Setting sodium targets for pre-packaged foods in China — an exploratory study

Abstract

Introduction:

Setting sodium targets for pre-packaged food has been a priority strategy for reducing population sodium intake. This study aims to explore the attitudes and considerations of researchers and key stakeholders toward implementing such policy in China.

Methods:

An exploratory study comprising a survey and a focus group discussion was conducted among 27 purposively selected participants including 12 researchers, 5 consumers, 4 administrators, 3 industry association representatives and 3 food producers. The survey/discussion covered the key questions considered when developing/promoting sodium targets. Free-text responses were manually classified and summarized using thematic analysis.

Results:

Two-thirds of the participants supported target-setting policy. Researchers and administrators were most supportive, and food producers and associations were least supportive. Adapted WHO food categorization framework was well accepted to underpin target-setting to ensure international comparability and applicability for Chinese products. Maximum values were the most agreed target type. The WHO benchmarks were thought to be too ambitious to be feasible given the current food supply in China but can be regarded as long-term goals. Initially, a reduction of sodium content by 20% was mostly accepted to guide the development of maximum targets. Other recommendations included implementing a comprehensive strategy, strengthening research, engaging social resources, establishing a systematic monitoring/incentive system, maintaining a fair competitive environment, and developing a supportive information system. Target-setting policy was acceptable by most stakeholders and should be implemented alongside strategies to reduce discretionary salt use.

Discussion:

Our findings provide detailed guidance for the Chinese government when developing a target-setting strategy. The methods and results of this study also provide meaningful references for other countries to set sodium targets for pre-packaged foods and implement other salt reduction strategies simultaneously.

Introduction

Salt/sodium reduction is recognized as one of the most cost-effective interventions to reduce the burden of chronic noncommunicable diseases. As highlighted in the WHO SHAKE package, population-wide salt reduction requires comprehensive strategies (1). A key strategy is harnessing the food industry to use less salt through food reformulation. Establishing sodium targets or target-setting has been identified as a priority strategy to promote food reformulation due to its scalability and sustainability and large potential benefit (2). Per the recent WHO global report on sodium intake reduction, however, only 65 countries around the world have implemented this policy (3).

To accelerate progress, the WHO established global sodium benchmarks for 11 categories and 58 subcategories of foods in 2021 to support countries to introduce national target-setting policies. The benchmarks should be achievable goals because they have been determined as the lowest maximum value of existing national or regional targets for each subcategory (4). However, gradually reduced sodium targets are acceptable for most countries especially for those where the pre-packaged foods have relatively high baseline sodium concentrations and the dietary sodium is mainly from cooking/table salt.

China is among the countries with the highest population salt intake, with the estimated salt intake for adults at around 11 g/d in 2020 (5). Over 80% of sodium intake comes from salt and condiments added during cooking rather than from pre-packaged food (6, 7). To achieve the national goal of 20% reduction in salt intake by 2030 (8), China has launched several national programs to reduce the discretionary salt use through mass media campaigns and environment development (9–13). Regarding salt reduction through pre-packaged foods, except for mandatory labeling of sodium (14), no target-setting policy has been released by the government. This is despite the fact that the consumption of pre-packaged foods in China is increasing (15, 16), and most pre-packaged foods contain more sodium than their counterparts in other countries (17–19). Till now, only a set of voluntary sodium targets has been included in the Guideline for Salt Reduction for Chinese Food Industry issued by a research group in 2019 (20).

Around the world, there has been substantial experience in developing and implementing sodium targets for different foods. However, the development and implementation of sodium targets are complex, and each country needs to consider their own conditions when determining the leading institutes or organizations, type of targets (maximum or mean), approaches used to develop/update the targets, priority foods, type of implementation (voluntary or mandatory), and systematic monitoring and evaluation.

To drive progress on sodium reduction in pre-packaged foods in China, two studies were undertaken in parallel: (1) a quantitative study modeling the effect of different sodium target designs on sodium reduction to support the selection of the initial targets by government (21), and (2) the current exploratory study (mainly based on qualitative interview) to find out the opinions and suggestions on how to initiate such strategy by interviewing experienced researchers, policy-makers, delegates of relevant social organizations, and influential representatives from companies and consumers in China.

For specific, the purpose of the exploratory study is to explore (1) general attitudes toward a target-setting policy, (2) attitudes toward adopting the WHO benchmarks, (3) key parameters for initiation, and (4) opportunities and challenges\barriers to be addressed when starting a target-setting policy in China.

Methods

Study context

The National Institute for Nutrition and Health (NINH) and The George Institute for Global Health (TGI) China co-led the work based on their collaboration in the Action on Salt China (ASC) program (22). A working group was established in June 2021 to explore how to leverage existing evidence and the WHO benchmarks to facilitate the Chinese government setting sodium targets for pre-packaged foods. Several virtual technical consultation meetings were convened from July to December 2021 to refine the study design. An expert committee, composed of 5 national nutrition experts from NINH, TGI, WHO China office, Chinese Nutrition Society and Peking University, was also established to review the protocols and help nominate the participants. All the consultants and experts have direct experience in setting sodium targets or understanding of the technological aspects of sodium use and sodium reduction.

Participants and recruitment

Thirty potential participants were nominated by the expert committee. They came from governments, research organizations, social organizations, food enterprises and consumers, and had recognized expertise and significant influence in changing food supply through policymaking/administration, research, management, reformulation/development, and purchasing/consumption. Consumer representatives mainly came from fields such as media, advertising, and marketing, mainly considering their representativeness and influence on public opinion. All participants were contacted via email and 27 of them agreed to participate.

Data collection

The is a mixed method study, consisted of a structured individual survey and a focus group discussion. It was conducted from January to March 2022. Both the survey and group discussion were guided with the same tool (Appendix S1: Guide and questionnaire for the survey and group discussion) which covered the key questions considered by countries and the WHO when developing and promoting sodium targets/benchmarks. It contained 13 questions, of which the first 10 questions were single/multiple-choice questions accompanied by open areas to collect additional opinions on certain topics. The last 3 questions were open-ended.

The individual survey was delivered through Questionnaire Star,¹ a widely used electronic survey platform. People could use their computers or mobile phones to complete the survey. To enable the participants to make informative choices and comments, a 1.5-h systematic background introduction was given in advance which covered the global experience of target-setting for salt reduction, the WHO global sodium benchmarks for different food categories, the key findings of the parallel quantitative study, and the current strategies for salt reduction in China. The individual survey was guided by an experienced investigator, and the participants were encouraged to enter their answers and opinions directly into the electronic questionnaire platform without discussion with others.

Two focus group discussions were convened after the individual survey: onsite group and online group. The online group was organized for those unable to attend the face-to-face discussion due to COVID-19. All the participants were encouraged to express their opinions and suggestions which were recorded in the open text areas of the outline which had been printed out in advance for each participant. Near the end of the group discussion, all the participants were told the main findings of the individual survey with the purpose of helping the participants further refine their thoughts. The same investigator moderated the whole process following the guide and structured questionnaire.

Data analysis

Participants were characterized according to their role and organization. Responses to the closed survey questions were entered into Excel (Microsoft 365 Apps for enterprise), analyzed and summarized. The free-text responses for each question were manually classified and summarized by the core research team following Braun and Clarke’s method of thematic analysis (23). This includes becoming familiarized with the data, developing initial codes, collating these codes to identify emerging themes, and then ensuring these themes connect to the data by creating a thematic map. The responses to the last question “13. Are there any other considerations?” were all re-allocated into the other 12 questions because no new theme was found. When reporting the results, the questions were re-organized to fit the four study objectives.

Results

All 27 participants completed the survey and focus group discussion. Of these, 8 participated online group discussion due to COVID-19. By role, there were 12 researchers from nutrition or food fields (5 from national institutes, 3 from universities, 3 from international institutes, and 1 from a private institute), 5 consumers (2 with education background in health and 3 without), 4 administrators (1 from government, 3 from government agencies), 3 senior delegates from professional associations (food industry, condiments, and meat), and 3 representatives of food producers (2 international and 1 local) (Table 1).

Responses to the first 10 questions with closed choices are presented in Table 2. The major findings from the open-ended questions are summarized in Tables 3, 4, including illustrative quotes organized according to the four research objectives.

General attitudes toward the target-setting policy

In general, two-thirds (18/27) of the participants supported implementing the policy as soon as possible because pre-packaged foods in China usually contain too much sodium and sales are increasing year by year. The other one-third disagreed and thought the contribution of pre-packaged foods to sodium intake was low and that implementing such a policy was not cost-effective (Q1). Differences between stakeholder groups were clear: most supporters were researchers (11/12) and administrators (4/4), and most opponents were food producers (3/3) and association representatives (3/3; Table 2).

Participants in support of a target-setting policy also stated that sodium reduction has been emphasized in national health strategy, consumption of pre-packaged foods among the younger generation is increasing, and the policy will drive food industry innovation and consumer awareness. Meanwhile, those opposed emphasized the importance of consumer awareness and had concerns about impacts on the supply chain and sales, and availability and variety of products (Table 3).

More than half of the participants (15/27), including food producers and those from associations thought enterprises may actively cooperate if they find the sodium contents of some products are too high and might be doing harm to sales, whereas only one participant responded that they did not think enterprises would cooperate and 11 others thought it would be determined by consumer acceptance, government attitude and enterprises’ capacity (Q2; Tables 2, 3).

Attitudes toward adopting the WHO sodium benchmarks

Nearly all participants (25/27) agreed that the WHO benchmarks and the underpinned food categorization framework should be referred to, but adjustments are needed to fit China’s context. The representative view was that the benchmarks could be taken as long-term goals but would be too ambitious for initial use. To be feasible, the targets should be set step by step based on China’s national conditions including the baseline sodium contents and contribution of individual food categories to sodium intake. (Q3) The majority of participants (18/27) were in favor of choosing a percentile sodium content such as the 75th percentile (Q5) and using an adapted WHO food categorization framework (17/27) to ensure international comparability and applicability for Chinese food products (Q7; Tables 2, 3).

Key parameters for target-setting

Type of targets: Most preferred only setting maximum sodium targets (13/27) or setting both maximum and mean targets (11/27), although one food producer insisted that the most important thing is to publicize and educate consumers. (Q4) When a mean target was suggested, nearly all respondents (20/21) suggested sales data and market share should be considered (Q6; Table 2).

Priority foods: Regarding implementing the policy, most (20/27) participants preferred setting targets first for the major dietary sodium contributors (Q8; Table 2).

Voluntary or mandatory: A few participants insisted that only mandatory implementation would be effective, but most (23/27) supported voluntary approach. The potential negative impact on enterprise development, lack of readiness for systematic monitoring and evaluation, and gradually transitioning from voluntary to compulsory were the major considerations and suggestions (Q9; Table 2).

Timeline: More than half of the participants (15/27) preferred a timeline consistent with the national goal of “reducing salt intake by 20% by 2030.” However, most association representatives and food producers were more conservative, suggesting that because pre-packaged foods are not the main source of sodium intake, sodium reduction in pre-packaged foods only needs to keep up with the decline in discretionary salt use. Meanwhile, some researchers and administrators suggested that the timeline should be more aggressive considering that China’s target-setting policy has fallen behind and is likely to be implemented on a voluntary basis (Q10; Table 2).

Opportunities and challenges/barriers to be addressed

In the focus group, opportunities and challenges were more broadly discussed regarding policy, social resources, technical aspects, publicity, and education and training to inform the development of the policy (Q11 and Q12; Table 4).

Most participants believed that the Chinese government is powerful and the policy environment supporting salt reduction has been established. To improve the target-setting policy, the most commonly mentioned challenges/barriers to be addressed were: (1) implementing a comprehensive salt reduction strategy to improve awareness and reduce discretionary salt use simultaneously; (2) strengthening research to clarify the impact of target-setting and provide support to the food industry and stakeholders; (3) engaging social resources in research, education, training and coordination; (4) establishing a performance appraisal and incentive system; (5) maintaining a fair competitive environment; and (6) developing a supportive information system (Table 4).

Most participants suggested that the government should clarify the responsibilities of food associations and societies in leading and supporting their member enterprises in food reformulation. Several key issues were mentioned as needing technical solutions: whether/how to reformulate high-sodium condiments (when less salt added, consumers tend to use/eat more), how to avoid secondary hazards from newly added additives, and how to engage small and medium-sized enterprises. Current publicity activities were regarded as ineffective in encouraging consumers to choose lower-sodium products. It was strongly suggested that legislation would be needed to obtain the support of publicity departments outside the health sector. To improve education and training, it was suggested to empower various relevant associations and educational institutions, and actively seek the support of the education sector to improve the coverage of training and education in a short time (Table 4).

Discussion

This exploratory study explored the views of key stakeholders on whether and how to reduce sodium in pre-packaged foods through target-setting policy in China, including how to adopt or adapt the WHO global sodium benchmarks. Overall, we found that most participants supported setting sodium targets for pre-packaged foods, with maximum targets set at an agreed percentile based on the current levels of sodium in China’s food supply, and the food categories following the WHO food categorization framework with necessary food supply adaptions. This study findings indicate that setting sodium targets is an important strategy to reduce sodium intake in China. However, there is also a need for strong government leadership and robust monitoring to guarantee the achievement of 20% reduction of sodium content in pre-packaged food by 2030.

Leveraging the WHO benchmarks

As adopted by the WHO benchmarks, setting maximum sodium targets were supported by most participants because maximum values are the most straightforward concept for governments, consumers and the food industry (24), and allow easy monitoring of foods and companies (25).

Our quantitative study, conducted in parallel with the current study, which modeled the potential impact of the WHO benchmarks alongside other possible targets, revealed the WHO benchmarks would achieve around 50% reduction but were considered too ambitious for initial use. Instead, a set of targets that could lead to a 20% reduction in sodium content from the baseline was preferred (21). This may be a reasonable starting point considering 20% sodium reduction is substantial and may not be noticed by consumers and should be acceptable by most companies (26, 27).

The recent WHO global report on sodium intake reduction noted that 65 of the 194 Member States have implemented a target-setting policy using mandatory (n = 21), mandatory and voluntary (n = 6), or voluntary (n = 38) approaches (3). Mandatory reformulation generally achieves a larger effect than voluntary implementation. Without close government oversight, voluntary targets are not sufficient incentives for the food industry to reformulate; hence, close monitoring and the potential for mandatory targets will be required to ensure the voluntary program has an effect (24). In any case, monitoring of adherence to targets needs to be transparent and independently verified.

Support across sectors for target setting

While two-thirds of participants supported immediate target setting, there were differences between stakeholder groups. Neither food producers nor representatives of food associations opposed the government’s policy and the public interests on sodium reduction, but they are apparently not ready to support the target-setting policy. As seen in other countries, when considering how to implement such policy, the food industry tends to resist and raise difficulties or challenges (28, 29), neglecting that the existing sodium targets/benchmarks are the evidence that reducing salt/sodium in the food supply is feasible for the food industry and acceptable to consumers (24). Strengthening education, research, training, exchange and technical support, clarifying responsibilities of associations, and promoting legislations for enterprises would be among the most effective solutions. Evidence indicates that sodium reduction by 20–30% for all products is acceptable for most companies (26, 27).

Combination with other sodium reduction strategies

In China, discretionary salt use dominates the population sodium intake (6, 7). Comprehensive strategies to engage media, families, and catering and food industries must be considered in parallel. To do so, national systematic sodium reduction strategies and promotion mechanisms are needed to ensure multispectral synchronous implementation in a targeted and planned manner. Of course, there are several other options that can complement food reformulation that are not covered in this study, including sales and marketing regulation, improvement of food labeling and taxation of high-sodium foods. WHO is in process of developing guidelines on the use of low-sodium salt substitutes (30), which should be referred to when considering their use.

Limitations

The study was designed as a very structured and focused survey and discussion, which improved the efficiency of this study but may also have restricted the thoughts of the participants. In addition, the participants were purposively selected and no representatives from other relevant government sectors like education and market supervision were invited. Further extensive interviews, covering researchers and decision-makers from relevant non-health sectors, are meaningful for the formulation and implementation of a target-setting policy for salt reduction.

Conclusion

Setting sodium targets for different pre-packaged foods was supported by most stakeholders and should be implemented alongside strategies to reduce discretionary salt use during cooking and eating. This study provides information on perspectives, considerations, opportunities, and challenges for a target-setting policy that could be effective in China.

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