Efforts to Consume Less Salt: A Public Health Success in the Making

The 2015–2020 US Dietary Guidelines reaffirm the need for Americans to reduce their sodium intake to prevent and control hypertension and related cardiovascular, cerebrovascular, and renal diseases. In the United States and the many other countries where eating patterns rely heavily on manufactured and restaurant foods, the primary strategy for reducing sodium intake focuses on food industry measures. The goal is to enable greater consumer discretion in salt consumption and facilitate lower intake by reducing sodium in the wide array of products that cumulatively result in excess intake.¹ Consumer information and education approaches are important to the overall strategy but cannot be effective alone in the current food environment.

THE NATIONAL SALT REDUCTION INITIATIVE

This issue of AJPH includes a very timely progress report from the National Salt Reduction Initiative (NSRI).² The NSRI was a vanguard effort, initiated in 2008 by the New York City Department of Health and Mental Hygiene, to engage the food and restaurant industry in voluntary efforts to decrease the amount of sodium in their products. The report, which focuses on progress in the packaged foods segment of the market, is especially timely in light of the Food and Drug Administration (FDA) release, in June 2016, of draft guidance for public comment on food industry targets for sodium reduction. This signals a step forward in the federal government’s willingness to exercise leadership in this arena. Curtis et al.² note that such federal leadership has been a long time in coming. Concerns about high sodium intake have been a prominent part of dietary guidance since the 1980s. A 2010 Institute of Medicine report called for the FDA to “expeditiously initiate a process to set mandatory national standards for sodium content of foods.”^1(p10) In 2015, the Center for Science in the Public Interest, a nutrition advocacy organization, sued the FDA for failure to regulate salt in the food supply.³

DIRECT ENGAGEMENT WITH THE FOOD INDUSTRY

The NSRI, a coalition involving more than 100 national health organizations and state and local agencies, constitutes an extensive nonfederal effort to make progress on sodium reduction through direct engagement with the food industry. Foundational NSRI activities included the development of an elaborate framework for establishing targeted levels of food sodium content (i.e., maximum levels and averages) appropriate to different products and product categories. The process included the creation of a packaged foods database with nutrition information for product categories responsible for 80% of packaged food sales. This database enabled the NSRI to track sodium content from initial levels against targets for gradual reductions over the five-year period from 2009 to 2014. The authors of the progress report concluded that progress in meeting targets, although evident, was suboptimal. However, they also emphasized the apparent feasibility of this target setting and monitoring approach as important to the infrastructure for eventual success.

THE GLOBAL CONVERGENCE

These developments hold promise both from a US perspective and when viewed as part of the worldwide movement to reduce sodium in foods.⁴ Packaged food production and marketing are global in nature. Actions on sodium in foods taken in different countries can be mutually reinforcing in fostering changes in industry norms and behavior. Furthermore, reports of wide variations in the sodium content of the same products as sold in different countries suggest that there is room for learning from current industry practices about safe and effective ways to achieve sodium reduction targets.⁴

Despite continuing debate in the scientific community about the lowest level of population sodium intake to target,⁵ the global convergence around efforts to reduce dietary sodium intake to about two grams per day is striking. Evidence of some type of action by national governments has been reported for more than 70 countries,⁶ with more than half setting targets, and most focusing on multiple types of food rather than single sources such as breads. World Health Organization (WHO) guidance on strategies for reducing salt intake was reported from a 2006 forum on reducing salt intake in populations. The 2011 UN General Assembly resolution endorsed salt reduction as among the most cost effective approaches available for combating the global epidemic of noncommunicable diseases, giving the WHO salt reduction initiatives even greater import.

Almost all of the national approaches reported to date rely on guidance and voluntary approaches rather than mandatory targets.⁷ Whether this continues may depend on how much progress is made. Curtis et al. point out that the NSRI effort was motivated in part by the apparent success of the UK experience with voluntary sodium reduction by the food industry.² The use of voluntary strategies could reflect an appreciation, by both health advocates and policymakers, for the potential complexities involved in product reformulation and for the possibility that allowing companies some room for flexibility could lead to better overall results. Underlying the NSRI and similar target setting approaches is a principle of gradual and nuanced rather than drastic and sudden changes in the sodium content of foods. If applied across the spectrum of packaged foods, this approach should allow consumers to recalibrate their salt preferences downward. Consistent with this reasoning, the emerging FDA guidance includes both short- (two-year) and long-term (10-year) targets.

MONITORING PROGRESS

As with any population-wide intervention on a universal and fundamental behavior such as food consumption, future actions should rely to the greatest extent possible on sound evidence generated from numerous perspectives, with ample consideration of the potential for adverse unintended human or social (including economic) consequences. Research to inform product reformulation is the food technology domain, but public health estimates of impacts on morbidity reductions, associated health care costs, and lives saved under various scenarios must continue. Well-reasoned and executed studies can refine our ability to convince both public and private sector decision-makers of why it is important to take sodium reduction initiatives to scale. These studies are needed in a variety of population contexts, including developing countries where processed foods are less likely to be the dominant sodium sources or where cultural practices include very high sodium intakes. Intricate tracking of implementation progress with respect to food sodium content, and linking observed changes to effects on dietary patterns, as illustrated by the NSRI report in this issue,² will be critical. Monitoring of progress on sodium must also consider overall dietary adequacy and quality and food safety in the contexts of developmental or life stage, cultural influences, socioeconomic status, and health profiles.

The basis for the convergence around the need for food supply sodium reduction stems from the widespread consensus that this, as a core strategy, will have commensurate effects in lowering population dietary sodium intake. This, in turn, is expected to have a huge impact in reducing the prevalence of hypertension and related disease risks. This approach will only work if enough companies change enough products to achieve tipping points in shifting consumer preferences, and sustain these changes. Successful efforts will presumably be facilitated by complementary consumer awareness and education programs and food labeling strategies.

Clearly much more needs to be done from a public health perspective—a combination of advocacy, health diplomacy, and vigilance—to achieve targets and to make sure that their achievement yields results that are favorable from all perspectives. That said, an optimistic view of the message of the NSRI report given what is happening in the US federal government and globally is that a historic public health success is in the making.