One man's tall is another man's small: how the framing of portion size influences food choice

High BMI Predicts Attention to Less Healthy Product Sets: Can a Prompt Lead to Consideration of Healthier Sets of Products?

While the food environment has been implicated in diet-related health disparities, individuals’ ability to shape the food environment by limiting attention to a subset of products has not been studied. We examine the relationship between BMI category and consideration set—the products the individual considers before making a final choice—in an online hypothetical shopping experiment. Specifically, we focus on the healthiness of the consideration set the individual selected. Secondly, we examined the interaction of a health prompt (versus a no-prompt control) with BMI category on the healthiness of the consideration set. We used linear probability models to document the relationship between weight status and consideration set, between prompt and consideration set, and the effect of the interaction between prompt and weight status on consideration set. We found that (1) obese individuals are 10% less likely to shop from a consideration set that includes the healthy options, (2) viewing the prompt increased the probability of choosing a healthy consideration set by 9%, and (3) exposure to the prompt affected individuals in different BMI categories equally. While obese individuals are more likely to ignore healthier product options, a health-focused prompt increases consideration of healthy options across all BMI categories.

The intuitive use of contextual information in decisions made with verbal and numerical quantifiers

Verbal and numerical formats (e.g., verbal: “low fat,” or numerical: “20% fat”) are used interchangeably to communicate nutritional information. However, prior research implies that verbal quantifiers are processed more intuitively than numerical ones. We tested this hypothesis in two pre-registered experiments measuring four indicators of processing style: (a) response time, (b) decision performance, (c) reliance on irrelevant contextual information, which we inferred from participants’ decision patterns, and (d) the level of interference from a concurrent memory task. Participants imagined they had consumed a given amount of a nutrient (represented in a pie chart) and decided whether a new quantity (either verbal or numerical) could be eaten within their guideline daily amount (GDA). The experiments used a mixed design varying format (verbal or numerical), concurrent memory load (no load, easy, and hard load in Experiment 1; no load and hard load in Experiment 2), nutrient (fat and minerals), quantity (low, medium, and high in Experiment 1; low and high in Experiment 2), and the assigned correct response for a trial (within and exceeding limits). Participants were faster and made fewer correct decisions with verbal quantifiers, and they relied more on contextual information (i.e., the identity of the nutrient involved). However, memory load did not impair decisions with verbal or numerical quantifiers. Altogether, these results suggest that verbal quantifiers are processed intuitively, slightly more so than numerical quantifiers, but that numerical quantifiers do not require much analytical processing to reach simple decisions.

Comparing and contrasting responses to tobacco control and obesity policies: a qualitative study

OBJECTIVE

To explore people's perceptions of, and responses to, obesity and tobacco policies with a particular focus on motivation; and to compare and contrast responses to explore the potential for translating learning across domains.

DESIGN

A theoretically informed comparative qualitative study involving semi-structured interviews with two groups of participants (smokers and ex-smokers; those who have previously or are currently attempting to lose weight). Data were analysed inductively using thematic analysis and interpreted through the lens of Self-Determination Theory.

SETTING

Community-based.

PARTICIPANTS

Interviews were conducted with five smokers and four ex-smokers around tobacco policy, and seventeen people acting to control their weight around obesity policy.

RESULTS

Three primary themes were identified. (i) Participants believed social norms to be crucial to supporting health behaviour change and responses to policy; not smoking was perceived as socially normal, whereas being physically active and eating healthily were perceived to go against social norms. (ii) Policies influencing the physical environment were perceived to support stopping smoking (e.g. smoke-free laws, advertising bans), but to undermine attempts to lose or control weight (e.g. high visibility, availability and low cost of energy-dense foods). (iii) While policies for both domains were considered necessary and legitimate, both groups found policy interventions neither motivating nor undermining of their sense of autonomy.

CONCLUSIONS

The results suggest those trying to lose weight respond similarly to obesity-related policy as smokers do to tobacco policy. Environmental interventions are perceived to be more helpful than appealing to people's motivation to change for their own sake.

Use and effectiveness of behavioural economics in interventions for lifestyle risk factors of non-communicable diseases: a systematic review with policy implications

AIM

There is limited evidence on what behavioural economics strategies are effective and can be used to inform non-communicable diseases (NCDs) public health policies designed to reduce overeating, excessive drinking, smoking, and physical inactivity. The aim of the review is to examine the evidence on the use and effectiveness of behavioural economics insights on reducing NCDs lifestyle risk factors.

METHODS

Medline, Embase, PsycINFO, and EconLit were searched for studies published between January 2002 and July 2016 and reporting empirical, non-pharmacological, interventional research focusing on reducing at least one NCDs lifestyle risk factor by employing a behavioural economics perspective.

RESULTS

We included 117 studies in the review; 67 studies had a low risk of bias and were classified as strong or very strong, 37 were moderate, and 13 were weak. We grouped studies by NCDs risk factors and conducted a narrative synthesis. The most frequent behavioural economics precepts used were incentives, framing, and choice architecture. We found inconclusive evidence regarding the success of behavioural economics strategies to reduce alcohol consumption, but we identified several strategies with policy-level implications which could be used to reduce smoking, improve nutrition, and increase physical activity.

CONCLUSION

Most studies targeting tobacco consumption, physical activity levels, and eating behaviours from a behavioural economics perspective had promising results with potential impact on NCDs health policies. We recommend future studies to be implemented in real-life settings and on large samples from diverse populations.

Integrating Behavioral Economics into Nutrition Education Research and Practice

Nutrition education has a long history of being informed by economic thinking, with the earliest nutrition education guides incorporating household food budgeting into nutrition advice. Behavioral economics research goes beyond that traditional role to provide new insights into how consumers make choices. These insights have numerous potential applications for nutrition interventions to promote healthy food choices consistent with the US Dietary Guidelines for Americans. Research to test the value of such applications can contribute to the development of evidence-based nutrition education practice called for in federal nutrition education programs.

Appetite self-regulation: Environmental and policy influences on eating behaviors

OBJECTIVE

Appetite regulation is influenced by the environment, and the environment is shaped by food-related policies. This review summarizes the environment and policy research portion of an NIH Workshop (Bethesda, MD, 2015) titled "Self-Regulation of Appetite-It's Complicated."

METHODS

In this paper, we begin by making the case for why policy is an important tool in efforts to improve nutrition, and we introduce an ecological framework that illustrates the multiple layers that influence what people eat. We describe the state of the science on how policies influence behavior in several key areas: the federal food programs, schools, child care, food and beverage pricing, marketing to youth, behavioral economics, and changing defaults. Next, we propose novel approaches for multidisciplinary prevention and intervention strategies to promote breastfeeding, and examine interactions between psychology and the environment.

RESULTS

Policy and environmental change are the most distal influences on individual-level appetite regulation, yet these strategies can reach many people at once by changing the environment in which food choices are made. We note the need for more research to understand compensatory behavior, reactance, and how to effectively change social norms.

CONCLUSIONS

To move forward, we need a more sophisticated understanding of how individual psychological and biological factors interact with the environment and policy influences.

Portion Size: Latest Developments and Interventions

PURPOSE OF REVIEW

The aim of this review is to provide an overview of (1) underlying mechanisms of the effect of portion size on energy intake, (2) external factors explaining the portion size effect and (3) interventions and measurements aimed at food portion size.

RECENT FINDINGS

Previous studies have shown that portion sizes have increased in recent decades. Many experimental studies have been conducted to unravel the mechanisms underlying the portion-size effect on food intake (e.g. the appropriateness mechanism, the 'unit bias' mechanism, the 'previous experience/expectation' mechanism, the 'visual cue' mechanism and the 'bite size' mechanism). In addition, external factors have been found to drive food portion selection and consumption (e.g. value for money, mindless eating, levels of awareness, estimation bias. Research on several interventions (ranging from 'providing information' to 'eliminating choice') have been conducted, but remain scarce, especially intervention studies in which portion size is a key focus in weight loss. Moreover, only three new instruments with respect to portion control behavior have been developed. There is considerable evidence for the portion-size effect on energy intake. However, the work on interventions targeting portion size and measurements for portion control behavior are limited. Moreover, from the literature it is not yet clear what type of interventions work best, for whom and in what context.

Environmental Strategies to Promote Food Intake in Older Adults: A Narrative Review

Aging is often accompanied by lower intakes of food energy and consequent negative effects on health. To some extent this is due to declines in physiological ability, including the sensory responsiveness to regulate food intake. Fortunately, environmental factors may still influence food intake in older adults. Factors such as social facilitation, modeling, and nutrition knowledge and skills have been shown to stimulate their food intake. While environmental factors such as the eating location, portion size, food presentation, and labeling are known to influence eating behavior, their effectiveness in stimulating food intake in older persons is not well delineated. It is suggested that improving the environmental stimuli that promote food intake is a viable strategy to overcome age-related declines in nutrient intakes. This strategy is so promising that further research is warranted.

Survival or Mortality: Does Risk Attribute Framing Influence Decision-Making Behavior in a Discrete Choice Experiment?

OBJECTIVE

To test how attribute framing in a discrete choice experiment (DCE) affects respondents' decision-making behavior and their preferences.

METHODS

Two versions of a DCE questionnaire containing nine choice tasks were distributed among a representative sample of the Dutch population aged 55 to 65 years. The DCE consisted of four attributes related to the decision regarding participation in genetic screening for colorectal cancer (CRC). The risk attribute included was framed positively as the probability of surviving CRC and negatively as the probability of dying from CRC. Panel mixed-logit models were used to estimate the relative importance of the attributes. The data of the positively and negatively framed DCE were compared on the basis of direct attribute ranking, dominant decision-making behavior, preferences, and importance scores.

RESULTS

The majority (56%) of the respondents ranked survival as the most important attribute in the positively framed DCE, whereas only a minority (8%) of the respondents ranked mortality as the most important attribute in the negatively framed DCE. Respondents made dominant choices based on survival significantly more often than based on mortality. The framing of the risk attribute significantly influenced all attribute-level estimates and resulted in different preference structures among respondents in the positively and negatively framed data set.

CONCLUSIONS

Risk framing affects how respondents value the presented risk. Positive risk framing led to increased dominant decision-making behavior, whereas negative risk framing led to risk-seeking behavior. Attribute framing should have a prominent part in the expert and focus group interviews, and different types of framing should be used in the pilot version of DCEs as well as in actual DCEs to estimate the magnitude of the effect of choosing different types of framing.

Using Healthy Defaults in Walt Disney World Restaurants to Improve Nutritional Choices

A retrospective study of kids' meals purchased at Walt Disney World was conducted to determine acceptance rates for healthy sides and beverages. Purchase data from all 145 Walt Disney World restaurants were analyzed using a log-linear model and a Poisson regression. Across all restaurants, 47.9% and 66.3% of guests accepted healthy default sides and beverages, respectively. Acceptance rates of sides and beverages were higher at quick-service restaurants (49.4% and 67.8%, respectively) compared to table-service restaurants (40.3% and 45.6%, respectively). The healthy defaults reduced calories (21.4%), fat (43.9%), and sodium (43.4%) for kids' meal sides and beverages. This study contributes by examining the use of kids' meal healthy defaults in quick-service and table-service restaurant formats at the world's largest theme park, a previously unstudied setting, and by providing the largest ever healthy default data set. The results suggest that healthy defaults can shift food and beverage selection patterns toward healthier options.

Portion, package or tableware size for changing selection and consumption of food, alcohol and tobacco

BACKGROUND

Overeating and harmful alcohol and tobacco use have been linked to the aetiology of various non-communicable diseases, which are among the leading global causes of morbidity and premature mortality. As people are repeatedly exposed to varying sizes and shapes of food, alcohol and tobacco products in environments such as shops, restaurants, bars and homes, this has stimulated public health policy interest in product size and shape as potential targets for intervention.

OBJECTIVES

1) To assess the effects of interventions involving exposure to different sizes or sets of physical dimensions of a portion, package, individual unit or item of tableware on unregulated selection or consumption of food, alcohol or tobacco products in adults and children.2) To assess the extent to which these effects may be modified by study, intervention and participant characteristics.

SEARCH METHODS

We searched CENTRAL, MEDLINE, EMBASE, PsycINFO, eight other published or grey literature databases, trial registries and key websites up to November 2012, followed by citation searches and contacts with study authors. This original search identified eligible studies published up to July 2013, which are fully incorporated into the review. We conducted an updated search up to 30 January 2015 but further eligible studies are not yet fully incorporated due to their minimal potential to change the conclusions.

SELECTION CRITERIA

Randomised controlled trials with between-subjects (parallel-group) or within-subjects (cross-over) designs, conducted in laboratory or field settings, in adults or children. Eligible studies compared at least two groups of participants, each exposed to a different size or shape of a portion of a food (including non-alcoholic beverages), alcohol or tobacco product, its package or individual unit size, or of an item of tableware used to consume it, and included a measure of unregulated selection or consumption of food, alcohol or tobacco.

DATA COLLECTION AND ANALYSIS

We applied standard Cochrane methods to select eligible studies for inclusion and to collect data and assess risk of bias. We calculated study-level effect sizes as standardised mean differences (SMDs) between comparison groups, measured as quantities selected or consumed. We combined these results using random-effects meta-analysis models to estimate summary effect sizes (SMDs with 95% confidence intervals (CIs)) for each outcome for size and shape comparisons. We rated the overall quality of evidence using the GRADE system. Finally, we used meta-regression analysis to investigate statistical associations between summary effect sizes and variant study, intervention or participant characteristics.

MAIN RESULTS

The current version of this review includes 72 studies, published between 1978 and July 2013, assessed as being at overall unclear or high risk of bias with respect to selection and consumption outcomes. Ninety-six per cent of included studies (69/72) manipulated food products and 4% (3/72) manipulated cigarettes. No included studies manipulated alcohol products. Forty-nine per cent (35/72) manipulated portion size, 14% (10/72) package size and 21% (15/72) tableware size or shape. More studies investigated effects among adults (76% (55/72)) than children and all studies were conducted in high-income countries - predominantly in the USA (81% (58/72)). Sources of funding were reported for the majority of studies, with no evidence of funding by agencies with possible commercial interests in their results.A meta-analysis of 86 independent comparisons from 58 studies (6603 participants) found a small to moderate effect of portion, package, individual unit or tableware size on consumption of food (SMD 0.38, 95% CI 0.29 to 0.46), providing moderate quality evidence that exposure to larger sizes increased quantities of food consumed among children (SMD 0.21, 95% CI 0.10 to 0.31) and adults (SMD 0.46, 95% CI 0.40 to 0.52). The size of this effect suggests that, if sustained reductions in exposure to larger-sized food portions, packages and tableware could be achieved across the whole diet, this could reduce average daily energy consumed from food by between 144 and 228 kcal (8.5% to 13.5% from a baseline of 1689 kcal) among UK children and adults. A meta-analysis of six independent comparisons from three studies (108 participants) found low quality evidence for no difference in the effect of cigarette length on consumption (SMD 0.25, 95% CI -0.14 to 0.65).One included study (50 participants) estimated a large effect on consumption of exposure to differently shaped tableware (SMD 1.17, 95% CI 0.57 to 1.78), rated as very low quality evidence that exposure to shorter, wider bottles (versus taller, narrower bottles) increased quantities of water consumed by young adult participants.A meta-analysis of 13 independent comparisons from 10 studies (1164 participants) found a small to moderate effect of portion or tableware size on selection of food (SMD 0.42, 95% CI 0.24 to 0.59), rated as moderate quality evidence that exposure to larger sizes increased the quantities of food people selected for subsequent consumption. This effect was present among adults (SMD 0.55, 95% CI 0.35 to 0.75) but not children (SMD 0.14, 95% CI -0.06 to 0.34).In addition, a meta-analysis of three independent comparisons from three studies (232 participants) found a very large effect of exposure to differently shaped tableware on selection of non-alcoholic beverages (SMD 1.47, 95% CI 0.52 to 2.43), rated as low quality evidence that exposure to shorter, wider (versus taller, narrower) glasses or bottles increased the quantities selected for subsequent consumption among adults (SMD 2.31, 95% CI 1.79 to 2.83) and children (SMD 1.03, 95% CI 0.41 to 1.65).

AUTHORS' CONCLUSIONS

This review found that people consistently consume more food and drink when offered larger-sized portions, packages or tableware than when offered smaller-sized versions. This suggests that policies and practices that successfully reduce the size, availability and appeal of larger-sized portions, packages, individual units and tableware can contribute to meaningful reductions in the quantities of food (including non-alcoholic beverages) people select and consume in the immediate and short term. However, it is uncertain whether reducing portions at the smaller end of the size range can be as effective in reducing food consumption as reductions at the larger end of the range. We are unable to highlight clear implications for tobacco or alcohol policy due to identified gaps in the current evidence base.

Opportunities and barriers for smaller portions in food service: lessons from marketing and behavioral economics

This paper uses the frameworks and evidence from marketing and behavioral economics to highlight the opportunities and barriers for portion control in food service environments. Applying Kahneman's 'thinking fast and slow' concepts, it describes 10 strategies that can be effective in 'tricking' the consumer's fast cognitive system to make better decisions and in triggering the slow cognitive system to help prevent the fast system from making bad decisions. These strategies include shrinking defaults, elongating packages, increasing the visibility of small portions, offering more mixed virtue options, adding more small sizes, offering 'right-sized' standard portions, using meaningful size labels, adopting linear pricing, using temporal landmarks to push smaller portions and facilitating pre-commitment. For each of these strategies, I discuss the specific cost and revenue barriers that a food service operator would face if the strategy were adopted.

Improving the design of nutrition labels to promote healthier food choices and reasonable portion sizes

Accurate and easy-to-understand nutrition labeling is a worthy public health goal that should be considered an important strategy among many to address obesity and poor diet. Updating the Nutrition Facts Panel on packaged foods, developing a uniform front-of-package labeling system and providing consumers with nutrition information on restaurant menus offer important opportunities to educate people about food's nutritional content, increase awareness of reasonable portion sizes and motivate consumers to make healthier choices. The aims of this paper were to identify and discuss: (1) current concerns with nutrition label communication strategies; (2) opportunities to improve the communication of nutrition information via food labels, with a specific focus on serving size information; and (3) important future areas of research on nutrition labeling as a tool to improve diet. We suggest that research on nutrition labeling should focus on ways to improve food labels' ability to capture consumer attention, reduce label complexity and convey numeric nutrition information in simpler and more meaningful ways, such as through interpretive food labels, the addition of simple text, reduced use of percentages and easy-to-understand presentation of serving size information.

Weighing the Evidence of Common Beliefs in Obesity Research

Obesity is a topic on which many views are strongly held in the absence of scientific evidence to support those views, and some views are strongly held despite evidence to contradict those views. We refer to the former as "presumptions" and the latter as "myths." Here, we present nine myths and 10 presumptions surrounding the effects of rapid weight loss; setting realistic goals in weight loss therapy; stage of change or readiness to lose weight; physical education classes; breastfeeding; daily self-weighing; genetic contribution to obesity; the "Freshman 15"; food deserts; regularly eating (versus skipping) breakfast; eating close to bedtime; eating more fruits and vegetables; weight cycling (i.e., yo-yo dieting); snacking; built environment; reducing screen time in childhood obesity; portion size; participation in family mealtime; and drinking water as a means of weight loss. For each of these, we describe the belief and present evidence that the belief is widely held or stated, reasons to support the conjecture that the belief might be true, evidence to directly support or refute the belief, and findings from randomized controlled trials, if available. We conclude with a discussion of the implications of these determinations, conjecture on why so many myths and presumptions exist, and suggestions for limiting the spread of these and other unsubstantiated beliefs about the obesity domain.

Restaurant owners' perspectives on a voluntary program to recognize restaurants for offering reduced-size portions, Los Angeles County, 2012

Introduction

Reducing the portion size of food and beverages served at restaurants has emerged as a strategy for addressing the obesity epidemic; however, barriers and facilitators to achieving this goal are not well characterized.

Methods

In fall 2012, the Los Angeles County Department of Public Health conducted semistructured interviews with restaurant owners to better understand contextual factors that may impede or facilitate participation in a voluntary program to recognize restaurants for offering reduced-size portions.

Results

Interviews were completed with 18 restaurant owners (representing nearly 350 restaurants). Analyses of qualitative data revealed 6 themes related to portion size: 1) perceived customer demand is central to menu planning; 2) multiple portion sizes are already being offered for at least some food items; 3) numerous logistical barriers exist for offering reduced-size portions; 4) restaurant owners have concerns about potential revenue losses from offering reduced-size portions; 5) healthful eating is the responsibility of the customer; and 6) a few owners want to be socially responsible industry leaders.

Conclusion

A program to recognize restaurants for offering reduced-size portions may be a feasible approach in Los Angeles County. These findings may have applications for jurisdictions interested in engaging restaurants as partners in reducing the obesity epidemic.