Vitamin B12 (Cobalamin)

Vitamin B12 (Cobalamin) – Essential for Energy, Nerve Health & Red Blood Cell Production

Vitamin B12 is a vital nutrient that supports energy metabolism, neurological function, and healthy red blood cell formation. This evidence-based guide explains how B12 works, why it matters, and how IV therapy can optimise its absorption.

What the ingredient is

Vitamin B12, or cobalamin, is a water-soluble B-vitamin essential for neurological function, DNA synthesis, and cellular energy production. It has a complex structure containing cobalt at its centre and is exclusively found in animal-derived foods.

Mechanism of action

Vitamin B12 acts as a coenzyme in critical metabolic pathways, particularly in the conversion of homocysteine to methionine and the production of succinyl-CoA in the Krebs cycle. These reactions are essential for energy generation, nerve cell maintenance, and red blood cell formation. IV administration bypasses gastrointestinal absorption, which can be impaired in individuals with digestive conditions.

Physiological roles

Vitamin B12 is required for:

  • Energy metabolism and ATP production
  • Myelin formation to protect nerves
  • Healthy red blood cell production
  • DNA synthesis
  • Neurological function and mood regulation

Evidence summary

Research strongly supports Vitamin B12’s role in treating deficiency, supporting neurological health, and improving energy metabolism in deficient individuals. IV or intramuscular B12 is clinically used when absorption issues are present, such as in pernicious anaemia, gastric surgery, or certain gastrointestinal disorders.

Potential benefits

Supports energy levels and reduces fatigue

Helps maintain healthy nerve function

Reduced oxidative stress in certain conditions

Helps prevent or manage B12 deficiency anaemia

May support mood balance through neurotransmitter pathways

Safety profile

  • Generally very safe and well-tolerated.
  • Rare side effects include mild headache, acne, or transient flushing.
  • Caution in patients with Leber’s hereditary optic neuropathy.
  • High doses are typically safe as excess is excreted in urine.

Interactions

May interact with metformin (reduces B12 levels).

Long-term use of proton pump inhibitors and H2 blockers can impair absorption.

Can affect blood tests for certain biomarkers (e.g., folate interplay).

Evidence rating

Strong – extensive research supports its essential biological functions and clinical use in deficiency and neurological support.

References

  • O’Leary F, Samman S. Vitamin B12 in health and disease. Nutrients. 2010.

  • Langan RC, Zawistoski KJ. Update on vitamin B12 deficiency. Am Fam Physician.

  • NIH Office of Dietary Supplements – Vitamin B12 Fact Sheet.

  • PubMed clinical literature on cobalamin metabolism and deficiency.