literature review which synthesised the evidence on the effectiveness of interventions aiming to promote sustainable protein intake; and 2) a qualitative study, which explored young Australian's understanding of sustainable diets and their efforts in achieving it. The first study was a systematic literature, which was conducted in accordance to PRISMA guidelines. The second study was a qualitative study, which used semi‐structured interviews to collect data. The systematic review included 50 studies which were categorised into individual and micro‐environmental level studies. The findings demonstrated reduction of unsustainable protein intake post intervention, mainly decrease in red and/or processed meat intake. However, there is a need for: i) longitudinal studies to see if the behaviour change sustains over time; ii) development of interventions targeting population without a risk factor or disease to investigate if these strategies are effective; and iii) further research is needed to test some micro‐environmental strategies in changing unsustainable protein intake. For the qualitative study, 22 young Australians (aged 18 to 25 year old) were recruited. Two thirds of participants were aware of some aspects of sustainable and healthy diets. Although, majority of participants showed an intention in practicing sustainable diets, less than half of them were practicing it due to barriers such as high costs, unavailability of sustainable and healthy food and low food literacy levels including cooking skills. This thesis contributes to the body of knowledge on our understanding of implemented strategies to promote sustainable protein intake and young Australians' understanding of sustainable diets. It identified numerous barriers and enablers in promoting sustainable and healthy diets which could be used in development of effective health promotion interventions to improve health and environmental outcomes -- abstract.