Location: Nutrient Data Laboratory
Project Number: 8040-52000-064-43-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Oct 1, 2016
End Date: Sep 30, 2018
The objective of this project is to develop an analytically derived dataset on iodine in major contributors of iodine in the US food supply. This is in keeping with the overall objective of: Develop and expand the USDA-ARS food composition databases to represent the dynamics of the U.S. food supply, including increased use of commercially packaged foods, restaurant foods, school foods, and ethnic foods. As we monitor sodium and related nutrients in commercially processed and restaurant foods in the US food supply and the use of iodized salt (not used in commercial applications) decreases, information on sources of iodine becomes of increasing importance. Development of authoritative food composition data and databases for components that may promote health such as iodine in thyroid health and prevention of fetal disorders (approximately 20% of women of reproductive age are potentially deficient) is as important as conventional nutrients. It is imperative to include these targeted foods, determine better estimates of variability among brands and types of foods e.g., different types of salmon, and other pertinent information (cultivar, weather, growing conditions, aquaculture information, etc.), which impact the nutrient values. The specific objective of this agreement is to prioritize Key Foods for iodine, sample according to a statistically defensible study design, analyze samples according to analytically acceptable methods, include appropriate Quality Control material in the sample stream, and analyze the data according to acceptable methods for the sample.
Improved food composition data and research focused in ongoing ARS programs will be established through small and large studies on the changing composition of the U.S. food supply. Emerging nutrients of public health importance e.g., iodine in the diets of vulnerable subgroups of the US population (women of reproductive age) will be studied and included in the USDA food composition database/s and associated research products and databases. This includes monitoring and analysis of key contributors of iodine through development of Key Foods list and including commercially processed foods, seafood/seaweed, retail salts, and foods expected to contain either naturally occurring iodine or additives/salt which contains iodine. Using current market share data and the established National Food and Nutrient Analysis Program protocols, foods will be sampled and analyzed according to a statistically defensible sampling design, across the country (and in some cases, previously sampled iodine-containing samples). Using inductively coupled plasma mass spectroscopy (ICP-MS) and reference materials from the National Institute of Standards and Technology (NIST 1548a Freeze Dried Typical Diet and NIST 1849a Infant/Adult Nutritional Formula), a pilot study to determine stability of iodine in a mixed matrix food stored at -60 will determine if the archived samples are still useable. In addition, a stability study will be conducted to determine if previously collected multi-ingredient samples are acceptable to use. Relying on archived samples as part of the sample pool, 500-600 samples will be tested for iodine content; archived samples will be retained on all in the event of a need for repeat analyses. Information on the samples (origin, package information, type e.g., salmon, etc.) will be stored in the Virginia Tech Sample Tracking Database for inclusion in the dataset in the ARS Foods Data System (ARS FooDS).