What is the impact of increasing the prominence of calorie labelling? A stepped wedge randomised controlled pilot trial in worksite cafeterias

Food for thought: Reinforced learning and recall of physical activity calorie equivalent (PACE) and numerical calorie content in an associative learning task

Calorie overconsumption has been proposed as a critical contributing factor to rising obesity rates. To combat this health issue, governments and policymakers have suggested implementing numerical caloric content labels. Alternatively, physical activity calorie equivalent (PACE) labels are being proposed as an easier-to-understand metric, representing the amount of physical activity required to burn off calorie content. This study examined individuals' ability to correctly estimate either the numerical caloric content or the PACE values of food images in an associative learning task. Moreover, it assessed whether this knowledge was learned and retained over time. One hundred and ninety-one participants were instructed to estimate either the numerical caloric content or PACE values of thirty food images. To facilitate learning, feedback on the correct number of calories or PACE values was provided during the first session (Time 1). To assess retention, people re-estimated numerical caloric content or PACE values of the same food pictures three days later (Time 2) and seven days later (Time 3), where feedback was not provided. Results showed that participants in both groups improved their estimations using feedback, with people being consistently more accurate when estimating numerical calorie content. Yet, our results also suggest that participants consolidated their knowledge of PACE values over time. Finally, our findings show that hunger moderates individuals' estimation ability, where hungrier people are less accurate than satiated ones. The results contribute to our understanding of how consumers process, estimate, and learn PACE labels versus numerical caloric content, and provide valuable information for researchers and policymakers to develop and implement nutritional labels as a health strategy.

Assessing public perception and awareness of UK mandatory calorie labeling in the out-of-home sector: Using Twitter and Google trends data

Objectives

In 2021 the UK government announced a new obesity policy requiring large out-of-home food outlets to provide mandatory in-store calorie labeling on food and drink items. Public acceptability and engagement with obesity policies could influence the level of impact on wider public health particularly with population-level policies such as calorie labeling. This study aimed to examine public responses and awareness of the policy using social media (Twitter) comments and Google trends data.

Methods

This study examined responses to social media posts on Twitter (tweets) from the UK Department of Health and Social Care detailing the policy, implementation date and post-implementation information about the policy's enforcement. The sentiments of the tweets were coded and the number of likes and replies extracted. This study utilized google trends to examine public awareness of the policy by extracting weekly relative search volume for relevant phrases such as "calorie labeling."

Results

From the 276 replies/quote-tweet extracted, the majority expressed a negative sentiment toward the policy (N = 197/71.4%). There were fewer tweets expressing a positive sentiment (N = 25/8.7%) and a neutral/no sentiment (N = 54/19.6%). There was no difference in the number of "likes" or retweets between tweets expressing positive or negative sentiments. Five themes were identified expressing negative sentiments (most common being negative impacts on eating disorders). Google trends data revealed increased searches for "calorie labels/labeling" during the week of the policy enforcement compared to previous weeks in the last 5 years but no significant differences in searches for specific menu calorie labeling.

Conclusions

This analysis revealed negative sentiment toward and increased searching of calorie labeling information during the announcement and implementation of the 2021 mandatory calorie labeling policy in England. A greater understanding of public responses to calorie labeling policies may help tailor future policies and public communication strategies.

Socioeconomic position and the effect of energy labelling on consumer behaviour: a systematic review and meta-analysis

BACKGROUND

There are well documented socioeconomic disparities in diet quality and obesity. Menu energy labelling is a public health policy designed to improve diet and reduce obesity. However, it is unclear whether the impact energy labelling has on consumer behaviour is socially equitable or differs based on socioeconomic position (SEP).

METHODS

Systematic review and meta-analysis of experimental (between-subjects) and pre-post implementation field studies examining the impact of menu energy labelling on energy content of food and/or drink selections in higher vs. lower SEP groups.

RESULTS

Seventeen studies were eligible for inclusion. Meta-analyses of 13 experimental studies that predominantly examined hypothetical food and drink choices showed that energy labelling tended to be associated with a small reduction in energy content of selections that did not differ based on participant SEP (X2(1) = 0.26, p = .610). Effect estimates for higher SEP SMD = 0.067 [95% CI: -0.092 to 0.226] and lower SEP SMD = 0.115 [95% CI: -0.006 to 0.237] were similar. A meta-analysis of 3 pre-post implementation studies of energy labelling in the real world showed that the effect energy labelling had on consumer behaviour did not significantly differ based on SEP (X2(1) = 0.22, p = .636). In higher SEP the effect was SMD = 0.032 [95% CI: -0.053 to 0.117] and in lower SEP the effect was SMD = -0.005 [95% CI: -0.051 to 0.041].

CONCLUSIONS

Overall there was no convincing evidence that the effect energy labelling has on consumer behaviour significantly differs based on SEP. Further research examining multiple indicators of SEP and quantifying the long-term effects of energy labelling on consumer behaviour in real-world settings is now required.

REVIEW REGISTRATION

Registered on PROSPERO (CRD42022312532) and OSF ( https://doi.org/10.17605/OSF.IO/W7RDB ).

Evaluation of physical activity calorie equivalent (PACE) labels' impact on energy purchased in cafeterias: A stepped-wedge randomised controlled trial

BACKGROUND

A recent meta-analysis suggested that using physical activity calorie equivalent (PACE) labels results in people selecting and consuming less energy. However, the meta-analysis included only 1 study in a naturalistic setting, conducted in 4 convenience stores. We therefore aimed to estimate the effect of PACE labels on energy purchased in worksite cafeterias in the context of a randomised study design.

METHODS AND FINDINGS

A stepped-wedge randomised controlled trial (RCT) was conducted to investigate the effect of PACE labels (which include kcal content and minutes of walking required to expend the energy content of the labelled food) on energy purchased. The setting was 10 worksite cafeterias in England, which were randomised to the order in which they introduced PACE labels on selected food and drinks following a baseline period. There were approximately 19,000 workers employed at the sites, 72% male, with an average age of 40. The study ran for 12 weeks (06 April 2021 to 28 June 2021) with over 250,000 transactions recorded on electronic tills. The primary outcome was total energy (kcal) purchased from intervention items per day. The secondary outcomes were: energy purchased from non-intervention items per day, total energy purchased per day, and revenue. Regression models showed no evidence of an overall effect on energy purchased from intervention items, -1,934 kcals per site per day (95% CI -5,131 to 1,262), p = 0.236, during the intervention relative to baseline, equivalent to -5 kcals per transaction (95% CI -14 to 4). There was also no evidence for an effect on energy purchased from non-intervention items, -5 kcals per site per day (95% CI -513 to 504), p = 0.986, equivalent to 0 kcals per transaction (95% CI -1 to 1), and no clear evidence for total energy purchased -2,899 kcals per site (95% CI -5,810 to 11), p = 0.051, equivalent to -8 kcals per transaction (95% CI -16 to 0). Study limitations include using energy purchased and not energy consumed as the primary outcome and access only to transaction-level sales, rather than individual-level data.

CONCLUSION

Overall, the evidence was consistent with PACE labels not changing energy purchased in worksite cafeterias. There was considerable variation in effects between cafeterias, suggesting important unmeasured moderators.

TRIAL REGISTRATION

The study was prospectively registered on ISRCTN (date: 30.03.21; ISRCTN31315776).

Effect of health warning labels on motivation towards energy-dense snack foods: Two experimental studies

Health warning labels (HWLs) show promise in reducing motivation towards energy-dense snack foods. Understanding the underlying mechanisms could optimise their effectiveness. In two experimental studies in general population samples (Study 1 n = 90; Study 2 n = 1382), we compared the effects of HWLs and irrelevant aversive labels (IALs) on implicit (approach) motivation towards unhealthy snacks, using an approach-avoidance task (Study 1), and a manikin task (Study 2). We also assessed explicit motivation towards unhealthy snacks using food selection tasks. We examined whether labelling effects on motivation arose from the creation of outcome-dependent associations between the food and its health consequences or from simple, non-specific aversive associations. Both label types reduced motivation towards snack foods but only when the label was physically present. HWLs and IALs showed similar effects on implicit motivation, although HWLs reduced explicit motivation more than IALs. Thus, aversive HWLs appear to act both through low level associative mechanisms affecting implicit motivation, and by additionally emphasizing explicit causal links to health outcomes thereby affecting explicitly motivated choice behaviours.

Workplace cafeteria and other multicomponent interventions to promote healthy eating among adults: A systematic review

The objective of this review is to evaluate evidence for the effectiveness of workplace cafeteria and other supporting multicomponent interventions to promote healthy eating and reductions in health risks among adults. We conducted an electronic search in EMBASE, CINAHL, EconLit, Ovid, Cochrane, Web of Science and PubMed for English-language articles published from 1985 to July 2019. Studies were original articles reporting the results of workplace cafeteria interventions to promote healthy eating and reduction in health risks. Outcomes were classified as changes in fruit and vegetable intake, health risk indicators, dietary intake, and food sales. Interventions were categorized as interventions targeting food quality or quantity, targeting price, targeting food choice at point of purchase, targeting improved supply, targeting client's information, education or motivation and targeting organization policies. Behavioral change conditions used in interventions were identified using the COM-B system of behavioral change. Results were presented in a narrative summary. A total of 55 studies out of 6285 articles were identified for this review. Several studies used multicomponent interventions and the most featured interventions included interventions targeting food quality or quantity, targeting client's information, education or motivation and targeting food choice at point of purchase. There is evidence that workplace cafeteria and other supporting multicomponent interventions resulted in higher intake of fruit and vegetables, improved dietary intake, improved health outcomes and healthy food sales. The findings of this review have the potential to inform future cafeteria-based and other supporting multicomponent workplace health interventions. The review protocol was not registered in a repository.

Increasing the proportion of healthier foods available with and without reducing portion sizes and energy purchased in worksite cafeterias: protocol for a stepped-wedge randomised controlled trial

BACKGROUND

Overconsumption of energy from food contributes to high rates of overweight and obesity in many populations. A promising set of interventions tested in pilot studies in worksite cafeterias, suggests energy intake may be reduced by increasing the proportion of healthier - i.e. lower energy - food options available, and decreasing portion sizes. The current study aims to assess the impact on energy purchased of i. increasing the proportion of lower energy options available; ii. combining this with reducing portion sizes, in a full trial.

METHODS

A stepped-wedge randomised controlled trial in 19 worksite cafeterias, where the proportion of lower energy options available in targeted food categories (including main meals, snacks, and cold drinks) will be increased; and combined with reduced portion sizes. The primary outcome is total energy (kcal) purchased from targeted food categories using a pooled estimate across all sites. Follow-up analyses will test whether the impact on energy purchased varies according to the extent of intervention implementation.

DISCUSSION

This study will provide the most reliable estimate to date of the effect sizes of two promising interventions for reducing energy purchased in worksite cafeterias.

TRIAL REGISTRATION

The study was prospectively registered on ISRCTN (date: 24.05.19; TRN: ISRCTN87225572; doi: https://doi.org/10.1186/ISRCTN87225572).

Energy (calorie) labelling for healthier selection and consumption of food or alcohol

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To estimate the effect of energy labelling for food (including non‐alcoholic drinks) and alcoholic drinks on healthier selection (with or without purchasing) and consumption. To assess possible modifiers – energy label type, setting and socioeconomic status ‐ of the effect of energy labelling on selection and consumption of food and alcohol.