Improving Cardiovascular Health through Nudging Healthier Food Choices: A Systematic Review

Nudging Health Behavior Change Among Home-Based Cardiac Rehabilitation Patients: A Scoping Review

Background

In home-based cardiac rehabilitation practices, nudging has emerged and was actively explored to promote health behavior change among patients with heart disease. The literature on nudging strategy is fragmented and lacks comprehensive reviews.

Objective

This study aimed to identify nudging interventions to promote health behavior change among patients undergoing home-based cardiac rehabilitation, focusing on the scope, characteristics and delivery.

Methods

A scoping review was conducted from July to September 2023, during which databases including PubMed, Web of Science, and OVID (Embase, Cochrane Library, JBI) were searched. Search terms were constructed based on population-concept-context mnemonics approach. Reviewers screened articles independently and reviewed the included articles to extract key information about each nudge intervention.

Results

In included 25 studies, the majority (n=21) with the nudging strategy had positive results. 14 nudge strategies were identified and coded with the primary objective of changing health behaviors. The most common nudging strategy was goal setting, followed by feedback, and reminders and alerts. To capture the heterogeneity of nudging strategies, two independent dimensions were introduced to further classify them into four quadrants (active vs passive and synchronous vs passive). For example, some nudging strategies usually occur when the target behavior must be performed (synchronization) and requires the immediate participation of the home-based cardiac rehabilitation patients (active). In addition, digital nudging technology with gamification elements may become the mainstream in future research.

Conclusion

These studies reflected different objectives and implement nudging strategies in different ways. Despite the multiple nudging strategies are widely adopted, identifying the contributing components remains challenging.

Effectiveness of an online food shopping intervention to reduce salt purchases among individuals with hypertension - findings of the SaltSwitch Online Grocery Shopping (OGS) randomised trial

BACKGROUND

Online grocery shopping is a growing source of food purchases in many countries. We investigated the effect of nudging consumers towards purchases of lower sodium products using a web browser extension.

METHODS

This trial was conducted among individuals with hypertension who shopped for their groceries online in Australia. From July 2021 to June 2023, participants were randomised to use the SaltSwitch Online Grocery Shopping web browser extension or continue their usual grocery shopping for 12 weeks. The SaltSwitch extension modified a retailer's online shopping interface to suggest similar but lower sodium alternative products to those initially selected. The primary outcome was the difference in mean sodium density (mg sodium per 1000 kcal of energy) of packaged food purchases between the intervention and control groups.

RESULTS

We randomised 185 participants of average age 56.0 (SD 11.0) years. Most were women (64%), White (89%), had BMI > 25 kg/m2 (91%), and were taking anti-hypertensive medication (83%). Demographic and medical characteristics were similar across the randomised groups. 182 (98%) completed the trial. Over the 12-week intervention, the sodium density of groceries purchased by the intervention group compared to the control group was 204 mg/1000 kcal lower (95%CI, -352 to -56) (P = 0.01). The reduction in sodium density of purchases was apparent in weeks 1-4 and sustained through the end of the trial. 86% of participants in the intervention group made at least one switch to a lower sodium product. There were no detectable effects on blood pressure, spot urine sodium concentration, or other secondary outcomes across the 12-week study period.

CONCLUSIONS

Online shopping platforms provide a novel opportunity to support purchases of lower sodium foods. While the reductions in sodium density of purchases were moderate in size, population health benefits could nonetheless be large if they were sustained over time and at scale, with large and growing numbers of online grocery shoppers and a high prevalence of elevated blood pressure amongst adults.

TRIAL REGISTRATION

ACTRN12621000642886.

Positive serial dependence in ratings of food images for appeal and calories

Food is fundamental to survival, and our brains are highly attuned to rapidly process food stimuli. Neural signals show that foods can be discriminated as edible or inedible as early as 85 ms after stimulus onset,1 distinguished as processed or unprocessed beginning at 130 ms,2 and as high or low density from 165 ms.3 Recent evidence revealed specialized processing of food stimuli in the ventral visual pathway,4,5,6 an area that underlies perception of faces and other important objects. For many visual objects, perception can be biased toward recent perceptual history (known as serial dependence7,8). We examined serial dependence for food in two large samples (n > 300) who rated sequences of food images for either "appeal" or "calories." Ratings for calories were highly correlated between participants and were similar for males and females. Appeal ratings varied considerably between participants, consistent with the idiosyncratic nature of food preferences, and tended to be higher for males than females. High-calorie ratings were associated with high appeal, especially in males. Importantly, response biases showed clear positive serial dependences: higher stimulus values in the previous trials led to positive biases, and vice versa. The effects were similar for males and females and for calories and appeal ratings and were remarkably consistent across participants. These findings square with recently found food selectively in the visual temporal cortex, reveal a new mechanism influencing food decision-making, and suggest a new sensory-level component that could complement cognitive strategies in diet intervention.

Nudging Public Health Behaviors to Prevent COVID-19: A Systematic Review

Many countries have implemented strict preventive measures and mandatory policies to curb virus transmission during the COVID-19 pandemic. Some have adopted softer approaches, such as nudge-based intervention, to influence public health behavior. This systematic review, conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 guidelines, aims to determine if the nudge-based intervention can effectively influence people's preventive behavior during the early period of the COVID-19 pandemic. The review indicated an overall positive outcome, but results were mixed as nudge-based interventions substantially depended on the situational context. While the review found that the nudging technique that presents and conveys decision-related information was essential to nudging people, a secondary nudge would often applied to deliver the interventions. In addition, there was no indication of an ideal nudge technique that would be effective in most situations. Conversely, our findings indicate that the nudge would likely suffer from habituation after repeated intervention or backfire due to inappropriate use of nudges. Also, the ceiling effect would inhibit any nudge influences regardless of the technique(s) used. In sum, the results and the applicability of nudge-based interventions were mixed, highlighting the need for further research to advance the theory and practical developments.

Review on Emerging Therapeutic Strategies for Managing Cardiovascular Disease

Cardiovascular disease (CVD) remains a foremost global health concern, necessitating ongoing exploration of innovative therapeutic strategies. This review surveys the latest developments in cardiovascular therapeutics, offering a comprehensive overview of emerging approaches poised to transform disease management. The examination begins by elucidating the current epidemiological landscape of CVD and the economic challenges it poses to healthcare systems. It proceeds to scrutinize the limitations of traditional therapies, emphasizing the need for progressive interventions. The core focus is on novel pharmacological interventions, including advancements in drug development, targeted therapies, and repurposing existing medications. The burgeoning field of gene therapy and its potential in addressing genetic predispositions to cardiovascular disorders are explored, alongside the integration of artificial intelligence and machine learning in risk assessment and treatment optimization. Non-pharmacological interventions take center stage, with an exploration of digital health technologies, wearable devices, and telemedicine as transformative tools in CVD management. Regenerative medicine and stem cell therapies, offering promises of tissue repair and functional recovery, are investigated for their potential impact on cardiac health. This review also delves into the interplay of lifestyle modifications, diet, exercise, and behavioral changes, emphasizing their pivotal role in cardiovascular health and disease prevention. As precision medicine gains prominence, this synthesis of emerging therapeutic modalities aims to guide clinicians and researchers in navigating the dynamic landscape of cardiovascular disease management, fostering a collective effort to alleviate the global burden of CVD and promote a healthier future.

Effects of Using a Perforated Spoon on Salt Reduction When Consuming Ramen Noodles: A Randomized Crossover Study of Japanese Male University Students

Salt reduction is a public health priority for the Japanese population. We focused on the effect of salt reduction by changing eating utensils to reduce salt consumption. As a test meal, we used ramen, which is commonly eaten by Japanese individuals and has a high salt content. In this randomized crossover study, we hypothesized that eating ramen with a perforated spoon would reduce the quantity of ramen soup and salt consumed compared to using a regular spoon without holes. Soup intake, after-meal fullness, and deliciousness were compared between eating with chopsticks and a regular spoon, and with chopsticks and a perforated spoon. In total, 36 male university students (mean age, 20.7 [standard deviation, 1.8] years) were included in the analyses. The median salt intake (25th and 75th percentiles) was significantly lower with perforated spoons (1.8 [1.5, 4.3] g) than with regular spoons (2.4 [1.8, 4.8] g; p = 0.019). There were no significant differences in after-meal fullness or deliciousness for both spoon conditions (p > 0.05). For young men, the soup intake when eating ramen with a perforated spoon was lower than that with a regular spoon; this suggests a reduction in salt intake.

Matching, behavioral economics, and teleological behaviorism: Final cause analysis of substance use and health behavior

Howard Rachlin and his contemporaries pioneered basic behavioral science innovations that have been usefully applied to advance understanding of human substance use disorder and related health behaviors. We briefly summarize the innovations of molar behaviorism (the matching law), behavioral economics, and teleological behaviorism. Behavioral economics and teleological behaviorism's focus on final causes are especially illuminating for these applied fields. Translational and applied research are summarized for laboratory studies of temporal discounting and economic demand, cohort studies of alcohol and other drug use in the natural environment, and experimental behavioral economic modeling of health behavior-related public health policies. We argue that the teleological behavioral perspective on health behavior is conducive to and merges seamlessly with the contemporary socioecological model of health behavior, which broadens the contextual influences (e.g., community, economic, infrastructure, health care access and policy) of individuals' substance use and other health risk behaviors. Basic-to-applied translations to date have been successful and bode well for continued applications of basic science areas pioneered by Howard Rachlin and his contemporaries.

Using nudges to promote clinical decision making of healthcare professionals: A scoping review

Nudging has been discussed in the context of policy and public health, but not so much within healthcare. This scoping review aimed to assess the empirical evidence on how nudging techniques can be used to affect the behavior of healthcare professionals (HCPs) in clinical settings. A systematic database search was conducted for the period January 2010-December 2020 using the PRISMA extension for Scoping Review checklist. Two reviewers independently screened each article for inclusion. Included articles were reviewed to extract key information about each intervention, including purpose, target behavior, measured outcomes, key findings, nudging strategies, intervention objectives and their theoretical underpinnings. Two independent dimensions, building on Kahneman's System 1 and System 2, were used to describe nudging strategies according to user action and timing of their implementation. Of the included 51 articles, 40 reported statistically significant results, six were not significant and two reported mixed results. Thirteen different nudging strategies were identified aimed at modifying four types of HPCs' behavior: prescriptions and orders, procedure, hand hygiene, and vaccination. The most common nudging strategy employed were defaults or pre-orders, followed by alerts or reminders, and active choice. Many interventions did not require any deliberate action from users, here termed passive interventions, such as automatically changing prescriptions to their generic equivalent unless indicated by the user. Passive nudges may be successful in changing the target outcome but may go unnoticed by the user. Future work should consider the broader ethical implications of passive nudges.

Protocol for a novel sodium and blood pressure reduction intervention targeting online grocery shoppers with hypertension - the SaltSwitch Online Grocery Shopping randomized trial

BACKGROUND

High dietary sodium intake is a leading cause of hypertension. A major source of dietary sodium is salt added to processed food products available in retail food environments. The fast-growing online grocery shopping setting provides new opportunities for salt reduction interventions that support consumers in choosing healthier options.

METHODS

The SaltSwitch Online Grocery Shopping randomized controlled trial is investigating the feasibility, acceptability, and effectiveness of a novel intervention for lowering salt consumption and blood pressure amongst people with hypertension who shop for groceries online. The intervention is based on a bespoke web browser extension that interfaces with a major retailer's online store to highlight and interpret product sodium content and suggest similar but lower-sodium alternatives. The primary outcome of interest is change in mean systolic blood pressure between individuals randomized (1:1) to the intervention and control (usual online shopping) arms at 12 weeks. Secondary outcomes are diastolic blood pressure, spot urinary sodium and sodium:potassium ratio, sodium purchases, and dietary intake. Intervention implementation and lessons for future uptake will be assessed using a mixed methods process evaluation. Participants with hypertension who shop online for groceries and exhibit high sodium purchasing behavior are being recruited across Australia. A target sample size of 1,966 provides 80% power (2-sided alpha = 0.05) to detect a 2 mm Hg difference in systolic blood pressure between groups, assuming a 15 mm Hg standard deviation, after allowing for a 10% dropout rate.

DISCUSSION

This trial will provide evidence on an innovative intervention to potentially reduce salt intake and blood pressure in people with hypertension. The intervention caters to individual preferences by encouraging sustainable switches to similar but lower-salt products. If effective, the intervention will be readily scalable at low cost by interfacing with existing online retail environments.

Designing Persuasive Food Conversational Recommender Systems With Nudging and Socially-Aware Conversational Strategies

Unhealthy eating behavior is a major public health issue with serious repercussions on an individual’s health. One potential solution to overcome this problem, and help people change their eating behavior, is to develop conversational systems able to recommend healthy recipes. One challenge for such systems is to deliver personalized recommendations matching users’ needs and preferences. Beyond the intrinsic quality of the recommendation itself, various factors might also influence users’ perception of a recommendation. In this paper, we present Cora, a conversational system that recommends recipes aligned with its users’ eating habits and current preferences. Users can interact with Cora in two different ways. They can select pre-defined answers by clicking on buttons to talk to Cora or write text in natural language. Additionally, Cora can engage users through a social dialogue, or go straight to the point. Cora is also able to propose different alternatives and to justify its recipes recommendation by explaining the trade-off between them. We conduct two experiments. In the first one, we evaluate the impact of Cora’s conversational skills and users’ interaction mode on users’ perception and intention to cook the recommended recipes. Our results show that a conversational recommendation system that engages its users through a rapport-building dialogue improves users’ perception of the interaction as well as their perception of the system. In the second evaluation, we evaluate the influence of Cora’s explanations and recommendation comparisons on users’ perception. Our results show that explanations positively influence users’ perception of a recommender system. However, comparing healthy recipes with a decoy is a double-edged sword. Although such comparison is perceived as significantly more useful compared to one single healthy recommendation, explaining the difference between the decoy and the healthy recipe would actually make people less likely to use the system.

OUP accepted manuscript

The increasing volume and richness of healthcare data collected during routine clinical practice have not yet translated into significant numbers of actionable insights that have systematically improved patient outcomes. An evidence-practice gap continues to exist in healthcare. We contest that this gap can be reduced by assessing the use of nudge theory as part of clinical decision support systems (CDSS). Deploying nudges to modify clinician behaviour and improve adherence to guideline-directed therapy represents an underused tool in bridging the evidence-practice gap. In conjunction with electronic health records (EHRs) and newer devices including artificial intelligence algorithms that are increasingly integrated within learning health systems, nudges such as CDSS alerts should be iteratively tested for all stakeholders involved in health decision-making: clinicians, researchers, and patients alike. Not only could they improve the implementation of known evidence, but the true value of nudging could lie in areas where traditional randomized controlled trials are lacking, and where clinical equipoise and variation dominate. The opportunity to test CDSS nudge alerts and their ability to standardize behaviour in the face of uncertainty may generate novel insights and improve patient outcomes in areas of clinical practice currently without a robust evidence base.

Impact of color-coded and warning nutrition labelling schemes: A systematic review and network meta-analysis

BACKGROUND

Suboptimal diets are a leading risk factor for death and disability. Nutrition labelling is a potential method to encourage consumers to improve dietary behaviour. This systematic review and network meta-analysis (NMA) summarises evidence on the impact of colour-coded interpretive labels and warning labels on changing consumers' purchasing behaviour.

METHODS AND FINDINGS

We conducted a literature review of peer-reviewed articles published between 1 January 1990 and 24 May 2021 in PubMed, Embase via Ovid, Cochrane Central Register of Controlled Trials, and SCOPUS. Randomised controlled trials (RCTs) and quasi-experimental studies were included for the primary outcomes (measures of changes in consumers' purchasing and consuming behaviour). A frequentist NMA method was applied to pool the results. A total of 156 studies (including 101 RCTs and 55 non-RCTs) nested in 138 articles were incorporated into the systematic review, of which 134 studies in 120 articles were eligible for meta-analysis. We found that the traffic light labelling system (TLS), nutrient warning (NW), and health warning (HW) were associated with an increased probability of selecting more healthful products (odds ratios [ORs] and 95% confidence intervals [CIs]: TLS, 1.5 [1.2, 1.87]; NW, 3.61 [2.82, 4.63]; HW, 1.65 [1.32, 2.06]). Nutri-Score (NS) and warning labels appeared effective in reducing consumers' probability of selecting less healthful products (NS, 0.66 [0.53, 0.82]; NW,0.65 [0.54, 0.77]; HW,0.64 [0.53, 0.76]). NS and NW were associated with an increased overall healthfulness (healthfulness ratings of products purchased using models such as FSAm-NPS/HCSP) by 7.9% and 26%, respectively. TLS, NS, and NW were associated with a reduced energy (total energy: TLS, -6.5%; NS, -6%; NW, -12.9%; energy per 100 g/ml: TLS, -3%; NS, -3.5%; NW, -3.8%), sodium (total sodium/salt: TLS, -6.4%; sodium/salt per 100 g/ml: NS: -7.8%), fat (total fat: NS, -15.7%; fat per 100 g/ml: TLS: -2.6%; NS: -3.2%), and total saturated fat (TLS, -12.9%; NS: -17.1%; NW: -16.3%) content of purchases. The impact of TLS, NS, and NW on purchasing behaviour could be explained by improved understanding of the nutrition information, which further elicits negative perception towards unhealthful products or positive attitudes towards healthful foods. Comparisons across label types suggested that colour-coded labels performed better in nudging consumers towards the purchase of more healthful products (NS versus NW: 1.51 [1.08, 2.11]), while warning labels have the advantage in discouraging unhealthful purchasing behaviour (NW versus TLS: 0.81 [0.67, 0.98]; HW versus TLS: 0.8 [0.63, 1]). Study limitations included high heterogeneity and inconsistency in the comparisons across different label types, limited number of real-world studies (95% were laboratory studies), and lack of long-term impact assessments.

CONCLUSIONS

Our systematic review provided comprehensive evidence for the impact of colour-coded labels and warnings in nudging consumers' purchasing behaviour towards more healthful products and the underlying psychological mechanism of behavioural change. Each type of label had different attributes, which should be taken into consideration when making front-of-package nutrition labelling (FOPL) policies according to local contexts. Our study supported mandatory front-of-pack labelling policies in directing consumers' choice and encouraging the food industry to reformulate their products.

PROTOCOL REGISTRY

PROSPERO (CRD42020161877).

Nudging healthcare professionals in clinical settings: a scoping review of the literature

BACKGROUND

Healthcare organisations are in constant need of improvement and change. Nudging has been proposed as a strategy to affect people's choices and has been used to affect patients' behaviour in healthcare settings. However, little is known about how nudging is being interpreted and applied to change the behaviour of healthcare professionals (HCPs). The objective of this review is to identify interventions using nudge theory to affect the behaviour of HCPs in clinical settings.

METHODS

A scoping review. We searched PubMed and PsycINFO for articles published from 2010 to September 2019, including terms related to "nudging" in the title or abstract. Two reviewers screened articles for inclusion based on whether the articles described an intervention to change the behaviour of HCPs. Two reviewers extracted key information and categorized included articles. Descriptive analyses were performed on the data.

RESULTS

Search results yielded 997 unique articles, of which 25 articles satisfied the inclusion criteria. Five additional articles were selected from the reference lists of the included articles. We identified 11 nudging strategies: accountable justification, goal setting, suggested alternatives, feedback, information transparency, peer comparison, active choice, alerts and reminders, environmental cueing/priming, defaults/pre-orders, and education. These strategies were employed to affect the following 4 target behaviours: vaccination of staff, hand hygiene, clinical procedures, prescriptions and orders. To compare approaches across so many areas, we introduced two independent dimensions to describe nudging strategies: synchronous/asynchronous, and active/passive.

CONCLUSION

There are relatively few studies published referring to nudge theory aimed at changing HCP behaviour in clinical settings. These studies reflect a diverse set of objectives and implement nudging strategies in a variety of ways. We suggest distinguishing active from passive nudging strategies. Passive nudging strategies may achieve the desired outcome but go unnoticed by the clinician thereby not really changing a behaviour and raising ethical concerns. Our review indicates that there are successful active strategies that engage with clinicians in a more deliberate way. However, more research is needed on how different nudging strategies impact HCP behaviour in the short and long term to improve clinical decision making.

The role of nitrogen in achieving sustainable food systems for healthy diets

The 'food system' urgently needs a sustainable transformation. Two major challenges have to be solved: the food system has to provide food security with healthy, accessible, affordable, safe and diverse food for all, and it has to do so within the safe operating space of the planetary boundaries, where the pollution from reactive nitrogen turned out to be the largest bottleneck. Here we argue that thinking strategically about how to balance nitrogen flows throughout the food system will make current food systems more resilient and robust. Looking from a material and a governance perspective on the food system, we highlight major nitrogen losses and policy blind spots originating from a compartmentalization of food system spheres. We conclude that a participatory and integrated approach to manage nitrogen flows throughout the food system is necessary to stay within regional and global nitrogen boundaries, and will additionally provide synergies with a sustainable and healthy diet for all.

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

The Multifaceted Dimensions of Food Choice and Nutrition

The Special Issue "Food Choice and Nutrition" deals with the relationship between the food choices of different population groups or consumer segments and its impact on the nutritional status, improvement of dietary quality, food and nutrition-related behaviour, food preferences, taste education, sensory characteristics of foods and their role in consumer choice, etc [...].