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NIST Quality Assurance Program for Dietary Supplement Measurements Open for Registration

Registration closes on March 4, 2022.

Dietary Supplement Quality Assurance Program Exercise 1

NIST has revitalized the Dietary Supplement Laboratory Quality Assurance Program (DSQAP) to support the measurement needs of the dietary supplement testing community.  Laboratories can use this program to assess their in-house methods, and participation in a quality assurance program in conjunction with the use of reference materials has been shown to improve the comparability and precision of measurements over time. NIST also uses the results from QAP exercises to assess the need and suitability of potential reference materials and provide educational resources through reports, presentations, and workshops.

  • More details about Exercise 1 can be found in the invitation letter.

  • Registration for Exercise 1 will close on March 4, 2022.

  • Samples will be distributed in late March/early April 2022.

  • Please qaphub [at] (contact us) with questions.

The accuracy and precision of measurements made by dietary supplement testing labs is important so that manufacturers and consumers are confident in the claims on ingredients labels, product safety, and to comply with regulations from the US Food and Drug Administration and international bodies.

For many decades, NIST has supported these communities with reference materials that labs can use to check their analytical methods for measurements of dietary supplement ingredients and finished products. This program is another form of measurement support.

Labs can choose to participate in a variety of DSQAP studies, including nutritional and toxic elements, fat- and water-soluble vitamins, other chemical contaminants, and active and/or marker compounds.  DSQAP participants are not required to select all analytes or all materials for measurement, but can choose as many analytes as are applicable to the work conducted in their lab.

Participants in NIST quality assurance programs analyze the materials and share their results with NIST. In return, labs learn how their measurement results compare to other participants in the study, and to the rigorously measured and agreed upon value, when available.  Each participant is provided with a certificate of participation, which they can use to show due diligence in establishing scientifically valid methods within their lab.  A final report, in which participating labs’ identities remain confidential, is made public.  To follow up, workshops and webinars are held to discuss results as well as methodological advancements in food nutrition and safety measurements.  NIST will also use the results to develop new reference materials and measurement science education targeted at the communities’ needs.

Registration for Exercise 1 is now open, and will feature studies on nutritional and toxic elements, water- and fat-soluble vitamins phenolic content, proximates, dietary fiber, starch, and withanolides in a variety of dietary supplement ingredients and finished products.

Exercise 1 will also highlight the compositional testing of kelp materials, sponsored by the World Wildlife Fund.  Several studies will feature kelp samples in order to identify any measurement challenges across the seaweed and kelp farming industry, narrow focus to the methodologies that need improved standardization, and connect the farming industry with the analytical testing community.  In addition to a final report and participation certificates, additional educational resources (e.g. workshops) will be developed to discuss findings and provide networking opportunities.

Exercise 1 Study


Nutritional and Toxic Elements:  Ca, Cr, I, K, Mg, Na, S, Se, tAs/iAs, Cd, Pb, Hg, Cu, Zn


Water- and Fat-Soluble Vitamins:  Vitamin B3, Vitamin K1


Total Phenolic Content:   Gallic acid, gallic acid equivalents

multi-laboratory validation of AOAC Official First Action Method 2017.13

Kelp and Green Tea

Proximates, Fiber, and Starch:   ash, protein, carbohydrates, fat (crude fat and fatty acids), calories, solids, dietary fiber, starch


Contaminants:  PFAS


B Vitamins:   thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), vitamin B6, biotin (B7),

folic acid (B9), vitamin B12

Liquid and Powdered Meal Replacement Formulations

Withanolides:   withanoside IV, withanoside V, withaferin A, 12-deoxywithastromonolide, withanolide A, withanolide B

multi-laboratory validation of a AOAC Official First Action Method 2015.17



Released January 21, 2022, Updated January 24, 2022