The impact of adding front-of-package sodium content labels to grocery products: an experimental study

The Potential Effectiveness of Front-of-Pack Nutrition Labeling for Improving Population Diets

Nutrition labeling on the front of food packages can support more healthful purchase decisions and encourage favorable reformulation. This systematic literature review applied Cochrane methods to synthesize and appraise the evidence on the effectiveness of front-of-pack labeling (FOPL) on diet-related outcomes and food reformulation to inform policy recommendations. The search was conducted on 11 academic and gray literature databases, from inception to July 2022. Evidence was synthesized using GRADE (Grading of Recommendations, Assessment, Development, and Evaluation), vote counting, and meta-analyses, where appropriate. Overall, 221 articles were included in the review. The randomized controlled trial evidence suggested that, compared with when no FOPL was present, FOPL likely improved consumer understanding of the nutritional quality/content of foods (moderate certainty of evidence), and the healthfulness of food choices (moderate certainty) and purchases (moderate certainty). Interpretive FOPL had a greater effect on these outcomes compared with noninterpretive systems (moderate certainty). There was inconsistency in the best-performing interpretive FOPL system.

Front-of-package nutrition labeling as a driver for healthier food choices: Lessons learned and future perspectives

This work aims to provide a comprehensive overview of the use of front-of-package nutritional labeling (FOPL), identify and characterize the major existing FOPL systems, examine the impact of FOPL systems on consumer behavior, and discuss future perspectives. The searched databases were PubMed, Scopus, and Web of Science, and papers in English, Portuguese, Spanish, and French were considered. The integrative review method was used, comprising 68 papers. The FOPL system from more than 47 countries from North America, South America, Africa, Europe, Australia, and Asia was included in this study. The two main ways to characterize FOPL are the level of interpretation and the type of information provided. Interpretive schemes (such as warning labels, multiple traffic lights, and Nutri-Score) appear to lead to better consumer understanding and support healthier food purchases. However, due to the differences among the results and the specificity of the contexts in which they are used, it is impossible to define one FOPL interpretation scheme superior to the others. Some potential factors that influence the effectiveness of FOPL on consumer attitudes have been identified, such as food taste, as a major intrinsic factor. Extrinsic factors, such as price, food category, cultural diversity, politics, and economics, were also relevant. The lack of availability of similar alternatives, lack of understanding of the importance of FOPL, and lower levels of income and education were also some cognitive and social aspects impairing FOPL effectiveness. Prospects for the United States, Europe, Brazil, Colombia, and Argentina were discussed.

Reducing salt intake: a systematic review and meta-analysis of behavior change interventions in adults

CONTEXT

Prolonged high salt (sodium) intake can increase the risk of hypertension and cardiovascular disease. Behavioral interventions may help reduce sodium intake at the population level.

OBJECTIVE

The effectiveness of behavior change interventions to reduce sodium intake in adults was investigated in this systematic review and meta-analysis.

DATA SOURCE

The PubMed, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and EMBASE databases were searched.

DATA EXTRACTION

Narrative synthesis and random-effects meta-analyses were used to determine intervention efficacy. A total of 61 trials (46 controlled trials and 15 quasi-experimental studies) were included.

RESULTS

Behavior change interventions resulted in significant improvements in salt consumption behavior (eg, decrease in purchase of salty foods; increase in use of salt substitutes), leading to reductions in sodium intake as measured by urinary sodium in 32 trials (N = 7840 participants; mean difference, -486.19 mg/d [95%CI, -669.44 to -302.95]; P < 0.001; I2 = 92%) and dietary sodium in 19 trials (N = 3750 participants; mean difference -399.86 mg/d [95%CI, -581.51 to -218.20]; P < 0.001; I2 = 96%), equivalent to a reduction of >1 g of salt intake daily. Effects were not significantly different based on baseline sodium intakes, blood pressure status, disease status, the use of behavior change theories, or the main method of intervention delivery (ie, online vs face-to-face).

CONCLUSION

Behavior change interventions are effective at improving salt consumption practices and appear to reduce salt intake by >1 g/d.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42020185639.

Objective understanding of the Nutri-score front-of-pack label by European consumers and its effect on food choices: an online experimental study

Background

The effectiveness of Front-of-Pack nutrition Labels (FoPLs) may be influenced by national context. In light of the ongoing efforts to harmonize FoPLs across Europe, this study aimed to compare the effectiveness of five FoPLs (Health Star Rating system, Multiple Traffic Lights, Nutri-Score, Reference Intakes, Warning symbols) on consumer understanding and food choice in 12 European countries.

Methods

In 2018–2019, for three food categories, approximately 1000 participants per country were asked to select which food they would prefer to purchase between three products with distinct nutritional quality profiles, and then to rank the products by nutritional quality. Participants (N = 12,391 in total) completed these tasks first with no FoPL and then, after randomization to one of the five FoPLs, with a FoPL on the food packages. Associations between FoPLs and change in (i) nutritional quality of food choices and (ii) ability to correctly rank the products by nutritional quality were assessed with logistic regression models adjusted for sociodemographic and lifestyle characteristics of participants, conducted overall and by country.

Findings

Compared with the Reference Intakes, the Nutri-Score (OR = 3.23[2.75–3.81]; p < 0.0001), followed by the Multiple Traffic Lights (OR = 1.68[1.42–1.98]; p < 0.0001), was the most effective FoPL in helping consumers identify the foods’ nutritional quality, overall and in each of the 12 countries. Differences between FoPLs regarding food choice modifications were smaller, but the effect of the Nutri-Score seemed slightly higher in eliciting healthier food choices overall compared with the Reference Intakes, followed by the Warning symbols, the Multiple Traffic Lights and the Health Star Rating system.

Interpretation

In the context of FoPL harmonization in Europe, these findings from an online experiment provide insights into the Nutri-Score’s effectiveness on European consumers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-020-01053-z.

Effectiveness of Different Front-of-Pack Nutrition Labels among Italian Consumers: Results from an Online Randomized Controlled Trial

In Italy, discussions are currently ongoing to implement a front-of-pack nutrition label (FoPL) while a growing number of European countries are adopting the Nutri-Score. The effectiveness of the Nutri-Score among Italian consumers requires further investigation. This study compared five FoPLs among Italian participants (Health Star Rating system, multiple traffic lights, Nutri-Score, reference intakes, warning symbol) in terms of food choices and understanding of the labels by consumers. In 2019, 1032 Italian consumers completed an online survey in which they were asked to select one product they would likely purchase from a set of three foods with different nutrient profiles and then classify the products within the set according to their nutritional quality, first with no label and then with one of the five FoPLs on the pack. While no significant difference across labels was observed for food choices, the Nutri-Score demonstrated the highest overall performance in helping consumers to correctly rank the products according to their nutritional quality compared to the reference intakes (OR = 2.18 (1.50–3.17), p-value < 0.0001). Our results provide new insights on the effectiveness of the Nutri-Score, which would be a relevant tool to inform Italian consumers on the nutritional quality of food products.

That's My Cue to Eat: A Systematic Review of the Persuasiveness of Front-of-Pack Cues on Food Packages for Children vs. Adults

Packaging is increasingly recognized as an essential component of any marketing strategy. Visual and informational front-of-pack cues constitute salient elements of the environment that may influence what and how much someone eats. Considering their overwhelming presence on packaging of non-core foods, front-of-pack cues may contribute to the growing rates of overweight and obesity in children and adults. We conducted a systematic review to summarize the evidence concerning the impact of front-of-pack cues on choices and eating behaviors. Four electronic databases were searched for experimental studies (2009-present). This resulted in the inclusion of 57 studies (in 43 articles). We identified studies on children (3-12 years) and adults (≥ 18 years), but no studies on adolescents (12-18 years). The results suggest that children and adults are susceptible to packaging cues, with most evidence supporting the impact of visual cues. More specifically, children more often choose products with a licensed endorser and eat more from packages portraying the product with an exaggerated portion size. Adults' eating behaviors are influenced by a range of other visual cues, mainly, package size and shape, and less so by informational cues such as labels.

Compared to other front-of-pack nutrition labels, the Nutri-Score emerged as the most efficient to inform Swiss consumers on the nutritional quality of food products

Background

Switzerland, like other high-income countries, is facing a major public health challenge with the increasing burden of non-communicable diseases. Discussions are currently on-going in Switzerland regarding the implementation of a Front-of-Pack nutrition label (FoPL) as a public health measure to guide consumers towards healthier food choices, and the Nutri-Score represents an alternative supported by multiple actors. To date, no studies have investigated the performance of the Nutri-Score among Swiss consumers. This study aimed to compare the response of Swiss consumers to five FoPLs (Health Star Rating system, Multiple Traffic Lights, Nutri-Score, Reference Intakes and Warning symbol) in terms of perception and understanding of these labels and effects on food choices.

Methods

In 2019, 1,088 Swiss consumers were recruited and asked to select one product from among a set of three foods with different nutritional profiles and then classify the products within the sets according to their nutritional quality. Tasks were performed in situations without a label and then with one of the five FoPLs–depending on the group in which they were randomized–on the pack. Finally, participants were questioned on their perceptions regarding the label to which they were exposed.

Results

All FoPLs were favorably perceived, with marginal differences between FoPLs. The Nutri-Score demonstrated the highest percentage of improvement in food choices and the highest overall performance in helping consumers rank the products according to their nutritional quality.

Conclusion

Overall, the Nutri-Score was the most efficient FoPL in informing Swiss consumers of the nutritional quality of food products, and as such could be a useful tool to improve food choices and reduce the burden of chronic diseases in Switzerland.

Selected Predictors of the Importance Attached to Salt Content Information on the Food Packaging (a Study among Polish Consumers)

This paper aims to identify selected antecedents of the importance attached to salt content information (ISCI) placed on food labels, on the basis of a representative survey of 1051 Polish consumers. The study was conducted with the use of the CAWI (Computer Assisted Web Interviews) method in 2018. Quota sampling was applied with reference to the following five criteria: sex, age, education, place of living (urban and rural areas), and region. In a multiple regression model, ISCI depends on the respondent’s: sex, age, evaluation of the quantity of nutrition claims, importance attached to nutrition claims, willingness to pay a price premium for products with nutrition claims, attention paid to health and nutrition claims, agreeing with the opinion that unreliable nutrition claims are a serious problem, evaluation of healthiness of one’s diet, self-rated knowledge about healthy nutrition, buying organic food, and reading front-of-package (FOP) labels during and after the purchase. The strongest effects on the importance attached to salt content information on the food packaging were displayed by the importance of nutrition claims, attention paid to nutrition and health claims, respondent’s age, FOP label reading at home, and agreeing that the use of unreliable nutrition claims is a serious problem.

Modelling the impact of different front-of-package nutrition labels on mortality from non-communicable chronic disease

Background

Front-of-Package nutrition labels (FoPLs) are intended to help reduce the incidence of nutrition-related non-communicable diseases through an improvement in diet quality. FoPLs have been shown to improve the nutritional quality of purchases and have been associated with improved diet quality, which is in turn associated with reduced risk of non-communicable diseases. However, the potential impact of FoPLs on reducing mortality from chronic diseases has never been estimated.

Methods

Data from a laboratory experimental economics test were used to investigate the effects of five different FoPLs (Nutri-Score, Health Star Rating system, Multiple Traffic lights, Reference intakes and SENS (Système d’Etiquetage Nutritionnel Simplifié)) on the nutritional quality of household purchases. The relative differences in nutrient content and composition of food purchases were then applied to dietary intakes using data from an observational study, thus yielding estimates for ‘reference’ and ‘labelled’ diets. A macro-simulation study using the PRIME model was then conducted to estimate the impact of the modification in dietary intake as a result of FoPL use on mortality from diet-related non-communicable diseases.

Results

The use of FoPLs led to a substantial reduction in mortality from chronic diseases. Approximately 3.4% of all deaths from diet-related non-communicable diseases was estimated to be avoidable when the Nutri-Score FoPL was used. The remaining FoPLs likewise resulted in mortality reduction, although to a lesser extent: Health Star Rating system (2.8%), Reference Intakes (1.9%), Multiple Traffic Lights (1.6%), and SENS (1.1%).

Conclusions

FoPLs have the potential to help decrease mortality from diet-related non-communicable diseases, and the Nutri-Score appears to be the most efficient among the five formats tested.

Electronic supplementary material

The online version of this article (10.1186/s12966-019-0817-2) contains supplementary material, which is available to authorized users.

A Meta-Analysis of Food Labeling Effects on Consumer Diet Behaviors and Industry Practices

CONTEXT

The influence of food and beverage labeling (food labeling) on consumer behaviors, industry responses, and health outcomes is not well established.

EVIDENCE ACQUISITION

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. Ten databases were searched in 2014 for studies published after 1990 evaluating food labeling and consumer purchases/orders, intakes, metabolic risk factors, and industry responses. Data extractions were performed independently and in duplicate. Studies were pooled using inverse-variance random effects meta-analysis. Heterogeneity was explored with I2, stratified analyses, and meta-regression; and publication bias was assessed with funnel plots, Begg's tests, and Egger's tests. Analyses were completed in 2017.

EVIDENCE SYNTHESIS

From 6,232 articles, a total of 60 studies were identified, including 2 million observations across 111 intervention arms in 11 countries. Food labeling decreased consumer intakes of energy by 6.6% (95% CI= -8.8%, -4.4%, n=31), total fat by 10.6% (95% CI= -17.7%, -3.5%, n=13), and other unhealthy dietary options by 13.0% (95% CI= -25.7%, -0.2%, n=16), while increasing vegetable consumption by 13.5% (95% CI=2.4%, 24.6%, n=5). Evaluating industry responses, labeling decreased product contents of sodium by 8.9% (95% CI= -17.3%, -0.6%, n=4) and artificial trans fat by 64.3% (95% CI= -91.1%, -37.5%, n=3). No significant heterogeneity was identified by label placement or type, duration, labeled product, region, population, voluntary or legislative approaches, combined intervention components, study design, or quality. Evidence for publication bias was not identified.

CONCLUSIONS

From reviewing 60 intervention studies, food labeling reduces consumer dietary intake of selected nutrients and influences industry practices to reduce product contents of sodium and artificial trans fat.

Objective Understanding of Front-of-Package Nutrition Labels: An International Comparative Experimental Study across 12 Countries

Front-of-Package labels (FoPLs) are efficient tools for increasing consumers' awareness of foods' nutritional quality and encouraging healthier choices. A label's design is likely to influence its effectiveness; however, few studies have compared the ability of different FoPLs to facilitate a consumer understanding of foods' nutritional quality, especially across sociocultural contexts. This study aimed to assess consumers' ability to understand five FoPLs [Health Star Rating system (HSR), Multiple Traffic Lights (MTL), Nutri-Score, Reference Intakes (RIs), and Warning symbol] in 12 different countries. In 2018, approximately 1000 participants per country were recruited and asked to rank three sets of label-free products (one set of three pizzas, one set of three cakes, and one set of three breakfast cereals) according to their nutritional quality, via an online survey. Participants were subsequently randomised to one of five FoPL conditions and were again asked to rank the same sets of products, this time with a FoPL displayed on pack. Changes in a participants' ability to correctly rank products across the two tasks were assessed by FoPL using ordinal logistic regression. In all 12 countries and for all three food categories, the Nutri-Score performed best, followed by the MTL, HSR, Warning symbol, and RIs.

Awareness, understanding and use of sodium information labelled on pre-packaged food in Beijing:a cross-sectional study

Background

Nutrition labelling has been mandatory for pre-packaged foods since 2013 in China, and sodium is one of the nutrients required for display on the nutritional information panel (NIP). This study aimed to estimate the awareness, understanding of, and use of sodium labelling information among the population in China.

Methods

A cross-sectional survey was carried out in urban Beijing in 2016 on pre-packaged foods. The researchers randomly selected 380 residents from four convenient but disconnected communities and 370 shoppers from four supermarkets owned by different companies and conducted face-to-face interviews. Questions on nutritional knowledge, health attitude, understanding and use of nutritional labels as well as other related factors were assessed.

Results

All of the 380 community residents and 308 of the 370 supermarket shoppers successfully completed the survey. Of those 688 respondents, 91.3% understood that excessive salt intake was harmful, 19.5% were aware that sodium content is listed on the NIP, 5.5% understood the meaning of NRV% (Percentage of Nutrient Reference Values), 47.7% did not know the relationship between sodium and salt, and 12.6% reported they frequently read the label when shopping. Factors for why people were more likely to choose a product because of its low level of salt shown on the label include income level and their level of awareness of the link between salt and diet.

Conclusions

Although the participants had a good understanding of the harmful effects of salt, the awareness, understanding and use of sodium labels was very low in Beijing, and even worse nationwide. Efforts should be taken to educate the public to understand and use the NIP better and design clearer ways of displaying such information, such as front-of pack (FoP) labelling or health-related smartphone applications to improve health and help people make better food choices.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-018-5396-7) contains supplementary material, which is available to authorized users.

Impact of food labelling systems on food choices and eating behaviours: a systematic review and meta-analysis of randomized studies

Food labels are considered a crucial component of strategies tackling unhealthy diets and obesity. This study aims at assessing the effectiveness of food labelling in increasing the selection of healthier products and in reducing calorie intake. In addition, this study compares the relative effectiveness of traffic light schemes, Guideline Daily Amount and other food labelling schemes. A comprehensive set of databases were searched to identify randomized studies. Studies reporting homogeneous outcomes were pooled together and analysed through meta-analyses. Publication bias was evaluated with a funnel plot. Food labelling would increase the amount of people selecting a healthier food product by about 17.95% (confidence interval: +11.24% to +24.66%). Food labelling would also decrease calorie intake/choice by about 3.59% (confidence interval: -8.90% to +1.72%), but results are not statistically significant. Traffic light schemes are marginally more effective in increasing the selection of healthier options. Other food labels and Guideline Daily Amount follow. The available evidence did not allow studying the effects of single labelling schemes on calorie intake/choice. Findings of this study suggest that nutrition labelling may be an effective approach to empowering consumers in choosing healthier products. Interpretive labels, as traffic light labels, may be more effective.

Using traffic light labels to improve food selection in recreation and sport facility eating environments

Many recreation and sports facilities have unhealthy food environments, however managers are reluctant to offer healthier foods because they perceive patrons will not purchase them. Preliminary evidence indicates that traffic light labeling (TLL) can increase purchase of healthy foods in away-from-home food retail settings. We examined the effectiveness of TLL of menus in promoting healthier food purchases by patrons of a recreation and sport facility concession, and among various sub-groups. TLL of all menu items was implemented for a 1-week period and sales were assessed for 1-week pre- and 1-week post-implementation of TLL (n = 2101 transactions). A subset of consumers completed a survey during the baseline (n = 322) and intervention (n = 313) periods. We assessed change in the proportion of patrons' purchases that were labeled with green, yellow and red lights from baseline to the TLL intervention, and association with demographic characteristics and other survey responses. Change in overall revenues was also assessed. There was an overall increase in sales of green (52.2% to 55.5%; p < 0.05) and a reduction in sales of red (30.4% to 27.2%; p < 0.05) light items from baseline to the TLL period. The effectiveness of TLL did not differ according to any of the demographic or other factors examined in the survey. Average daily revenues did not differ between the baseline and TLL periods. TLL of menus increased purchase of healthy, and reduced purchase of unhealthy foods in a publicly funded recreation and sport facility, with no loss of revenue. Policymakers should consider extending menu labeling laws to public buildings such as recreation and sports facilities to promote selection of healthier items.

The Influence of Nutrition Labeling and Point-of-Purchase Information on Food Behaviours

Point-of-purchase information on packaged food has been a highly debated topic. Various types of nutrition labels and point-of-purchase information have been studied to determine their ability to attract consumers' attention, be well understood and promote healthy food choices. Country-specific regulatory and monitoring frameworks have been implemented to ensure reliability and accuracy of such information. However, the impact of such information on consumers' behaviour remains contentious. This review summarizes recent evidence on the real-world effectiveness of nutrition labels and point-of-purchase information.

Sociodemographic differences in the comprehension of nutritional labels on food products

OBJECTIVE

To examine comprehension of nutrition labels across sociodemographic groups using a measure of health literacy.

METHODS

Cross-sectional survey of a community sample of adults including an adapted version of the Newest Vital Sign for Canadian Nutrition Facts table on prepackaged grocery products, including numerical conversion questions for calorie content and percent daily value.

RESULTS

Approximately two thirds of participants were able to correctly identify calorie content and percent daily value from the nutrition label. Participants with higher education and higher income, those aged ≤ 64 years, and those who look at nutritional facts or calories were significantly more likely to estimate the correct calorie content. Participants were significantly more likely to correctly identify percent daily value if they reported higher education, higher income, and white ethnicity.

CONCLUSIONS AND IMPLICATIONS

Approximately one third of participants could not comprehend basic information on Canadian nutrition labels. Lower socioeconomic status was associated with poorer performance.

Understanding of sodium content labeled on food packages by Japanese people

Salt reduction is one of the most important lifestyle modifications for the prevention of hypertension. The health promotion law regulates the labeling of the nutrient content of food in Japan and, the level of sodium, not salt (sodium chloride), has to be printed on the labels of manufactured foods. In order to control their salt intake, consumers need to apply a conversion factor to the sodium levels listed on the labels to obtain the salt equivalent. However, it is not known whether people have the knowledge appropriate for making the conversion. We carried out a questionnaire survey at the 7th National Shokuiku (food education) Conference in 2012, asking subjects to determine the salt equivalent of 1000 mg of sodium on food labels. We also asked about the target values of salt reduction in grams in the Dietary Reference Intakes for Japanese 2010 (DRI2010) and the Guidelines for Management of Hypertension 2009 by the Japanese Society of Hypertension (JSH2009). We analyzed the data from 683 respondents (169 men and 514 women); only 13.3% of respondents gave a correct answer for the salt equivalent of 1000 mg of sodium (2.50-2.60 g), whereas 61.8 and 40.4% of respondents chose the correct target values for salt reduction according to DRI2010 and JSH2009, respectively. In conclusion, few people could convert sodium content to salt, which suggested difficulty in using food labels to control their salt intake. Salt content in grams, not sodium content, should be labeled on food packages for effective salt reduction and prevention of hypertension.