Iodine in food and dietary supplement composition databases

Authors: Pehrsson, Pamela; PATTERSON, KRISTINE - Consultant; SPUNGEN, JUDITH - Food And Drug Administration(FDA); WIRTZ, MARK - Food And Drug Administration(FDA); ANDREWS, KAREN - Consultant; DWYER, JOHANNA - National Institutes Of Health (NIH); SWANSON, CHRISTINE - National Institutes Of Health (NIH)

Submitted to: The American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/16/2015
Publication Date: 8/27/2016
Publication URL: https://handle.nal.usda.gov/10113/62842
Citation: Pehrsson, P.R., Patterson, K.Y., Spungen, J.H., Wirtz, M.S., Andrews, K.W., Dwyer, J.T., Swanson, C.A. 2016. Iodine in food and dietary supplement composition databases. American Journal of Clinical Nutrition. ajcn 110064.

Interpretive Summary: For a number of years, the U.S. Food and Drug Administration (FDA) and the Nutrient Data Laboratory (NDL) of the U.S. Department of Agriculture’s Agricultural Research Service have worked independently on determining the iodine content of foods and dietary supplements and are now harmonizing their efforts. The objective of the current paper is to describe the harmonization plan and the results of initial iodine analyses accomplished under that plan. For many years, the FDA’s Total Diet Study (TDS) has measured iodine concentrations in selected foods collected in four regions of the country each year. For over a decade, the NDL has collected and analyzed foods as part of the National Food and Nutrient Analysis Program; iodine analysis is now being added to the program. NDL recently qualified a commercial laboratory to conduct iodine analysis of foods using an inductively coupled plasma mass spectrometry (ICP-MS) method. Co-analysis of a set of samples by the commercial laboratory using the ICP-MS method and the FDA laboratory using its standard colorimetric method yielded comparable results. FDA recently reviewed historical TDS data for trends in the iodine content of selected foods, and the NDL analyzed samples of a limited subset of those foods for iodine. FDA and NDL are working to combine their data on iodine in foods and to produce an online database that can be used for estimating iodine intake from food in the U.S. population. In addition, NDL continues to analyze dietary supplements for iodine and, in collaboration with the National Institutes of Health’s Office of Dietary Supplements, to publish the data online in the Dietary Supplement Ingredient Database. The goal is to provide, through these two harmonized databases and the continuing TDS focus on iodine, improved tools for estimating iodine intake in population studies.

Technical Abstract: For a number of years, the U.S. Food and Drug Administration (FDA) and the Nutrient Data Laboratory (NDL) of the U.S. Department of Agriculture’s Agricultural Research Service have worked independently on determining the iodine content of foods and dietary supplements and are now harmonizing their efforts. The objective of the current paper is to describe the harmonization plan and the results of initial iodine analyses accomplished under that plan. For many years, the FDA’s Total Diet Study (TDS) has measured iodine concentrations in selected foods collected in four regions of the country each year. For over a decade, the NDL has collected and analyzed foods as part of the National Food and Nutrient Analysis Program; iodine analysis is now being added to the program. NDL recently qualified a commercial laboratory to conduct iodine analysis of foods using an inductively coupled plasma mass spectrometry (ICP-MS) method. Co-analysis of a set of samples by the commercial laboratory using the ICP-MS method and the FDA laboratory using its standard colorimetric method yielded comparable results. FDA recently reviewed historical TDS data for trends in the iodine content of selected foods, and the NDL analyzed samples of a limited subset of those foods for iodine. FDA and NDL are working to combine their data on iodine in foods and to produce an online database that can be used for estimating iodine intake from food in the U.S. population. In addition, NDL continues to analyze dietary supplements for iodine and, in collaboration with the National Institutes of Health’s Office of Dietary Supplements, to publish the data online in the Dietary Supplement Ingredient Database. The goal is to provide, through these two harmonized databases and the continuing TDS focus on iodine, improved tools for estimating iodine intake in population studies.