Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2011 Jul;94(1):303S-312S.
doi: 10.3945/ajcn.111.013011. Epub 2011 May 18.

Biomarkers of folate status in NHANES: a roundtable summary

Elizabeth A Yetley  1 , Christine M Pfeiffer, Karen W Phinney, Zia Fazili, David A Lacher, Regan L Bailey, Sheena Blackmore, Jay L Bock, Lawrence C Brody, Ralph Carmel, L Randy Curtin, Ramón A Durazo-Arvizu, John H Eckfeldt, Ralph Green, Jesse F Gregory 3rd, Andrew N Hoofnagle, Donald W Jacobsen, Paul F Jacques, Anne M Molloy, Joseph Massaro, James L Mills, Ebba Nexo, Jeanne I Rader, Jacob Selhub, Christopher Sempos, Barry Shane, Sally Stabler, Patrick Stover, Tsunenobu Tamura, Alison Tedstone, Susan J Thorpe, Paul M Coates, Clifford L Johnson, Mary Frances Picciano
Affiliations
Review

Biomarkers of folate status in NHANES: a roundtable summary

Elizabeth A Yetley et al. Am J Clin Nutr. 2011 Jul.

Abstract

A roundtable to discuss the measurement of folate status biomarkers in NHANES took place in July 2010. NHANES has measured serum folate since 1974 and red blood cell (RBC) folate since 1978 with the use of several different measurement procedures. Data on serum 5-methyltetrahydrofolate (5MTHF) and folic acid (FA) concentrations in persons aged ≥60 y are available in NHANES 1999-2002. The roundtable reviewed data that showed that folate concentrations from the Bio-Rad Quantaphase II procedure (Bio-Rad Laboratories, Hercules, CA; used in NHANES 1991-1994 and NHANES 1999-2006) were, on average, 29% lower for serum and 45% lower for RBC than were those from the microbiological assay (MA), which was used in NHANES 2007-2010. Roundtable experts agreed that these differences required a data adjustment for time-trend analyses. The roundtable reviewed the possible use of an isotope-dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) measurement procedure for future NHANES and agreed that the close agreement between the MA and LC-MS/MS results for serum folate supported conversion to the LC-MS/MS procedure. However, for RBC folate, the MA gave 25% higher concentrations than did the LC-MS/MS procedure. The roundtable agreed that the use of the LC-MS/MS procedure to measure RBC folate is premature at this time. The roundtable reviewed the reference materials available or under development at the National Institute of Standards and Technology and recognized the challenges related to, and the scientific need for, these materials. They noted the need for a commutability study for the available reference materials for serum 5MTHF and FA.

PubMed Disclaimer

Figures

FIGURE 1.
FIGURE 1.
Performance of the National Center for Environmental Health, Centers for Disease Control and Prevention, liquid chromatography-tandem mass spectrometry measurement procedure over multiple years with the use of the National Institute of Standards and Technology standard reference material (SRM) 1955 (28). Dotted lines represent the target concentrations for SRM levels 1, 2, and 3. Solid lines track the performance of the measurement procedure for each SRM level between 2004 and 2010. 5MTHF, serum 5-methyltetrahydrofolate.
FIGURE 2.
FIGURE 2.
Performance of the National Center for Environmental Health, Centers for Disease Control and Prevention, liquid chromatography–tandem mass spectrometry measurement procedure over multiple years with the use of the National Institute for Biological Standards and Control reference material 03/178 (29). Dotted lines represent the target concentrations for total folate, 5-methyltetrahydrofolate (5MTHF), folic acid (FA), and 5-formyltetrahydrofolic acid (5FTHF) in this reference material. Solid lines track the performance of the measurement procedure for each folate species and the total folate between 2005 and 2010 (CM Pfeiffer, unpublished observations, 2011).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Yetley EA, Johnson CL. Folate and vitamin B-12 biomarkers in NHANES: history of their measurement and use. Am J Clin Nutr 2011;94(suppl):322S–31S - PMC - PubMed
    1. Senti FR, Pilch SM. Analysis of folate data from the second National Health and Nutrition Examination Survey (NHANES II). J Nutr 1985;115:1398–402 - PubMed
    1. Raiten DJ, Fisher KD. Assessment of folate methodology used in the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). J Nutr 1995;125:1371S–98S - PubMed
    1. Yetley EA, Rader JI. Modeling the level of fortification and post-fortification assessments: U.S. experience. Nutr Rev 2004;62:S50–9 - PubMed
    1. Pfeiffer CM, Johnson CL, Jain RB, et al. Trends in blood folate and vitamin B-12 concentrations in the United States, 1988-2004. Am J Clin Nutr 2007;86:718–27 - PubMed

Publication types