Vitamin B12
Also known as: Cobalamin · Methylcobalamin · Cyanocobalamin · Hydroxocobalamin
An essential water-soluble vitamin often given by injection to correct deficiency and support energy, nerve function, and healthy red blood cells.
Vitamin B12 at a glance
| Name | Vitamin B12 |
|---|---|
| Also known as | Cobalamin, Methylcobalamin, Cyanocobalamin, Hydroxocobalamin |
| Category | Energy & metabolism |
| Type | Amino / injectable |
| Sequence | Cobalamin — a cobalt-containing vitamin (forms: methyl-, cyano-, hydroxo-, adenosyl-) |
| Typical dose | ~1000 mcg |
| Frequency | Weekly to monthly for maintenance (deficiency protocols vary) |
| Route | Intramuscular or subcutaneous injection |
| Half-life | Variable; the body stores B12 in the liver, so levels decline slowly over months. |
Overview
Vitamin B12 (cobalamin) is an essential nutrient the body cannot make on its own. It is central to red-blood-cell formation, nerve-cell health, and DNA synthesis. Because absorbing B12 from food depends on healthy gut and stomach function, injections are commonly used to bypass absorption problems and rapidly restore levels — which is why B12 shots are a fixture of wellness and energy clinics. Methylcobalamin and hydroxocobalamin are the forms most often used in injections.
How it’s thought to work
- Acts as a cofactor for methionine synthase, supporting methylation and homocysteine metabolism.
- Required by methylmalonyl-CoA mutase for energy metabolism from fats and proteins.
- Supports myelin (the protective sheath around nerves) and red-blood-cell production.
Researched uses
- Correcting B12 deficiency and related anemia
- Fatigue and low energy where deficiency is present
- Nerve health; commonly included in wellness injection blends
Commonly cited protocol
| Typical dose | ~1000 mcg |
|---|---|
| Frequency | Weekly to monthly for maintenance (deficiency protocols vary) |
| Route | Intramuscular or subcutaneous injection |
| Notes | Water-soluble — excess is largely excreted rather than stored to excess. |
Reconstitution
B12 is usually supplied as a ready-to-inject solution (commonly 1000 mcg/mL), so lyophilized-vial reconstitution is typically not needed.
Cautions
- Generally very safe and water-soluble, but confirm dosing and deficiency with a clinician and bloodwork.
- Rare allergic reactions to injectable forms (often the preservative).
- Not a stimulant — “energy” benefits are mainly seen when correcting a true deficiency.
Vitamin B12 FAQ
What is Vitamin B12?
An essential water-soluble vitamin often given by injection to correct deficiency and support energy, nerve function, and healthy red blood cells.
How does Vitamin B12 work?
Acts as a cofactor for methionine synthase, supporting methylation and homocysteine metabolism. Required by methylmalonyl-CoA mutase for energy metabolism from fats and proteins. Supports myelin (the protective sheath around nerves) and red-blood-cell production.
What is Vitamin B12 used for?
Correcting B12 deficiency and related anemia; Fatigue and low energy where deficiency is present; Nerve health; commonly included in wellness injection blends.
What is a typical Vitamin B12 dose?
~1000 mcg, Weekly to monthly for maintenance (deficiency protocols vary), Intramuscular or subcutaneous injection. This is a commonly cited figure for context only, not medical advice.
How do you reconstitute Vitamin B12?
B12 is usually supplied as a ready-to-inject solution (commonly 1000 mcg/mL), so lyophilized-vial reconstitution is typically not needed.
What is the half-life of Vitamin B12?
Variable; the body stores B12 in the liver, so levels decline slowly over months.