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ARS Home » Northeast Area » Beltsville, Maryland (BHNRC) » Beltsville Human Nutrition Research Center » Nutrient Data Laboratory » Research » Publications at this Location » Publication #344731
Title: Comparison of label and laboratory sodium values in popular sodium-contributing foods in the United States

Author
item Ahuja, Jaspreet
item LI, YING - University Of Maryland
item Nickle, Melissa
item Haytowitz, David
item ROSELAND, JANET - University Of Maryland
item NGUYEN, QUYNHANH - University Of Maryland
item KHAN, MONA - University Of Maryland
item Wu, Xianli
item SOMANCHI, MEENA - University Of Maryland
item Williams, Juhi
item Pehrsson, Pamela
item COGSWELL, MARY - Centers For Disease Control And Prevention (CDC) - United States

Submitted to: Journal of the Academy of Nutrition and Dietetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/31/2018
Publication Date: 11/13/2018
Citation: Ahuja, J.K., Li, Y., Nickle, M.S., Haytowitz, D.B., Roseland, J., Nguyen, Q., Khan, M., Wu, X., Somanchi, M., Williams, J.R., Pehrsson, P.R., Cogswell, M. 2018. Comparison of label and laboratory sodium values in popular sodium-contributing foods in the United States. Journal of the Academy of Nutrition and Dietetics. https://doi.org/10.1016/j.jand.2018.08.155.
DOI: https://doi.org/10.1016/j.jand.2018.08.155

Interpretive Summary: Nutrition labels are important tools for consumers and for supporting public health strategies. Recent published comparison of label and laboratory sodium values for U.S. foods, and differences by brand type (national, private-label) or source (store, restaurant) is unavailable. In 2010–2014, Nutrient Data Laboratory (NDL) of the U.S. Department of Agriculture collected 3,432 samples nationwide of 125 foods and chemically analyzed them. For this post-hoc analysis, NDL linked laboratory values for 1,390 composites of 114 foods to corresponding label or website (restaurant) nutrient values, and determined the ratio of laboratory to label value. This study provides a cross-sectional comparison of laboratory and label sodium and related nutrient values (total fat, saturated fat, total sugar) of foods that are among the top sodium contributors to the U.S. diet. For sodium, 5% of the composites had laboratory to label values higher than 120% and 14% had ratios lower or equal to 80%. Our study shows that the majority of label and laboratory values sampled agree and under-declaration of label values (i.e. ratios greater than 120%) is limited. However, there is some discrepancies between label and laboratory values. Periodic monitoring of the nutrient content of foods through laboratory analyses establishes validity of the food labels and helps identify foods and food categories where the label and laboratory values do not compare well, and hence may need laboratory analyses to support accuracy of nutrient databases. The results from the study provide several insights for the federal sodium-monitoring project, for database developers, and clinicians.

Technical Abstract: Nutrition labels are important tools for consumers and for supporting public health strategies. Recent published comparison of label and laboratory sodium values for U.S. foods, and differences by brand type (national, private-label) or source (store, restaurant) is unavailable. The objective for this study is to compare label and laboratory values for sodium and related nutrients (total sugars, total fat and saturated fat) in popular, sodium-contributing foods, and examine if there are differences by brand type and source. In 2010–2014, Nutrient Data Laboratory (NDL) of the U.S. Department of Agriculture collected 3,432 samples nationwide of 125 foods and chemically analyzed them. For this post-hoc analysis, NDL linked laboratory values for 1,390 composites (one or more samples of the same food) of 114 foods to corresponding label or website (restaurant) nutrient values. For each composite and food, the ratio of laboratory to label value was determined. NDL considered ratios > 120% or = 80% as criteria for the values not agreeing for purposes of this study. Mean label and laboratory nutrient values for each food category were determined and tested for significance (p < 0.05) using Wilcoxon Signed Rank test. For sodium, 5% of the composites had laboratory to label values higher than 120% and 14% had ratios lower or equal to 80%. There was substantial variability in the discrepancies between label and laboratory values. Our study shows that the majority of label and laboratory values sampled agree and under-declaration of label values (i.e. ratios greater than 120%) is limited. However, there is some disagreement. Periodic monitoring of the nutrient content of foods through laboratory analyses establishes validity of the food labels and helps identify foods and food categories where the label and laboratory values do not compare well, and hence may need laboratory analyses to support accuracy of nutrient databases.