Leveraging delay discounting for health: Can time delays influence food choice?

Evaluating source credibility effects in health labelling using vending machines in a hospital setting

OBJECTIVES

Providing advice to consumers in the form of labelling may mitigate the increased availability and low cost of foods that contribute to the obesity problem. Our objective was to test whether making the source of the health advice on the label more credible makes labelling more effective.

METHODS AND MEASURES

Vending machines in different locations were stocked with healthy and unhealthy products in a hospital. Healthy products were randomly assigned to one of three conditions (i) a control condition in which no labelling was present (ii) a low source credibility label, "Lighter choices", and (iii) a high source credibility label that included the UK National Health Service (NHS) logo and name, "NHS lighter choices". Unhealthy products received no labelling. The outcome measure was sales volume.

RESULTS

There were no main effects of labelling. However, there were significant interactions between labelling, vending machine location and payment type. For one location and payment type, sales of products increased in the high credibility label condition compared to control, particularly for unhealthy products, contrary to expectations.

CONCLUSIONS

Our findings suggest that high source credibility health labels (NHS endorsement) on food either have little effect, or worse, can "backfire" and lead to effects opposite to those intended. The primary limitations are the limited range of source credibility labels and the scale of the study.

The association of impulsivity with effects of the ChooseWell 365 workplace nudge intervention on diet and weight

Impulsivity is associated with unhealthy food choices. Nudge interventions in the food environment may be particularly helpful for individuals with high impulsivity. To examine if trait, choice, and action impulsivity were associated with the effectiveness of a workplace-based nudge intervention to improve diet and weight. This was a planned secondary analysis of 487 participants of ChooseWell 365, a randomized controlled trial that tested a 12-month nudge intervention to improve cafeteria purchases among hospital employees. Trait impulsivity was measured with the Barratt Impulsiveness Scale. Choice and action impulsivity were assessed with delay discounting and response inhibition tasks, respectively. Tertiles were generated for each measure. Multivariable regression models examined the association of impulsivity with cafeteria purchases [Healthy Purchasing Score (HPS)] over 12 months, dietary intake [Healthy Eating Index-2015 (HEI) score], and body mass index (BMI) measured at 12 months. Interaction terms tested differences in intervention effect by level of impulsivity. Participants with higher trait (p = .02) and choice (p < .001) impulsivity had lower baseline HPS than those with lower impulsivity. Employees of all impulsivity levels increased healthy eating, but higher trait impulsivity was associated with smaller increase in HPS over 12 months (p = .03). In the highest action impulsivity tertile, 12-month BMI increased less for intervention vs. control participants (0.3 vs. 0.5 kg/m2; p-interaction = .04). There were no interaction effects for trait or choice impulsivity. A workplace nudge intervention improved food choices among employees of all impulsivity levels and attenuated weight gain in those with higher action impulsivity.

Information, ingestion, and impulsivity: The impact of technology-enabled healthy food labels on online grocery shopping in impulsive and non-impulsive consumers

Introduction

Unhealthy food consumption is a problem for society, companies, and consumers. This study aims to contribute to knowledge regarding such issues by investigating how technology-enabled healthy food labels can impact food choice in an online grocery store context. We conceptualized unhealthy and healthy food choice as a matter of impulsivity problems. Three technology-enabled healthy food labels were derived based on variables that might impact self-control, and their influence on food choice was investigated.

Methods

The empirical study consisted of three parts. In the first part, participants’ impulsivity was measured using an adjusting delay task. Part two investigated the effects of self-monitoring, pre-commitment, and social comparison-based technology-enabled healthy food labels on food choice in a hypothetical online grocery shopping setting using a choice-based conjoint experiment. Lastly, in the third part, three where demographical questions were asked.

Results

The results (n = 405) show that self-monitoring, pre-commitment, and social comparison-based technology-enabled healthy food labels had the most to least impact on food choice in that order. Furthermore, the results indicate that self-monitoring and pre-commitment labels had more impact on the choice for impulsive compared to non-impulsive participants. Similarly, the results indicate that social comparison had more impact on choice for non-impulsive participants. These findings suggest that self-monitoring of previous healthy food choices might be more effective than pre-commitment based on discounts for healthy food products. However, these differences were minor.

Discussion

This finding has managerial implications as grocery stores might increase their revenue by introducing self-monitoring labels in an online grocery shopping setting. Future research should investigate these technology-enabled healthy food labels in natural food purchase settings.

Attitudes, Habits, and Behavior Change

Efforts to guide peoples' behavior toward environmental sustainability, good health, or new products have emphasized informational and attitude change strategies. There is evidence that changing attitudes leads to changes in behavior, yet this approach takes insufficient account of the nature and operation of habits, which form boundary conditions for attitude-directed interventions. Integration of research on attitudes and habits might enable investigators to identify when and how behavior change strategies will be most effective. How might attitudinally driven behavior change be consolidated into lasting habits? How do habits protect the individual against the vicissitudes of attitudes and temptations and promote goal achievement? How might attitudinal approaches aiming to change habits be improved by capitalizing on habit discontinuities and strategic planning? When and how might changing or creating habit architecture shape habits directly? A systematic approach to these questions might help move behavior change efforts from attitude change strategies to habit change strategies. Expected final online publication date for the Annual Review of Psychology, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Calorie deprivation impairs the self-control of eating, but not of other behaviors

OBJECTIVE

Sustained weight loss is difficult to achieve, and weight regain is common due to biological and psychological changes caused by calorie deprivation. These changes are thought to undermine weight loss efforts by making self-control more difficult. However, there is a lack of evidence showing a causal relationship between calorie deprivation and behavioral self-control.

DESIGN

In this longitudinal field experiment, we tested whether a ten-day period of calorie deprivation leads to the impairment of behavioral self-control. Participants were randomly assigned to either restrict their calorie intake or to continue eating normally for the study period.

MAIN OUTCOME MEASURES

Participants were given a box of food and non-food 'treats' (i.e., chocolates and lottery tickets) that they were asked to resist until the end of the study. On the last day, researchers recorded the number of treats that remained for each participant.

RESULTS

Nonparametric permutation tests revealed that calorie-deprived participants ate significantly more chocolates than control participants did (p = 0.036), but that participants did not differ in the number of lottery tickets 'scratched' by condition (p = 0.332).

CONCLUSION

This pattern of findings suggests that calorie deprivation impairs food-related self-control, but that this self-control deficit may not generalize beyond food-related tasks.

The health benefits and cost-effectiveness of complete healthy vending

Vending machines contribute to growing levels of obesity. They typically contain energy dense, high fat snacks and attempts at persuading consumers to switch to healthier snacks sold within the same machine have had limited success. This study explored the health benefits and cost effectiveness of the complete replacement of regular snacks with healthy items. Two vending machines were manipulated in a 6-month trial, with a healthy and regular range of products alternated between the two machines every fortnight. Healthy vending resulted in a 61% drop in calories sold relative to regular vending, significant with time and product range as random factors. There was no evidence of compensatory behaviour from nearby shop sales nor in multi-item purchases from vending machines. The impact on profit was less clear. Sales dropped by 30% during healthy vending but variability across product range meant that the change was not significant. Overall our results demonstrate that complete healthy vending can be introduced in hospitals without a catastrophic loss in sales nor compensatory behaviours that offset the public health gains of consuming healthier products.

Taxation of unprocessed sugar or sugar-added foods for reducing their consumption and preventing obesity or other adverse health outcomes

BACKGROUND

Global prevalence of overweight and obesity are alarming. For tackling this public health problem, preventive public health and policy actions are urgently needed. Some countries implemented food taxes in the past and some were subsequently abolished. Some countries, such as Norway, Hungary, Denmark, Bermuda, Dominica, St. Vincent and the Grenadines, and the Navajo Nation (USA), specifically implemented taxes on unprocessed sugar and sugar-added foods. These taxes on unprocessed sugar and sugar-added foods are fiscal policy interventions, implemented to decrease their consumption and in turn reduce adverse health-related, economic and social effects associated with these food products.

OBJECTIVES

To assess the effects of taxation of unprocessed sugar or sugar-added foods in the general population on the consumption of unprocessed sugar or sugar-added foods, the prevalence and incidence of overweight and obesity, and the prevalence and incidence of other diet-related health outcomes.

SEARCH METHODS

We searched CENTRAL, Cochrane Database of Systematic Reviews, MEDLINE, Embase and 15 other databases and trials registers on 12 September 2019. We handsearched the reference list of all records of included studies, searched websites of international organisations and institutions, and contacted review advisory group members to identify planned, ongoing or unpublished studies.

SELECTION CRITERIA

We included studies with the following populations: children (0 to 17 years) and adults (18 years or older) from any country and setting. Exclusion applied to studies with specific subgroups, such as people with any disease who were overweight or obese as a side-effect of the disease. The review included studies with taxes on or artificial increases of selling prices for unprocessed sugar or food products that contain added sugar (e.g. sweets, ice cream, confectionery, and bakery products), or both, as intervention, regardless of the taxation level or price increase. In line with Cochrane Effective Practice and Organisation of Care (EPOC) criteria, we included randomised controlled trials (RCTs), cluster-randomised controlled trials (cRCTs), non-randomised controlled trials (nRCTs), controlled before-after (CBA) studies, and interrupted time series (ITS) studies. We included controlled studies with more than one intervention or control site and ITS studies with a clearly defined intervention time and at least three data points before and three after the intervention. Our primary outcomes were consumption of unprocessed sugar or sugar-added foods, energy intake, overweight, and obesity. Our secondary outcomes were substitution and diet, expenditure, demand, and other health outcomes.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all eligible records for inclusion, assessed the risk of bias, and performed data extraction.Two review authors independently assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We retrieved a total of 24,454 records. After deduplicating records, 18,767 records remained for title and abstract screening. Of 11 potentially relevant studies, we included one ITS study with 40,210 household-level observations from the Hungarian Household Budget and Living Conditions Survey. The baseline ranged from January 2008 to August 2011, the intervention was implemented on September 2011, and follow-up was until December 2012 (16 months). The intervention was a tax - the so-called 'Hungarian public health product tax' - on sugar-added foods, including selected foods exceeding a specific sugar threshold value. The intervention includes co-interventions: the taxation of sugar-sweetened beverages (SSBs) and of foods high in salt or caffeine. The study provides evidence on the effect of taxing foods exceeding a specific sugar threshold value on the consumption of sugar-added foods. After implementation of the Hungarian public health product tax, the mean consumption of taxed sugar-added foods (measured in units of kg) decreased by 4.0% (standardised mean difference (SMD) -0.040, 95% confidence interval (CI) -0.07 to -0.01; very low-certainty evidence). The study was at low risk of bias in terms of performance bias, detection bias and reporting bias, with the shape of effect pre-specified and the intervention unlikely to have any effect on data collection. The study was at unclear risk of attrition bias and at high risk in terms of other bias and the independence of the intervention. We rated the certainty of the evidence as very low for the primary and secondary outcomes. The Hungarian public health product tax included a tax on sugar-added foods but did not include a tax on unprocessed sugar. We did not find eligible studies reporting on the taxation of unprocessed sugar. No studies reported on the primary outcomes of consumption of unprocessed sugar, energy intake, overweight, and obesity. No studies reported on the secondary outcomes of substitution and diet, demand, and other health outcomes. No studies reported on differential effects across population subgroups. We could not perform meta-analyses or pool study results.

AUTHORS' CONCLUSIONS

There was very limited evidence and the certainty of the evidence was very low. Despite the reported reduction in consumption of taxed sugar-added foods, we are uncertain whether taxing unprocessed sugar or sugar-added foods has an effect on reducing their consumption and preventing obesity or other adverse health outcomes. Further robustly conducted studies are required to draw concrete conclusions on the effectiveness of taxing unprocessed sugar or sugar-added foods for reducing their consumption and preventing obesity or other adverse health outcomes.

Experience Matters: The Effects of Hypothetical versus Experiential Delays and Magnitudes on Impulsive Choice in Delay Discounting Tasks

Impulsive choice in humans is typically measured using hypothetical delays and rewards. In two experiments, we determined how experiencing the delay and/or the reward affected impulsive choice behavior. Participants chose between two amounts of real or hypothetical candy (M&Ms) after a real or hypothetical delay (5-30 s), where choosing the shorter delay was the impulsive choice. Experiment 1 compared choice behavior on a real-delay, real-reward (RD/RR) task where participants received M&Ms after experiencing the delays versus a real-delay, hypothetical-reward (RD/HR) task where participants accumulated hypothetical M&Ms after experiencing the delays. Experiment 2 compared the RD/HR task and a hypothetical-delay, hypothetical-reward (HD/HR) task where participants accumulated hypothetical M&Ms after hypothetical delays. The results indicated that choices did not differ between real and hypothetical M&Ms (Experiment 1), and participants were less sensitive to delay and more larger-later (LL)-preferring with hypothetical delays compared to real delays (Experiment 2). Experiencing delays to reward may be important for modeling real-world impulsive choices where delays are typically experienced. These novel experiential impulsive choice tasks may improve translational methods for comparison with animal models and may be improved procedures for predicting real-life choice behavior in humans.

Healthy Eating: Approaching the Selection, Preparation, and Consumption of Healthy Food as Choice Behavior

Healthy eating has important well-being and financial implications for our society. As such, it is critical that the field of behavior science and behavior analysis conduct more research in this area so that effective interventions may be developed. One barrier to addressing healthy eating may be conceptual. Far from being a single response, eating is comprised of a series of choice responses. These selection, preparation and consumption responses form a temporally delayed behavioral chain. When designing interventions to address healthy eating, therefore, one must not only consider the specific target response, but alternative response options, and the effect of changing one response on other choices in the chain. The purpose of this article is to refine the analysis of healthy eating behavior, provide examples of research conducted in this area, and discuss how these interventions may influence this chain of responses. It is hoped that by doing so, additional research will be conducted and disseminated so that individuals, organizations, and policy makers can implement more effective interventions for healthy eating.