Racial/Ethnic and Income Disparities in the Sodium Content of Packaged Food Purchases by US Households in the Past 15 Years
Authors: Poti Jennifer M , Dunford Elizabeth , Popkin Barry M 
Published: November 2023

Background

The high sodium content of packaged foods contributes to excess dietary sodium intake among Americans and has therefore been targeted for reduction by manufacturer and retailer initiatives. However, it remains unknown whether sociodemographic disparities in the sodium content of food purchases exist and have changed over time, potentially contributing to disparities in sodium intake and hypertension.

Objectives

The aims of our study were to determine whether declines in the sodium content of packaged food purchases between 2000 and 2013 differed by income or race/ethnic group, evaluate whether disparities in the sodium content of purchases persisted across time, and identify subpopulation differences in top food group contributors to sodium in food purchases.

Methods

This study analyzed data from the 2000–2013 Homescan panel, a nationally representative longitudinal study of US households (n=164,084) that record all consumer packaged goods (CPG) foods and beverages purchased from retail food stores throughout the year by barcode scanning. Brand‐ and product‐specific nutrition information for over 1.2 million barcoded products was used. Survey‐weighted unadjusted trends in sodium content of purchases and mean contribution from specific food groups were compared by household income, expressed as a percent of the Federal Poverty Level (% FPL), for low (≤185% FPL), medium (186–400% FPL), and high (>400% FPL) income households, and by race/ethnicity for non‐Hispanic white (NHW), non‐Hispanic black (NHB), and Hispanic households.

Results

High income households had significantly larger decreases in the sodium content of household CPG food purchases between 2000 and 2013 (β = −581 mg/1000 g, 95% CI: −628, −534) compared to low income households (β = −407 mg/1000 g, 95% CI: −484, −331) (p<0.001). Consequently, income disparities widened across time, with the sodium content of CPG food purchases significantly higher for low income (4481 ± 19 mg/1000 g) compared to high income (4076 ± 15 mg/1000 g) households in 2013. Although declines in the sodium content of CPG food purchases were significantly greater among NHB (β = −685 mg/1000 g, 95% CI: −814, −557) compared to NHW (β = −432 mg/1000 g, 95% CI: −462, −402) households (p<0.001), NHB households continued to have higher sodium content for CPG food purchases (4846 ± 35 mg/1000 g) compared to NHW households (4179 ± 10 mg/1000 g) in 2013 (p<0.001) and at all time points.

Prepared meals/mixed dishes, soup, and processed meat were greater contributors to sodium in CPG purchases for low vs high income households. Compared to NHW, condiments/sauces and processed meat were greater contributors to sodium in purchases for NHB households. Table salt and seasoning products were significantly greater sources of sodium for low income (446 ± 8 mg/d) vs high income (367 ± 6 mg/d) households and significantly greater for NHB (599 ± 14 mg/d) vs NHW households (362 ± 4 mg/d) in 2013 and at all time points.

Conclusions

Recent initiatives to reduce the sodium content of US packaged foods may not be reaching low income households. Disparities in the sodium content of CPG food purchases widened across income groups and persisted across race/ethnic groups, suggesting that future industry and public health efforts are needed to target the foods and brands preferentially purchased by NHB and low income households for sodium reduction.

Support or Funding Information

Funding for this study comes from the Robert Wood Johnson Foundation (Grants 67506, 68793, 70017, 71837), NIH (R01DK098072), and the CPC 5 R24 HD050924.