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OBJECTIVES: Data on the iodine content of foods are needed to assess intake and plan dietary guidance. Iodine is central for thyroid function in human growth, reproduction, neurologic development and energy metabolism, and inadequate or excessive intakes can cause thyroid dysfunction and/or disease. Overall, U.S. iodine intake is sufficient, but some women of reproductive age and pregnant women may be at risk for deficiency, as well as people whose dietary patterns do not include iodine-rich foods. METHODS: A Special Interest Database (SID) was developed through the collaboration of the Methods and Application of Food Composition Laboratory (USDA), the Food and Drug Administration (FDA), and the Office of Dietary Supplements (NIH). Data for foods and beverages were derived from samples analyzed by USDA and the FDA Total Diet Study; foods included seaweed, fish and other seafood, dairy, iodized salt, eggs, and commercial foods; metadata were captured as varying iodine levels may arise from feed supplementation, iodophor use, and iodine-containing ingredients in processed foods. Samples were analyzed for iodine using inductively coupled plasma mass spectrometry (ICP-MS). Quality control included certified reference materials and secondary in-house controls. RESULTS: The Special Interest Database on Iodine (https://www.ars.usda.gov/northeast-area/beltsville-md-bhnrc/beltsville-human-nutrition-research-center/methods-and-application-of-food-composition-laboratory/mafcl-site-pages/iodine/) was released in 2020 and includes food descriptions, means, standard deviations, value ranges, sample sizes, and supporting information for 430 foods. Foods continue to be analyzed for iodine and added to the database. In addition, iodine intakes of the U.S. population are being calculated by mapping the iodine content of foods to food consumption data from the 2014 U.S. National Health and Nutrition Examination Survey (NHANES) and eventually more recent NHANES dietary data. CONCLUSIONS: The SID on Iodine and the mapped NHANES data provide needed information to monitor iodine status and develop dietary guidance for the general U.S. population and vulnerable subgroups. Furthermore, the database can provide a valuable tool for other research programs and clinical applications in iodine nutrition. FUNDING SOURCES: NIH Office of Dietary Supplements.

Data on the iodine content of foods and dietary supplements are needed to develop general population intake estimates and identify major contributors to intake. Samples of seafood, dairy products, eggs, baked products, salts, tap water, other foods and beverages, and dietary supplements were collected according to established sampling plans of the U.S. Department of Agriculture (USDA) and the U.S. Food and Drug Administration (FDA). Samples were assayed for iodine content using inductively coupled plasma mass spectrometry with rigorous quality control measures. The food data were released through a collaboration of USDA, FDA, and the Office of Dietary Supplements-National Institutes of Health (ODS-NIH) as the USDA, FDA, and ODS-NIH Database for the Iodine Content of Common Foods at www.ars.usda.gov/mafcl. Iodine data for dietary supplements are available in the ODS-USDA Dietary Supplement Ingredient Database and the ODS Dietary Supplement Label Database. Data from the iodine databases linked to national dietary survey data can provide needed information to monitor iodine status and develop dietary guidance for the general U.S. population and vulnerable subgroups. This iodine information is critical for dietary guidance development, especially for those at risk for iodine deficiency (i.e., women of reproductive age and young children). National Institutes of Health's Office of Dietary Supplements Published version This work was funded by the National Institutes of Health's Office of Dietary Supplements and in-kind contributions from the USDA and FDA. Public domain – authored by a U.S. government employee

Folate-containing prenatal supplements are commonly consumed in the United States, but inconsistencies in units of measure and chemical forms pose challenges for providing authoritative advice on recommended amounts. New regulations require folate to be declared as micrograms of dietary folate equivalents (DFE) on product labels, whereas intake recommendations for reducing the risk of neural tube defects (NTDs) and the Tolerable Upper Intake Level are expressed as micrograms of folic acid. Today, >25% of prenatal supplements contain folate as synthetic salts of L-5-methyltetrahydrofolate (L-5-MTHF), but recommendations do not include this form of the vitamin. Harmonizing units of measure and addressing newer forms of folate salts in intake recommendations and in the prevention of NTDs would resolve the confusion.

The Office of Dietary Supplements (ODS) at the NIH sponsored a workshop on May 12‐13, 2011, to bring together representatives from various NIH institutes and centers as a first step in developing an NIH iodine research initiative. The workshop also provided an opportunity to identify research needs that would inform the dietary reference intakes for iodine, which were last revised in 2001. Iodine is required throughout the life cycle, but pregnant women and infants are the populations most at risk of deficiency, because iodine is required for normal brain development and growth. The CDC monitors iodine status of the population on a regular basis, but the status of the most vulnerable populations remains uncertain. The NIH funds very little investigator-initiated research relevant to iodine and human nutrition, but the ODS has worked for several years with a number of other U.S. government agencies to develop many of the resources needed to conduct iodine research of high quality (e.g., validated analytical methods and reference materials for multiple types of samples). Iodine experts, scientists from several U.S. government agencies, and NIH representatives met for 2 d to identify iodine research needs appropriate to the NIH mission. J. Nutr. 142: 1175S‐1185S, 2012.

Sales of energy drinks in the United States reached $12.5 billion in 2012. Emergency department visits related to consumption of these products have increased sharply, and while these numbers remain small relative to product sales, they raise important questions regarding biological and behavioral effects. Although some common ingredients of energy drinks have been extensively studied (e.g., caffeine, B vitamins, sugars, inositol), data on other ingredients (e.g., taurine) are limited. Summarized here are data presented elsewhere in this issue on the prevalence and patterns of caffeine-containing energy drink use, the effects of these products on alertness, fatigue, cognitive functions, sleep, mood, homeostasis, as well as on exercise physiology and metabolism, and the biological mechanisms mediating the observed effects. There are substantial data on the effects of some energy drink ingredients, such as caffeine and sugars, on many of these outcomes; however, even for these ingredients many controversies and gaps remain, and data on other ingredients in caffeine-containing energy drinks, and on ingredient interactions, are sparse. This summary concludes with a discussion of critical gaps in the data and potential next steps.

Requiring active participation in nutrition education lessons at home with parents/caregivers may improve children's nutrition knowledge and adoption of healthful eating behaviors. The objective of this project was to develop interactive homework lessons for first- to fourth-grade students and their parents/caregivers and pilot test in the home setting using a collaborative model with Cooperative Extension Service educators serving as community partners with classroom teachers. Lesson content and behavioral strategies emphasized planning and assessing food choices and were based on needs assessment data from teachers and parents/caregivers of school-aged children with social learning theory as the theoretical framework for lesson development. Pre– and post–tests examining changes in parent and child knowledge and reported behavior showed positive changes but varied with grade level and lesson content. In future programs, the number of lessons offered and their complexity need to be carefully considered when implementing interactive homework lessons with families.

Over one-half of U.S. adults use dietary supplements, so federally supported research into the safety and effectiveness of these compounds is important for the health of many Americans. Data collected in the Computer Access to Research on Dietary Supplements database, which compiles federally sponsored dietary supplement-related research, are useful to scientists in determining the type of dietary supplement research that federal agencies are currently funding and where research gaps exist. This article describes the dietary supplement-related research funded by the NIH and the USDA. Between fiscal years 1999 and 2007, the number of research projects and funding for dietary supplement research more than doubled. During that period, NIH funded 6748 dietary supplement-related projects at a cost of $1.9 billion and the USDA funded 2258 projects at a cost of $347 million. The top funded dietary supplement ingredient categories were vitamins and minerals, botanicals, phytochemicals, and fatty acids. Cancer was by far the most frequent health outcome in dietary supplement research funding, nearly double the next closest health outcome category. Other health outcomes with the greatest funding were cellular and molecular mechanisms, cardiovascular health, women’s reproductive health, and immune function. The greatest number of dietary supplement research projects are funded by the NIH National Cancer Institute, the NIH National Center for Complementary and Alternative Medicine, the NIH Office of Dietary Supplements, and the USDA Agricultural Research Service.

Flaxseed, the richest known source of plant lignans, has been shown to have chemoprotective effects in animal and cell studies. Some of its effects may be mediated through its influence on endogenous hormone production and metabolism. Two competing pathways in estrogen metabolism involve production of the 2-hydroxylated and 16 alpha-hydroxylated metabolites. Because of the proposed differences in biological activities of these metabolites, the balance of the two pathways has been used as a biomarker for breast cancer risk. We examined the effects of flaxseed consumption on urinary estrogen metabolite excretion in postmenopausal women. Twenty-eight postmenopausal women were studied for three seven-week feeding periods in a randomized crossover design. During the feeding periods, subjects consumed their usual diets plus ground flaxseed (0, 5, or 10 g/day). Urinary excretion of the estrogen metabolites 2-hydroxyestrogen (2-OHEstrogen) and 16 alpha-hydroxyestrone (16 alpha-OHE1) as well as their ratio, 2/16 alpha-OHE1, was measured by enzyme immunoassay. Flaxseed supplementation significantly increased urinary 2-OHEstrogen excretion (p < 0.0005) and the urinary 2/16 alpha-OHE1 ratio (p < 0.05) in a linear, dose-response fashion. There were no significant differences in urinary 16 alpha-OHE1 excretion. These results suggest that flaxseed may have chemoprotective effects in postmenopausal women.