Impact of front-of-pack 'traffic-light' nutrition labelling on consumer food purchases in the UK

Front-of-pack ‘traffic-light’ nutrition labelling has been widely proposed as a tool to improve public health nutrition. This study examined changes to consumer food purchases after the introduction of traffic-light labels with the aim of assessing the impact of the labels on the ‘healthiness’ of foods purchased. The study examined sales data from a major UK retailer in 2007. We analysed products in two categories (‘ready meals’ and sandwiches), investigating the percentage change in sales 4 weeks before and after traffic-light labels were introduced, and taking into account seasonality, product promotions and product life-cycle. We investigated whether changes in sales were related to the healthiness of products. All products that were not new and not on promotion immediately before or after the introduction of traffic-light labels were selected for the analysis (n = 6 for ready meals and n = 12 for sandwiches). For the selected ready-meals, sales increased (by 2.4% of category sales) in the 4 weeks after the introduction of traffic-light labels, whereas sales of the selected sandwiches did not change significantly. Critically, there was no association between changes in product sales and the healthiness of the products. This short-term study based on a small number of ready meals and sandwiches found that the introduction of a system of four traffic-light labels had no discernable effect on the relative healthiness of consumer purchases. Further research on the influence of nutrition signposting will be needed before this labelling format can be considered a promising public health intervention.

Experimental stress analysis of a steel light truck wheel

The development of a new automotive wheel requires extensive testing and possible design changes. The wheel investigated had three major changes during development. These three designs were subjected to a stress analysis, by experimental methods, to allow a comparison to be made between each design. The experimental program tested the wheels under conditions designed to simulate the loading of the front wheels whilst cornering. A loading frame was built for this purpose and all testing was performed statically by multiple loading for different directions of bending moment. Brittle lacquer coatings were used on each wheel to highlight high strain areas and indicate optimum locations for the placement of strain gauges. The strain gauges were then used to evaluate the strains. Wheel stud loads were also monitored via strain gauges applied to two of the wheel studs. All data was stored on magnetic tapes and the stress analysis performed by means of a minicomputer. The results of the stress analysis showed quantitatively the improvement in design from the first to the third wheel design. The analysis of the stud loads and their variation during loading indicated the optimum wheel mounting face geometry to ensure nut loosening would not occur in service.

'Traffic-light' nutrition labelling and 'junk-food' tax : a modelled comparison of cost-effectiveness for obesity prevention

Introduction: Cost-effectiveness analyses are important tools in efforts to prioritise interventions for obesity prevention.
Modelling facilitates evaluation of multiple scenarios with varying assumptions. This study compares the cost-effectiveness of
conservative scenarios for two commonly proposed policy-based interventions: front-of-pack ‘traffic-light’ nutrition labelling
(traffic-light labelling) and a tax on unhealthy foods (‘junk-food’ tax).
Methods: For traffic-light labelling, estimates of changes in energy intake were based on an assumed 10% shift in consumption
towards healthier options in four food categories (breakfast cereals, pastries, sausages and preprepared meals) in 10% of adults. For the ‘junk-food’ tax, price elasticities were used to estimate a change in energy intake in response to a 10% price increase in seven food categories (including soft drinks, confectionery and snack foods). Changes in population weight and body mass index by sex were then estimated based on these changes in population energy intake, along with subsequent impacts on disability-adjusted life years (DALYs). Associated resource use was measured and costed using pathway analysis, based on a health sector perspective (with some industry costs included). Costs and health outcomes were discounted at 3%. The cost-effectiveness of each intervention was modelled for the 2003 Australian adult population.
Results: Both interventions resulted in reduced mean weight (traffic-light labelling: 1.3 kg (95% uncertainty interval (UI): 1.2;
1.4); ‘junk-food’ tax: 1.6 kg (95% UI: 1.5; 1.7)); and DALYs averted (traffic-light labelling: 45 100 (95% UI: 37 700; 60 100);
‘junk-food’ tax: 559 000 (95% UI: 459 500; 676 000)). Cost outlays were AUD81 million (95% UI: 44.7; 108.0) for traffic-light
labelling and AUD18 million (95% UI: 14.4; 21.6) for ‘junk-food’ tax. Cost-effectiveness analysis showed both interventions were
‘dominant’ (effective and cost-saving).
Conclusion: Policy-based population-wide interventions such as traffic-light nutrition labelling and taxes on unhealthy foods are
likely to offer excellent ‘value for money’ as obesity prevention measures.

Consumers' responses to front-of-pack labels that vary by interpretive content

Previous research has shown that front-of-pack labels (FoPLs) can assist people to make healthier food choices if they are easy to understand and people are motivated to use them. There is some evidence that FoPLs providing an assessment of a food's health value (evaluative FoPLs) are easier to use than those providing only numerical information on nutrients (reductive FoPLs). Recently, a new evaluative FoPL (the Health Star Rating (HSR)) has been introduced to Australia and New Zealand. The HSR features a summary indicator, differentiating it from many other FoPLs being used around the world. The aim of this study was to understand how consumers of all ages use and make sense of reductive FoPLs and evaluative FoPLs including evaluative FoPLs with and without summary indicators. Ten focus groups were conducted in Perth, Western Australia with adults (n = 50) and children aged 10–17 years (n = 35) to explore reactions to one reductive FoPL (the Daily Intake Guide), an existing evaluative FoPL (multiple traffic lights), and a new evaluative FoPL (the HSR). Participants preferred the evaluative FoPLs over the reductive FoPL, with the strongest preference being for the FoPL with the summary indicator (HSR). Discussions revealed the cognitive strategies used when interpreting each FoPL (e.g., using cut offs, heuristics, and the process of elimination), which differed according to FoPL format. Most participants reported being motivated to use the evaluative FoPLs (particularly the HSR) to make choices about foods consumed as part of regular daily meals, but not for discretionary foods consumed as snacks or deserts. The findings provide further evidence of the potential utility of evaluative FoPLs in supporting healthy food choices and can assist policy makers in selecting between alternative FoPL formats.

The combined effect of front-of-pack nutrition labels and health claims on consumers' evaluation of food products

The majority of studies examining the effect of nutrition information on food packets (such as the nutrition information panel (NIP), front-of-pack labels (FoPLs) and health claims) have examined each in isolation, even though they often occur together. This study investigated the relationship between FoPLs and health claims since (i) they both appear on the front of packs and typically receive more attention from consumers than the NIP, (ii) they can convey contradictory messages (i.e., health claims provide information on nutrients that are beneficial to health while FoPLs provide information on nutrients associated with increased health risks) and (iii) there is currently scant research on how consumers trade off between these two sources of information. Ten focus groups (n = 85) explored adults' and children's reactions when presented with both a FoPL (the Daily Intake Guide, Multiple Traffic Lights, or the Health Star Rating) and a health claim (nutrient content, general-level-, or high-level). A particular focus was participants' processing of discrepant information. Participants reported that health claims were more likely to be considered during product evaluations if they were perceived to be trustworthy, relevant and informative. Trust and ease of interpretation were most important for FoPLs, which were more likely than health claims to meet criteria and be considered during product evaluation (especially the Health Star Rating and Multiple Traffic Lights). Results indicate that consumers generally find FoPLs more useful than health claims.