Abstract | BACKGROUND:
Vitamin C ( ascorbic acid) may be the most important water-soluble antioxidant in human plasma. In the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994), approximately 13% of the US population was vitamin C deficient (serum concentrations <11.4 micromol/L). OBJECTIVE: The aim was to determine the most current distribution of serum vitamin C concentrations in the United States and the prevalence of deficiency in selected subgroups. DESIGN: Serum concentrations of total vitamin C were measured in 7277 noninstitutionalized civilians aged > or =6 y during the cross-sectional, nationally representative NHANES 2003-2004. The prevalence of deficiency was compared with results from NHANES III. RESULTS: The overall age-adjusted mean from the square-root transformed (SM) concentration was 51.4 micromol/L (95% CI: 48.4, 54.6). The highest concentrations were found in children and older persons. Within each race-ethnic group, women had higher concentrations than did men (P < 0.05). Mean concentrations of adult smokers were one-third lower than those of nonsmokers (SM: 35.2 compared with 50.7 micromol/L and 38.6 compared with 58.0 micromol/L in men and women, respectively). The overall prevalence (+/-SE) of age-adjusted vitamin C deficiency was 7.1 +/- 0.9%. Mean vitamin C concentrations increased (P < 0.05) and the prevalence of vitamin C deficiency decreased (P < 0.01) with increasing socioeconomic status. Recent vitamin C supplement use or adequate dietary intake decreased the risk of vitamin C deficiency (P < 0.05). CONCLUSIONS: In NHANES 2003-2004, vitamin C status improved, and the prevalence of vitamin C deficiency was significantly lower than that during NHANES III, but smokers and low-income persons were among those at increased risk of deficiency.
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Authors | Rosemary L Schleicher, Margaret D Carroll, Earl S Ford, David A Lacher |
Journal | The American journal of clinical nutrition
(Am J Clin Nutr)
Vol. 90
Issue 5
Pg. 1252-63
(Nov 2009)
ISSN: 1938-3207 [Electronic] United States |
PMID | 19675106
(Publication Type: Journal Article)
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Chemical References |
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Topics |
- Adolescent
- Adult
- Ascorbic Acid
(blood)
- Ascorbic Acid Deficiency
(epidemiology)
- Body Mass Index
- Child
- Cross-Sectional Studies
- Diet
- Dietary Supplements
- Ethnicity
(statistics & numerical data)
- Female
- Humans
- Interviews as Topic
- Male
- Nutrition Surveys
- Poverty
(statistics & numerical data)
- Probability
- Smoking
(adverse effects)
- Socioeconomic Factors
- United States
(epidemiology)
- Young Adult
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