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Serum 25-hydroxyvitamin D status of the US population: 1988–1994 compared with 2000–2004

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Looker, Anne C, Pfeiffer, Christine M, Lacher, David A, Schleicher, Rosemary L, Picciano, Mary Frances, Yetley, Elizabeth A·2008·The American Journal of Clinical Nutrition

Abstract

Background Changes in serum 25-hydroxyvitamin D (25OHD) concentrations in the US population have not been described. Objective Use data from the National Health and Nutrition Examination Surveys (NHANES) to compare serum 25OHD concentrations in the US population in 2000–2004 versus 1988–1994, and to identify contributing factors. Design Serum 25OHD was measured with a radioimmunoassay kit in 20,289 participants in NHANES 2000–2004 and 18,158 participants in NHANES III (1988–1994). Body mass index (BMI) was calculated from measured height and weight. Milk intake and sun protection were assessed by questionnaire. Assay differences were assessed by re-analyzing 150 stored sera specimens from NHANES III with the current assay. Results Age-adjusted mean serum 25OHD concentrations were significantly lower by 5–20 nmol/L in NHANES 2000–2004 than in NHANES III. After accounting for assay shifts, age-adjusted means in NHANES 2000–2004 remained significantly lower (by 5–9 nmol/L) in most males, but not in most females. In a study subsample, accounting for the confounding effects of assay differences changed mean serum 25OHD by ~10 nmol/L, while accounting for changes in the factors likely related to real changes in vitamin D status (BMI, milk intake, and sun protection) changed means by 1–1.6 nmol/L. Conclusions Overall, mean serum 25OHD was lower in 2000–2004 than 1988–1994. Assay changes unrelated to changes in vitamin D status accounted for much of the difference in most population groups. In an adult subgroup, combined changes in BMI, milk intake and sun protection appeared to contribute to a real decline in vitamin D status.

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Metadata

Authors
Looker, A. C., Pfeiffer, C. M., Lacher, D. A., Schleicher, R. L., Picciano, M. F., & Yetley, E. A.
Venue
The American Journal of Clinical Nutrition
Publisher
Elsevier BV
Published
2008-12
Volume
88
Issue
6
Pages
1519-1527
ISSN
0002-9165 (ISSN-L)
OpenAlex
W2019558876
Cited by
621
References
19
FWCI
38.34
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Serum 25-hydroxyvitamin D status of the US population: 1988–1994 compared with 2000–2004. https://app.cochat.ai/papers/10.3945/ajcn.2008.26182
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Looker, A. C., Pfeiffer, C. M., Lacher, D. A., Schleicher, R. L., Picciano, M. F., & Yetley, E. A. (2008). Serum 25-hydroxyvitamin D status of the US population: 1988–1994 compared with 2000–2004. The American Journal of Clinical Nutrition. https://doi.org/10.3945/ajcn.2008.26182

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