Pamela R. Pehrsson

Including Food 25-Hydroxyvitamin D in Intake Estimates May Reduce the Discrepancy between Dietary and Serum Measures of Vitamin D Status

The discrepancy between the commonly used vitamin D status measures-intake and serum 25-hydroxyvitamin D [25(OH)D] concentrations--has been perplexing. Sun exposure increases serum 25(OH)D concentrations and is often used as an explanation for the higher population-based serum concentrations in the face of apparently low vitamin D intake. However, sun exposure may not be the total explanation. 25(OH)D, a metabolite of vitamin D, is known to be present in animal-based foods. It has been measured and reported only sporadically and is not currently factored into U.S. estimates of vitamin D intake. Previously unavailable preliminary USDA data specifying the 25(OH)D content of a subset of foods allowed exploration of the potential change in the reported overall vitamin D content of foods when the presence of 25(OH)D was included. The issue of 25(OH)D potency was addressed, and available commodity intake estimates were used to outline trends in projected vitamin D intake when 25(OH)D in foods was taken into account. Given the data available, there were notable increases in the total vitamin D content of a number of animal-based foods when potency-adjusted 25(OH)D was included, and in turn there was a potentially meaningful increase (1.7-2.9 μg or 15-30% of average requirement) in vitamin D intake estimates. The apparent increase could reduce discrepancies between intake estimates and serum 25(OH)D concentrations. The relevance to dietary interventions is discussed, and the need for continued exploration regarding 25(OH)D measurement is highlighted.

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.

Iodine in food- and dietary supplement–composition databases

The US Food and Drug Administration (FDA) and the Nutrient Data Laboratory (NDL) of the USDA 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 article is to describe the harmonization plan and the results of initial iodine analyses accomplished under that plan. For many years, the FDAs Total Diet Study (TDS) has measured iodine concentrations in selected foods collected in 4 regions of the country each year. For more than 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. The NDL recently qualified a commercial laboratory to conduct iodine analysis of foods by 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 by the FDA laboratory using its standard colorimetric method yielded comparable results. The 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. The FDA and the 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 foods in the US population. In addition, the NDL continues to analyze dietary supplements for iodine and, in collaboration with the NIH Office of Dietary Supplements, to publish the data online in the Dietary Supplement Ingredient Database. The goal is to provide, through these 2 harmonized databases and the continuing TDS focus on iodine, improved tools for estimating iodine intake in population studies.

USDA’s National Food and Nutrient Analysis Program (NFNAP) produces high-quality data for USDA food composition databases: Two decades of collaboration

For nearly 20years, the National Food and Nutrient Analysis Program (NFNAP) has expanded and improved the quantity and quality of data in US Department of Agricultures (USDA) food composition databases (FCDB) through the collection and analysis of nationally representative food samples. NFNAP employs statistically valid sampling plans, the Key Foods approach to identify and prioritize foods and nutrients, comprehensive quality control protocols, and analytical oversight to generate new and updated analytical data for food components. NFNAP has allowed the Nutrient Data Laboratory to keep up with the dynamic US food supply and emerging scientific research. Recently generated results for nationally representative food samples show marked changes compared to previous database values for selected nutrients. Monitoring changes in the composition of foods is critical in keeping FCDB up-to-date, so that they remain a vital tool in assessing the nutrient intake of national populations, as well as for providing dietary advice.

Sodium Intake among US School-Aged Children: National Health and Nutrition Examination Survey, 2011-2012

BACKGROUND Identifying current major dietary sources of sodium can enhance strategies to reduce excess sodium intake, which occurs among 90% of US school-aged children. OBJECTIVE To describe major food sources, places obtained, and eating occasions contributing to sodium intake among US school-aged children. DESIGN Cross-sectional analysis of data from the 2011-2012 National Health and Nutrition Examination Survey. PARTICIPANTS/SETTING A nationally representative sample of 2,142 US children aged 6 to 18 years who completed a 24-hour dietary recall. MAIN OUTCOME MEASURES Population proportions of sodium intake from major food categories, places, and eating occasions. STATISTICAL ANALYSES PERFORMED Statistical analyses accounted for the complex survey design and sampling. Wald F tests and t tests were used to examine differences between subgroups. RESULTS Average daily sodium intake was highest among adolescents aged 14 to 18 years (3,565±120 mg), lowest among girls (2,919±74 mg). Little variation was seen in average intakes or the top five sodium contributors by sociodemographic characteristics or weight status. Ten food categories contributed to almost half (48%) of US school-aged childrens sodium intake, and included pizza, Mexican-mixed dishes, sandwiches, breads, cold cuts, soups, savory snacks, cheese, plain milk, and poultry. More than 80 food categories contributed to the other half of childrens sodium intake. Foods obtained from stores contributed 58% of sodium intake, fast-food/pizza restaurants contributed 16%, and school cafeterias contributed 10%. Thirty-nine percent of sodium intake was consumed at dinner, 31% at lunch, 16% from snacks, and 14% at breakfast. CONCLUSIONS With the exception of plain milk, which naturally contains sodium, the top 10 food categories contributing to US schoolchildrens sodium intake during 2011-2012 comprised foods in which sodium is added during processing or preparation. Sodium is consumed throughout the day from multiple foods and locations, highlighting the importance of sodium reduction across the US food supply.

Top sources of dietary sodium from birth to age 24 mo, United States, 2003–2010

BACKGROUND Sodium intake is high in US children. Data are limited on the dietary sources of sodium, especially from birth to age 24 mo. OBJECTIVE We identified top sources of dietary sodium in US children from birth to age 24 mo. DESIGN Data from the NHANES 2003-2010 were used to examine food sources of sodium (population proportions and mean intakes) in 778 participants aged 0-5.9 mo, 914 participants aged 6-11.9 mo, and 1219 participants aged 12-23.9 mo by sociodemographic characteristics. RESULTS Overall, mean dietary sodium intake was low in 0-5.9-mo-old children, and the top contributors were formula (71.7%), human milk (22.9%), and commercial baby foods (2.2%). In infants aged 6-11.9 mo, the top 5 contributors were formula (26.7%), commercial baby foods (8.8%), soups (6.1%), pasta mixed dishes (4.0%), and human milk (3.9%). In children aged 12-23.9 mo, the top contributors were milk (12.2%), soups (5.4%), cheese (5.2%), pasta mixed dishes (5.1%), and frankfurters and sausages (4.6%). Despite significant variation in top food categories across racial/ethnic groups, commercial baby foods were a top food contributor in children aged 6-11.9 mo, and frankfurters and sausages were a top food contributor in children aged 12-23.9 mo. The top 5 food categories that contributed to sodium intake also differed by sex. Most of the sodium consumed (83-90%) came from store foods (e.g., from the supermarket). In children aged 12-23.9 mo, 9% of sodium consumed came from restaurant foods, and 4% of sodium came from childcare center foods. CONCLUSIONS The vast majority of sodium consumed comes from foods other than infant formula or human milk after the age of 6 mo. Although the majority of sodium intake was from store foods, after age 12 mo, restaurant foods contribute significantly to intake. Reducing the sodium content in these settings would reduce sodium intake in the youngest consumers.

A Free New Dietary Supplement Label Database for Registered Dietitian Nutritionists

The Academy of Nutrition and Dietetics recognizes the importance of including dietary supplements in assessing and planning dietary intakes.1 Dietary supplement (DS) use in the United States has increased markedly during the last 30 years and is now widespread across all segments of society.2,3,4,5,6 Today, over half of adults and a third of US children have used one or more DS within the past 30 days, with multi-vitamin, multi-mineral (MVMM) products especially common.7, 8 Since supplements are now major sources of several nutrients such as calcium and vitamin D in American diets, it is important for registered dietitians and nutritionists (RDNs) to include their contributions when assessing intakes or planning diets.9,10,11 Likewise, for national nutrition surveillance the contributions to nutrient intakes from supplements must be considered in order to identify groups at dietary risk because their intakes fall below the estimated average requirement (EAR) or above the upper tolerable intake level (UL).12 For example, when supplements are included in assessments, the proportion of the United States population that is below the EAR is much less for several vitamins11 and fewer women are “at risk” (defined as below the EAR) for folate intake than when they are not.13,14 For some nutrients, like folic acid, the UL is established based solely for the form that comes from fortificants in foods and in dietary supplements. RDNs, epidemiologists, and public health officials also need accurate dietary supplement databases in order to evaluate possible associations between nutrient intake and disease outcomes. The National Health and Nutrition Examination Survey (NHANES) dietary supplement label database contains label-derived information from supplement products that is updated every two years. Information contained in the database is driven by what is reported by survey participants. The currently available database contains supplement label information for products reported from 1999–2010. While the NHANES DS database provides useful information, it is not comprehensive and is more likely to contain commonly used supplements and less likely to contain infrequently used supplements.15 In fact, MVMM products account for only about half of all supplements used.3 Additionally, not all information from the label is recorded and released in the database. For example, the NHANES database does not contain information such as health claims, other ingredients and warning statements that may have been on the label.

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.

Feasibility of Including Green Tea Products for an Analytically Verified Dietary Supplement Database

The Dietary Supplement Ingredient Database (DSID) is a federally funded, publicly accessible dietary supplement database that currently contains analytically derived information on micronutrients in selected adult and childrens multivitamin and mineral (MVM) supplements. Other constituents in dietary supplement products such as botanicals are also of interest and thus are being considered for inclusion in the DSID. Thirty-eight constituents, mainly botanicals were identified and prioritized by a federal interagency committee. Green tea was selected from this list as the botanical for expansion of the DSID. This article describes the process for prioritizing dietary ingredients in the DSID. It also discusses the criteria for inclusion of these ingredients, and the approach for selecting and testing products for the green tea pilot study.

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.