Janelle P. Gunn

Sodium and potassium intakes among US adults: NHANES 2003–2008

BACKGROUND The American Heart Association (AHA), Institute of Medicine (IOM), and US Departments of Health and Human Services and Agriculture (USDA) Dietary Guidelines for Americans all recommend that Americans limit sodium intake and choose foods that contain potassium to decrease the risk of hypertension and other adverse health outcomes. OBJECTIVE We estimated the distributions of usual daily sodium and potassium intakes by sociodemographic and health characteristics relative to current recommendations. DESIGN We used 24-h dietary recalls and other data from 12,581 adults aged ≥20 y who participated in NHANES in 2003-2008. Estimates of sodium and potassium intakes were adjusted for within-individual day-to-day variation by using measurement error models. SEs and 95% CIs were assessed by using jackknife replicate weights. RESULTS Overall, 99.4% (95% CI: 99.3%, 99.5%) of US adults consumed more sodium daily than recommended by the AHA (<1500 mg), and 90.7% (89.6%, 91.8%) consumed more than the IOM Tolerable Upper Intake Level (2300 mg). In US adults who are recommended by the Dietary Guidelines to further reduce sodium intake to 1500 mg/d (ie, African Americans aged ≥51 y or persons with hypertension, diabetes, or chronic kidney disease), 98.8% (98.4%, 99.2%) overall consumed >1500 mg/d, and 60.4% consumed >3000 mg/d-more than double the recommendation. Overall, <2% of US adults and ~5% of US men consumed ≥4700 mg K/d (ie, met recommendations for potassium). CONCLUSION Regardless of recommendations or sociodemographic or health characteristics, the vast majority of US adults consume too much sodium and too little potassium.

Sodium Intake and Blood Pressure Among US Children and Adolescents

OBJECTIVE: To assess the association between usual dietary sodium intake and blood pressure among US children and adolescents, overall and by weight status. METHODS: Children and adolescents aged 8 to 18 years (n = 6235) who participated in NHANES 2003–2008 comprised the sample. Subjects’ usual sodium intake was estimated by using multiple 24-hour dietary recalls. Linear or logistic regression was used to examine association between sodium intake and blood pressure or risk for pre-high blood pressure and high blood pressure (pre-HBP/HPB). RESULTS: Study subjects consumed an average of 3387 mg/day of sodium, and 37% were overweight/obese. Each 1000 mg per day sodium intake was associated with an increased SD score of 0.097 (95% confidence interval [CI] 0.006–0.188, ∼1.0 mm Hg) in systolic blood pressure (SBP) among all subjects and 0.141 (95% CI: –0.010 to 0.298, ∼1.5 mm Hg) increase among overweight/obese subjects. Mean adjusted SBP increased progressively with sodium intake quartile, from 106.2 mm Hg (95% CI: 105.1–107.3) to 108.8 mm Hg (95% CI: 107.5–110.1) overall (P = .010) and from 109.0 mm Hg (95% CI: 107.2–110.8) to 112.8 mm Hg (95% CI: 110.7–114.9; P = .037) among those overweight/obese. Adjusted odds ratios comparing risk for pre-HBP/HPB among subjects in the highest versus lowest sodium intake quartile were 2.0 (95% CI: 0.95–4.1, P = .062) overall and 3.5 (95% CI: 1.3–9.2, P = .013) among those overweight/obese. Sodium intake and weight status appeared to have synergistic effects on risk for pre-HBP/HPB (relative excess risk for interaction = 0.29 (95% CI: 0.01–0.90, P < .05). CONCLUSIONS: Sodium intake is positively associated with SBP and risk for pre-HBP/HPB among US children and adolescents, and this association may be stronger among those who are overweight/obese.

Sodium and Sugar in Complementary Infant and Toddler Foods Sold in the United States

OBJECTIVES: To evaluate the sodium and sugar content of US commercial infant and toddler foods. METHODS: We used a 2012 nutrient database of 1074 US infant and toddler foods and drinks developed from a commercial database, manufacturer Web sites, and major grocery stores. Products were categorized on the basis of their main ingredients and the US Food and Drug Administration’s reference amounts customarily consumed per eating occasion (RACC). Sodium and sugar contents and presence of added sugars were determined. RESULTS: All but 2 of the 657 infant vegetables, dinners, fruits, dry cereals, and ready-to-serve mixed grains and fruits were low sodium (≤140 mg/RACC). The majority of these foods did not contain added sugars; however, 41 of 79 infant mixed grains and fruits contained ≥1 added sugar, and 35 also contained >35% calories from sugar. Seventy-two percent of 72 toddler dinners were high in sodium content (>210 mg/RACC). Toddler dinners contained an average of 2295 mg of sodium per 1000 kcal (sodium 212 mg/100 g). Savory infant/toddler snacks (n = 34) contained an average of sodium 1382 mg/1000 kcal (sodium 486 mg/100 g); 1 was high sodium. Thirty-two percent of toddler dinners and the majority of toddler cereal bars/breakfast pastries, fruit, and infant/toddler snacks, desserts, and juices contained ≥1 added sugar. CONCLUSIONS: Commercial toddler foods and infant or toddler snacks, desserts, and juice drinks are of potential concern due to sodium or sugar content. Pediatricians should advise parents to look carefully at labels when selecting commercial toddler foods and to limit salty snacks, sweet desserts, and juice drinks.

Progress toward sodium reduction in the United States

The average adult in the United States of America consumes well above the recommended daily limit of sodium. Average sodium intake is about 3 463 mg/day, as compared to the 2010 dietary guidelines for Americans recommendation of < 2 300 mg/day. A further reduction to 1 500 mg/day is advised for people 51 years or older; African Americans; and people with high blood pressure, diabetes, or chronic kidney disease. In the United States of America, the problem of excess sodium intake is related to the food supply. Most sodium consumed comes from packaged, processed, and restaurant foods and therefore is in the product at the time of purchase. This paper describes sodium reduction policies and programs in the United States at the federal, state, and local levels; efforts to monitor the health impact of sodium reduction; ways to assess consumer knowledge, attitudes, and behavior; and how these activities depend on and inform global efforts to reduce sodium intake. Reducing excess sodium intake is a public health opportunity that can save lives and health care dollars in the United States and globally. Future efforts, including sharing successes achieved and barriers identified in the United States and globally, may quicken and enhance progress.

Sodium content of popular commercially processed and restaurant foods in the United States

Purpose The purpose of this study was to provide baseline estimates of sodium levels in 125 popular, sodium-contributing, commercially processed and restaurant foods in the U.S., to assess future changes as manufacturers reformulate foods. Methods In 2010–2013, we obtained ~ 5200 sample units from up to 12 locations and analyzed 1654 composites for sodium and related nutrients (potassium, total dietary fiber, total and saturated fat, and total sugar), as part of the U.S. Department of Agriculture-led sodium-monitoring program. We determined sodium content as mg/100 g, mg/serving, and mg/kcal and compared them against U.S. Food and Drug Administrations (FDA) sodium limits for “low” and “healthy” claims and to the optimal sodium level of < 1.1 mg/kcal, extrapolating from the Healthy Eating Index-2010. Results Results from this study represent the baseline nutrient values to use in assessing future changes as foods are reformulated for sodium reduction. Sodium levels in over half (69 of 125) of the foods, including all main dishes and most Sentinel Foods from fast-food outlets or restaurants (29 of 33 foods), exceeded the FDA sodium limit for using the claim “healthy”. Only 13 of 125 foods had sodium values below 1.1 mg/kcal. We observed a wide range of sodium content among similar food types and brands. Conclusions Current sodium levels in commercially processed and restaurant foods in the U.S. are high and variable. Targeted benchmarks and increased awareness of high sodium content and variability in foods would support reduction of sodium intakes in the U.S.

Iodized salt sales in the United States.

Iodized salt has been an important source of dietary iodine, a trace element important for regulating human growth, development, and metabolic functions. This analysis identified iodized table salt sales as a percentage of retail salt sales using Nielsen ScanTrack. We identified 1117 salt products, including 701 salt blends and 416 other salt products, 57 of which were iodized. When weighted by sales volume in ounces or per item, 53% contained iodized salt. These findings may provide a baseline for future monitoring of sales of iodized salt.

Reducing sodium intake at the community level: the sodium reduction in communities program.

Approximately 90% of Americans aged 2 years or older consume too much sodium (1). The consumption of too much sodium increases blood pressure, which increases the risk for stroke, coronary heart disease, heart failure, and renal disease (2). Population-based strategies to reduce salt intake are cost-effective, can reduce blood pressure (3), and, according to the Institute of Medicine, are needed at national, state, and community levels (2). To improve food environments and reduce sodium intake at the community level, the Centers for Disease Control and Prevention (CDC) funds the Sodium Reduction in Communities Program (SRCP). This demonstration project supports communities in creating more healthful food environments and aims to expand the evidence base for effective community strategies to address sodium intake at the population level. In this article, we describe the role of communities and environments in influencing health and strategies being implemented and evaluated by SRCP communities.

Sodium Intake among US School-Aged Children: National Health and Nutrition Examination Survey, 2011-2012

BACKGROUND Identifying current major dietary sources of sodium can enhance strategies to reduce excess sodium intake, which occurs among 90% of US school-aged children. OBJECTIVE To describe major food sources, places obtained, and eating occasions contributing to sodium intake among US school-aged children. DESIGN Cross-sectional analysis of data from the 2011-2012 National Health and Nutrition Examination Survey. PARTICIPANTS/SETTING A nationally representative sample of 2,142 US children aged 6 to 18 years who completed a 24-hour dietary recall. MAIN OUTCOME MEASURES Population proportions of sodium intake from major food categories, places, and eating occasions. STATISTICAL ANALYSES PERFORMED Statistical analyses accounted for the complex survey design and sampling. Wald F tests and t tests were used to examine differences between subgroups. RESULTS Average daily sodium intake was highest among adolescents aged 14 to 18 years (3,565±120 mg), lowest among girls (2,919±74 mg). Little variation was seen in average intakes or the top five sodium contributors by sociodemographic characteristics or weight status. Ten food categories contributed to almost half (48%) of US school-aged childrens sodium intake, and included pizza, Mexican-mixed dishes, sandwiches, breads, cold cuts, soups, savory snacks, cheese, plain milk, and poultry. More than 80 food categories contributed to the other half of childrens sodium intake. Foods obtained from stores contributed 58% of sodium intake, fast-food/pizza restaurants contributed 16%, and school cafeterias contributed 10%. Thirty-nine percent of sodium intake was consumed at dinner, 31% at lunch, 16% from snacks, and 14% at breakfast. CONCLUSIONS With the exception of plain milk, which naturally contains sodium, the top 10 food categories contributing to US schoolchildrens sodium intake during 2011-2012 comprised foods in which sodium is added during processing or preparation. Sodium is consumed throughout the day from multiple foods and locations, highlighting the importance of sodium reduction across the US food supply.

Top sources of dietary sodium from birth to age 24 mo, United States, 2003–2010

BACKGROUND Sodium intake is high in US children. Data are limited on the dietary sources of sodium, especially from birth to age 24 mo. OBJECTIVE We identified top sources of dietary sodium in US children from birth to age 24 mo. DESIGN Data from the NHANES 2003-2010 were used to examine food sources of sodium (population proportions and mean intakes) in 778 participants aged 0-5.9 mo, 914 participants aged 6-11.9 mo, and 1219 participants aged 12-23.9 mo by sociodemographic characteristics. RESULTS Overall, mean dietary sodium intake was low in 0-5.9-mo-old children, and the top contributors were formula (71.7%), human milk (22.9%), and commercial baby foods (2.2%). In infants aged 6-11.9 mo, the top 5 contributors were formula (26.7%), commercial baby foods (8.8%), soups (6.1%), pasta mixed dishes (4.0%), and human milk (3.9%). In children aged 12-23.9 mo, the top contributors were milk (12.2%), soups (5.4%), cheese (5.2%), pasta mixed dishes (5.1%), and frankfurters and sausages (4.6%). Despite significant variation in top food categories across racial/ethnic groups, commercial baby foods were a top food contributor in children aged 6-11.9 mo, and frankfurters and sausages were a top food contributor in children aged 12-23.9 mo. The top 5 food categories that contributed to sodium intake also differed by sex. Most of the sodium consumed (83-90%) came from store foods (e.g., from the supermarket). In children aged 12-23.9 mo, 9% of sodium consumed came from restaurant foods, and 4% of sodium came from childcare center foods. CONCLUSIONS The vast majority of sodium consumed comes from foods other than infant formula or human milk after the age of 6 mo. Although the majority of sodium intake was from store foods, after age 12 mo, restaurant foods contribute significantly to intake. Reducing the sodium content in these settings would reduce sodium intake in the youngest consumers.

Are Reductions in Population Sodium Intake Achievable

The vast majority of Americans consume too much sodium, primarily from packaged and restaurant foods. The evidence linking sodium intake with direct health outcomes indicates a positive relationship between higher levels of sodium intake and cardiovascular disease risk, consistent with the relationship between sodium intake and blood pressure. Despite communication and educational efforts focused on lowering sodium intake over the last three decades data suggest average US sodium intake has remained remarkably elevated, leading some to argue that current sodium guidelines are unattainable. The IOM in 2010 recommended gradual reductions in the sodium content of packaged and restaurant foods as a primary strategy to reduce US sodium intake, and research since that time suggests gradual, downward shifts in mean population sodium intake are achievable and can move the population toward current sodium intake guidelines. The current paper reviews recent evidence indicating: (1) significant reductions in mean population sodium intake can be achieved with gradual sodium reduction in the food supply, (2) gradual sodium reduction in certain cases can be achieved without a noticeable change in taste or consumption of specific products, and (3) lowering mean population sodium intake can move us toward meeting the current individual guidelines for sodium intake.