Diseases

Vitamin B 12 Deficiency

A nutritional condition produced by a deficiency of VITAMIN B 12 in the diet, characterized by megaloblastic anemia. Since vitamin B 12 is not present in plants, humans have obtained their supply from animal products, from multivitamin supplements in the form of pills, and as additives to food preparations. A wide variety of neuropsychiatric abnormalities is also seen in vitamin B 12 deficiency and appears to be due to an undefined defect involving myelin synthesis. (From Cecil Textbook of Medicine, 19th ed, p848)

National Library of MedicineMedical Subject Headings2026

Structured Summary

Abstract

A nutritional condition produced by a deficiency of VITAMIN B 12 in the diet, characterized by megaloblastic anemia. Since vitamin B 12 is not present in plants, humans have obtained their supply from animal products, from multivitamin supplements in the form of pills, and as additives to food preparations. A wide variety of neuropsychiatric abnormalities is also seen in vitamin B 12 deficiency and appears to be due to an undefined defect involving myelin synthesis. (From Cecil Textbook of Medicine, 19th ed, p848)

MeSH Record

Classification

Broader headings

Narrower headings

Related Concepts

Knowledge Graph

Loading graph…

Drag nodes to rearrange; hover to trace links; click a node to open its page.

MeSH Record

Synonyms

5 entry terms
  • Deficiency, Vitamin B 12
  • Deficiency, Vitamin B12
  • Vitamin B12 Deficiency
  • Deficiencies, Vitamin B12
  • Vitamin B12 Deficiencies

MeSH Record

Aspects Covered

35 allowable subheadings

Indexed with the subheadings blood, cerebrospinal fluid, chemically induced, classification, complications, congenital, diagnosis, diagnostic imaging, diet therapy, drug therapy, economics, embryology, enzymology, epidemiology, ethnology, etiology, genetics, history, immunology, metabolism, microbiology, mortality, nursing, parasitology, pathology, physiopathology, prevention & control, psychology, radiotherapy, rehabilitation, surgery, therapy, urine, veterinary, virology.

MeSH Record

Indexing Annotation

coord IM with specific B 12 vitamin /defic (IM)

MeSH Hierarchy

Tree Number

  1. C18.654w.521w.500.133w.699.923w

MeSH Record

NLM Classification

QU 194

AMA Style

References

  1. National Library of Medicine. Vitamin B 12 Deficiency. Medical Subject Headings (MeSH). 2026. Unique ID D014806. http://id.nlm.nih.gov/mesh/2026/D014806
  2. Vitamin B 12 Deficiency. In: Wikipedia. https://en.wikipedia.org/wiki/Vitamin_B12_deficiency
  3. Vitamin B 12 Deficiency. In: Wikidata. https://www.wikidata.org/wiki/Q3234995