ArticleThe American journal of clinical nutrition2011
Monitoring of vitamin B-12 nutritional status in the United States by using plasma methylmalonic acid and serum vitamin B-12.
Article in The American journal of clinical nutrition, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 72 papers, 3 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
72 citing papers in PubMed, 3 syntheses or guidelines pooled it, 151 citations in OpenAlex.
- Vitamin B12 Deficiency in Sickle Cell Disease: Method-Driven Estimates and Systematic Diagnostic Misclassification.European journal of haematology · 2026Pooled it
- Association Between Methylmalonic Acid and Cognition: A Systematic Review and Meta-Analysis.Frontiers in pediatrics · 2022Pooled it
- Pooled it
- Trial
- The Diagnostic Accuracy of Methylmalonic Acid to Detect Inadequate Vitamin B-12 Status Relative to 3cB-12 Was Higher Compared with That of Total Cobalamin and Total Homocysteine in a Cross-Sectional Survey of Apparently Healthy US Adults.Current developments in nutrition · 2026Article
- Pilot Newborn Screening for Vitamin B12 Deficiency in the Czech Republic: Results and Detailed Studies on Identified Babies and Their Mothers.International journal of neonatal screening · 2026Article
- Vitamin B12 Status and Cardiovascular Risk: Novel Insights from NMR-Based Lipoprotein Profiling in 20,665 Adults.Journal of clinical medicine · 2026Article
- Article
- Vitamin BClinical nutrition ESPEN · 2025Observational
- Estimating effects of serum vitamin B12 levels on psychiatric disorders and cognitive impairment: a Mendelian randomization study.Communications medicine · 2025Article
- Nutritional Support of Chronic Obstructive Pulmonary Disease.Nutrients · 2025Review
- Lifestyle Interventions in Frailty.Advances in experimental medicine and biology · 2025Review
- Vitamin BInternational journal of molecular sciences · 2024Review
- Associations of methylmalonic acid and depressive symptoms with mortality: a population-based study.Translational psychiatry · 2024Article
- Increased serum methylmalonic acid levels were associated with the presence of cognitive dysfunction in older chronic kidney disease patients with albuminuria.BMC geriatrics · 2024Article
- Folate, vitamin B12, and homocysteine status in the Korean population: data from the 2013-2015 Korea National Health and Nutrition Examination Survey.Epidemiology and health · 2024Article
- Assessing Nutritional Anemia Among University Students in Jazan, Saudi Arabia: A Public Health Perspective.Journal of blood medicine · 2024Article
- Pulmonary fungal infection in a neonate with methylmalonic acidemia: A case report.World journal of clinical cases · 2023Article
- Article
- Review
12 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors at 1 institution in 1 country.
Funding
Abstract
backgroundVarious definitions, criteria, tests, and cutoffs have been used to define vitamin B-12 status; however, a need exists for the systematic study of vitamin B-12 status in the United States because of concerns about high folic acid intakes and the potential for associated adverse effects.
objectiveThe objective was to determine the effect of different cutoff choices on outcomes and of the different degrees of serum vitamin B-12 status, definable by the concurrent use of a functional and circulating marker as the first steps to developing a data-based consensus on the biochemical diagnosis of vitamin B-12 deficiency.
designData from NHANES, a nationally representative cross-sectional survey, were examined for adults aged >19 y (mean ± SD age: 45 ± 1 y) from 1999 to 2004 (n = 12,612).
resultsCommonly used cutoffs had a greater effect on prevalence estimates of low vitamin B-12 status with the use of vitamin B-12 than with the use of methylmalonic acid (MMA; 3-26% and 2-6%, respectively). A cutoff of >148 pmol/L for vitamin B-12 and of ≤210 nmol/L for MMA resulted in significant misclassifications. Approximately 1% of adults had a clear vitamin B-12 deficiency (low vitamin B-12 and elevated MMA); 92% of adults had adequate vitamin B-12 status. A high percentage of younger women characterized the group with low vitamin B-12 and normal MMA (2% of adults) and may have falsely reflected low vitamin B-12. Adults with elevated MMA (5%) only were demographically similar (ie, by age and race) to the deficient group and may have included some individuals with early vitamin B-12 deficiency.
conclusionsThese analyses indicate the challenges of assessing vitamin B-12 status when uncertainties exist about the appropriate cutoffs. Future studies should determine definable endpoints to achieve this goal.
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Registered trials
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