Sodium and nutrition labelling: a qualitative study exploring New Zealand consumers' food purchasing behaviours

Knowledge, Attitudes and Behaviours Related to Dietary Salt Intake in High-Income Countries: a Systematic Review

PURPOSE OF REVIEW

The purpose of this review was to examine the knowledge, attitudes and behaviours (KAB) related to dietary salt intake among adults in high-income countries.

RECENT FINDINGS

Overall (n = 24 studies across 12 countries), KAB related to dietary salt intake are low. While consumers are aware of the health implications of a high salt intake, fundamental knowledge regarding recommended dietary intake, primary food sources, and the relationship between salt and sodium is lacking. Salt added during cooking was more common than adding salt to food at the table. Many participants were confused by nutrition information panels, but food purchasing behaviours were positively influenced by front of package labelling. Greater emphasis of individual KAB is required from future sodium reduction programmes with specific initiatives focusing on consumer education and awareness raising. By doing so, consumers will be adequately informed and empowered to make healthier food choices and reduce individual sodium intake.

The Digital Education to Limit Salt in the Home Program Improved Salt-Related Knowledge, Attitudes, and Behaviors in Parents

Background

Currently, Australian children and adults are eating too much salt, increasing their risk of cardiovascular-related conditions. Web-based programs provide an avenue to engage the parents of primary schoolchildren in salt-specific messages, which may positively impact their own salt-related knowledge, attitudes, and behaviors (KABs).

Objective

This pilot study aimed to determine whether parents’ salt-related KABs improved following participation in the Digital Education to LImit Salt in the Home (DELISH) Web-based education program.

Methods

The DELISH program was a 5-week, home-delivered, Web-based intervention, with a pre- and posttest design, targeting schoolchildren aged 7 to 10 years and their parents. Parents received weekly Web-based educational newsletters and text messages and completed online pre- and postprogram surveys assessing salt-related KABs. Upon completion of the program, all parents were also invited to complete an online evaluation survey. Changes in KABs outcomes were assessed using McNemar tests and paired t tests.

Results

Of the 80 parents that commenced the program, 73 parents (mean age 41.0, SD 7.0 years; 86% (63/73) females) completed both pre- and postsurveys. Overall, mean score for salt-related knowledge improved (+3.6 [standard error (SE) 0.41] points), and mean behavior score also improved (+4.5 [SE 0.61] points), indicating a higher frequency of engaging in behaviors to reduce salt in the diet, and mean attitude score decreased (−0.7 [SE 0.19] points), representing lower importance of using salt to enhance the taste of food (all P<.001). Following participation, the proportion of parents aware of the daily salt intake recommendation increased from 40% (29/73) to 74% (54/73) (P<.001), and awareness of bread as the main source of salt increased from 58% (42/73) to 95% (69/73) (P<.001). The proportion of parents who agreed that salt should be used in cooking to enhance the flavor of food decreased from 30% (22/73) to 11% (8/73) (P=.002) and the proportion who agreed that sodium information displayed on food labels was difficult to understand decreased from 52% (38/73) to 32% (23/73) (P=.009). There was a reduction in the proportion of parents who reported adding salt during cooking (55% [40/73] vs 41% [30/73]; P=.03) and at the table (32% [23/73] vs 18% [13/73]; P=.002). Of the 16 parents who completed the evaluation survey, 75% (12/16) enjoyed the program, and all parents found the newsletters to be useful. Almost all parents (15/16, 94%) agreed that the DELISH program would be useful to other parents.

Conclusions

The improvement in salt-related KABs in the DELISH program indicates the potential for online technology, to disseminate simple salt reduction education messages to families with primary school–aged children. Future work should seek to improve the quality of data collected by including a larger sample size and a control group to integrate the program within the school setting to enable wider dissemination.

The Science of Salt: A focused review on salt-related knowledge, attitudes and behaviors, and gender differences

The aim of the current review was to examine the scope of studies published in the Science of Salt Weekly that contained a measure of self-reported knowledge, attitudes, and behavior (KAB) concerning salt. Specific objectives were to examine how KAB measures are used to evaluate salt reduction intervention studies, the questionnaires used, and whether any gender differences exist in self-reported KAB. Studies were reviewed from the commencement of Science of Salt Weekly, June 2013 to the end of August 2017. Seventy-five studies had relevant measures of KAB and were included in this review, 13 of these were salt-reduction intervention-evaluation studies, with the remainder (62) being descriptive KAB studies. The KAB questionnaires used were specific to the populations studied, without evidence of a best practice measure. 40% of studies used KAB alone as the primary outcome measure; the remaining studies used more quantitative measures of salt intake such as 24-hour urine. Only half of the descriptive studies showed KAB outcomes disaggregated by gender, and of those, 73% showed women had more favorable KAB related to salt. None of the salt intervention-evaluation studies showed disaggregated KAB data. Therefore, it is likely important that evaluation studies disaggregate, and are appropriately powered to disaggregate all outcomes by gender to address potential disparities.

"I rarely read the label": Factors that Influence Thai Consumer Responses to Nutrition Labels

BACKGROUND

This qualitative study employed the Knowledge-Attitude-Behaviour (KAB) model and Health Belief Model (HBM) to investigate factors influencing Thai consumer decision making about use of nutrition labels. Labels include both Nutrition Information Panels (1998-) and Guideline Daily Amounts labels (2011-).

METHOD

In-depth interviews were conducted with 34 participants representing two socio-demographic extremes in Thailand--"urban Bangkok" (university educated consumers) and "provincial Ranong" (non-university educated consumers). An integrated KAB-HBM model was used to devise in-depth interviews for a qualitative study using 20 open-ended questions and samples of food package labels. Additional questions arose from the interviews and they lasted 30-45 minutes and were video recorded. The analysis identified recurring themes using Atlas.ti software.

RESULTS

Most participants (n=25) were aware of nutrition labels but a much smaller number (n=10) used and derived any benefit from them. Nutrition label users were classified into 4 groups: A) competent user; B) confused user; C) aware non-user; D) unaware non-user. Better educated participants were better at understanding nutrition labels but not more likely to use labels. Belief that nutrition influences health increased likelihood of using nutrition labels to make decisions about food. Being well-educated and motivated by health concerns increased likelihood of attention to nutrition labels.

CONCLUSION

Results are discussed with a view to increasing the use of nutrition labels by Thai consumers. Our findings, drawing on a combination of the KAB and HBM models, can contribute to strategies motivating consumers to use nutrition labels and can provide useful insights for developing promotional strategies.

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.

Sodium content and labelling of processed and ultra-processed food products marketed in Brazil

OBJECTIVE

To analyse the Na content and labelling of processed and ultra-processed food products marketed in Brazil.

DESIGN

Cross-sectional study.

SETTING

A large supermarket in Florianopolis, southern Brazil.

SUBJECTS

Ingredient lists and Na information on nutrition labels of all processed and ultra-processed pre-prepared meals and prepared ingredients, used in lunch or dinner, available for sale in the supermarket.

RESULTS

The study analysed 1416 products, distributed into seven groups and forty-one subgroups. Five products did not have Na information. Most products (58.8 %; 95 % CI 55.4, 62.2 %) had high Na content (>600 mg/100 g). In 78.0 % of the subgroups, variation in Na content was at least twofold between similar products with high and low Na levels, reaching 634-fold difference in the 'garnishes and others' subgroup. More than half of the products (52.0 %; 95 % CI 48.2, 55.6 %) had at least one Na-containing food additive. There was no relationship between the appearance of salt on the ingredients list (first to third position on the list) and a product's Na content (high, medium or low; P=0.08).

CONCLUSIONS

Most food products had high Na content, with great variation between similar products, which presents new evidence for reformulation opportunities. There were inconsistencies in Na labelling, such as lack of nutritional information and incomplete ingredient descriptions. The position of salt on the ingredients list did not facilitate the identification of high-Na foods. We therefore recommend a reduction in Na in these products and a review of Brazilian legislation.

Sodium intake and blood pressure in children

Elevation of blood pressure (BP) and the risk for progression to hypertension (HTN) is of increasing concern in children and adolescents. Indeed, it is increasingly recognized that target organ injury may begin with even low levels of BP elevation. Sodium intake has long been recognized as a modifiable risk factor for HTN. While it seems clear that sodium impacts BP in children, its effects may be enhanced by other factors including obesity and increasing age. Evidence from animal and human studies indicates that sodium may have adverse consequences on the cardiovascular system independent of HTN. Thus, moderation of sodium intake over a lifetime may reduce risk for cardiovascular morbidity in adulthood. An appetite for salt is acquired, and intake beyond our need is almost universal. Considering that eating habits in childhood have been shown to track into adulthood, modest sodium intake should be advocated as part of a healthy lifestyle.