1. Introduction
Excess dietary salt causes high blood pressure [
1], one of the most important risk factors for cardiovascular disease (CVD) [
2]. Average adult salt intake in Australia has been estimated to be 9 g/day (~3500 mg sodium/day) [
3,
4], which is more than double the Australian government’s Suggested Dietary Target of 4 g/day [
5]. The high level of salt intake of Australians has been estimated to cause 11% of deaths attributable to ischemic heart disease and 15% of deaths caused by stroke [
6]. Thus, cost-effective policy approaches that can reduce population salt intake are urgently needed [
7,
8,
9,
10,
11].
Similar to other developed countries, three-quarters of dietary salt for the Australian population comes from processed and packaged foods, rather than discretionary sources (salt added during cooking or at the table) [
12]. Bread, processed meats and breakfast cereals are some of the largest contributors to salt intake in Australia, together accounting for about 20% of daily intake [
13]. A systematic effort to reformulate food products to reduce their salt content is therefore a promising strategy for lowering the Australian population salt intake [
9]. The United Kingdom (UK.) is considered a leader in salt reduction strategies [
14], and their government-led national salt reduction program has successfully lowered population salt intake by about 15% over the last seven years to have the lowest known salt intake of any developed country [
15,
16]. A central pillar of the UK. policy platform is a voluntary salt reduction program that encourages food product reformulation by manufacturers to meet specific targets that are progressively lowered over time [
16]. In an effort to similarly lower the salt content of processed foods in Australia, the ‘Food and Health Dialogue’ (FHD) program was launched by the Federal Government in 2009. Through a series of roundtables convened to engage key stakeholders, voluntary salt reduction targets for each of 10 food product categories and a timeline for achieving these proposed changes were established [
17].
The effect of the FHD on the salt content of the food supply has so far not been quantified. A detailed evaluation of changes in the salt content in specific food categories is needed to determine the success or failure of the FHD program and to guide future policy directions [
16]. The sodium reduction targets for three FHD food categories (breads, ready-to-eat breakfast cereals and processed meats) were scheduled to be achieved in December, 2013, and the aim of the present study was to assess whether these targets have been met, to quantify the magnitude of any changes in sodium content and to explore whether changes differed by manufacturer or product category. We also examined changes in product sodium content according to a manufacturer’s publicly-stated commitment to the FHD program.
4. Discussion
These data provide the first objective evaluation of the changes in sodium content of bread, breakfast cereals and processed meats in Australia following the establishment of the FHD. Our results show that while excellent progress has been made by some food companies, overall voluntary reductions have not yet reached optimal levels. This is particularly so for processed meats, for which less than half of the products surveyed met the FHD 2013 targets. Our findings also identify substantial differences between the rates of product reformulation achieved by different food companies and argue for a more robust intervention strategy that is able to effectively engage with a larger proportion of the sector targeted.
Argentina and South Africa have introduced legislation regulating the maximum level of sodium that foods can contain [
21], but the majority of countries with salt reduction targets have opted for a voluntary approach, as legislative processes are complicated and require considerable time to implement. The last decade in the UK. shows that a successful public private partnership (PPP) between government, industry and public health groups employing a multi-component strategy can lower population salt intake [
16,
22]. Setting sodium reduction targets and encouraging the food industry to gradually reformulate their products have been key elements of the UK. approach, which was initiated by the Food Standards Agency in 2003 and subsequently taken on by the Public Health Responsibility Deal for England in 2011. Progressively more challenging sodium reduction targets for over 60 food types have been set and, coupled with consumer campaigns and a threat of regulation, have achieved the most comprehensive ever falls in the sodium content of processed foods in a developed country, with reductions of up to 70% in some food categories reported [
16,
23,
24,
25]. The extent to which these methods can be transferred to other countries with different political and economic influences and consumer preferences has remained largely unknown. Our examination of the FHD program in Australia, which was based closely on the UK. approach, therefore provides novel evidence affirming the potential for a PPP target-based strategy to lower sodium content in other settings. The sodium reduction targets set by the FHD are closely aligned with the UK. targets for these three food categories.
Despite the progress made, our results also highlight areas of concern. The FHD participants negotiated, agreed and committed to take action on a series of modest, time-bound targets, but there was only partial voluntary compliance by the 2013 deadline for the first three categories identified. The wide range of sodium content observed in each of the food categories in 2013, including many products with sodium levels substantially below the FHD target, suggests technical capability is unlikely to be the major issue hindering compliance with the FHD targets. FHD participants did report technical and resource constraints hampering their efforts to reduce sodium in processed meats in November, 2012, but minutes from an FHD Executive Meeting in May, 2013, state that participants were nonetheless on track to meet targets in nominated products for December, 2013 [
26]. The reason why there was a subsequent failure to voluntarily comply is therefore likely to be, in part at least, due to other shortcomings of the FHD program, such as the lack of monitoring and the absence of media publicity and public awareness of food company actions [
16,
27].
The marked difference in progress made by George Weston and Primo Smallgoods, two market leaders producing processed meats, is indicative of the problems that can arise with a weak PPP [
28]. More products from George Weston met the target in 2013 compared to 2010, but the opposite was true for Primo Smallgoods. Heterogeneity in food reformulation efforts between manufacturers has also been reported in prior studies of sodium reduction [
23,
24,
29,
30,
31], as well as for dietary fats [
32]. It is beyond the scope of this study to assess what, and how, company characteristics influence action, but this is clearly an important area for future research given the central role that food reformulation will play in the prevention of diet-related ill health. Our observation of decreased sodium content in the products of both FHD participants and non-participants is encouraging and suggests that engagement with the major food manufacturers and grocery retailers may produce flow-on effects in companies other than those directly engaged.
The sodium in food is essential for the taste characteristics of many products and plays other functional roles in manufacture and storage. For example, in bread, sodium controls yeast activity and aids in processing; in breakfast cereals, it enhances texture, and in some processed meats, it acts as a preservative by preventing the growth of microorganisms and, thus, increasing shelf life [
33,
34]. Efforts to reduce sodium content will therefore be facilitated by technological innovation; although this is a more pressing requirement for some food categories than others, better and more widespread application of existing technology still appears to present a significant opportunity [
33].
Excess dietary salt drives the rise in blood pressure with age, and population-wide salt reduction has been identified as a priority public health goal for the next decade by the World Health Organization in its efforts to avert chronic disease [
35]. Breads, breakfast cereals and processed meats were prioritised for sodium reduction by the FHD, as they are frequently consumed by a large portion of the Australian population [
17]. The 2011–2012 National Nutrition and Physical Activity Survey found that in the 24 h prior to interviewing, two thirds of Australians had eaten two slices of regular bread, more than a third had eaten breakfast cereals and almost a quarter had consumed processed meats [
13]. Together, these three food categories were estimated to be responsible for about one fifth of daily salt intake in adults, making them a good initial target for salt reduction efforts [
13]. However, if effects comparable to those in the UK. are to be achieved [
22], there will need to be an expansion of the FHD program to cover additional food categories, further lowering of the existing category targets and new efforts to encourage better industry voluntary compliance. Given that mean salt intake among Australians is currently some two-fold higher than the upper level suggested [
3,
5,
36], learning the lessons of the UK. program should be a priority [
25].
A key strength of our study is the consistent and repeated sampling method used to obtain sodium data on a comprehensive range of breads, breakfast cereals and processed meat products from grocery retailers in Australia, who together have about 95% of the market share of packaged groceries [
37]. Data tracking over sequential years allowed for an assessment of the reformulation of foods that were available in multiple years, as well as an examination of the sodium level of new products launched each year. Results were similar for all products and for products that were available in multiple years, which suggest progress towards FHD targets were met via both reformulation, as well as the introduction of new lower sodium options. Whereas prior monitoring studies generally focused on single food categories [
24,
30,
31], we expanded our analyses to include multiple product categories that are major contributors of dietary sodium in Australia and highlighted the substantially different progress made for each category. Finally, we carefully tracked products from individual food companies and retailers to contrast and compare their efforts.
Our study also had several weaknesses. Coverage of foods in the categories we studied is unlikely to be complete. Due to the small number of emulsified luncheon meat products identified in all years, there was a high level of uncertainty in these results. Therefore, our findings should be interpreted with caution. We were unable to include breads from in-store bakeries or processed meats from in-store delicatessens, as these products do not carry a NIP from which to collect data and are therefore excluded. Nonetheless, data collection included private label and branded products and is likely to be broadly representative of packaged foods available for sale in Australian supermarkets. We were unable to assess all of the food companies involved in the FHD [
17], as the products of some do not appear to be sold directly to the consumer through the supermarkets we sampled (e.g., they supply ingredients for food service). The integrity of our nutritional data also depends on the accuracy of the NIP and relies on food companies to update the NIP as products are reformulated. Prior studies suggest that NIP data in Australia is generally accurate and reliable [
38].
