What the research examined
Clinical reviews describe vitamin B12's role in cellular metabolism and the diverse causes and manifestations of deficiency. They discuss transport, cellular uptake, and biomarkers, including homocysteine and methylmalonic acid. Deficiency-related observations are a distinct research question from effects in populations with adequate B12 status.
How to interpret the findings
B12 is a vitamin rather than a peptide. These reviews provide biological context; evidence about correcting deficiency does not establish additional benefits in nondeficient populations.
Research literature
- Vitamin B12 deficiency.
Nature reviews. Disease primers · 2017 · PMID 28660890 - Clinical practice. Vitamin B12 deficiency.
The New England journal of medicine · 2013 · PMID 23301732
Links open the indexed paper records. Summaries are based on those records and their available abstracts, not a systematic review or a full-text appraisal of every study.