Trends (2014-2018) in the healthiness of packaged food purchases of Australian consumers before and after the introduction of voluntary Health Star Rating nutrition labels.

OBJECTIVE: To evaluate the trends in the healthiness of packaged food purchases of Australian consumers before and after the introduction of the Health Star Rating (HSR) nutrition labels. DESIGN: Panel data analysis and difference-in-differences analysis. SETTING: The Australian Government endorsed HSR nutrition labels for voluntary implementation on packaged foods in June 2014. We analyse the packaged food purchases of households across all major supermarkets before (January 2014 to June 2014) and after (June 2014-Dec 2018) the introduction of HSR. PARTICIPANTS: 6284 members of a panel of households across Australia reporting their grocery purchases to a market research company (Nielsen Homescan panel). RESULTS: The healthiness of household food purchases exhibited a U-shaped trend - decreasing from 2014 to 2017, and then increasing from 2018, corresponding to the time when a higher proportion of products were HSR-labelled. Households that purchased a higher proportion of HSR-labelled products had healthier household purchases overall. Further, the healthiness of households' category-specific food purchases was positively associated with the proportion of HSR-labelled products in categories where HSR was adopted, relative to control categories where HSR was not adopted. CONCLUSIONS: In Australia, once a substantial number of packaged food products adopted the voluntary HSR summary indicator, we observed an increasing trend in the healthiness of household food purchases. Widespread adoption of a nutrition summary indicator, such as HSR, on packaged food is likely to be beneficial for population health.

Effects of environmental impact and nutrition labelling on food purchasing: An experimental online supermarket study.

Nutrition labels and ecolabels can support consumers to make healthier and more sustainable choices, and the former is now widespread. But there is no information on the impact of ecolabels in the presence of nutrition labels. The aims of this study were primarily to examine whether (1) ecolabels are effective at promoting sustainable purchasing behaviour if presented alongside nutrition labels; (2) and secondarily, whether nutrition labels are effective at promoting healthier purchasing if presented alongside ecolabels. Participants (N = 2730) visited an experimental online supermarket platform, and were randomised to see products with (1) environmental impact labels only; (2) nutrition (NutriScore) labels only; (3) both environmental and nutrition labels; (4) no labels. Linear regressions compared the mean environmental impact scores (EIS; primary outcome) and health scores of products in participants' shopping baskets across each condition. Compared to control (no labels) there were significant reductions in the EIS when environmental impact labels were presented: Alone (-1.3, 95%CI: -2.3 to -0.4) or With nutrition labels (-2.0, 95%CI: -2.9 to -1.0), with no evidence of differences in effectiveness between these two conditions. There was no evidence of an impact of nutrition labels on either the EIS or the healthiness of purchases, both when nutrition labels were shown alone and when ecolabels were also present. Environmental impact labels may be effective at encouraging more sustainable purchases alone or when used alongside nutrition labels. This adds to the evidence base on the feasibility and effectiveness of environmental impact labelling as an important measure to change dietary behaviour to improve planetary health.

Current use of nutrition facts tables and attitudes towards new red and green front-of-package labels among Israeli consumers.

Front-of-package labels (FOPL) are designed to simplify nutrition information and to help consumers make healthier food choices. The Israeli government has implemented new regulations requiring mandatory red warning FOPL for high levels of sodium, sugar, or saturated fats. A voluntary green positive FOPL for products fitting the national nutritional recommendations was concurrently encouraged. In order to characterise adult consumers' current use of Nutrition Facts Tables (NFT) and their attitudes towards the new FOPL, a nationally representative cross-sectional telephone survey was conducted. Most of the 1,042 survey respondents reported frequent NFT use (76.2%) and intentions to purchase fewer red-labelled (81.1%) and more green-labelled products (85.0%). Consumers with higher BMI and lower education expressed higher intentions to use the new FOPL, but not higher current use of NFT. This finding suggests that these high-risk groups, which the new labels are meant to target, may indeed benefit from the new policy.

Regulating Obesity in Australia: Current Frameworks, Reflections upon the Impact of COVID-19 and Future Reform.

This article considers the legal and policy regulatory frameworks in Australia relevant to two of the key areas identified as central to managing and preventing obesity, namely, food labelling and junk food advertising. It does so against the backdrop of a global pandemic which resulted in a perfect storm: a global virus colliding with an obesity epidemic. The aetiology of the COVID-19 virus, and the isolation and shut down restrictions associated with combatting it, mean that introducing reforms in these key areas is, more than ever, a public health priority. This article provides important practical recommendations to modify legal and regulatory policy frameworks in the two key areas to address the obesity epidemic in Australia.

The role of colour and summary indicators in influencing front-of-pack food label effectiveness across seven countries.

OBJECTIVE: Many countries are considering the implementation of front-of-pack nutrition labels as a strategy to address high and increasing levels of overweight and obesity. A growing body of work demonstrates the superiority of labels that use colour and/or provide a summary indicator of product healthiness to enhance comprehension. However, previous studies have been confounded in determining the relative effectiveness of these two attributes by comparing labels that also differ in other ways. The present study tested labels that varied only on use of colour and/or reliance on a summary indicator across an international sample to provide unique insights into the relative importance of these attributes. DESIGN: Participants were randomised to see one of four variations of the Health Star Rating label that differed on the basis of use of colour and sole provision of a summary indicator. SETTING: Australia, Canada, China, India, New Zealand, the UK and the USA. PARTICIPANTS: Adults (n 7545) in seven countries were exposed to online choice tasks requiring them to select a preferred breakfast cereal and then nominate the healthiest cereal. RESULTS: Overall, the coloured versions, and particularly the one with just a summary indicator, outperformed the monochrome version that included nutrient-specific information. However, there were some differences by country, with results from Canada and China indicating superior outcomes for monochrome labels and those providing nutrient-specific information. CONCLUSIONS: The results highlight the importance of colour, but suggest that the introduction of front-of-pack nutrition labels should be preceded by country-specific formative testing to identify potential differences in outcomes.

Evaluating and communicating about the healthiness of foods: Predictors of parents' judgments and parent-child conversations.

Parents are typically in charge of purchasing the food that their children eat, but little is known about how parents decide if particular foods are healthy for their children and how their beliefs about nutrition influence their children's beliefs. In two studies, we investigated how parents of children ages 4 to 12 (N = 826) make decisions about the healthiness of foods, when presented with different representations of the same nutritional information. Providing parents with nutritional information did not influence their ratings of how healthy food items are, compared to when they are shown only pictures of the foods. Parents reported talking with their children about nutrition, believed they are the best source of information for children about nutrition, and believed their nutrition beliefs influence their child's beliefs. Our findings highlight the role of prior knowledge in food cognition and how beliefs about foods are transmitted from parents to children.

Commercially produced complementary foods in Bandung City, Indonesia, are often reported to be iron fortified but with less than recommended amounts or suboptimal forms of iron.

Commercially produced complementary foods (CPCF) that are iron fortified can help improve iron status of young children. We conducted a review of 217 CPCF sold in 42 stores in Bandung, Indonesia, in 2017. There were 95 (44%) infant cereals, 71 (33%) snacks or finger foods (biscuits or cookies, puffs, and noodles or crackers), 35 (16%) purees, and 16 (7%) other foods for which we obtained label information. Nearly 70% of CPCF reported iron content on their labels, but only 58% of products were reported to be fortified with iron according to ingredient lists. Among iron-fortified products, only one fifth indicated a specific type of iron used as the fortificant, but all of these were recommended by the World Health Organization for fortifying complementary foods. Infant cereal was more likely to contain added iron (81%) compared with snacks or finger food (58%) and purees (14%) and had higher iron content per median serving size (cereal = 3.8 mg, snacks or finger food = 1.3 mg, mixed meals = 2.7 mg, and purees = 0.9 mg). Infant cereal was most likely to meet the recommended daily intakes for iron (41% for infants 6-12 months of age and 66% for children 12-36 months) compared with snacks or finger food (infants = 14%, children = 22%), mixed meals (infants = 28%, children = 46%), or purees (infants = 9%, children = 15%). Regulations on fortification of complementary foods need to specify minimum levels and forms of iron and require reporting in relation to requirements by child age and serving size. Monitoring and enforcement of regulations will be essential to ensure compliance.

Nutrition labeling reduces valuations of food through multiple health and taste channels.

One popularized technique to promote healthy dietary choice involves posting calorie or other nutritional information at the time individuals make a consumption decision. While the evidence on the effectiveness of such interventions is mixed, relatively little work has focused on the underlying mechanisms of how such labels alter behavior. In the research reported here, we asked 87 hungry laboratory subjects to make bids over foods with or without nutrition labels present. We found that the presence of a nutrition label reduced bids by an average of 25 cents. Furthermore, we found this reduction was driven by differences in perceptions and the importance individuals placed on health features of the foods, but also by differences in the importance individuals placed on more visceral taste features. These results help explain the various methods in which nutritional information postings or other policy tools can nudge individuals to consume healthier options.

Self-reported use of nutrition labels to make food choices is associated with healthier dietary behaviours in adolescents.

OBJECTIVE: The study aimed to examine nutrition label use and dietary behaviours among ethnically diverse middle- and high-school students, in Texas, USA. DESIGN: The School Physical Activity and Nutrition (SPAN) survey is a cross-sectional statewide study using a self-administered questionnaire to assess nutrition and physical activity behaviours. Height and weight measurements were used to determine BMI. Multivariable logistic regression was used to determine associations between nutrition label use and dietary behaviours, with gender, grade, ethnicity, BMI, parent education, socio-economic status and nutrition knowledge as covariates. SETTING: Participants from 283 schools, weighted to represent Texas youth. SUBJECTS: SPAN 2009-2011 included 6716 8th and 11th graders (3465 girls and 3251 boys). The study population consisted of 39·83 % White/Other, 14·61 % African-American and 45·56 % Hispanic adolescents; with a mean age of 14·9 years, and 61·95 % at a healthy weight, 15·71 % having overweight and 22·34 % having obesity. RESULTS: Adolescents who did not use nutrition labels had 1·69 times greater odds of consuming ≥1 sugary beverages/d (P<0·05). Adolescents who used nutrition labels had 2·13 times greater odds of consuming ≥1 fruits and vegetables/d (P<0·05). Adolescents who used nutrition labels had significantly higher healthy eating scores than those who did not (P<0·001). For every 1-point increase in nutrition knowledge, adolescents had 1·22 greater odds of using nutrition labels. CONCLUSIONS: Nutrition label use is associated with healthier dietary behaviours in adolescents. Intervention strategies for youth should include efforts to teach adolescents to use labels to make healthy food choices.

Nutrition warnings as front-of-pack labels: influence of design features on healthfulness perception and attentional capture.

OBJECTIVE: Warnings are a new directive front-of-pack (FOP) nutrition labelling scheme that highlights products with high content of key nutrients. The design of warnings influences their ability to catch consumers' attention and to clearly communicate their intended meaning, which are key determinants of their effectiveness. The aim of the present work was to evaluate the influence of design features of warnings as a FOP nutrition labelling scheme on perceived healthfulness and attentional capture. DESIGN: Five studies with a total of 496 people were carried out. In the first study, the association of colour and perceived healthfulness was evaluated in an online survey in which participants had to rate their perceived healthfulness of eight colours. In the second study, the influence of colour, shape and textual information on perceived healthfulness was evaluated using choice-conjoint analysis. The third study focused on implicit associations between two design features (shape and colour) on perceived healthfulness. The fourth and fifth studies used visual search to evaluate the influence of colour, size and position of the warnings on attentional capture. RESULTS: Perceived healthfulness was significantly influenced by shape, colour and textual information. Colour was the variable with the largest contribution to perceived healthfulness. Colour, size and position of the warnings on the labels affected attentional capture. CONCLUSIONS: Results from the experiments provide recommendations for the design of warnings to identify products with unfavourable nutrient profile.

Unregulated serving sizes on the Canadian nutrition facts table - an invitation for manufacturer manipulations.

BACKGROUND: Serving sizes on the Nutrition Facts table (NFt) on Canadian packaged foods have traditionally been unregulated and non-standardized. The federal government recently passed legislation to regulate the serving sizes listed on the NFt. The objective of this study was to compare the serving sizes on food product NFts to the recommendations in the 2003 Nutrition Labelling regulation (Schedule M) reference amounts, the Canadian Food Inspection Agency (CFIA) ranges, and Canada's Food Guide recommendations. An additional objective was to determine if food and beverage products that report smaller serving sizes have a higher calorie density, compared to similar products with a larger serving size. METHODS: Data for 10,487 products were retrieved from the 2010 Food Label Information Program (FLIP) database and categorized according to Schedule M categories. Correlations between calorie density and manufacturer stated serving size were tested and the proportion of products meeting recommendations were tabulated. RESULTS: 35% of products had serving sizes on the NFt that were smaller than the Schedule M reference amount and 23% exceeded the reference amount. 86% of products fell within the CFIA's recommended serving size ranges; however, 70% were within the lower-half of the range. Several bread and juice categories exceeded CFG's recommendations, while several dairy product categories were smaller than the recommendations. Of the 50 Schedule M sub-categories analyzed, 31 (62%) exhibited a negative correlation between serving size and calorie density. CONCLUSION: While most products fell within the CFIA's recommended serving size ranges, there was a tendency for products with a higher calorie density to list smaller serving sizes.

Simplifying mental math: Changing how added sugars are displayed on the nutrition facts label can improve consumer understanding.

BACKGROUND: Proposed variations to Nutrition Facts Labels (NFL) have included the display of added sugars (AS) content, but its impact on consumer understanding is poorly understood. OBJECTIVE: To examine the degree to which different formats for displaying AS influence consumer understanding, perceptions, and purchase intentions. DESIGN: Randomized-controlled online experiment. PARTICIPANTS: A sample of 2509 U.S adults. INTERVENTION: Participants were randomized to 1 of 8 conditions and viewed 10 food or beverage images with either: (1) no label (control); (2) the current NFL (without AS); (3) the proposed NFL without AS; or the proposed NFL with AS in (4) grams, (5) grams and teaspoons, (6) grams and percent Daily Value (%DV), (7) grams with high/medium/low text, or (8) grams with high/medium/low text and %DV. MAIN OUTCOME MEASURES & STATISTICAL ANALYSIS: ANCOVAs compared scores on quizzes that assessed the accuracy of judgments about AS, overall nutrition understanding and purchase intentions. RESULTS: Presenting AS in grams plus high/medium/low text with and without %DV led to the highest AS understanding scores (85% and 83% correct, respectively) compared to 70% correct when AS was not on the label or was displayed in grams only (74% correct). Displaying AS in teaspoons did not significantly improve understanding beyond grams alone. Consumers were best able to determine which of two products was healthier when AS was presented as %DV (68% correct) versus displayed in grams alone (60% correct), but %DV did not differ from high/medium/low text or teaspoons. None of the labels influenced purchase intentions relative to no label. CONCLUSION: Displaying AS on the NFL in grams with high/medium/low text, %DV, or the combination of the two, improved consumer understanding more than presenting it in grams or teaspoons.

Health literacy, literacy, numeracy and nutrition label understanding and use: a scoping review of the literature.

BACKGROUND: Low health literacy, literacy and numeracy have been identified as barriers to consumer understanding and the interpretation of nutrition-related information. To inform policy and dietetic practice, we examined the extent, range and nature of research on empirical relationships between health literacy, literacy or numeracy and the understanding and use of nutrition labels. METHODS: A scoping review of the literature was conducted. A search of eight databases on 15 April 2014 and 26 May 2016 returned 651 and 173 records, respectively. After de-duplication and two levels of relevance screening, 16 studies were deemed eligible for inclusion in the present review. RESULTS: The majority of studies were conducted in the USA and focused primarily on the use of back-of-pack nutrition labels. Empirical relationships reported between health literacy and nutrition label use were inconsistent and, in some cases, contradictory. The findings from studies examining empirical relationships between literacy, numeracy and nutrition label use suggest that consumers with lower literacy and numeracy: (i) differ from those with higher levels in some of the judgements that they make about food and (ii) may benefit from interventions designed to improve their understanding and use of nutrition label information. Measurement-related issues were identified, such as a reliance on self-reports of nutrition label use, as well as a lack of independence between some measures of health literacy and nutrition label understanding and use. CONCLUSIONS: The empirical relationships between health literacy, literacy, numeracy and nutrition label understanding and use have not been well-studied. Additional attention is needed regarding the measurement-related issues identified in the present review.

Effects of plain packaging, warning labels, and taxes on young people's predicted sugar-sweetened beverage preferences: an experimental study.

BACKGROUND: Consumption of sugar-sweetened beverages (SSBs) is associated with increased risk of obesity, diabetes, heart disease and dental caries. Our aim was to assess the effects of plain packaging, warning labels, and a 20 % tax on predicted SSB preferences, beliefs and purchase probabilities amongst young people. METHODS: A 2 × 3 × 2 between-group experimental study was conducted over a one-week period in August 2014. Intervention scenarios were delivered, and outcome data collected, via an anonymous online survey. Participants were 604 New Zealand young people aged 13-24 years who consumed soft drinks regularly. Participants were randomly allocated using a computer-generated algorithm to view one of 12 experimental conditions, specifically images of branded versus plain packaged SSBs, with either no warning, a text warning, or a graphic warning, and with or without a 20 % tax. Participant perceptions of the allocated SSB product and of those who might consume the product were measured using seven-point Likert scales. Purchase probabilities were measured using 11-point Juster scales. RESULTS: Six hundred and four young people completed the survey (51 % female, mean age 18 (SD 3.4) years). All three intervention scenarios had a significant negative effect on preferences for SSBs (plain packaging: F (6, 587) = 54.4, p <0.001; warning label: F (6, 588) = 19.8, p <0.001; 20 % tax: F (6, 587) = 11.3, p <0.001). Plain packaging and warning labels also had a significant negative impact on reported likelihood of purchasing SSB's (p = <0.001). A 20 % tax reduced participants' purchase probability but the difference was not statistically significant (p = 0.2). CONCLUSIONS: Plain packaging and warning labels significantly reduce young people's predicted preferences for, and reported probability of purchasing, SSBs.

High variation in manufacturer-declared serving size of packaged discretionary foods in Australia.

Despite the potential of declared serving size to encourage appropriate portion size consumption, most countries including Australia have not developed clear reference guidelines for serving size. The present study evaluated variability in manufacturer-declared serving size of discretionary food and beverage products in Australia, and how declared serving size compared with the 2013 Australian Dietary Guideline (ADG) standard serve (600 kJ). Serving sizes were obtained from the Nutrition Information Panel for 4466 packaged, discretionary products in 2013 at four large supermarkets in Sydney, Australia, and categorised into fifteen categories in line with the 2013 ADG. For unique products that were sold in multiple package sizes, the percentage difference between the minimum and the maximum serving size across different package sizes was calculated. A high variation in serving size was found within the majority of food and beverage categories - for example, among 347 non-alcoholic beverages (e.g. soft drinks), the median for serving size was 250 (interquartile range (IQR) 250, 355) ml (range 100-750 ml). Declared serving size for unique products that are available in multiple package sizes also showed high variation, particularly for chocolate-based confectionery, with median percentage difference between minimum and maximum serving size of 183 (IQR 150) %. Categories with a high proportion of products that exceeded the 600 kJ ADG standard serve included cakes and muffins, pastries and desserts (≥74 % for each). High variability in declared serving size may confound interpretation and understanding of consumers interested in standardising and controlling their portion selection. Future research is needed to assess if and how standardising declared serving size might affect consumer behaviour.

Correlates of nutrition label use among college students and young adults: a review.

OBJECTIVE: Nutrition labels are an essential source for consumers to obtain nutrition-related information on food products and serve as a population-level intervention with unparalleled reach. The present study systematically reviewed existing evidence on the correlates of nutrition label use among college students and young adults. DESIGN: Keyword and reference searches were conducted in PubMed, EBSCO, PsycInfo, Cochrane Library and Web of Science. Inclusion criteria included: study design (randomized controlled trial, cohort study, pre-post study or cross-sectional study); population (college students and young adults 18-30 years old); main outcome (nutrition label use); article type (peer-reviewed publication); and language (English). SETTING: College/university. SUBJECTS: College students and young adults. RESULTS: Sixteen studies based on data from college surveys in four countries (USA, UK, Canada, South Korea) were identified from keyword and reference search. Reported prevalence of nutrition label use varied substantially across studies; a weighted average calculation showed 36·5 % of college students and young adults reported using labels always or often. Females were more likely to use nutrition labels than males. Nutrition label use was found to be associated with attitudes towards healthy diet, beliefs on the importance of nutrition labels in guiding food selection, self-efficacy, and nutrition knowledge and education. CONCLUSIONS: The impact of nutrition labelling on food purchase and intake could differ by population subgroups. Nutrition awareness campaigns and education programmes may be important mechanisms for promoting nutrition label use among college students and young adults. Future research is warranted to assess the role of label use on improved dietary decisions.

The role of nutrition labels and advertising claims in altering consumers' evaluation and choice.

Despite policy efforts, consumers' well-informed healthful choice is a challenge. Due to increasing number of benefit claims advertising taste or health front of pack (FOP), consumers face the dilemma to trade taste for health. To understand the mechanisms underlying food evaluation, this study investigates the health-pleasure trade-off and its effect on consumers' choice. 240 EU consumers took part in a taste experiment, after being presented with the product FOP. Half of the products carried a nutrition label FOP, respectively, reduced fat for potato chips, reduced sugar for cereal bars. Further, one third of the products carried health benefit claim, one third taste benefit claim, and one third no additional claim FOP. Attention to information and its effect on experienced taste, health perception and the buying intention were measured. The results show that the message displayed FOP altered consumers evaluation and choice. The effectiveness of the FOP message further depended on consumers' health motivation and the healthfulness perception of carrier products. The outcomes are summarized in a framework of health-pleasure trade-off. Current findings call for the establishment of standards to avoid the use of misleading information FOP.

The effects of nutrition knowledge on food label use. A review of the literature.

Nutrition information on food labels is an important source of nutrition information but is typically underutilized by consumers. This review examined whether consumer nutrition knowledge is important for communication of nutrition information through labels on packaged foods. A cognitive processing model posits that consumers with prior knowledge are more likely to use label information effectively, that is, focus on salient information, understand information, and make healthful decisions based on this information. Consistent with this model, the review found that nutrition knowledge provides support for food label use. However, nutrition knowledge measures varied widely in terms of the dimensions they included and the extensiveness of the assessment. Relatively few studies investigated knowledge effects on the use of ingredient lists and claims, compared to nutrition facts labels. We also found an overreliance on convenience samples relying on younger adults, limiting our understanding of how knowledge supports food label use in later life. Future research should 1) investigate which dimensions, or forms, of nutrition knowledge are most critical to food label use and dietary decision making and 2) determine whether increases in nutrition knowledge can promote great use of nutrition information on food labels.

Front of Pack Labels Enhance Attention to Nutrition Information in Novel & Commercial Brands.

OBJECTIVES: 1) To assess whether Front-of-Pack (FOP) nutrition labels garner attention more readily than more complete, mandated nutrition information (the Nutrition Facts Panel (NFP), required in the US), and 2) To determine whether label design characteristics, specifically, color coding and/or coding with facial icons, increase attention to the FOP label. METHODS: In two experiments, we tracked the allocation of attention while participants (n=125) viewed novel and commercial packages with varied FOP designs using a change detection methodology. RESULTS: We found empirical evidence that FOP labels are attended more often, and earlier, than the currently mandated NFP, and that this benefit is due both to its placement on the front of the package and to the design characteristics of the FOP. Specifically, the use of color in FOPs increased attention to the label, but there was no evidence that coding information via facial icons impacted attention. CONCLUSIONS: Our work supports a growing body of evidence supporting the use of FOP labels to attract attention to nutritional information. Findings may be relevant to inform policy decisions on labeling standards.

Attention mediates the effect of nutrition label information on consumers' choice. Evidence from a choice experiment involving eye-tracking.

In two eye-tracking studies, we explored whether and how attention to nutrition information mediates consumers' choice. Consumers had to select either the healthiest option or a product of their preference within an assortment. On each product a particular label (Choices logo, monochrome GDA label, or color-coded GDA label) communicated the product's nutrient profile. In study 1, participants had to select from 4 products differentiated, in addition to the nutrition information, by flavor (strawberry, muesli, apple, chocolate; varied within participants) and brand (local vs. global, varied between participants). Study 2 further explored brand effect within-participants, and thus only 2 flavors (strawberry, chocolate) were presented within an assortment. Actual choice made, response time and eye movements were recorded. Respondents fixated longer and more often on products with color-coded GDAs label than on products with monochrome GDAs or Choices logo. A health goal resulted in longer and more frequent fixations in comparison to a preference goal. Products with color-coded and monochrome GDAs had the highest likelihood of being chosen, and this effect was related to the attention-getting property of the label (irrespective of brand and flavor effects). The product fixated most had the highest likelihood of being chosen. These results suggest that attention mediates the effect of nutrition labels on choice.