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 Adults with a low socioeconomic position (SEP) are more likely to engage in unhealthy diets as compared to adults with high SEP. However, individual-level educational interventions aiming to improve food choices have shown limited effectiveness in adults with low SEP. Environmental-level interventions such as nudging strategies however, may be more likely to benefit low SEP groups. We aimed to review the evidence for the effectiveness of nudges as classified according to interventions in proximal physical micro-environments typology (TIPPME) to promote healthy purchases, food choice, or affecting energy intake or content of purchases, within real-life food purchasing environments. Second, we aimed to investigate the potentially moderating role of SEP. Methods We systematically searched PubMed, EMBASE, and PsycINFO until 31 January 2018. Studies were considered eligible for inclusion when they i) complied with TIPPME intervention definitions; ii) studied actual purchases, food choice, or energy intake or content of purchases, iii) and were situated in real-life food purchasing environments. Risk of bias was assessed using a quality assessment tool and evidence was synthesized using harvest plots. Results From the 9210 references identified, 75 studies were included. Studies were generally of weak to moderate quality. The most frequently studied nudges were information (56%), mixed (24%), and position nudges (13%). Harvest plots showed modest tendencies towards beneficial effects on outcomes for information and position nudges. Less evidence was available for other TIPPME nudging interventions for which the harvest plots did not show compelling patterns. Only six studies evaluated the effects of nudges across levels of SEP (e.g., educational level, food security status, job type). Although there were some indications that nudges were more effective in low SEP groups, the limited amount of evidence and different proxies of SEP used warrant caution in the interpretation of findings. Conclusions Information and position nudges may contribute to improving population dietary behaviours. Evidence investigating the moderating role of SEP was limited, although some studies reported greater effects in low SEP subgroups. We conclude that more high-quality studies obtaining detailed data on participant’s SEP are needed. Registration This systematic review is registered in the PROSPERO database (CRD42018086983).

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.

To study plasma and dietary linoleic acid (LA) in relation to type 2 diabetes risk in post-myocardial infarction (MI) patients. RESEARCH DESIGN AND METHODSWe included 3,257 patients aged 60-80 years (80% male) with a median time since MI of 3.5 years from the Alpha Omega Cohort and who were initially free of type 2 diabetes. At baseline (2002)(2003)(2004)(2005)(2006), plasma LA was measured in cholesteryl esters, and dietary LA was estimated with a 203-item food-frequency questionnaire. Incident type 2 diabetes was ascertained through self-reported physician diagnosis and medication use. Hazard ratios (with 95% CIs) were calculated by Cox regressions, in which dietary LA isocalorically replaced the sum of saturated (SFA) and trans fatty acids (TFA). RESULTSMean 6 SD circulating and dietary LA was 50.1 6 4.9% and 5.9 6 2.1% energy, respectively. Plasma and dietary LA were weakly correlated (Spearman r 5 0.13, P < 0.001). During a median follow-up of 41 months, 171 patients developed type 2 diabetes. Plasma LA was inversely associated with type 2 diabetes risk (quintile [Q]5 vs. Q1: 0.44 [0.26, 0.75]; per 5%: 0.73 [0.62, 0.86]). Substitution of dietary LA for SFA1TFA showed no association with type 2 diabetes risk (Q5 vs. Q1: 0.78 [0.36, 1.72]; per 5% energy: 1.18 [0.59, 2.35]). Adjustment for markers of de novo lipogenesis attenuated plasma LA associations. CONCLUSIONSIn our cohort of post-MI patients, plasma LA was inversely related to type 2 diabetes risk, whereas dietary LA was not related. Further research is needed to assess whether plasma LA indicates metabolic state rather than dietary LA in these patients.Dietary guidelines for the prevention of coronary heart disease promote the replacement of trans fatty acids (TFAs) and saturated fatty acids (SFAs) by cis unsaturated fat, especially polyunsaturated fatty acids (PUFAs) (1). Linoleic acid (LA; 18:2n-6) is the predominant type of dietary PUFA, with a contribution of 4-6% to total energy intake (% energy) in Western diets (2).

Objectives: To construct a diet-score measuring the level of adherence to the Healthy Reference Diet (HRD), to explore whether adherence to the HRD is associated with coronary heart disease (CHD), all-cause mortality risk, and to calculate its environmental impact. Design: Prospective cohort study. Setting: The Dutch contribution to the European Prospective Investigation into Cancer and Nutrition (EPIC-NL). Participants: 37,349 adults (20-70y) without CHD at baseline. Main outcome measures: Primary outcomes were incident CHD and all-cause mortality. Secondary outcomes were greenhouse gas emission (GHGE), land use, blue water use, freshwater eutrophication, marine eutrophication, and terrestrial acidification. Results: During a median 15.3-year follow-up, 2,543 cases of CHD occurred, and 5,648 individuals died from all causes. The average HRD-score was 73 (SD=10). High adherence to the HRD was associated with a 15% lower risk of CHD (hazard ratio 0.85, 95% confidence interval 0.75 to 0.96), as well as a 17% lower risk of all-cause mortality (hazard ratio 0.83, 95% confidence interval 0.77 to 0.90) in multivariable-adjusted models. Better adherence to the HRD was associated with lower environmental impact from GHGE (β= -0.10 kg CO2-eq, 95% confidence interval -0.13 to -0.07), land use (β= -0.11 m2 per year, 95% confidence interval -0.12 to -0.09), freshwater eutrophication (β= -0.000002 kg P-eq, 95% confidence interval -0.000004 to -0.000001), marine eutrophication (β= -0.00035 kg N-eq, 95% confidence interval -0.00042 to -0.00029), and terrestrial acidification (β = -0.004 kg SO2-eq, 95% confidence interval -0.004 to -0.003), but with higher environmental impact from blue water use (β=0.044 m3, 95% confidence interval 0.043 to 0.045). Conclusion: High adherence to the HRD was associated with lower risk of CHD and all-cause mortality. Additionally, increasing adherence to the HRD could lower some aspects of the environmental impact of diets, but attention is needed for the associated increase in blue water use.

Background Low socio-economic position is associated with consumption of lower quality diets, which may be partly explained by the cost of healthier diets. Therefore, we aimed to investigate the mediating role of dietary costs in the association between educational level and diet quality. Methods We used cross-sectional data from Dutch older adults ( N = 9399) in the EPIC-NL cohort. Participants provided information about their own and their partners’ highest attained educational level (as proxy for socio-economic position). Dietary behavior was assessed using a food frequency questionnaire from which we derived two diet-quality scores, including the Dutch Healthy Diet index 2015 (DHD15-index) and the Dietary Approaches to Stop Hypertension (DASH) diet. Dietary cost estimates were based on food price data from food stores, and linked to reported consumption of food items. Multiple regression analyses and bootstrapping were used examine the mediating role of dietary cost in the association between educational level and diet quality. Results Mean age of participants was 70 (SD: 10) years and 77% were women. Dietary costs significantly mediated the association between educational level and diet quality, except for high versus middle individual educational level and the DHD15-index. Depending on the dietary and educational indicator, dietary costs explained between 2 and 7% of the association between educational level and diet quality. Furthermore, associations were found to be modified by sex and age. For the DHD15-index, mediation effects were only present in females and adults older than 65 years, and for the DASH diet mediation effects were only present in females and strongest amongst adults older than 65 years compared to adults younger than 65 years. Conclusion Dietary costs seems to play a modest role in explaining educational differences in diet quality in an older Dutch population. Further research is needed to investigate which other factors may explain SEP differences in diet quality.

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.

Background The Healthy Reference Diet (HRD) was created to formulate dietary guidelines that would be healthy and sustainable. We aimed to construct a diet score measuring adherence to the HRD and to explore its association with cardiovascular events and environmental impact. Methods and Results We included 35 496 participants from the population‐based EPIC‐NL (European Prospective Investigation into Cancer and Nutrition‐Netherlands) study. HRD scores were calculated using data from food frequency questionnaires (0–140). Data on morbidity and mortality were retrieved through linkage with national and death registries. Data on environmental impact indicators were obtained from life cycle assessments. Associations between adherence to the HRD and cardiovascular events were estimated with Cox proportional hazard models. Linear regression analysis was conducted for the adherence to the HRD and each environmental indicator. High adherence to the HRD was associated with 14%, 12%, and 11% lower risks of cardiovascular disease (hazard ratio [HR] Q4vsQ1 , 0.86 [95% CI, 0.78–0.94]), coronary heart disease (HR Q4vsQ1 , 0.88 [95% CI, 0.78–1.00]), and total stroke (HR Q4vsQ1 , 0.89 [95% CI, 0.72–1.10]), respectively. High HRD adherence was associated with 2.4% (95% CI, −5.0 to 0.2) lower greenhouse gas emissions, 3.9% (95% CI, −5.2 to −2.6) less land use, 0.5% (95% CI, −2.6 to 1.6), less freshwater eutrophication, 3.3% (95% CI, −5.8 to −0.8), less marine eutrophication, 7.7% (95% CI, −10.8 to −4.6), less terrestrial acidification, and 32.1 % (95% CI, 28.5–35.7) higher blue water use. Conclusions High adherence to the HRD was associated with lower risk of cardiovascular disease, coronary heart disease, and modestly lower levels of most environmental indicators but a higher level of blue water use.