2013 Annual Report
Objective 1: Determine and monitor the nutrient and other ingredient composition of dietary supplements commonly consumed by Americans. Compile, maintain, and disseminate electronic dietary supplement composition databases utilizing standardized approaches according to specified timelines.
Objective 2: Evaluate and update methods for the acquisition, evaluation, compilation and dissemination of dietary supplement composition data utilizing new, robust computerized systems.
Objective 3: Investigate the variability of dietary supplement composition data attributable to inherent supplement differences, analytical methodology, and other contributing factors.
Objective 2: NDL will develop and validate methods for data acquisition (e.g., USDA analytical data, industry data), including statistical sampling, sample handling, laboratory methodology, and data quality evaluation, to ensure representative and accurate dietary supplement ingredient estimates. For analytical studies managed by NDL, statistical sampling plans for the analysis of dietary supplements will continue to be developed based upon market share and ingredient label information. NDL will include available Standard Reference Materials (SRMs) when sending batches of samples to the laboratory for analysis. NIST recommendations for the analysis of ingredients in SRMs, including stability information and extraction and homogenization procedures will be used in the development and evaluation of NDL laboratory protocols for contracted labs.
Objective 3: NDL will investigate the variability of dietary supplement composition data attributable to inherent supplement differences, analytical methodology, and other contributing factors. The magnitude of variability attributable to the measurement process will vary for each ingredient or ingredient group (i.e., minerals analyzed by inductively-coupled plasma spectroscopy (ICP)) and can confound the results for variability inherent in a product. In addition, the assessment of individual ingredient variability will be a factor in determining sample sizes for future analytical studies.
DSID-1 was released in 2009 with national estimates for vitamins and minerals in adult multivitamin/mineral (MVM) products. DSID-2 was released in April 2012 with national estimates for ingredients in children’s MVM supplement products and updated values for the adult MVM data. DSID-3, expected to be released in April 2014, will provide vitamin and mineral data for over-the-counter (OTC) prenatal MVMs and results for the three major omega-3 fatty acids in omega-3 fatty acid dietary supplements. The release also includes DSID codes linked to National Health and Nutrition Examination Survey (NHANES) dietary supplement data and 3 MVM calculators that can be used to apply the regression results to additional ingredient levels for each product category.
National studies are underway analyzing ingredients in over-the-counter prenatal MVMs, omega-3 fatty acid supplements and again in adult MVMs, the most common dietary supplement used in the U.S. Statistical sampling plans were developed for all national studies, identifying market channel distributions and representative products. An average of 3 lots per product was purchased nationwide. Supplements were sent to qualified laboratories and analyzed using validated methods.