Effects of price discounts and tailored nutrition education on supermarket purchases: a randomized controlled trial

Strategies associated with improved healthiness of consumer purchasing in supermarket interventions: a systematic overview of reviews and evaluation of primary articles

Background

Growing evidence suggests that it is possible to change the retail food environment to enable healthier choices via in-store interventions. It has been difficult to draw clear conclusions as to which interventions are most effective in positively influencing consumer purchasing behaviour given the significant heterogeneity within the food retail research literature. The aim of this study was to (1) summarise current high-quality systematic, scoping, and/or narrative reviews (Part I: overview of reviews); and (2) synthesise high-quality original research, to understand the range, types and effectiveness of strategies implemented in food retail settings (Part II: evaluation of primary studies).

Methods

To identify reviews describing the effects of intervention strategies aiming to improve the healthiness of consumer purchasing in supermarkets, a systematic search across seven electronic databases was completed in April 2023. The methodological quality of reviews was assessed using the risk of bias in systematic reviews for systematic and scoping reviews, and the Scale for the Assessment of Narrative Review Articles for narrative reviews. High-quality reviews were further inspected and synthesised narratively (Part I). Next, to understand strategies associated with improved healthiness of consumer purchasing high-quality, primary articles from high-quality reviews identified in Part I were retrieved, and the strategies implemented within these interventions were summarised (Part II).

Results

Thirty-eight reviews met the inclusion criteria for Part I; two-thirds (n = 25, 66%) were rated as high-quality (66%). These reviews indicated that pricing strategies had the greatest proportion of reported positive or promising effects on outcomes (n = 8 of 11 reviews, 73%). Twenty reviews met the inclusion criteria for Part II and the 771 primary articles from these reviews were screened with 23 high-quality primary articles included in analysis. Findings indicated that promotional strategies in combination with another strategy appeared to be most successful among regular shoppers (the general population), whereas pricing was most successful in low socio-economic status and rural sub-groups.

Conclusion

Promotion, pricing and prompting were the most commonly tested strategies across the overview of reviews and review of primary articles. Promotion, in combination with other strategies, and pricing appear to be most promising, but the effectiveness of pricing strategies may vary by sub-groups of the population. How pricing and promotion in combination with other strategies can be implemented responsibly and sustainably to change purchase habits towards healthier items should be explored further.

Systematic Review registration

OSF, https://osf.io/jyg73/.

Impact of price reductions, subsidies, or financial incentives on healthy food purchases and consumption: a systematic review and meta-analysis

Poor diets are a global concern and are linked with various adverse health outcomes. Healthier foods such as fruit and vegetables are often more expensive than unhealthy options. This study aimed to assess the effect of price reductions for healthy food (including fruit and vegetables) on diet. We performed a systematic review and meta-analysis on studies that looked at the effects of financial incentives on healthy food. Main outcomes were change in purchase and consumption of foods following a targeted price reduction. We searched electronic databases (MEDLINE, EconLit, Embase, Cinahl, Cochrane Library, and Web of Science), citations, and used reference screening to identify relevant studies from Jan 1, 2013, to Dec 20, 2021, without language restrictions. We stratified results by population targeted (low-income populations vs general population), the food group that the reduction was applied to (fruit and vegetables, or other healthier foods), and study design. Percentage price reduction was standardised to assess the effect in meta-analyses. Study quality was assessed using the Cochrane Risk of Bias tool and Newcastle-Ottawa Scale. 34 studies were eligible; 15 took place in supermarkets and eight took place in workplace canteens in high-income countries, and 21 were targeted at socioeconomically disadvantaged communities. Pooled analyses of 14 studies showed a price reduction of 20% resulted in increases in fruit and vegetable purchases by 16·62% (95% CI 12·32 to 20·91). Few studies had maintained the price reduction for over 6 months. In conclusion, price reductions can lead to increases in purchases of fruit and vegetables, potentially sufficient to generate health benefits, if sustained.

Real-world nudging, pricing, and mobile physical activity coaching was insufficient to improve lifestyle behaviours and cardiometabolic health: the Supreme Nudge parallel cluster-randomised controlled supermarket trial

BACKGROUND

Context-specific interventions may contribute to sustained behaviour change and improved health outcomes. We evaluated the real-world effects of supermarket nudging and pricing strategies and mobile physical activity coaching on diet quality, food-purchasing behaviour, walking behaviour, and cardiometabolic risk markers.

METHODS

This parallel cluster-randomised controlled trial included supermarkets in socially disadvantaged neighbourhoods across the Netherlands with regular shoppers aged 30-80 years. Supermarkets were randomised to receive co-created nudging and pricing strategies promoting healthier purchasing (N = 6) or not (N = 6). Nudges targeted 9% of supermarket products and pricing strategies 3%. Subsequently, participants were individually randomised to a control (step counter app) or intervention arm (step counter and mobile coaching app) to promote walking. The primary outcome was the average change in diet quality (low (0) to high (150)) over all follow-up time points measured with a validated 40-item food frequency questionnaire at baseline and 3, 6, and 12 months. Secondary outcomes included healthier food purchasing (loyalty card-derived), daily step count (step counter app), cardiometabolic risk markers (lipid profile and HbA1c via finger prick, and waist circumference via measuring tape), and supermarket customer satisfaction (questionnaire-based: very unsatisfied (1) to very satisfied (7)), evaluated using linear mixed-models. Healthy supermarket sales (an exploratory outcome) were analysed via controlled interrupted time series analyses.

RESULTS

Of 361 participants (162 intervention, 199 control), 73% were female, the average age was 58 (SD 11) years, and 42% were highly educated. Compared to the control arm, the intervention arm showed no statistically significant average changes over time in diet quality (β - 1.1 (95% CI - 3.8 to 1.7)), percentage healthy purchasing (β 0.7 ( - 2.7 to 4.0)), step count (β - 124.0 (- 723.1 to 475.1), or any of the cardiometabolic risk markers. Participants in the intervention arm scored 0.3 points (0.1 to 0.5) higher on customer satisfaction on average over time. Supermarket-level sales were unaffected (β - 0.0 (- 0.0 to 0.0)).

CONCLUSIONS

Co-created nudging and pricing strategies that predominantly targeted healthy products via nudges were unable to increase healthier food purchases and intake nor improve cardiometabolic health. The mobile coaching intervention did not affect step count. Governmental policy measures are needed to ensure more impactful supermarket modifications that promote healthier purchases.

TRIAL REGISTRATION

Dutch Trial Register ID NL7064, 30 May 2018, https://www.onderzoekmetmensen.nl/en/trial/20990.

Improving economic access to healthy diets in first nations communities in high-income, colonised countries: a systematic scoping review

BACKGROUND

Affordability of healthy food is a key determinant of the diet-related health of First Nations Peoples. This systematic scoping review was commissioned by the Ngaanyatjarra Pitjantjatjara Yankunytjatjara Women's Council (NPYWC) in Central Australia to identify interventions to improve economic access to healthy food in First Nations communities in selected high-income, colonised countries.

METHODS

Eight databases and 22 websites were searched to identify studies of interventions and policies to improve economic access to healthy food in First Nations communities in Australia, Canada, the United States or New Zealand from 1996 to May 2022. Data from full text of articles meeting inclusion criteria were extracted to a spreadsheet. Results were collated by descriptive synthesis. Findings were examined with members of the NPYWC Anangu research team at a co-design workshop.

RESULTS

Thirty-five publications met criteria for inclusion, mostly set in Australia (37%) or the US (31%). Interventions (n = 21) were broadly categorised as price discounts on healthy food sold in communities (n = 7); direct subsidies to retail stores, suppliers and producers (n = 2); free healthy food and/or food vouchers provided to community members (n = 7); increased financial support to community members (n = 1); and other government strategies (n = 4). Promising initiatives were: providing a box of food and vouchers for fresh produce; prescriptions for fresh produce; provision/promotion of subsidised healthy meals and snacks in community stores; direct funds transfer for food for children; offering discounted healthy foods from a mobile van; and programs increasing access to traditional foods. Providing subsidies directly to retail stores, suppliers and producers was least effective. Identified enablers of effective programs included community co-design and empowerment; optimal promotion of the program; and targeting a wide range of healthy foods, particularly traditional foods where possible. Common barriers in the least successful programs included inadequate study duration; inadequate subsidies; lack of supporting resources and infrastructure for cooking, food preparation and storage; and imposition of the program on communities.

CONCLUSIONS

The review identified 21 initiatives aimed at increasing affordability of healthy foods in First Nations communities, of which six were deemed promising. Five reflected the voices and experiences of members of the NPYWC Anangu research team and will be considered by communities for trial in Central Australia. Findings also highlight potential approaches to improve economic access to healthy foods in First Nations communities in other high-income colonised countries.

TRIAL REGISTRATION

PROSPERO CRD42022328326.

Update on the Obesity Epidemic: After the Sudden Rise, Is the Upward Trajectory Beginning to Flatten?

PURPOSE OF REVIEW

To provide an update on current obesity prevalence trends and summarize the available evidence suggesting a possible plateau or stabilization in obesity rates after the previous sudden global rise.

RECENT FINDINGS

The escalating global obesity epidemic represents one of the most serious public health challenges. There have been some indications that in high-income populations, the rate of obesity increase in adults has been stabilized after the decade 2000-2010, suggesting a possible plateau. Current evidence also suggests that obesity rates have been stabilized in children and adolescents of most economically advanced countries since 2000, which is possibly related to healthier dietary habits and increased levels of physical activity. On the other hand, there is a steady uninterrupted rise in low-income nations, and the universal trend is obesity escalation rather than slowdown, mainly driven by sharp increases in the obesity prevalence of low-income populations. Furthermore, an increasing number of high- and middle-income countries are currently experiencing an epidemic of severe obesity. In high-income populations, severe obesity is expected to double its prevalence from 10 to 20% between 2020 and 2035, posing an enormous threat for healthcare systems. Even if transiently stabilized, the obesity prevalence remains globally at unacceptably high levels, and there is no guarantee that the current stability (if any) will be maintained for long. In this review, we explore the underlying drivers of the global obesity epidemic; we provide possible explanations for the reported slowdown of the obesity rates in some countries; and we overall take a critical perspective on the obesity plateau hypothesis, emphasizing the urgent need for immediate effective actions at population and regional level in order to halt the alarming obesity escalation and its serious health risks.

Behaviors Related to Limiting Fat Intake among Young Adults in Saudi Arabia

Young adults tend to frequently consume foods that are high in fat. Efforts to limit the consumption of fat among the Saudi population have been initiated; however, data concerning current behaviors related to limiting fat intake are lacking. We aimed to explore behaviors related to limiting fat intake and to investigate the association with fat intake among young adults in Saudi Arabia. In this cross-sectional study, a total of 305 students aged ≥19 years were recruited from Taibah University, Madinah. Face-to-face interviews were conducted to collect data concerning sociodemographic status, behaviors related to limiting fat intake, and fat intake. The median score of behaviors related to limiting fat intake was significantly higher among females and supplement users compared to other groups. Healthy weight, overweight, and obese students reported a significantly higher score of behaviors related to limiting fat intake, compared to underweight students. Males who reported making an effort to limit the consumption of fatty foods consumed less total fat, saturated fat, monounsaturated fat, and polyunsaturated fat, while those who reported reading the nutrition fact labels of food products consumed more polyunsaturated fat. Females who reported reading nutrition fact labels consumed less saturated fat. Efforts to limit fat intake have been noted especially among females; however, these efforts were not linked to fat intake among young adults in Saudi Arabia.

Poverty, price and preference barriers to improving diets in sub-Saharan Africa

Suboptimal diets are the most important preventable risk factor for the global burden of non-communicable diseases. The EAT-Lancet reference diet was therefore developed as a benchmark for gauging divergence from healthy eating standards. However, no previous research has comprehensively explored how and why this divergence exists in poorer countries undergoing nutrition transitions. This study therefore analyzes dietary patterns and drivers of the demand for nutritious foods using nationally representative household surveys from Ethiopia, Kenya, Tanzania, and Uganda. We show how barriers to dietary convergence stem from combinations of poverty, high relative food prices and weak preferences for some specific healthy foods. The article concludes by discussing interventions for strengthening consumer demand for healthy diets in Africa.

Participant Characteristics Associated with High Responsiveness to Personalized Healthy Food Incentives: a Secondary Analysis of the Randomized Controlled Crossover Smart Cart Study

BACKGROUND

Personalized dietary behavioral interventions could be enhanced by understanding factors accounting for individual variability in dietary decisions.

OBJECTIVE

This study was a secondary analysis of the Smart Cart randomized controlled trial to determine whether participant characteristics predicted high responsiveness to personalized grocery incentives for purchasing healthy food.

METHODS

This secondary analysis of a 9-mo crossover study included 192 regular shoppers (86%) from a Rhode Island supermarket. To analyze whether health, behavioral, and/or sociodemographic characteristics predicted responsiveness to a personalized grocery incentive intervention, participants were divided into 3 categories [high (n = 47), moderate (n = 50), and unresponsive (n = 95)] based on percentage changes in their Grocery Purchase Quality Index scores during the intervention versus control period calculated from sales data. We tested whether participant characteristics, including individual, household, and intervention-related factors, differed across responsiveness groups using ANOVA and whether they predicted the likelihood of being high responsive versus unresponsive or moderate responsive using logistic regression.

RESULTS

Participants had a mean (SD) age of 56.0 (13.8) y and were 89% female. Education, self-reported BMI, income, diet-related medical condition, food insecurity, cooking adequacy, and value consciousness differed across responsiveness categories (P < 0.1). High versus moderate and unresponsive participants increased their percentage of spending on targeted foods (P < 0.0001) and purchased fewer unique items (P = 0.01). In multinomial adjusted models, the odds of being high versus unresponsive or moderate responsive were lower for participants with a BMI (in kg/m2) <25 versus ≥25 (OR: 0.41; 95% CI: 0.19, 0.90) and higher with a diet-related medical condition present (OR: 3.75; 95% CI: 1.20, 11.8). Other characteristics were not associated with responsiveness.

CONCLUSIONS

Findings demonstrated that a BMI ≥25 and having a diet-related medical condition within the household predicted high responsiveness to a personalized grocery purchasing intervention, suggesting that personalized dietary interventions may be particularly effective for households with higher health risk. This trial is registered at www.clinicaltrials.gov as NCT03748056.

Healthy food prescription incentive programme for adults with type 2 diabetes who are experiencing food insecurity: protocol for a randomised controlled trial, modelling and implementation studies

INTRODUCTION

The high cost of many healthy foods poses a challenge to maintaining optimal blood glucose levels for adults with type 2 diabetes mellitus who are experiencing food insecurity, leading to diabetes complications and excess acute care usage and costs. Healthy food prescription programmes may reduce food insecurity and support patients to improve their diet quality, prevent diabetes complications and avoid acute care use. We will use a type 2 hybrid-effectiveness design to examine the reach, effectiveness, adoption, implementation and maintenance (RE-AIM) of a healthy food prescription incentive programme for adults experiencing food insecurity and persistent hyperglycaemia. A randomised controlled trial (RCT) will investigate programme effectiveness via impact on glycosylated haemoglobin (primary outcome), food insecurity, diet quality and other clinical and patient-reported outcomes. A modelling study will estimate longer-term programme effectiveness in reducing diabetes-related complications, resource use and costs. An implementation study will examine all RE-AIM domains to understand determinants of effective implementation and reasons behind programme successes and failures.

METHODS AND ANALYSIS

594 adults who are experiencing food insecurity and persistent hyperglycaemia will be randomised to a healthy food prescription incentive (n=297) or a healthy food prescription comparison group (n=297). Both groups will receive a healthy food prescription. The incentive group will additionally receive a weekly incentive (CDN$10.50/household member) to purchase healthy foods in supermarkets for 6 months. Outcomes will be assessed at baseline and follow-up (6 months) in the RCT and analysed using mixed-effects regression. Longer-term outcomes will be modelled using the UK Prospective Diabetes Study outcomes simulation model-2. Implementation processes and outcomes will be continuously measured via quantitative and qualitative data.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the University of Calgary and the University of Alberta. Findings will be disseminated through reports, lay summaries, policy briefs, academic publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT04725630.

PROTOCOL VERSION

Version 1.1; February 2022.

Understanding Whole Grain Consumption among Low-Income Older Adults Using the Theory of Planned Behavior

Older adults have low whole grain (WG) intake. This qualitative study used the Theory of Planned Behavior (TPB) to identify low-income older adults' WG beliefs. A convenience sample of 25 low-income adults 60 years and older were interviewed using questions developed based on TPB constructs: behavioral, normative, and control beliefs. Interviews were audio-recorded, transcribed verbatim, cross-checked for consistency, and analyzed using content analysis. Study results revealed that regarding behavioral beliefs, health benefits, taste, and nutrition were WG advantages and sensory qualities, higher cost, and longer cooking time were disadvantages. Regarding normative beliefs, healthcare professionals and family members approved WG intake and those less informed about WGs disapproved. Regarding control beliefs, availability/accessibility, knowledge of WG benefits, and WG cooking skills facilitated WG intake and age-related changes, WG cost, decreased motivation to cook, and low knowledge (label reading) were barriers. Results provide insights for developing programs to increase older adults' WG intake.

Estimating Dietary Intake from Grocery Shopping Data-A Comparative Validation of Relevant Indicators in Switzerland

In light of the globally increasing prevalence of diet-related chronic diseases, new scalable and non-invasive dietary monitoring techniques are urgently needed. Automatically collected digital receipts from loyalty cards hereby promise to serve as an objective and automatically traceable digital marker for individual food choice behavior and do not require users to manually log individual meal items. With the introduction of the General Data Privacy Regulation in the European Union, millions of consumers gained the right to access their shopping data in a machine-readable form, representing a historic chance to leverage shopping data for scalable monitoring of food choices. Multiple quantitative indicators for evaluating the nutritional quality of food shopping have been suggested, but so far, no comparison has validated the potential of these alternative indicators within a comparative setting. This manuscript thus represents the first study to compare the calibration capacity and to validate the discrimination potential of previously suggested food shopping quality indicators for the nutritional quality of shopped groceries, including the Food Standards Agency Nutrient Profiling System Dietary Index (FSA-NPS DI), Grocery Purchase Quality Index-2016 (GPQI), Healthy Eating Index-2015 (HEI-2015), Healthy Trolley Index (HETI) and Healthy Purchase Index (HPI), checking if any of them performs differently from the others. The hypothesis is that some food shopping quality indicators outperform the others in calibrating and discriminating individual actual dietary intake. To assess the indicators' potentials, 89 eligible participants completed a validated food frequency questionnaire (FFQ) and donated their digital receipts from the loyalty card programs of the two leading Swiss grocery retailers, which represent 70% of the national grocery market. Compared to absolute food and nutrient intake, correlations between density-based relative food and nutrient intake and food shopping data are stronger. The FSA-NPS DI has the best calibration and discrimination performance in classifying participants' consumption of nutrients and food groups, and seems to be a superior indicator to estimate nutritional quality of a user's diet based on digital receipts from grocery shopping in Switzerland.

Are nudging and pricing strategies on food purchasing behaviors equally effective for all? Secondary analyses from the Supreme Nudge virtual supermarket study

Nudging and pricing strategies are effective in promoting healthier purchases. However, whether the effects are equal across individuals with different personal characteristics is unknown. This exploratory study aimed to examine differential effects of nudging and pricing strategies on food purchases across individuals' levels of impulsivity, price sensitivity, decision-making styles, and food choice motives. Data from a virtual supermarket experiment where participants were exposed to five study conditions (control, nudging, pricing, salient pricing, and salient pricing with nudging) was used. Participants completed questionnaires assessing their impulsivity, price sensitivity, decision-making styles, and food choice motives. The outcome was the percentage of healthy food purchases. Effect modification was analyzed by adding interaction terms to the statistical models and post-hoc probing was conducted for statistically significant interaction terms. We used data from 400 Dutch adult participants (61.3% female, median age 30.0 years (IQR 24.0)). The effects of the nudging and pricing conditions on healthy food purchases were not modified by impulsivity, price sensitivity, decision-making styles, and the food choice motives 'health' and 'price'. Only the interactions of the food choice motive 'natural content of foods' x pricing (B = -1.02, 90%CI = -2.04; -0.01), the food choice motive 'weight control' x nudging (B = -2.15, 90%CI = -3.34; -0.95), and 'weight control' x pricing (B = -1.87, 90%CI = -3.11; -0.62) were statistically significant. Post-hoc probing indicated that nudging and/or pricing strategies were more effective in individuals who gave lower priority to these food choice motives. The effects of nudging and pricing strategies on increasing healthy food purchasing behaviors, at least in a virtual environment, do not seem to be influenced by personal characteristics and may therefore be implemented as general health promoting strategies.

A systematic review of supermarket automated electronic sales data for population dietary surveillance

Context

Most dietary assessment methods are limited by self-report biases, how long they take for participants to complete, and cost of time for dietitians to extract content. Electronically recorded, supermarket-obtained transactions are an objective measure of food purchases, with reduced bias and improved timeliness and scale.

Objective

The use, breadth, context, and utility of electronic purchase records for dietary research is assessed and discussed in this systematic review.

Data sources

Four electronic databases (MEDLINE, EMBASE, PsycINFO, Global Health) were searched. Included studies used electronically recorded supermarket transactions to investigate the diet of healthy, free-living adults.

Data extraction

Searches identified 3422 articles, of which 145 full texts were retrieved and 72 met inclusion criteria. Study quality was assessed using the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies.

Data analysis

Purchase records were used in observational studies, policy evaluations, and experimental designs. Nutrition outcomes included dietary patterns, nutrients, and food category sales. Transactions were linked to nutrient data from retailers, commercial data sources, and national food composition databases.

Conclusion

Electronic sales data have the potential to transform dietary assessment and worldwide understanding of dietary behavior. Validation studies are warranted to understand limits to agreement and extrapolation to individual-level diets.

Systematic Review Registration

PROSPERO registration no. CRD42018103470

Food promotions and the cost of a healthy diet

With approximately two in three UK adults overweight or obese, one in five living in poverty and our emergence from the Covid-19 pandemic with implications for employment and income status there is an urgent need to understand what it costs to eat healthily and the role that promotions can play in helping householders manage food budgets. The literature suggests that, in affluent countries, price promotions appear to increase consumer food purchases and are applied more frequently to less healthy products than their healthy counterparts. This review discusses the cost of a healthy diet, identifies the prevalence of promotions in both the supermarket setting generally and a typical shopping basket specifically, and discusses the barriers to affording a healthy diet. Given the current policy focus on the cost of living and population health emphasising the need for food shopping to represent health and value for money for better public health outcomes, this review contributes to the evidence base for retailers' and policymakers' consideration as policy solutions are sought to reduce population obesity levels, while ensuring the affordability and accessibility of nutritious food. It is important, given the shift in consumer purchasing behaviour to online shopping as a result of self-isolating or reticence to physically access stores in response to the Covid-19 pandemic, that retail food promotions are available irrespective of the chosen mode of shopping (in-store or online).

The Availability and Quality of Food Labelling Components in the Canadian E-Grocery Retail Environment

Background: Although packaged foods sold in retail stores must follow food labelling regulations, there are no e-grocery food labelling regulations to mandate and standardize the availability and presentation of product information. Therefore, the objective of the study was to evaluate the availability and quality of food labelling components in the Canadian e-grocery retail environment. Methods: A sample of fresh and pre-packaged products was identified on eight leading grocery retail websites in Canada, to assess the availability and quality of food labelling components. Results: Out of 555 product searches, all products were accompanied by product images with front-of-pack images more readily available (96.0%) than back-of-pack (12.4%) and other side panel images (3.1%). The following mandatory nutrition information was available for 61.1% of the products: nutrition facts table (68.8%), ingredient (73.9%), and allergen (53.8%) information. The majority of the nutrition information was available after scrolling down, clicking additionally on the description page, or viewing only as an image. Date markings were not available; packaging material information was available for 2.0% of the products. Conclusions: There was wide variability and inconsistencies in the presentation of food labelling components in the e-grocery retail environment, which can be barriers in enabling Canadians to make informed purchasing decisions.

Efficiency of In-Store Interventions to Impact Customers to Purchase Healthier Food and Beverage Products in Real-Life Grocery Stores: A Systematic Review and Meta-Analysis

Grocery stores are important settings to promote healthier food and beverage choices. The present paper aims at reviewing the effectiveness of different types of in-store interventions and how they impact sales of different product category in real grocery stores. Systematic search was conducted in six databases. In-store interventions were categorized according to the framework by Kraak et al. (2017) into one or more of eight interventions (e.g., place, profile, portion, pricing, promotion, healthy default picks, prompting and proximity). This systematic theme-based review follows the preferred reporting items for systematic reviews and meta-analyses (PRISMA) data screening and selection. Thirty-six studies were included in the qualitative synthesis and 30 studies were included in the meta-analysis, representing 72 combinations of in-store interventions. The analysis demonstrates that interventions overall had small significant effect size (ES) using Cohen's d on food purchase behavior (d = 0.17, 95% CI [0.04, 0.09]), with largest ES for pricing (d = 0.21) and targeting fruits and vegetables (d = 0.28). Analysis of ES of in-store interventions show that pricing, and pricing combined with promotion and prompting, effectively impacted purchase behavior. Interventions significantly impacted both sales of healthy and unhealthy products and significantly increased sales of fruits and vegetables, healthy beverage and total volume of healthy products. Results should however be interpreted with some caution, given the relatively low quality of overall evidence and low number of studies and observations for some types of intervention. Further research exploring impact on different in-store interventions and targeting especially unhealthy products are needed.

The 'Eat Well @ IGA' healthy supermarket randomised controlled trial: process evaluation

Background

Successful implementation and long-term maintenance of healthy supermarkets initiatives are crucial to achieving potential population health benefits. Understanding barriers and enablers of implementation of real-world trials will enhance wide-scale implementation. This process evaluation of a healthy supermarket intervention sought to describe (i) customer, retailer and stakeholder perspectives on the intervention; (ii) intervention implementation; and (iii) implementation barriers and enablers.

Methods

Eat Well @ IGA was a 12-month randomised controlled trial conducted in 11 Independent Grocers of Australia (IGA) chain supermarkets in regional Victoria, Australia (5 intervention and 6 wait-listed control stores). Intervention components included trolley and basket signage, local area and in-store promotion, and shelf tags highlighting the healthiest packaged foods. A sequential mixed-methods process evaluation was undertaken. Customer exit surveys investigated demographics, and intervention recall and perceptions. Logistic mixed-models estimated associations between customer responses and demographics, with store as random effect. Supermarket staff surveys investigated staff demographics, interactions with customers, and intervention component feedback. Semi-structured stakeholder interviews with local government, retail and academic partners explored intervention perceptions, and factors which enabled or inhibited implementation, maintenance and scalability. Interviews were inductively coded to identify key themes.

Results

Of 500 customers surveyed, 33%[95%CI:23,44] recalled the Eat Well @ IGA brand and 97%[95%CI:93,99] agreed that IGA should continue its efforts to encourage healthy eating. The 82 staff surveyed demonstrated very favourable intervention perceptions. Themes from 19 interviews included that business models favour sales of unhealthy foods, and that stakeholder collaboration was crucial to intervention design and implementation. Staff surveys and interviews highlighted the need to minimise staff time for project maintenance and to regularly refresh intervention materials to increase and maintain salience among customers.

Conclusions

This process evaluation found that interventions to promote healthy diets in supermarkets can be perceived as beneficial by retailers, customers, and government partners provided that barriers including staff time and intervention salience are addressed. Collaborative partnerships in intervention design and implementation, including retailers, governments, and academics, show potential for encouraging long-term sustainability of interventions.

Trial registration

ISRCTN, ISRCTN37395231 Registered 4 May 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01104-z.

Effect of Personalized Incentives on Dietary Quality of Groceries Purchased: A Randomized Crossover Trial

Importance

Many factors are associated with food choice. Personalized interventions could help improve dietary intake by using individual purchasing preferences to promote healthier grocery purchases.

Objective

To test whether a healthy food incentive intervention using an algorithm incorporating customer preferences, purchase history, and baseline diet quality improves grocery purchase dietary quality and spending on healthy foods.

Design, Setting, and Participants

This was a 9-month randomized clinical crossover trial (AB-BA) with a 2- to 4-week washout period between 3-month intervention periods. Participants included 224 loyalty program members at an independent Rhode Island supermarket who completed baseline questionnaires and were randomized from July to September 2018 to group 1 (AB) or group 2 (BA). Data analysis was performed from September 2019 to May 2020.

Intervention

Participants received personalized weekly coupons with nutrition education during the intervention period (A) and occasional generic coupons with nutrition education during the control period (B). An automated study algorithm used customer data to allocate personalized healthy food incentives to participant loyalty cards. All participants received a 5% grocery discount.

Main Outcomes and Measures

Grocery Purchase Quality Index-2016 (GPQI-16) scores (range, 0-75, with higher scores denoting healthier purchases) and percentage spending on targeted foods were calculated from cumulative purchasing data. Participants in the top and bottom 1% of spending were excluded. Paired t tests examined between-group differences.

Results

The analytical sample included 209 participants (104 in group 1 and 105 in group 2), with a mean (SD) age of 55.4 (14.0) years. They were predominantly non-Hispanic White (193 of 206 participants [94.1%]) and female (187 of 207 participants [90.3%]). Of 161 participants with income data, 81 (50.3%) had annual household incomes greater than or equal to $100 000. Paired t tests showed that the intervention increased GPQI-16 scores (between-group difference, 1.06; 95% CI, 0.27-1.86; P = .01) and percentage spending on targeted foods (between-group difference, 1.38%; 95% CI, 0.08%-2.69%; P = .04). During the initial intervention period, group 1 (AB) and group 2 (BA) had similar mean (SD) GPQI-16 scores (41.2 [6.6] vs 41.0 [7.5]) and mean (SD) percentage spending on targeted healthy foods (32.0% [10.8%] vs 31.0% [10.5%]). During the crossover intervention period, group 2 had a higher mean (SD) GPQI-16 score than group 1 (42.9 [7.7] vs 41.0 [6.8]) and mean (SD) percentage spending on targeted foods (34.0% [12.1%] vs 32.0% [13.1%]).

Conclusions and Relevance

This pilot trial demonstrated preliminary evidence for the effectiveness of a novel personalized healthy food incentive algorithm to improve grocery purchase dietary quality.

Trial Registration

ClinicalTrials.gov Identifier: NCT03748056.

Interventions to improve health literacy among Aboriginal and Torres Strait Islander Peoples: a systematic review

Background

Aboriginal and Torres Strait Islander peoples continue to experience poorer health outcomes than other population groups. While data specific to Indigenous Australians are scarce, a known social health literacy gradient exists linking low health literacy and poor health outcomes within many minority populations. Improving health literacy among Indigenous Australians is an important way to support self-determination and autonomy in both individuals and communities, by enhancing knowledge and improving health outcomes. This review aims to rigorously examine the effectiveness of health literacy interventions targeting Aboriginal and Torres Strait Islander peoples.

Methods

A systematic review across six databases (The Cochrane Library, PubMed, Embase, SCOPUS, ProQuest Dissertation and Thesis and Web of Science) was performed for publications evaluating interventions to improve health literacy among Indigenous Australian adults using search terms identifying a range of related outcomes.

Results

Of 824 articles retrieved, a total of five studies met the eligibility criteria and were included in this review. The included studies evaluated the implementation of workshops, structured exercise classes and the provision of discounted fruit and vegetables to improve nutrition, modify risk factors for chronic diseases, and improve oral health literacy. All interventions reported statistically significant improvement in at least one measured outcome. However, there was limited involvement of the Aboriginal and Torres Strait Islander community members in the research process and participant retention rates were sub-optimal.

Conclusion

There is limited evidence on interventions to improve health literacy in Indigenous Australian adults. Participation in interventions was often suboptimal and loss to follow-up was high. Future studies co-designed with Aboriginal and Torres Strait Islander community members are needed to improve health literacy in this population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10278-x.

The healthy food marketing strategies study: design, baseline characteristics, and supermarket compliance

Identifying effective strategies to promote healthy eating and reduce obesity is a priority in the USA, especially among low-income and minority groups, who often have less access to healthy food and higher rates of obesity. Efforts to improve food access have led to more supermarkets in low-income, ethnically diverse neighborhoods. However, this alone may not be enough to reduce food insecurity and improve residents' diet quality and health. This paper summarizes the design, methods, baseline findings, and supermarket in-store marketing strategy compliance for a randomized trial of the impact of healthy food marketing on the purchase of healthier "target" food items. Thirty-three supermarkets in low-income, high-minority neighborhoods in the metropolitan Philadelphia area were matched on store size and percentage of sales from government food assistance programs and randomly assigned to the intervention or control group. Healthy marketing strategies, including increased availability of healthier "target" products, prime shelf-placement and call-out promotion signs, and reduced availability of regular "comparison" products, were implemented in 16 intervention stores for an 18 month period for over 100 individual food items. Six product categories were studied: bread, checkout cooler beverages, cheese, frozen dinners, milk, and salty snacks. The primary outcome measure was weekly sales per store in each product category for 1 year preintervention and 18 months during the intervention. Compliance with the marketing strategies was assessed twice per month for the first 6 months and once a month thereafter. Store and neighborhood characteristics were not significantly different between control and intervention stores. Intercept surveys with customers to assess shopping habits and grocery marketing environment assessments to examine the food promotion environment were completed in the same six food categories. In intercept surveys, 51.0% of shoppers self-identified as overweight and 60.6% wanted to change their weight. Shoppers who typically purchased one type of food over another commonly did so out of habit or because the item was on sale. Findings revealed that preintervention sales of healthier "target" or regular "comparison" items did not differ between intervention and control stores for 1 year prior to intervention implementation. Rates of compliance with the healthy marketing strategies were high, averaging 76.5% over the first 12 months in all 16 stores. If healthy in-store marketing interventions are effective in this scaled-up, longer-term study, they should be translated into wider use in community supermarkets.

The Retail Food Sector and Indigenous Peoples in High-Income Countries: A Systematic Scoping Review

Indigenous Peoples in high-income countries experience higher burdens of food insecurity, obesity, and diet-related health conditions compared to national averages. The objective of this systematic scoping review is to synthesize information from the published literature on the methods/approaches, findings, and scope for research and interventions on the retail food sector servicing Indigenous Peoples in high-income countries. A structured literature search in two major international databases yielded 139 relevant peer-reviewed articles from nine countries. Most research was conducted in Oceania and North America, and in rural and remote regions. Several convergent issues were identified across global regions including limited grocery store availability/access, heightened exposure to unhealthy food environments, inadequate market food supplies (i.e., high prices, limited availability, and poor quality), and common underlying structural factors including socio-economic inequality and colonialism. A list of actions that can modify the nature and structure of retailing systems to enhance the availability, accessibility, and quality of healthful foods is identified. While continuing to (re)align research with community priorities, international collaboration may foster enhanced opportunities to strengthen the evidence base for policy and practice and contribute to the amelioration of diet quality and health at the population level.

Can Healthy Checkout Counters Improve Food Purchases? Two Real-Life Experiments in Dutch Supermarkets

Most snacks displayed at supermarket checkouts do not contribute to a healthy diet. We investigated the effects of introducing healthier snack alternatives at checkouts in supermarkets on purchasing behavior. In Study 1, we investigated the effect of completely substituting less healthy with healthier snacks (one supermarket). In Study 2, we investigated the effect of placing and discounting healthier snacks while the less healthy snacks remain in place (two supermarkets). In both studies, the number of purchased snacks (per 1000 customers) was used as the outcome variable. Results for Study 1 showed that the absolute number of purchased checkout snacks was 2.4 times lower (95% confidence interval (CI): 1.9-2.7) when healthier snacks instead of less healthy snacks were placed at the supermarket checkouts. Results for Study 2 showed that when additional healthier snacks were placed near the checkouts, the absolute number of healthier purchased snacks increased by a factor of 2.1 (95% CI: 1.3-3.3). When additional healthier snacks were placed near the checkouts and discounted, the absolute number of healthier purchased snacks increased by a factor of 2.7 (95% CI: 2.0-3.6), although this was not statistically significant higher than placement only (ratio: 1.1, 95% CI: 0.7-1.9). Purchases of less healthy snacks did not decline, and even slightly increased, during the intervention period (ratio: 1.3, 95% CI: 1.1-1.5). If supermarkets want to promote healthier snack purchases, additional healthier products can be positioned near the checkouts. However, this does not discourages the purchase of less healthy snacks. Therefore, to discourage unhealthy snack purchases at supermarket checkouts, a total substitution of less healthy snacks with healthier alternatives is most effective.

The drivers, trends and dietary impacts of non-nutritive sweeteners in the food supply: a narrative review

Poor diets, including excess added sugar consumption, contribute to the global burden of disease. Subsequently, many nutrition policies have been implemented to reduce added sugar intake and improve population health, including taxes, education, labelling and environmental interventions. A potential consequence of these policy actions is the substitution of added sugars with non-nutritive sweeteners (NNS) in a variety of foods and beverages. NNS are used to reduce the energy and sugar content of foods and beverages while maintaining their palatability. Evidence of the toxicological risks of NNS is inconsistent, though concerns have been raised over the potential substitution effects of ultra-processed foods containing NNS for whole foods. This review aimed to provide an overview of current NNS food supply and consumption patterns, assess added sugar-reduction policies and their impact on NNS, and determine the impact of NNS on food choice, energy intake and diet quality. NNS are widely available in a variety of products, though most commonly in carbonated beverages, dairy products, confectionery, table-top sweeteners and fruit drinks. However, the longitudinal trends of different product categories, and differences between geographies and economy-income levels, require further study. Few studies have examined NNS consumption trends globally, though an increase in NNS consumption in beverages has been observed in some regions. Research examining how the increased availability of low-sugar, NNS-containing products affects global dietary patterns is limited, particularly in terms of their potential substitution effects.

Evaluation of an intervention to provide brief support and personalized feedback on food shopping to reduce saturated fat intake (PC-SHOP): A randomized controlled trial

BACKGROUND

Guidelines recommend reducing saturated fat (SFA) intake to decrease cardiovascular disease (CVD) risk, but there is limited evidence on scalable and effective approaches to change dietary intake, given the large proportion of the population exceeding SFA recommendations. We aimed to develop a system to provide monthly personalized feedback and healthier swaps based on nutritional analysis of loyalty card data from the largest United Kingdom grocery store together with brief advice and support from a healthcare professional (HCP) in the primary care practice. Following a hybrid effectiveness-feasibility design, we tested the effects of the intervention on SFA intake and low-density lipoprotein (LDL) cholesterol as well as the feasibility and acceptability of providing nutritional advice using loyalty card data.

METHODS AND FINDINGS

The Primary Care Shopping Intervention for Cardiovascular Disease Prevention (PC-SHOP) study is a parallel randomized controlled trial with a 3 month follow-up conducted between 21 March 2018 to 16 January2019. Adults ≥18 years with LDL cholesterol >3 mmol/L (n = 113) were recruited from general practitioner (GP) practices in Oxfordshire and randomly allocated to "Brief Support" (BS, n = 48), "Brief Support + Shopping Feedback" (SF, n = 48) or "Control" (n = 17). BS consisted of a 10-minute consultation with an HCP to motivate participants to reduce their SFA intake. Shopping feedback comprised a personalized report on the SFA content of grocery purchases and suggestions for lower SFA swaps. The primary outcome was the between-group difference in change in SFA intake (% total energy intake) at 3 months adjusted for baseline SFA and GP practice using intention-to-treat analysis. Secondary outcomes included %SFA in purchases, LDL cholesterol, and feasibility outcomes. The trial was powered to detect an absolute reduction in SFA of 3% (SD3). Neither participants nor the study team were blinded to group allocation. A total of 106 (94%) participants completed the study: 68% women, 95% white ethnicity, average age 62.4 years (SD 10.8), body mass index (BMI) 27.1 kg/m2 (SD 4.7). There were small decreases in SFA intake at 3 months: control = -0.1% (95% CI -1.8 to 1.7), BS = -0.7% (95% CI -1.8 to 0.3), SF = -0.9% (95% CI -2.0 to 0.2); but no evidence of a significant effect of either intervention compared with control (difference adjusted for GP practice and baseline: BS versus control = -0.33% [95% CI -2.11 to 1.44], p = 0.709; SF versus control = -0.11% [95% CI -1.92 to 1.69], p = 0.901). There were similar trends in %SFA based on supermarket purchases: control = -0.5% (95% CI -2.3 to 1.2), BS = -1.3% (95% CI -2.3 to -0.3), SF = -1.5% (95% CI -2.5 to -0.5) from baseline to follow-up, but these were not significantly different: BS versus control p = 0.379; SF versus control p = 0.411. There were small reductions in LDL from baseline to follow-up (control = -0.14 mmol/L [95% CI -0.48, 0.19), BS: -0.39 mmol/L [95% CI -0.59, -0.19], SF: -0.14 mmol/L [95% CI -0.34, 0.07]), but these were not significantly different: BS versus control p = 0.338; SF versus control p = 0.790. Limitations of this study include the small sample of participants recruited, which limits the power to detect smaller differences, and the low response rate (3%), which may limit the generalisability of these findings.

CONCLUSIONS

In this study, we have shown it is feasible to deliver brief advice in primary care to encourage reductions in SFA intake and to provide personalized advice to encourage healthier choices using supermarket loyalty card data. There was no evidence of large reductions in SFA, but we are unable to exclude more modest benefits. The feasibility, acceptability, and scalability of these interventions suggest they have potential to encourage small changes in diet, which could be beneficial at the population level.

TRIAL REGISTRATION

ISRCTN14279335.

Impact of a Healthy Retail Intervention on Fruits and Vegetables and Total Sales in Tribally Owned Convenience Stores: Findings From the THRIVE Study

BACKGROUND

Healthy retail interventions are a recommended intervention strategy to address diet-related diseases, such as obesity and diabetes; however, retail managers are concerned about their bottom line. This study's aim was to assess the impact of a healthy retail intervention on fruits and vegetables (FV) sales, as well as total sales, in tribally owned convenience stores where grocery stores are scarce.

METHOD

We analyzed weekly sales data over the first 6 months of a healthy retail intervention. We assessed the proportion of sales from two FV baskets. The FV basket included all fresh, canned, and dried FV sold at stores; while the fruits, vegetables, and salads (FVS) basket included all FV items as well as all salads sold. We compared mean weekly sales rates in intervention and control stores over the 6-month period using generalized estimating equations models to account for repeated measures.

RESULTS

Mean weekly FV basket sales rates were higher in intervention stores than control stores in both Nations. Mean weekly FVS baskets sales were significantly higher in intervention stores than control stores in one Nation and were higher, but not statistically significant, in intervention stores in the other Nation. Total sales remained steady throughout the intervention period.

CONCLUSIONS

The THRIVE (Tribal Health and Resilience in Vulnerable Environments) intervention increased FV sales without negatively affecting total sales. Policy and Practice Implications. Healthy retail interventions in tribal convenience stores, where many Native Americans living in rural areas shop due to scarcity of grocery stores, could improve diet-related disparities without reducing total sales.

The effect of a shelf placement intervention on sales of healthier and less healthy breakfast cereals in supermarkets: A co-designed pilot study

Supermarkets are the principal source of grocery food in many high-income countries. Choice architecture strategies show promise to improve the healthiness of food choices. A retailer-academic collaboration was formed to co-design and pilot selected commercially sustainable strategies to increase sales of healthier foods relative to less healthy foods in supermarkets. Two co-design workshops, involving supermarket corporate staff and public health nutrition academics, identified potential interventions. One intervention, more prominent shelf placement of healthier products within one category (breakfast cereals), was selected for testing. A pilot study (baseline, intervention and follow-up, 12-weeks each) was undertaken in six supermarkets (three intervention and three control) in Auckland, New Zealand. Products were ranked by nutrient levels and profile, and after accounting for the supermarkets' space management principles, healthier products were placed at adult eye level. The primary outcome was change in sales of healthier products relative to total category sales. Secondary outcomes were nutrient profile of category sales, in-store product promotions, customer perceptions, and retailer feedback. There was no difference in proportional sales of more prominently positioned healthier products between intervention (56%) and control (56%) stores during the intervention. There were no differences in the nutrient profile of category sales. A higher proportion of less healthy breakfast cereals were displayed in intervention versus control stores (57% vs 43%). Most customers surveyed supported shelf placement as a strategy (265, 88%) but noted brand preferences and price were more salient determinants of purchases. Retailers were similarly supportive but balancing profit, health/nutrition and customer satisfaction was challenging. Shelf placement alone was not an effective strategy to increase purchases of healthier breakfast cereals. This study showed co-design of a healthy eating intervention with a commercial retailer is feasible, but concurrent retail environment factors likely limited the public health impact of the intervention.

To what extent do dietary costs explain socio-economic differences in dietary behavior?

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.

Environmental Interventions to Reduce the Consumption of Sugar-Sweetened Beverages: Abridged Cochrane Systematic Review

BACKGROUND

Regular consumption of sugar-sweetened beverages (SSB) can increase the risk for obesity, type 2 diabetes, cardiovascular disease, and dental caries. Interventions that alter the physical or social environment in which individuals make beverage choices have been proposed to reduce the consumption of SSB.

METHODS

We included randomised controlled, non-randomised controlled, and interrupted time series studies on environmental interventions, with or without behavioural co-interventions, implemented in real-world settings, lasting at least 12 weeks, and including at least 40 individuals. Studies on the taxation of SSB were not included, as these are subject of a separate Cochrane review. We used standard Cochrane methods for data extraction, risk of bias assessment, and evidence grading and synthesis. Searches were updated to January 24, 2018.

RESULTS

We identified 14,488 unique records and assessed 1,030 full texts for eligibility. We included 58 studies comprising a total of 1,180,096 participants and a median length of follow-up of 10 months. We found moderate-certainty evidence for consistent associations with decreases in SSB consumption or sales for the following interventions: traffic light labelling, price increases on SSB, in-store promotion of healthier beverages in supermarkets, government food benefit programs with incentives for purchasing fruits and vegetables and restrictions on SSB purchases, multi-component community campaigns focused on SSB, and interventions improving the availability of low-calorie beverages in the home environment. For the remaining interventions we found low- to very-low-certainty evidence for associations showing varying degrees of consistency.

CONCLUSIONS

With observed benefits outweighing observed harms, we suggest that environmental interventions to reduce the consumption of SSB be considered as part of a wider set of measures to improve population-level nutrition. Implementation should be accompanied by evaluations using appropriate methods. Future studies should examine population-level effects of interventions suitable for large-scale implementation, and interventions and settings not yet studied thoroughly.

Community-based interventions to increase dairy intake in healthy populations: a systematic review

Background

Considering the low frequency of dairy intake in the population, interventions aiming to increase its consumption can be a priority for any health system.

Objective

This study aims to summarize community-based interventions for improving dairy consumption and their effectiveness to help policy-makers in designing coherent public health strategies.

Methods

This study was conducted in 2019, using PubMed/MEDLINE, Scopus, EMBASE, Cochrane Library, Web of Science, ProQuest, and Google Scholar. Two independent reviewers selected the eligible studies, and the outcomes of interest were extracted. The quality of eligible studies was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for randomized controlled trials and quasi-experimental studies.

Results

Out of 521 initially identified articles, 25 studies were included. Interventions reported in 19 studies were effective in increasing dairy consumption. Interventions in high-income countries were more effective than those in middle- and low-income countries. Interventions in health centers and supermarkets were more effective than the community and school-level interventions. Interventions in supermarkets and adolescents as target groups were more effective than children, middle-aged people, and the elderly. Also, educational interventions and changing buying/selling pattern were more effective than multiple interventions. Interventions longer than 24 and 48 weeks were more effective than shorter interventions.

Conclusion

Three policy options including educational interventions, multiple interventions, and changing the purchase pattern are suggested. It seems that applying all of the interventions together can be more effective. Also, long-term and well-designed future studies in different settings are recommended to confirm these results.

Reducing cardiometabolic risk in adults with a low socioeconomic position: protocol of the Supreme Nudge parallel cluster-randomised controlled supermarket trial

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.

Methods

The Supreme Nudge trial includes nudging and pricing strategies cluster-randomised on the supermarket level, with: i) control group receiving no intervention; ii) group 1 receiving healthy food nudges (e.g., product placement or promotion); iii) group 2 receiving nudges and pricing strategies (taxing of unhealthy foods and subsidizing healthy foods). In collaboration with a Dutch supermarket chain we will select nine stores located in low SEP neighbourhoods, with the nearest competitor store at > 1 km distance and managed by a committed store manager. Across the clusters, a personalized mobile coaching app targeting walking behaviour will be randomised at the individual level, with: i) control group; ii) a group receiving the mobile PA app. All participants (target n = 1485) should be Dutch-speaking, aged 45–75 years with a low SEP and purchase more than half of their household grocery shopping at the selected supermarkets. Participants will be recruited via advertisements and mail-invitations followed by community-outreach methods. Primary outcomes are changes in systolic blood pressure, LDL-cholesterol, HbA1c and dietary intake after 12 months follow-up. Secondary outcomes are changes in diastolic blood pressure, blood lipid markers, waist circumference, steps per day, and behavioural factors including healthy food purchasing, food decision style, social cognitive factors related to nudges and to walking behaviours and customer satisfaction after 12 months follow-up. The trial will be reflexively monitored to support current and future implementation.

Discussion

The findings can guide future research and public health policies on reducing lifestyle-related health inequalities, and contribute to a supermarket-based health promotion intervention implementation roadmap.

Trial registration

Dutch Trial Register ID NL7064, 30th of May, 2018

Modelling the health impact of food taxes and subsidies with price elasticities: The case for additional scaling of food consumption using the total food expenditure elasticity

Background

Food taxes and subsidies are one intervention to address poor diets. Price elasticity (PE) matrices are commonly used to model the change in food purchasing. Usually a PE matrix is generated in one setting then applied to another setting with differing starting consumptions and prices of foods. This violates econometric assumptions resulting in likely mis-estimation of total food consumption. In this paper we demonstrate this problem, canvass possible options for rescaling all consumption after applying a PE matrix, and illustrate the use of a total food expenditure elasticity (TFEe; the expenditure elasticity for all food combined given the policy-induced change in the total price of food). We use case studies of: NZ$2 per 100g saturated fat (SAFA) tax, NZ$0.4 per 100g sugar tax, and a 20% fruit and vegetable (F&V) subsidy.

Methods

We estimated changes in food purchasing using a NZ PE matrix applied conventionally, and then with TFEe adjustment. Impacts were quantified for pre- to post-policy changes in total food expenditure and health adjusted life years (HALYs) for the total NZ population alive in 2011 over the rest of their lifetime using a multistate lifetable model.

Results

Two NZ studies gave TFEe’s of 0.68 and 0.83, with international estimates ranging from 0.46 to 0.90 (except a UK outlier of 0.04). Without TFEe adjustment, total food expenditure decreased with the tax policies and increased with the F&V subsidy–implausible directions of shift given economic theory and the external TFEe estimates. After TFEe adjustment, HALY gains reduced by a third to a half for the two taxes and reversed from an apparent health loss to a health gain for the F&V subsidy. With TFEe adjustment, HALY gains (in 1000’s) were: 1,805 (95% uncertainty interval 1,337 to 2,340) for the SAFA tax; 1,671 (1,220 to 2,269) for the sugar tax; and 953 (453 to 1,308) for the F&V subsidy.

Conclusions

If PE matrices are applied in settings beyond where they were derived, additional scaling is likely required. We suggest that the TFEe is a useful scalar, but we also encourage other researchers to examine this issue and propose alternative options.

Sacco S, L. Pomeranz J. Marketing to Children in Supermarkets: An Opportunity for Public Policy to Improve Children's Diets

Public health experts worldwide are calling for a reduction of the marketing of nutrient-poor food and beverages to children. However, industry self-regulation and most government policies do not address in-store marketing, including shelf placement and retail promotions. This paper reports two U.S.-based studies examining the prevalence and potential impact of in-store marketing for nutrient-poor child-targeted products. Study 1 compares the in-store marketing of children's breakfast cereals with the marketing of other (family/adult) cereals, including shelf space allocation and placement, special displays and promotions, using a national audit of U.S. supermarkets. Child-targeted cereals received more shelf space, middle- and lower-shelf placements, special displays, and promotions compared with other cereals. Study 2 compares the proportion of product sales associated with in-store displays and promotions for child-targeted versus other fruit drinks/juices, using syndicated sales data. A higher proportion of child-targeted drink sales were associated with displays and promotions than sales of other drinks. In both categories, the results were due primarily to major company products. Although in-store marketing of child-targeted products likely appeals to both children and parents, these practices encourage children's consumption of nutrient-poor food and drinks. If companies will not voluntarily address in-store marketing to children, government policy options are available to limit the marketing of unhealthy foods in the supermarket.

Competing teammates: food in New Zealand sports settings

Despite the global popularity of sport, we know surprisingly little about food in sports settings. This two-phased study analysed the foods available in New Zealand sports settings. Phase one included a systematic literature review and 18 interviews with key informants from national and regional sporting organizations. Phase two involved 37 key informant interviews with stakeholders from two exemplar sports, rugby and netball and direct observations at netball and rugby venues. This study found most foods and beverages at New Zealand sports events were energy-dense and nutrient-poor. Caterers' control over food provision, socio-cultural attitudes which view unhealthy foods as normal, and a dominant profit motive, appear to be the key factors influencing the food environment in sports settings. Food environments in sport settings provide frequent opportunities to purchase and consume energy-dense, nutrient-poor foods. The research shows we have competing players in the sports context-unhealthy food and healthy physical activity. Achieving sustainable healthy change in sports settings will be challenging when the prevailing attitude normalizes the unhealthy environment. Nutrition policies in sports clubs are urgently needed to increase the availability of healthy food. This requires support from health agencies and leadership from national sports organizations. Given the international nature of the food industry and sport, these findings from New Zealand may assist other countries to better understand the nature of food in sport and adopt appropriate interventions to reduce the obesogenic environment that is sport.

A Systematic Review of the Effect of Retail Food Environment Interventions on Diet and Health with a Focus on the Enabling Role of Public Policies

PURPOSE OF REVIEW

Update the state of evidence on the effectiveness of retail food environment interventions in influencing diet and explore the underlying role of public policy, through a systematic review of population-level interventions to promote health in the retail food environment, including community and consumer environments. Diet-related outcomes included purchasing, dietary intakes, diet quality, and health including weight. We coded studies for enabling public policy levers underpinning the intervention, using two widely used conceptual frameworks.

RECENT FINDINGS

Of 86 articles (1974-2018), the majority (58 articles, 67%) showed at least one positive effect on diet. Thirteen articles (15%) discussed natural experiments, 27 articles (31%) used a design involving comparison groups including 23 articles (27%) specifically describing randomized controlled trials, and 46 (53%) were quasi-experimental (cross-sectional) evaluations. Across the "4Ps" of marketing (product, promotion, placement, and price), promotion comprised the greatest proportion of intervention strategies, especially in earlier literature (pre-2008). Few studies combined geographic access interventions with 4P strategies, and few used robust dietary intake assessments. Behavior change communication remains an intervention mainstay, but recent work has also incorporated environmental and social planning, and fiscal strategies. More recent interventions were multi-component. The retail food environment intervention literature continues to grow and has become more robust overall, with clearer evidence of the effect of interventions on diet-related outcomes, including consumer purchasing, dietary intakes, and health. There is still much scope for development in the field. Attention to enabling public policy could help to strengthen intervention implementation and evaluation in the retail food environment.

Investigating business outcomes of healthy food retail strategies: A systematic scoping review

Large changes to food retail settings are required to improve population diet. However, limited research has comprehensively considered the business implications of healthy food retail strategies for food retailers. We performed a systematic scoping review to identify types of business outcomes that have been reported in healthy food retail strategy evaluations. Peer-reviewed and grey literature were searched. We identified qualitative or quantitative real-world food or beverage retail strategies designed to improve the healthiness of the consumer nutrition environment (eg, changes to the "marketing mix" of product, price, promotion, and/or placement). Eligible studies reported store- or chain-level outcomes for measures of commercial viability, retailer perspectives, customer perspectives, and/or community outcomes. 11 682 titles and abstracts were screened with 107 studies included for review from 15 countries. Overall item sales, revenue, store patronage, and customer level of satisfaction with strategy were the most frequently examined outcomes. There was a large heterogeneity in outcome measures reported and in favourability for retailers of outcomes across studies. We recommend more consistent reporting of business outcomes and increased development and use of validated and reliable measurement tools. This may help generate more robust research evidence to aid retailers and policymakers to select feasible and sustainable healthy food retail strategies to benefit population health within and across countries.

Environmental interventions to reduce the consumption of sugar-sweetened beverages and their effects on health

BACKGROUND

Frequent consumption of excess amounts of sugar-sweetened beverages (SSB) is a risk factor for obesity, type 2 diabetes, cardiovascular disease and dental caries. Environmental interventions, i.e. interventions that alter the physical or social environment in which individuals make beverage choices, have been advocated as a means to reduce the consumption of SSB.

OBJECTIVES

To assess the effects of environmental interventions (excluding taxation) on the consumption of sugar-sweetened beverages and sugar-sweetened milk, diet-related anthropometric measures and health outcomes, and on any reported unintended consequences or adverse outcomes.

SEARCH METHODS

We searched 11 general, specialist and regional databases from inception to 24 January 2018. We also searched trial registers, reference lists and citations, scanned websites of relevant organisations, and contacted study authors.

SELECTION CRITERIA

We included studies on interventions implemented at an environmental level, reporting effects on direct or indirect measures of SSB intake, diet-related anthropometric measures and health outcomes, or any reported adverse outcome. We included randomised controlled trials (RCTs), non-randomised controlled trials (NRCTs), controlled before-after (CBA) and interrupted-time-series (ITS) studies, implemented in real-world settings with a combined length of intervention and follow-up of at least 12 weeks and at least 20 individuals in each of the intervention and control groups. We excluded studies in which participants were administered SSB as part of clinical trials, and multicomponent interventions which did not report SSB-specific outcome data. We excluded studies on the taxation of SSB, as these are the subject of a separate Cochrane Review.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened studies for inclusion, extracted data and assessed the risks of bias of included studies. We classified interventions according to the NOURISHING framework, and synthesised results narratively and conducted meta-analyses for two outcomes relating to two intervention types. We assessed our confidence in the certainty of effect estimates with the GRADE framework as very low, low, moderate or high, and presented 'Summary of findings' tables.

MAIN RESULTS

We identified 14,488 unique records, and assessed 1030 in full text for eligibility. We found 58 studies meeting our inclusion criteria, including 22 RCTs, 3 NRCTs, 14 CBA studies, and 19 ITS studies, with a total of 1,180,096 participants. The median length of follow-up was 10 months. The studies included children, teenagers and adults, and were implemented in a variety of settings, including schools, retailing and food service establishments. We judged most studies to be at high or unclear risk of bias in at least one domain, and most studies used non-randomised designs. The studies examine a broad range of interventions, and we present results for these separately.Labelling interventions (8 studies): We found moderate-certainty evidence that traffic-light labelling is associated with decreasing sales of SSBs, and low-certainty evidence that nutritional rating score labelling is associated with decreasing sales of SSBs. For menu-board calorie labelling reported effects on SSB sales varied.Nutrition standards in public institutions (16 studies): We found low-certainty evidence that reduced availability of SSBs in schools is associated with decreased SSB consumption. We found very low-certainty evidence that improved availability of drinking water in schools and school fruit programmes are associated with decreased SSB consumption. Reported associations between improved availability of drinking water in schools and student body weight varied.Economic tools (7 studies): We found moderate-certainty evidence that price increases on SSBs are associated with decreasing SSB sales. For price discounts on low-calorie beverages reported effects on SSB sales varied.Whole food supply interventions (3 studies): Reported associations between voluntary industry initiatives to improve the whole food supply and SSB sales varied.Retail and food service interventions (7 studies): We found low-certainty evidence that healthier default beverages in children's menus in chain restaurants are associated with decreasing SSB sales, and moderate-certainty evidence that in-store promotion of healthier beverages in supermarkets is associated with decreasing SSB sales. We found very low-certainty evidence that urban planning restrictions on new fast-food restaurants and restrictions on the number of stores selling SSBs in remote communities are associated with decreasing SSB sales. Reported associations between promotion of healthier beverages in vending machines and SSB intake or sales varied.Intersectoral approaches (8 studies): We found moderate-certainty evidence that government food benefit programmes with restrictions on purchasing SSBs are associated with decreased SSB intake. For unrestricted food benefit programmes reported effects varied. We found moderate-certainty evidence that multicomponent community campaigns focused on SSBs are associated with decreasing SSB sales. Reported associations between trade and investment liberalisation and SSB sales varied.Home-based interventions (7 studies): We found moderate-certainty evidence that improved availability of low-calorie beverages in the home environment is associated with decreased SSB intake, and high-certainty evidence that it is associated with decreased body weight among adolescents with overweight or obesity and a high baseline consumption of SSBs.Adverse outcomes reported by studies, which may occur in some circumstances, included negative effects on revenue, compensatory SSB consumption outside school when the availability of SSBs in schools is reduced, reduced milk intake, stakeholder discontent, and increased total energy content of grocery purchases with price discounts on low-calorie beverages, among others. The certainty of evidence on adverse outcomes was low to very low for most outcomes.We analysed interventions targeting sugar-sweetened milk separately, and found low- to moderate-certainty evidence that emoticon labelling and small prizes for the selection of healthier beverages in elementary school cafeterias are associated with decreased consumption of sugar-sweetened milk. We found low-certainty evidence that improved placement of plain milk in school cafeterias is not associated with decreasing sugar-sweetened milk consumption.

AUTHORS' CONCLUSIONS

The evidence included in this review indicates that effective, scalable interventions addressing SSB consumption at a population level exist. Implementation should be accompanied by high-quality evaluations using appropriate study designs, with a particular focus on the long-term effects of approaches suitable for large-scale implementation.

Nutrition literacy predicts adherence to healthy/unhealthy diet patterns in adults with a nutrition-related chronic condition

OBJECTIVE

To describe the relationship between adherence to distinct dietary patterns and nutrition literacy.

DESIGN

We identified distinct dietary patterns using principal covariates regression (PCovR) and principal components analysis (PCA) from the Diet History Questionnaire II. Nutrition literacy was assessed using the Nutrition Literacy Assessment Instrument (NLit). Cross-sectional relationships between dietary pattern adherence and global and domain-specific NLit scores were tested by multiple linear regression. Mean differences in diet pattern adherence among three predefined nutrition literacy performance categories were tested by ANOVA.

SETTING

Metropolitan Kansas City, USA.

PARTICIPANTS

Adults (n 386) with at least one of four diet-related diseases.

RESULTS

Three diet patterns of interest were derived: a PCovR prudent pattern and PCA-derived Western and Mediterranean patterns. After controlling for age, sex, BMI, race, household income, education level and diabetes status, PCovR prudent pattern adherence positively related to global NLit score (P &lt; 0·001, β = 0·36), indicating more intake of prudent diet foods with improved nutrition literacy. Validating the PCovR findings, PCA Western pattern adherence inversely related to global NLit (P = 0·003, β = -0·13) while PCA Mediterranean pattern positively related to global NLit (P = 0·02, β = 0·12). Using predefined cut points, those with poor nutrition literacy consumed more foods associated with the Western diet (fried foods, sugar-sweetened beverages, red meat, processed foods) while those with good nutrition literacy consumed more foods associated with prudent and Mediterranean diets (vegetables, olive oil, nuts).

CONCLUSIONS

Nutrition literacy predicted adherence to healthy/unhealthy diet patterns. These findings warrant future research to determine if improving nutrition literacy effectively improves eating patterns.

A Pilot Randomized Controlled Trial of a Digital Intervention Aimed at Improving Food Purchasing Behavior: The Front-of-Pack Food Labels Impact on Consumer Choice Study

BACKGROUND

Most food in the United Kingdom is purchased in supermarkets, and many of these purchases are routinely tracked through supermarket loyalty card data. Using such data may be an effective way to develop remote public health interventions and to measure objectively their effectiveness at changing food purchasing behavior.

OBJECTIVE

The Front-of-pack food Labels: Impact on Consumer Choice (FLICC) study is a pilot randomized controlled trial of a digital behavior change intervention. This pilot trial aimed to collect data on recruitment and retention rates and to provide estimates of effect sizes for the primary outcome (healthiness of ready meals and pizzas purchased) to inform a larger trial.

METHODS

The intervention consisted of a website where participants could access tailored feedback on previous purchases of ready meals and pizzas, set goals for behavior change, and model and practice the recommended healthy shopping behavior using traffic light labels. The control consisted of Web-based information on traffic light labeling. Participants were recruited via email from a list of loyalty card holders held by the participating supermarket. All food and drink purchases for the participants for the 6 months before recruitment, during the 6-week intervention period, and during a 12-week washout period were transferred to the research team by the participating supermarket. Healthiness of ready meals and pizzas was measured using a predeveloped scale based solely on the traffic light colors on the foods. Questionnaires were completed at recruitment, end of the intervention, and end of washout to estimate the effect of the intervention on variables that mediate behavior change (eg, belief and intention formation).

RESULTS

We recruited 496 participants from an initial email to 50,000 people. Only 3 people withdrew from the study, and purchase data were received for all other participants. A total of 208 participants completed all 3 questionnaires. There was no difference in the healthiness of purchased ready meals and pizzas between the intervention and control arms either during the intervention period (P=.32) or at washout (P=.59).

CONCLUSIONS

Although the FLICC study did not find evidence of an impact of the intervention on food purchasing behavior, the unique methods used in this pilot trial are informative for future studies that plan to use supermarket loyalty card data in collaboration with supermarket partners. The experience of the trial showcases the possibilities and challenges associated with the use of loyalty card data in public health research.

TRIAL REGISTRATION

ISRCTN Registry ISRCTN19316955; http://www.isrctn.com/ISRCTN19316955 (Archived by WebCite at http://www.webcitation.org/76IVZ9WjK).

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1186/s40814-015-0015-1.

Healthy food marketing and purchases of fruits and vegetables in large grocery stores

Healthy food marketing in the retail environment can be an important driver of fruit and vegetable purchases. In Los Angeles County, the Nutrition Education and Obesity Prevention (NEOP) program utilized this strategy to promote healthy eating among low-income families that shop at large retail chain stores. The present study assessed whether self-reported exposure to large retail NEOP interventions, including seeing at least one store visual, watching an in-store cooking demonstration, and/or seeing at least one program advertisement, were associated with increased fruit and vegetable purchases. During fall 2014, the Division of Chronic Disease and Injury Prevention in the Los Angeles County Department of Public Health partnered with Samuels Center to conduct store patron intercept surveys at six large food retail stores participating in NEOP across Los Angeles County. Of 1050 participants who completed the survey, almost a quarter (25.0%) reported seeing at least one visual throughout the store and 9.2% watched a cooking demonstration. Seeing at least one visual and watching a cooking demonstration were not significantly associated with percent dollars spent on fruits and vegetables each week. Among participants who reported being exposed to at least one store visual, those enrolled in the Supplemental Nutrition Assistance Program (SNAP) reported spending 6% more on fruits and vegetables than those who were not enrolled (p = 0.046). Although the NEOP store interventions did not individually increase store purchases, their educational value may still influence patron food selection, especially if coupled to the monetary resources of SNAP for those who are enrolled.

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Seeing a store visual was not associated with percent dollars spent on produce.

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Of those who saw a visual, females spent more on fruits and vegetables than males.

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SNAP enrollees spent 6% more than non-enrollees on produce.

Examination of how food environment and psychological factors interact in their relationship with dietary behaviours: test of a cross-sectional model

BACKGROUND

To improve population diet environmental strategies have been hailed the panacea because they require little agency or investment of personal resources; this contrasts with conventional strategies that rely on individuals to engage high levels of agency and make deliberate choices. There is an immediate need to improve understanding of the synergy between the psychological and environmental determinants of diet in order to optimise allocation of precious public health resources. This study examined the synergistic and relative association between a number of food environment and psychological factors and the dietary behaviours of a population sample of women with young children.

METHODS

Women in Hampshire were recruited from children's centres and asked about their demographic characteristics, psychological resources, dietary behaviours (food frequency questionnaire) and perceptions of healthy food access and affordability. Three local food environment factors were objectively assessed: i) spatial access to food outlets using activity spaces; ii) healthfulness of the supermarket where women did their main food shop, (based on nine in-store factors including price, placement and promotion on seven healthy and five less healthy foods); iii) nutrition environment of children's centres visited frequently by the women, assessed via staff-administered questionnaire. A theoretical model linking environmental factors to dietary behaviours, both directly and indirectly through three factors representing individual agency (psychological resources, perceived food affordability, perceived food accessibility), was tested using Structural Equation Modelling.

RESULTS

Complete data were available for 753 women. The environment of women's main supermarket was indirectly related to their dietary behaviours through psychological resources and perceived food affordability. Shopping at supermarkets classified as having a healthier in-store environment was associated with having greater psychological resources associated with healthy eating (standardised regression weight β = 0.14SD, p = 0.03) and fewer food affordability concerns (β = - 0.14SD, p = 0.01), which in turn related to healthier dietary behaviours (β = 0.55SD, < 0.001 and β = - 0.15, p = 0.01 respectively). The three food environment factors were not directly associated with dietary behaviour (p > 0.3). The overall model fit was good (CFI = 0.91, RMSEA = 0.05 [0.05, 0.06]).

CONCLUSIONS

This pathway analysis identified three focal points for intervention and suggests that high-agency interventions targeting individual psychological resources when combined with low-agency supermarket environment interventions may confer greater benefits on dietary behaviours than either intervention alone.

Being Motivated by Nutrition Is Associated With Healthy Home Food Environment of Supplemental Nutrition Assistance Program (SNAP) Recipients

OBJECTIVE

To examine the relationship between food shopping motivating factors and the home food environment (HFE).

METHODS

Participants in the Supplemental Nutrition Assistance Program (n = 123) who were taking part in the Utah State Double-Up Food Bucks evaluation program were interviewed about their HFE, factors motivating shopping, and food security status. Composite HFE scores were derived from the Perceived Nutrition Environment Measure Survey questionnaire and food security score from the 6-item US Household Food Security Survey questionnaire. Analysis included multiple linear regression.

RESULTS

Mean age was 46 ± 16.1 years. Regression models showed significant associations of being motivated by nutrition, education, and food security with HFE (β = 4.70, P = .03; β = 1.44, P = .06; and β = 1.44, P = .06, respectively).

CONCLUSION AND IMPLICATIONS

In-store interventions to improve perceived nutrition importance among shoppers may be a useful tool to improve home food supplies. Further research is recommended examining the association between food shopping motivators and the HFE in a larger population.

Optimising swaps to reduce the salt content of food purchases in a virtual online supermarket: A randomised controlled trial

Background

Offering consumers the opportunity to swap to lower-salt foods while shopping has potential to reduce salt intake. Offering a wider range of alternatives which are much lower in salt could increase the magnitude of salt reduction gained but may interfere with consumers’ engagement and willingness to accept swaps.

Objectives

To compare the salt reduction from offering swaps to a similar product but with minimally less salt to offering swaps with a substantial salt reduction including a range of alternative foods.

Methods

In an experimental, randomised trial conducted in a virtual online supermarket, participants with high blood pressure were asked to buy 12 items of food. One group was offered similar alternatives with 5–20% less salt (LS swaps); and the other group was offered these LS swaps and alternatives with >20% less salt (MLS swaps). The primary outcome was the change in salt density of the shopping basket (g/100g) from initially selected items, to the final items chosen.

Results

947 participants completed the task and were included in the analysis. There was a significant reduction in salt content of the final selected shopping basket in both groups; with a significantly greater reduction in the group offered LS + MLS swaps (−0.09g/100g, 95% C.I. −0.10, −0.07; p < 0.001). The proportion of swaps accepted was the same in both groups and the mean salt reduction per swap accepted in the group offered LS + MLS swaps was more than double that of the group offered LS swaps alone. 30% of MLS swaps accepted were from a different food subcategory.

Conclusions

Offering alternative products with a large reduction in salt, including potentially dissimilar products, does not decrease acceptability and leads to significantly greater reductions in the salt content of the shopping basket.

Trial registration

ISRCTN, ISRCTN91306993. Registered 5th February 2018 – retrospectively registered. https://www.isrctn.com/ISRCTN91306993.

Large-scale loyalty card data in health research

Objective

To study the characteristics of large-scale loyalty card data obtained in Finland, and to evaluate their potential and challenges in health research.

Methods

We contacted the holders of a certain loyalty card living in a specific region in Finland via email, and requested their electronic informed consent to obtain their basic background characteristics and grocery expenditure data from 2016 for health research purposes. Non-participation and the characteristics and expenditure of the participants were mainly analysed using summary statistics and figures.

Results

The data on expenditure came from 14,595 (5.6% of those contacted) consenting loyalty card holders. A total of 68.5% of the participants were women, with an average age of 46 years. Women and residents of Helsinki were more likely to participate. Both young and old participants were underrepresented in the sample. We observed that annual expenditure represented roughly two-thirds of the nationally estimated annual averages. Customers and personnel differed in their characteristics and expenditure, but not so much in their most frequently bought items.

Conclusions

Loyalty card data from a major retailer enabled us to reach a large, heterogeneous sample with fewer resources than conventional surveys of the same magnitude. The potential of the data was great because of their size, coverage, objectivity, and long periods of dynamic data collection, which enables timely investigations. The challenges included bias due to non-participation, purchases in other stores, the level of detail in product grouping, and the knowledge gaps in what is being consumed and by whom. Loyalty card data are an underutilised resource in research, and could be used not only in retailers’ activities, but also for societal benefit.

Appraisal of short and long versions of the Nutrition Environment Measures Survey (NEMS-S and NEMS-R) in Australia

OBJECTIVE

Research has begun to take a more ecological view of eating behaviour, examining multiple levels of influence: personal, social and environmental. The food environment is a major influence on eating behaviour, attracting the attention of researchers who have measured it in a number of ways. The present paper examines the short-form version, in comparison to the long-form version, of the Nutrition Environment Measures Survey (NEMS) - an observational food outlet audit tool.

DESIGN

Both the short-form and long-form were examined to qualitatively appraise the dimensions of the food environment assessed by each measure. Data from 135 food outlets in Australia were then used to compare results obtained using the short-form with the results from the long-form method, to consider the utility of the short-form measure.

SETTING

The retail food environment in Australia.ParticipantsOne hundred and thirty-five food outlets in Australia.

RESULTS

Results indicate that the short-form predominantly assessed availability of healthful foods (one aspect of the food environment). Several critical dimensions of the food environment known to influence eating behaviour were not assessed. For this data set, the short-form produced scores inconsistent with the longer version of the measure, delivering inflated estimates for stores and deflated estimates for restaurants.

CONCLUSIONS

Scores between the long-form and short-form versions were not comparable in this Australian study. Further development of food environment measures is recommended and must balance instrument brevity with the need to accurately capture important aspects of the food environment known to influence eating behaviour.

The cost-effectiveness of a 20% price discount on fruit, vegetables, diet drinks and water, trialled in remote Australia to improve Indigenous health

This paper estimates the cost-effectiveness of a 20% price discount on healthy food and beverages with and without consumer nutrition education, as trialled in remote Northern Australia. Changes in actual store sales, from the pre-discount baseline period, were analysed for population impact on consumption of fruit and vegetables, water and artificially sweetened soft drinks, in addition with total dietary weight (grams), energy (Mega Joules), and sodium (milligrams). Disability Adjusted Life Years (DALYs), arising from changes in dietary risk factor prevalence in the population, were estimated as the primary health outcome in a multi health-state Markov model. The costs of the strategies were sourced from paid invoices and time estimates of staff providing store-based discount promotion and consumer education. The incremental cost-effectiveness ratio adopted a partial societal perspective, (including health and retail sector costs), as cost per DALY averted and was presented in 2011 Australian dollars. The price discount, helped address a gap in food price equity for residents of remote communities. However, the discount strategy, with or without consumer education led to a net loss of population health –36 95%CI (-47,-25) or -21(-28, -15) DALYs respectively, at increased cost to the retail and health sectors, of AUD860000 95%CI (710000, 1million) or AUD500000 (410000, 590000). The strategies trialled were thereby categorised as dominated by current practice while acknowledging considerable uncertainty surrounding the health outcome estimates. The 20% discount on limited targeted products appeared to need to be considered in conjunction with other marketing strategies to support healthy food choices, if remote Australian Indigenous population health is to be improved.

Supermarket retailers' perspectives on healthy food retail strategies: in-depth interviews

BACKGROUND

Excess calorie consumption and poor diet are major contributors to the obesity epidemic. Food retailers, in particular at supermarkets, are key shapers of the food environment which influences consumers' diets. This study seeks to understand the decision-making processes of supermarket retailers-including motivators for and barriers to promoting more healthy products-and to catalogue elements of the complex relationships between customers, suppliers, and, supermarket retailers.

METHODS

We recruited 20 supermarket retailers from a convenience sample of full service supermarkets and national supermarket chain headquarters serving low- and high-income consumers in urban and non-urban areas of New York. Individuals responsible for making in-store decisions about retail practices engaged in online surveys and semi-structured interviews. We employed thematic analysis to analyze the transcripts.

RESULTS

Supermarket retailers, mostly representing independent stores, perceived customer demand and suppliers' product availability and deals as key factors influencing their in-store practices around product selection, placement, pricing, and promotion. Unexpectedly, retailers expressed a high level of autonomy when making decisions about food retail strategies. Overall, retailers described a willingness to engage in healthy food retail and a desire for greater support from healthy food retail initiatives.

CONCLUSIONS

Understanding retailers' in-store decision making will allow development of targeted healthy food retail policy approaches and interventions, and provide important insights into how to improve the food environment.