Iodine in Foods and Dietary Supplements: A Collaborative Database Developed by NIH, FDA and USDA.

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).

Do Multivitamin/Mineral Dietary Supplements for Young Children Fill Critical Nutrient Gaps?

BACKGROUND: Nearly a third of young US children take multivitamin/mineral (MVM) dietary supplements, yet it is unclear how formulations compare with requirements. OBJECTIVE: Describe the number and amounts of micronutrients contained in MVMs for young children and compare suggested amounts on product labels to micronutrient requirements. DESIGN: Cross-sectional. SETTING: All 288 MVMs on the market in the United States in the National Institutes of Health's Dietary Supplement Label Database in 2018 labeled for children 1 to <4 years old. MAIN OUTCOME MEASURES: Number of MVM products and amounts per day of micronutrients in each product suggested on labels compared with requirements represented by age-appropriate Daily Values (DV). Micronutrients of public health concern identified by the Dietary Guidelines for Americans (DGA) 2015-2020 (DGA 2015) and DGA 2020-2025 (DGA 2020) or those of concern for exceeding the upper tolerable intake levels. STATISTICAL ANALYSES: Number of products and percent DV per day provided by each micronutrient in each product. RESULTS: The 288 MVMs contained a mean of 10.1 ± 2.27 vitamins and 4.59 ± 2.27 minerals. The most common were, in rank order, vitamins C, A, D, E, B6, B12; zinc, biotin, pantothenic acid, iodine, and folic acid. For micronutrients denoted by the DGA 2015 and DGA 2020 of public health concern, 56% of the 281 products containing vitamin D, 4% of the 144 with calcium, and none of the 60 containing potassium provided at least half of the DV. The upper tolerable intake level was exceeded by 49% of 197 products with folic acid, 17% of 283 with vitamin A, and 14% of 264 with zinc. Most MVMs contained many of 16 other vitamins and minerals identified in national surveys as already abundant in children's diets. CONCLUSIONS: A reexamination of the amounts and types of micronutrients in MVMs might consider formulations that better fill critical gaps in intakes and avoid excess.

Analytical Challenges and Metrological Approaches to Ensuring Dietary Supplement Quality: International Perspectives.

The increased utilization of metrology resources and expanded application of its' approaches in the development of internationally agreed upon measurements can lay the basis for regulatory harmonization, support reproducible research, and advance scientific understanding, especially of dietary supplements and herbal medicines. Yet, metrology is often underappreciated and underutilized in dealing with the many challenges presented by these chemically complex preparations. This article discusses the utility of applying rigorous analytical techniques and adopting metrological principles more widely in studying dietary supplement products and ingredients, particularly medicinal plants and other botanicals. An assessment of current and emerging dietary supplement characterization methods is provided, including targeted and non-targeted techniques, as well as data analysis and evaluation approaches, with a focus on chemometrics, toxicity, dosage form performance, and data management. Quality assessment, statistical methods, and optimized methods for data management are also discussed. Case studies provide examples of applying metrological principles in thorough analytical characterization of supplement composition to clarify their health effects. A new frontier for metrology in dietary supplement science is described, including opportunities to improve methods for analysis and data management, development of relevant standards and good practices, and communication of these developments to researchers and analysts, as well as to regulatory and policy decision makers in the public and private sectors. The promotion of closer interactions between analytical, clinical, and pharmaceutical scientists who are involved in research and product development with metrologists who develop standards and methodological guidelines is critical to advance research on dietary supplement characterization and health effects.

Disintegration and Dissolution Testing of Green Tea Dietary Supplements: Application and Evaluation of United States Pharmacopeial Standards.

Approved performance quality tests are lacking in the United States Pharmacopeia (USP) for dietary supplements (DSs) containing green tea extracts. We evaluated the applicability of USP <2040 > general chapter protocols for disintegration and dissolution testing of botanicals to GT DSs. Of 28 single-ingredient GT DSs tested in 2 to 4 lots, 9 (32.1%) always passed the disintegration test, 8 (28.6%) always failed, and 11 (39.3%) showed inconsistent results. Of 34 multi-ingredient DSs tested in 2 lots, 21 (61.8%) passed and 8 (23.5%) failed in both lots, and 5 (14.7%) exhibited inconsistent performance. When stronger destructive forces were applied (disk added), all of the capsules that had failed initially, but not the tablets, passed. In dissolution testing, for the release of epigallocatechin-3-gallate (EGCG), only 6 of 20 single-ingredient DSs passed. Unexpectedly, with the addition of pepsin (prescribed by USP), only one additional DS passed. These results raise concerns that EGCG was not released properly from GT DS dosage forms. However, the general USP protocols may be inadequate for this botanical. More biorelevant destructive forces may be needed to break down capsules and tablets strengthened by the EGCG's interaction with shell material and to overcome the inhibition of digestive enzymes by EGCG.

Challenges in Developing Analytically Validated Laboratory-Derived Dietary Supplement Databases.

The Dietary Supplement Label Database (DSLD) is sponsored by the Office of Dietary Supplements (ODS) and the National Library of Medicine (NLM). It provides a searchable, free database of the contents of ∼65,000 supplement labels. A companion database of analytically verified product labels [the Dietary Supplement Ingredient Database (DSID)] was created by ODS, NLM, and the USDA. There are considerable challenges to populating both databases, but the DSID faces unique analytic chemistry challenges. This article describes the challenges to creating analytically verified marketplace surveys of dietary supplement (DS) product content claims for inclusion in public databases. Nutritionists and public health scientists require information on actual exposures to DS constituents because labeled content may not match labeled product content. Analytic verification of composition of DSs provides a link to actual exposure. A public database of analytically derived DS content was developed to provide more accurate estimates of dietary intake in population-based epidemiologic studies. The DSID has conducted surveys of several types of vitamin- and mineral-containing DSs. Results showing label content claims as analytically derived values are available in the current DSID. A recent pilot project explored the feasibility of adding botanical DS products to the DSID. Candidates for future botanical DSID studies will be based on sales volume, potential public health impacts, and the availability of validated analytic methods and reference materials. Databases like DSID and the DSLD are essential for researchers and clinicians to evaluate dietary ingredient intakes in population-based epidemiologic studies. Together, these databases provide a picture of the DS marketplace. The DSID provides an analytic survey of marketed DSs. However, selection of future botanical supplements for DSID evaluation involves analytic challenges. Even when appropriate resources are available, method selection and data evaluation are resource- and time-consuming.

Dietary Supplement Ingredient Database (DSID) and the Application of Analytically Based Estimates of Ingredient Amount to Intake Calculations.

OBJECTIVE: We describe the purpose of the Dietary Supplement Ingredient Database (DSID), the statistical methodology underlying online calculators of analytically verified supplement content estimates, and the application and significance of DSID label adjustments in nutritional epidemiology. BACKGROUND AND HISTORY: During dietary supplement (DS) manufacturing, many ingredients are added at higher than declared label amounts, but overages are not standardized among manufacturers. As a result, researchers may underestimate nutrient intakes from DSs. The DSID provides statistical tools on the basis of the results of chemical analysis to convert label claims into analytically predicted ingredient amounts. These adjustments to labels are linked to DS products reported in NHANES. RATIONALE: Tables summarizing the numbers of NHANES DS products with ingredient overages and below label content show the importance of DSID adjustments to labels for accurate intake calculations. RECENT DEVELOPMENTS: We show the differences between analytically based estimates and labeled content for vitamin D, calcium, iodine, caffeine, and omega-3 (n-3) fatty acids and their potential impact on the accuracy of intake assessments in large surveys. Analytical overages >20% of label levels are predicted for several nutrients in 50-99% of multivitamin-mineral products (MVMs) reported in NHANES: for iodine and selenium in adult MVMs, for iodine and vitamins D and E in children's MVMs, and for iodine, chromium, and potassium in nonprescription prenatal MVMs. Predicted overages of 10-20% for calcium can be applied to most MVMs and overages >10% for folic acid in the vast majority of adult and children's MVMs. FUTURE DIRECTIONS: DSID studies are currently evaluating ingredient levels in prescription prenatal MVMs and levels of constituents in botanical DSs. CONCLUSIONS: We estimate that the majority of MVM products reported in NHANES have significant overages for several ingredients. It is important to account for nonlabeled additional nutrient exposure from DSs to better evaluate nutritional status in the United States.

The Dietary Supplement Label Database: Recent Developments and Applications.

Objective: To describe the history, key features, recent enhancements, and common applications of the Dietary Supplement Label Database (DSLD). Background and History: Although many Americans use dietary supplements, databases of dietary supplements sold in the United States have not been widely available. The DSLD, an easily accessible public-use database was created in 2008 to provide information on dietary supplement composition for use by researchers and consumers. Rationale: Accessing current information easily and quickly is crucial for documenting exposures to dietary supplements because they contain nutrients and other bioactive ingredients that may have beneficial or adverse effects on human health. This manuscript details recent developments with the DSLD to achieve this goal and provides examples of how the DSLD has been used. Recent Developments: With periodic updates to track changes in product composition and capture new products entering the market, the DSLD currently contains more than 71,000 dietary supplement labels. Following usability testing with consumer and researcher user groups completed in 2016, improvements to the DSLD interface were made. As of 2017, both a desktop and mobile device version are now available. Since its inception in 2008, the use of the DSLD has included research, exposure monitoring, and other purposes by users in the public and private sectors. Future Directions: Further refinement of the user interface and search features to facilitate ease of use for stakeholders is planned. Conclusions: The DSLD can be used to track changes in product composition and capture new products entering the market. With over 71,000 DS labels it is a unique resource that policymakers, researchers, clinicians, and consumers may find valuable for multiple applications.

Is Nutrient Content and Other Label Information for Prescription Prenatal Supplements Different from Nonprescription Products?

BACKGROUND: Prenatal supplements are often recommended to pregnant women to help meet their nutrient needs. Many products are available, making it difficult to choose a suitable supplement because little is known about their labeling and contents to evaluate their appropriateness. OBJECTIVE: To determine differences between prescription and nonprescription prenatal supplements available in the United States regarding declared nutrient and nonnutrient ingredients and the presence of dosing and safety-related information. DESIGN: Using two publicly available databases with information about prenatal supplement products, information from prescription and nonprescription product labels were extracted and evaluated. For the 82 prescription and 132 nonprescription products, declared label amounts of seven vitamins and minerals, docosahexaenoic acid (DHA), the presence of other nonnutrient components, and the presence of key safety and informational elements as identified in two Department of Health and Human Services Office of Inspector General (OIG)'s 2003 reports were compiled and compared. RESULTS: Compared with nonprescription products, prescription products contained significantly fewer vitamins (9±0.2 vs 11±0.3; P≤0.05) and minerals (4±0.1 vs 8±0.3; P≤0.05). Declared amounts of folic acid were higher in prescription products, whereas vitamin A, vitamin D, iodine, and calcium were higher in the nonprescription products. Amounts of iron, zinc, and DHA were similar. Virtually all products contained levels of one or more nutrients that exceeded the Recommended Dietary Allowances for pregnant and/or lactating women. Product type also influenced ingredients added. Fewer prescription products contained botanical ingredients (6% prescription vs 33% nonprescription) and probiotics (2% prescription vs 8% nonprescription). Only prescription products contained the stool softener docusate sodium. CONCLUSIONS: Our analysis of prenatal supplements indicates that prescription and nonprescription supplements differ in terms of declared composition and nutrient strength, but have labels that are similarly sparse regarding aspects of use such as dosing information.

Analytical ingredient content and variability of adult multivitamin/mineral products: national estimates for the Dietary Supplement Ingredient Database.

BACKGROUND: Multivitamin/mineral products (MVMs) are the dietary supplements most commonly used by US adults. During manufacturing, some ingredients are added in amounts exceeding the label claims to compensate for expected losses during the shelf life. Establishing the health benefits and harms of MVMs requires accurate estimates of nutrient intake from MVMs based on measures of actual rather than labeled ingredient amounts. OBJECTIVES: Our goals were to determine relations between analytically measured and labeled ingredient content and to compare adult MVM composition with Recommended Dietary Allowances (RDAs) and Tolerable Upper Intake Levels. DESIGN: Adult MVMs were purchased while following a national sampling plan and chemically analyzed for vitamin and mineral content with certified reference materials in qualified laboratories. For each ingredient, predicted mean percentage differences between analytically obtained and labeled amounts were calculated with the use of regression equations. RESULTS: For 12 of 18 nutrients, most products had labeled amounts at or above RDAs. The mean measured content of all ingredients (except thiamin) exceeded labeled amounts (overages). Predicted mean percentage differences exceeded labeled amounts by 1.5-13% for copper, manganese, magnesium, niacin, phosphorus, potassium, folic acid, riboflavin, and vitamins B-12, C, and E, and by ∼25% for selenium and iodine, regardless of labeled amount. In contrast, thiamin, vitamin B-6, calcium, iron, and zinc had linear or quadratic relations between the labeled and percentage differences, with ranges from -6.5% to 8.6%, -3.5% to 21%, 7.1% to 29.3%, -0.5% to 16.4%, and -1.9% to 8.1%, respectively. Analytically adjusted ingredient amounts are linked to adult MVMs reported in the NHANES 2003-2008 via the Dietary Supplement Ingredient Database (http://dsid.usda.nih.gov) to facilitate more accurate intake quantification. CONCLUSIONS: Vitamin and mineral overages were measured in adult MVMs, most of which already meet RDAs. Therefore, nutrient overexposures from supplements combined with typical food intake may have unintended health consequences, although this would require further examination.

Interlaboratory Trial for Measurement of Vitamin D and 25-Hydroxyvitamin D [25(OH)D] in Foods and a Dietary Supplement Using Liquid Chromatography-Mass Spectrometry.

Assessment of total vitamin D intake from foods and dietary supplements (DSs) may be incomplete if 25-hydroxyvitamin D [25(OH)D] intake is not included. However, 25(OH)D data for such intake assessments are lacking, no food or DS reference materials (RMs) are available, and comparison of laboratory performance has been needed. The primary goal of this study was to evaluate whether vitamin D3 and 25(OH)D3 concentrations in food and DS materials could be measured with acceptable reproducibility. Five experienced laboratories from the United States and other countries participated, all using liquid chromatography tandem-mass spectrometry but no common analytical protocol; however, various methods were used for determining vitamin D3 in the DS. Five animal-based materials (including three commercially available RMs) and one DS were analyzed. Reproducibility results for the materials were acceptable. Thus, it is possible to obtain consistent results among experienced laboratories for vitamin D3 and 25(OH)D3 in foods and a DS.

Recent and remote memory recalls modulate different sets of stereotypical interlaminar correlations in Arc/Arg3.1 mRNA expression in cortical areas.

Detailed organization of interlaminar relations in neuronal activity underlying recent and remote memory recall is unknown but essential for deciphering interlaminar connections involved in systems-level memory consolidation and permanent information storage. We mapped Arc/Arg3.1 (Arc) mRNA expression, a neuronal activity marker, at multiple rostro-caudal levels of the brain in Wistar rats following a platform search in a water-maze task. Strength of interlaminar correlations in Arc expression and modulation of the strength by memory recall in sensory, motor and association cortical areas were measured at 24h and 1 month in memory retention. In order to estimate the extent of modular organization in neocortical function underlying memory recall, we studied multiple profiles of interlaminar coupling. At the level of cortical areas, we captured two robust stereotypical laminar patterns for distribution of strong and weak interlaminar correlations. These patterns emerged during both control swimming and navigation, at both retention delays. Within limits of these patterns, we established task-, time- and area-dependent modulations of the Arc correlations. Relative to swimming control, during memory recall, changes in strength of analogous interlaminar relations occurred largely in parallel but recent and remote recall modulated mostly distinct correlations. An effective remote memory recall was accompanied by fewer strengthened correlations as compared to recent recall. Thus, a behavioral experience is accompanied by a well-ordered or stereotypical spatial organization of interlaminar relations in neuronal activity distribution. Interlaminar correlations in Arc expression modulated by recent and remote memory recall could guide future inactivation and detection studies necessary to decipher interlaminar connections involved in systems-level consolidation and to reveal mnemonic plasticity specific to spatial memory.

Arc/Arg3.1 mRNA global expression patterns elicited by memory recall in cerebral cortex differ for remote versus recent spatial memories.

The neocortex plays a critical role in the gradual formation and storage of remote declarative memories. Because the circuitry mechanisms of systems-level consolidation are not well understood, the precise cortical sites for memory storage and the nature of enduring memory correlates (mnemonic plasticity) are largely unknown. Detailed maps of neuronal activity underlying recent and remote memory recall highlight brain regions that participate in systems consolidation and constitute putative storage sites, and thus may facilitate detection of mnemonic plasticity. To localize cortical regions involved in the recall of a spatial memory task, we trained rats in a water-maze and then mapped mRNA expression patterns of a neuronal activity marker Arc/Arg3.1 (Arc) upon recall of recent (24 h after training) or remote (1 month after training) memories and compared them with swimming and naive controls. Arc gene expression was significantly more robust 24 h after training compared to 1 month after training. Arc expression diminished in the parietal, cingulate and visual areas, but select segments in the prefrontal, retrosplenial, somatosensory and motor cortical showed similar robust increases in the Arc expression. When Arc expression was compared across select segments of sensory, motor and associative regions within recent and remote memory groups, the overall magnitude and cortical laminar patterns of task-specific Arc expression were similar (stereotypical). Arc mRNA fractions expressed in the upper cortical layers (2/3, 4) increased after both recent and remote recall, while layer 6 fractions decreased only after the recent recall. The data suggest that robust recall of remote memory requires an overall smaller increase in neuronal activity within fewer cortical segments. This activity trend highlights the difficulty in detecting the storage sites and plasticity underlying remote memory. Application of the Arc maps may ameliorate this difficulty.

Topography of Arc/Arg3.1 mRNA expression in the dorsal and ventral hippocampus induced by recent and remote spatial memory recall: dissociation of CA3 and CA1 activation.

The understanding of the mechanisms of memory retrieval and its deficits, and the detection of memory underlying neuronal plasticity, is greatly impeded by a lack of precise knowledge of the brain circuitry that underlies the functions of memory. The specific roles of anatomically distinct hippocampal subdivisions in recent and long-term memory retention and recall are essentially unknown. To address these questions, we mapped the expression of Arc/Arg 3.1 mRNA, a neuronal activity marker, in memory retention at multiple rostrocaudal levels of the dentate gyrus, CA3, CA1, subiculum, and lateral and medial entorhinal cortices after a platform search in a water-maze spatial task at 24 h and 1 month compared with swim and naive controls. We found that the entorhinohippocampal neuronal activity underlying the recall of recent and remote spatial memory has an anatomically distributed and time-dependent organization throughout both the dorsal and ventral hippocampus that is subdivision specific. We found a dissociation in the activity of the entorhinal cortex, CA3, and CA1 over a period of memory consolidation. Although CA3, the dorsal hippocampus, and the entorhinal cortex demonstrated the most persistent learning-specific signal during both recent and long-term memory recall, CA1 and the ventral hippocampus displayed the most dramatic signal decline. We determined the coordinates of activity clusters in the hippocampal subdivisions during the platform search and their dynamics over time. Our mapping data suggest that although the level of corticohippocampal interaction is similar during the retrieval of recent and remote spatial memories, the mnemonic function of the hippocampus may have changed, and the activity underlying remote spatial memory could be anatomically segregated within hippocampal subdivisions in small segments.

Increase of the RNA-binding protein HuD and posttranscriptional up-regulation of the GAP-43 gene during spatial memory.

Neuronal ELAV-like proteins (HuB, HuC, and HuD) are highly conserved RNA-binding proteins able to selectively associate with the 3' UTR of a subset of target mRNAs and increase their cytoplasmic stability and rate of translation. We previously demonstrated the involvement of these proteins in learning, reporting that they undergo a sustained up-regulation in the hippocampus of mice trained in a spatial discrimination task. Here, we extend this finding, showing that a similar up-regulation occurs in the hippocampus of rats trained in another spatial learning paradigm, the Morris water maze. HuD, a strictly neuron-specific ELAV-like protein, is shown to increase after learning, with a preferential binding to the cytoskeletal fraction. HuD up-regulation is associated with an enhancement of GAP-43 mRNA and protein levels, with an apparently increased HuD colocalization with the GAP-43 mRNA and an increased association of neuronal ELAV-like proteins with the GAP-43 mRNA. These learning-dependent biochemical events appear to be spatiotemporally controlled, because they do not occur in another brain region involved in learning, the retrosplenial cortex, and at the level of protein expression they show extinction 1 month after training despite memory retention. By contrast, HuD mRNA levels still remain increased after 1 month in the CA1 region. This persistence may have implications for long-term memory recall.