BackgroundDue to their central position in the modern food system, food stores present a unique opportunity to promote healthy dietary behaviour. However, there is a lack of insight into the factors that impede or enhance the implementation of nutritional interventions in food stores. We applied a systems innovation and implementation science framework to the identification of such barriers and facilitators.MethodsWe conducted a systematic literature review. A search string was developed to identify qualitative and quantitative articles on environmental nutritional interventions in the food store. Four databases were systematically searched for studies published between 2000 and 2018. Eligible publications described study designs or original studies, focused on stimulating healthier dietary behaviour through environmental changes in retail settings and contained information on the perceptions or experiences of retailers or interventionists regarding the implementation process of the intervention. Context-descriptive data was extracted and a quality assessment was performed.ResultsWe included 41 articles, of which the majority was conducted in the USA and involved single stores or a mix of single and multi-store organisations. We categorized barriers and facilitators into 18 themes, under five domains. In the ‘outer setting’ domain, most factors related to consumers’ preferences and demands, and the challenge of establishing a supply of healthy products. In the ‘inner setting’ domain, these related to conflicting values regarding health promotion and commercial viability, store lay-out, (insufficient) knowledge and work capacity, and routines regarding waste avoidance and product stocking. In the ‘actors’ domain, no major themes were found. For the ‘intervention ‘domain’, most related to intervention-context fit, money and resource provision, material quality, and the trade-offs between commercial costs and risks versus commercial and health benefits. For the ‘process’ domain, most factors related to continuous engagement and strong relationships.ConclusionsThis review provides a comprehensive overview of barriers and facilitators to be taken into account when implementing nutritional interventions in food stores. Furthermore, we propose a novel perspective on implementation as the alignment of intervention and retail interests, and a corresponding approach to intervention design which may help avoid barriers, and leverage facilitators.Trial registrationPROSPERO; CRD42018095317.

We explored experts’ perceived challenges and success factors in the recruitment of adults with a low socioeconomic position (SEP) for participation in community-based lifestyle modification programs. We conducted semi-structured interviews with 11 experienced project coordinators, based on a topic list that included experiences with recruitment, perceived barriers and success factors, and general views on recruitment strategies. Results revealed challenges related to the context of the program (e.g., limited program resources), psychosocial barriers of the participants (e.g., mistrust or skepticism), practical barriers (e.g., low literacy or having other priorities), and reasons to decline participation (e.g., lack of interest or motivation). Success factors were related to securing beneficial contextual and program-related factors (e.g., multi-layered recruitment strategy), establishing contact with the target group (e.g., via existing networks, community key-members), methods to increase engagement (e.g., personal approach and involvement of the target group in the program process) and making participation easier (e.g., providing transport), and providing various types of incentives. Concluding, the group of participants with low SEP covers a wide spectrum of individuals. Therefore, multiple recruitment strategies at multiple layers should be employed, and tailored. The lessons learned of those with hands-on experiences will help to enhance recruitment in future programs.

BackgroundInitiating and maintaining a healthy lifestyle -including healthy eating and sufficient physical activity- is key for cardiometabolic health. A health-promoting environment can facilitate a healthy lifestyle, and may be especially helpful to reach individuals with a lower socio-economic status (SES). In the Supreme Nudge project, we will study the effects of pricing and nudging strategies in the supermarket – one of the most important point-of-choice settings for food choices – and of a context-specific mobile physical activity promotion app. This paper describes the stepwise and theory-based design of Supreme Nudge, which aims to develop, implement and evaluate environmental changes for a sustained impact on lifestyle behaviours and cardiometabolic health in low SES adults.MethodsSupreme Nudge uses a multi-disciplinary and mixed methods approach, integrating participatory action research, qualitative interviews, experimental pilot studies, and a randomized controlled trial in a real-life (supermarket) setting. First, we will identify the needs, characteristics and preferences of the target group as well as of the participating supermarket chain. Second, we will conduct a series of pilot studies to test novel, promising and feasible intervention components. Third, a final selection of intervention components will be implemented in a full-scale randomised controlled supermarket trial. Approximately 1000 low SES adults will be recruited across 8–12 supermarkets and randomised at supermarket level to receive 1) no intervention (control); 2) environmental nudges such as food product placement or promotion; 3) nudges and a tailored physical activity app that provides time- and context specific feedback; 4) pricing interventions, nudges, and the physical activity app. The effects on dietary behaviours and physical activity will be evaluated at 3, 6 and 12 months, and on cardiometabolic health at 6 and 12 months. Finally, we will evaluate the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) of the intervention, and we will use insights from System Innovation and Transition Management theories to define the best strategies for implementation and upscaling beyond the study period.DiscussionThe Supreme Nudge project is likely to generate thorough evidence relevant for policy and practice on the effects of a mixed method and multi-disciplinary intervention targeting dietary behaviours and physical activity.Trial registrationThe real-life trial has been registered on 30 May 2018, NTR7302.

Background: Unhealthy lifestyle behaviours such as unhealthy dietary intake and insufficient physical activity (PA) tend to cluster in adults with a low socioeconomic position (SEP), putting them at high cardiometabolic disease risk. Educational approaches aiming to improve lifestyle behaviours show limited effect in this population. Using environmental and context-specific interventions may create opportunities for sustainable behaviour change. In this study protocol, we describe the design of a real-life supermarket trial combining nudging, pricing and a mobile PA app with the aim to improve lifestyle behaviours and lower cardiometabolic disease risk in adults with a low SEP.

Nudging has received ample attention in scientific literature as an environmental strategy to promote healthy diets, and may be effective for reaching populations with low socioeconomic position (SEP). Therefore, the objective of this study was to investigate how the determinants of food choice shape the perceptions regarding supermarket-based nudging strategies among adults with low SEP. We conducted semi-structured interviews among fifteen adults with low SEP using a pre-defined topic list and visual examples of nudges. Interviews were recorded and transcribed verbatim and content analysis was used to analyse the data. The results show that food costs, convenience, healthiness, taste, and habits were frequently mentioned as determinants of food choice. However, the relative importance of these determinants seemed to be context-dependent. Interviewees generally had a positive attitude towards nudges, especially when they were aligned with product preferences, information needs, and beliefs about the food environment. Still, some interviewees also expressed distrust towards nudging strategies, suspecting ulterior motives. We conclude that nudging strategies should target foods which align with product preferences and information needs. However, the suspicion of ulterior motives highlights an important concern which should be considered when implementing supermarket-based nudging strategies.