Revised BC Guideline: Cobalamin (Vitamin B12) and Folate Deficiency

The Cobalamin (Vitamin B12) and Folate Deficiency guideline (effective 18 January 2023) covers the primary care investigation and management of cobalamin (vitamin B12 or simply B12) and folate deficiency in adults. This guideline outlines the indications for B12 testing and discusses an observed increase in B12 testing in BC.


  • Outpatient and inpatient laboratory test volumes for B12 investigations increased from 267 721 to 570 265 between 2013 and 2020. This resulted in an increase in annual B12 testing expenditure from $3 million to $5.6 million during the same time period.
  • On average, 420 303 tests cost $4.4 million per year.
  • Patients ≥ 65 years of age accounted for the majority (37%) of B12 test volumes in 2019.
  • Female patients account for 62% of annual test volumes while males account for 38%.

Key recommendations include:

  • Routine B12 screening and testing in asymptomatic patients is not supported by evidence.
  • Consider B12 supplementation without testing in asymptomatic patients with risk factors for B12 deficiency. Patients can call 8-1-1 to speak with a HealthLink BC registered dietitian.
  • B12 deficiency can cause preventable permanent injury and should be considered with new onset neurological conditions and symptoms suggestive of B12 deficiency.
  • Folate testing is rarely indicated but may be available via consultation with the laboratory medicine physician or scientist.
  • Folate deficiency in pregnancy is associated with preventable and serious fetal harm (i.e., neural tube defects). Folic acid supplementation is recommended during pregnancy.
  • A daily multivitamin containing B12 and folic acid is recommended for all people who could become pregnant, especially those with a vegan diet.


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Martin Dawes, MD, Janet Evans, MD, Dan Holmes, MD, Andre Mattman, MD, Doug McTaggart, MD, Parin Patel, MD, Hetesh Ranchod, MD, Chase Simms, MPH. Revised BC Guideline: Cobalamin (Vitamin B12) and Folate Deficiency . BCMJ, Vol. 65, No. 4, May, 2023, Page(s) - News.

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