Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Summary
The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements (ODS), launched the Dietary Supplement Laboratory Quality Assurance Program (DSQAP) to support the measurement needs of the dietary supplements community. The DSQAP has provided an opportunity for dietary supplements testing laboratories to improve comparability of their measurements, as well as for NIST to assess community needs for reference materials, workshops, and other measurement services.
Description
Approximately 75% of the U.S. population takes dietary supplements, including vitamins and mineral supplements, representing an annual expenditure of more than $20 billion. Regulations, driven by reported cases of inaccurate labeling, adulteration, contamination (with pesticides, heavy metals, or toxic botanicals), and drug interactions, are now in place that require manufacturers to evaluate the identity, purity, and composition of their ingredients and finished products. In 2007, a Dietary Supplement Laboratory Quality Assurance Program (DSQAP) was initiated to enable participants to improve the accuracy and precision of their measurements for nutrients, marker compounds, toxic elements, and/or pesticides in dietary supplement ingredients and finished products. From 2017 to 2021, the participants of the DSQAP were served by studies conducted as part of the Health Assessment Measurements QAP. As part of a revamp of the NIST QAPs in 2021, NIST and ODS revitalized the DSQAP, which conducted its sixteenth exercise in 2022. In 2025, the DSQAP Consortium was launched to formalize the collaborative nature of the DSQAP efforts.
Approximately twice a year, exercises have offered participants the opportunity to measure concentrations of nutritional and toxic elements, fat- and water-soluble vitamins, fatty acids, active and/or marker compounds, and contaminants in samples distributed by NIST. Participant data was compiled at NIST and analyzed for accuracy, precision, and concordance within the community. Reports and certificates of completion were sent to participants. Workshops and other presentations offered opportunities to discuss results, measurement challenges, and methodological advancements in the characterization of dietary supplements. The intercomparison exercises, data reports, and workshops were designed to provide participating laboratories with the tools to evaluate their dietary supplement analytical methodology. Information gained through participation has been used by the participants to demonstrate "appropriateness" of analytical methodology to regulatory agencies and to improve the quality of information associated with dietary supplement products through increased measurement capabilities.
Future DSQAP studies will be conducted through the DSQAP Consortium and will be available to Consortium members only.
PRE-CONSORTIUM EXERCISES AND OTHER MAJOR ACCOMPLISHMENTS
Pre-Consortium Exercises
Past participants can access historical results at QAP HUB. Log in using your existing credentials, or enter your email address to request a new password
| Exercise 4 (2025) |
|---|
| Study | Measurands and Samples |
|---|---|
| Nutritional Elements | Ca, Cr, and Se in tablets and gummies |
| Water-Soluble Vitamins | Vitamins B3 and B6 in tablets and gummies |
| Botanicals | Anthocyanidins in bilberry and cranberry extracts |
Samples for Exercise 4 will ship in March 2025.
Dietary supplement related studies from 2017 to 2021 were conducted as part of the Health Assessment Measurements Quality Assurance Program (HAMQAP).
Pre-Consortium Workshops
Supporting The Standardization of Seaweed Measurements Workshop (October 24, 2023): In support of the DSQAP Exercise 1 seaweed collaboration with World Wildlife Fund (WWF), NIST hosted a workshop to discuss the QAP results, observations, and technical recommendations, as well as provide opportunities for discussions on improving measurement capabilities. The workshop included presentations from both NIST staff and external experts, along with discussions between NIST staff and participants for more in-depth conversations. These discussions with the research and analytical laboratory communities included the importance of robust and validated analytical methods and the future role of NIST in supporting seaweed measurement standardization.
NIST DSQAP Workshop (April 23, 2023): NIST and the University of Mississippi National Center for Products Research co-sponsored a half-day workshop that was held in conjunction with the 21st Oxford International Conference on the Science of Botanicals (ICSB). The workshop described recent updates to NIST QAP offerings, and focused on discussion of the analytical challenges in measuring nutrients, phytochemicals, or contaminants in dietary supplements, botanicals, and other natural products.
RELATED REFERENCE MATERIALS
As part of a multi-year interagency agreement among the NIST, the NIH/ODS, the Food and Drug Administration (FDA) Center for Food Safety and Applied Nutrition (CFSAN), and the FDA Center for Drug Evaluation and Research (CDER), NIST is developing Reference Materials (RMs) and Standard Reference Materials (SRMs) for botanical dietary supplements. RMs and SRMs with assigned values for concentrations of active and/or marker compounds, pesticides, and toxic elements are being produced to assist in the verification of manufacturers' label claims and for use in quality control during the manufacturing process in support of the Good Manufacturing Practices released by the FDA in 2007.
For the most up-to-date information about available RMs and SRMs, visit the NIST Store.
Associated Publications
If you or your institution subscribe to a journal cited below, clicking on the link should take you to a page from which you can access the reference.
- Mudge, E.M., Brown, P.N., Rimmer, C.A., Phillips, M.M. (2020) Determination of Curcuminoids in Turmeric Dietary Supplements by HPLC-DAD: Multi-laboratory Study Through the NIH-ODS/NIST Quality Assurance Program, J. AOAC Int. 103(6), 1625-1632.
- Wood, L.J., Lippa, K.A., Phillips, M.M., Rimmer, C.A., Heckert, N.A., Leigh, S.D., Moors, A.J., Pugh, R.S. (2013) Breakfast Cereal Sampling Study for Nutritional Elements, Anal. Bioanal. Chem. 405, 4569-4578.
- Phillips, M.M., Rimmer, C.A., Wood, L.J., Lippa, K.A., Sharpless, K.E., Duewer, D.L., Sander, L.C., Betz, J.M. (2011) Dietary Supplement Laboratory Quality Assurance Program: The First Five Exercises, J. AOAC Int. 94(3), 803-814.