The U.S. Food and Drug Administration (FDA) issued a voluntary salt (sodium chloride) reduction recommendation for commercially processed, prepared, and packaged food on October 13th, 2021 [1]. The guidance is intended to be voluntary and short-term (~2.5 years) in duration. The guidelines are important because most salt consumption comes from processed food and packaged food [7, 8]. Salt is added during food manufacturing as a preservative to protect food from microbes and to enhance taste.
The Dietary Guidelines for Americans in 2015 and 2020 and the Chronic Disease Risk Reduction (CDRR) Intake for Sodium call for limiting sodium intake to 2300 mg/day (2.3 gram/day), equivalent to 1 teaspoon of salt for individuals age 14 or older. However, the average sodium intake in the US is 3393 mg/day (3.4 grams/day) [2]. Therefore, the new FDA recommendation’s call for voluntary gradual sodium reduction in prepared and processed food to reduce the US population sodium intake by 12%, to 3 grams in 2.5 years, is a welcomed initiative for a healthier diet and for decreasing the burden of chronic diseases that disproportionately affect racial and ethnic minorities.
Why is sodium reduction important? Sodium is an essential nutrient and electrolyte. It is the most abundant extracellular cation in the body and is required for numerous physiological functions. It is tightly regulated with several biochemical processes to maintain blood sodium in the normal range. However, excess sodium intake leads to more water retention, which could increase blood volume, and increase the work of the heart to pump the additional load. A large body of literature has documented that excess sodium intake could contribute to the development of hypertension and increased cardiovascular disease risk [9, 10]. Reducing salt intake may reduce blood pressure (systolic and diastolic) in people with normal blood pressure and patients with hypertension [11-14]. Meta-analysis studies showed a beneficial dose-response effect of salt reduction on hypertension [12]. Although scientific evidence shows that salt reduction decreases the risk of hypertension and stroke, failure to follow recommendations due to misinformation and confusion regarding the salt content in processed and packaged food, and the impact of high salt on blood pressure and heart disease still exists [15]. Providing accurate information about sodium content will allow people to make informed decisions about their salt intake and afford more food choices and a diverse, healthy diet.
To be successful, a multipronged approach to decrease salt intake would be practical and effective. Such an approach includes decreasing the amount of added salt in processed food, clear labeling of packaged food, nutrition education, and using salt alternatives and substitutes like herbs and spices to provide flavor. People may not realize how much salt is in processed food and thus may underestimate the amount of sodium they consume daily. For example, a half-cup serving of Campbell’s vegetarian vegetable soup contains 650 mg. of sodium, 28% of the recommended daily amount.
The recent FDA guidelines were preceded by efforts to reduce sodium led by the New York City Department of Health and Mental Hygiene, which initiated a National Salt Reduction Initiative (NSRI) in 2009 [3]. Several food manufacturers, foodservice operations, and chain restaurants responded to the NSRI initiative and have taken steps to reduce the salt content in processed food and provide low-sodium alternatives, but more efforts are needed at the population level [4-6]. Gradually decreasing salt intake in incremental steps will allow taste buds to adapt to the decreased intake, enable consumers to adjust their taste preferences, and increase the palatability of less salty food. A voluntary sodium reduction, rather than a mandate, will appeal to food service establishments, restaurants, and the food industry and allow a time window to reduce the salt content in the food supply, reformulate processed and packaged food while maintaining food safety, develop new, healthier products, and avoid unintended consequences from salt-reduction, such as replacement with sugar or saturated fat.
As the food industry voluntarily decreases the salt content gradually and offers low-salt varieties, individuals could do their part to complement these efforts. For example, salt-reduction approaches include decreasing salt addition from the saltshaker, using herbs, spices, and unsalted sauces to substitute for salt, using salt alternatives, and by reading the restaurant nutrition information and Nutrition Facts labels to manage sodium consumption. The Dietary Approaches to Stop Hypertension diet, known as the DASH diet, together with sodium reduction, have shown success in decreasing high blood pressure [14, 16]. The DASH diet is a heart-healthy diet that recommends maintaining a balanced eating plan including vegetables, fruit, and whole grains, beans, fish, poultry, nuts, and vegetable oil while limiting added sugar, sugar-sweetened beverages, and saturated fat [17]. Collaborative partnerships will increase awareness of the salt content in commercially prepared food, gradually decrease the amount of sodium in processed food, increase low-salt food choices, and encourage innovative product reformulation while maintaining food safety. To that end, salt reduction or substitution initiatives have been successful internationally in other countries such as Canada, the UK, and China [18-21].
In closing, a multidimensional approach to decreasing sodium intake is consistent with the 2020-2025 Dietary Guidelines for Americans. Concerted efforts by the government, FDA, the food manufacturing industry, and stakeholders at the population-level and the public at the individual-level to decrease salt intake would be needed for a long-term sustainable behavior change in reducing salt consumption. These complementary efforts will provide economic benefits and public health services to decrease health disparities and alleviate the burden of preventable diet-related chronic diseases such as hypertension and cardiovascular disease.
By Ghada Soliman, MD, PhD, RD, CDN
Ghada Soliman is an Associate Professor of nutrition at the CUNY Graduate School of Public Health & Health Policy and a faculty fellow of the CUNY Urban Food Policy Institute.
References
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