Characteristics of supermarket-based interventions to improve the dietary quality and environmental sustainability of diets in people living with obesity, overweight and/or food insecurity in high-income countries: a scoping review.

Food insecurity (FI), defined as unreliable access to healthy, nutritious food, is a major health concern in higher-income countries, primarily due to its association with an increased risk of obesity. Supermarket-based interventions may influence population-level food purchasing behaviour, an antecedent to consumption. It is unclear whether there are specific characteristics that these interventions should employ to resonate with vulnerable groups. This scoping review aimed to explore the characteristics of supermarket-based interventions that sought to support healthier and/or more environmentally sustainable food purchasing for people living with obesity, overweight (PLWO/Ow), and/or FI. A systematic literature search, conducted in Medline, Embase, CINAHL, Scopus, and Web of Science databases, identified 35 eligible studies, representing 43 interventions. Title and abstract screening and data extraction were conducted independently by two reviewers. Most interventions focused on supporting the purchase of healthy food items. No study applied a validated measure of FI. Area-level demographic data were used to identify FI related characteristics (i.e., area of low income, low socio-economic status) and in some cases, those living with obesity. Interventions utilised the behaviour change levers of price (n=8), promotion (n=2), placement (n=7), nudges (n=4) and education (n=2), or a combination of these (n=20). High heterogeneity in the way behavioural change levers were operationalised and combined, alongside the use of proxy measures to identify FI and PLWO/Ow, makes it difficult to determine the most supportive intervention characteristics. This presents challenges understanding how to best facilitate changes in purchasing patterns in favour of heathy, sustainable food items in this population.