Evidence map›Paper›PMID 32844171›Full record

Trial reportThe American journal of clinical nutrition2020

Measuring vitamin B-12 bioavailability with [13C]-cyanocobalamin in humans.

Sarita Devi, Roshni M Pasanna, Zeeshan Shamshuddin, Kishor Bhat, Ambily Sivadas, Amit K Mandal, Anura V Kurpad

Open access · bronzeAbstract readClinical Trial
PubMed Publisher
In one paragraph

Trial report in The American journal of clinical nutrition, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
13citing papers in PubMed, 2 pooled it
3.0field-weighted citation impact, top 8% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

13 citing papers in PubMed, 2 syntheses or guidelines pooled it, 37 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
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  13. Assessing vitamin B-12 absorption and bioavailability: read the label.The American journal of clinical nutrition · 2020
    Article
4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

7 authors at 1 institution in 1 country.

Sarita DeviDivision of Nutrition, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
Roshni M PasannaDivision of Nutrition, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
Zeeshan ShamshuddinDivision of Nutrition, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
Kishor BhatDivision of Nutrition, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
Ambily SivadasDivision of Nutrition, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
Amit K MandalDivision of Clinical Proteomics, St. John's Research Institute, St. John's National Academy of Health Sciences, Bangalore, India.
Anura V KurpadDepartment of Physiology, St. John's Medical College, St. John's National Academy of Health Sciences, Bangalore, India.
St. John's National Academy of Health Sciences · IN

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundVitamin B-12 deficiency is widespread in many parts of the world, affecting all age groups and increasing with age. It is primarily due to a low intake of animal source foods or malabsorption. The measurement of bioavailability of vitamin B-12 is etiologically important in deficiency but is limited due to the use of radioactive isotopes like [57Co]- or [14C]-cyanocobalamin.

objectivesThe aim of this study was to measure the bioavailability of [13C]-cyanocobalamin in humans and to assess the effect of parenteral replenishment of vitamin B-12 on the bioavailability.

methodsWe synthesized a stable isotope-labeled vitamin B-12, [13C]-cyanocobalamin, using Salmonella enterica by providing [13C2]-ethanolamine as a sole carbon source. After purification and mass spectrometry-based characterization, its oral bioavailability was measured in the fasted state with high and low oral doses, before and after parenteral replenishment of vitamin B-12 stores, from the kinetics of its plasma appearance in a 2-compartment model.

results[13C]-cyanocobalamin was completely decyanated to [13C]-methylcobalamin describing metabolic utilization, and its plasma appearance showed early and late absorption phases. At a low dose of 2.3 µg, the mean bioavailability was 46.2 ± 12.8 (%, mean ± SD, n = 11). At a higher dose of 18.3 µg, the mean bioavailability was 7.6 ± 1.7 (%, mean ± SD, n = 4). Parenteral replenishment of the vitamin B-12 store in deficient individuals prior to the measurement resulted in a 1.9-fold increase in bioavailability.

conclusionsVitamin B-12 bioavailability is dose dependent and at a low dose that approximates the normal daily requirement (46%). The stable isotope method described here could be used to define the etiology of deficiency and to inform the dietary requirement in different physiologic states as well as the dose required for supplementation and food fortification. This trial was registered at the Clinical Trials Registry of India as CTRI/2018/04/012957.

Indexed as

Carbon IsotopesAdultBiological AvailabilityFemaleHumansIsotope LabelingMaleModels, BiologicalVitamin B 12Young AdultCarbon IsotopesVitamin B 12bioavailabilitybiosynthesiscyanocobalaminhumanmass spectrometrymethylcobalaminpharmacokineticsstable isotopevitamin B-12

Identifiers

PMID32844171
OpenAlexW3081350253

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.