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Ingredient

Vitamin B12

Strong

An essential vitamin involved in red blood cell formation and energy metabolism.

How it works

Cofactor for methylmalonyl-CoA mutase and methionine synthase; deficiency is common in older adults and those on plant-based diets.

Evidence

Cochrane review of two RCTs concluded oral B12 at 1000-2000 mcg/day was as effective as intramuscular administration for treating B12 deficiency.

Studies

Vidal-Alaball et al., Cochrane Database Syst Rev, 2005
2000 mcg/day oral B12 (or 1000 mcg/day initially daily then weekly then monthly) achieved hematological and neurological responses comparable to intramuscular B12 in deficient patients.
PubMed 16034940 ↗

Top products

Sorted by effective monthly cost

Now Foods B12 1000 mg

Now Foods

Per serving: 1000 mg
Studied midpointStudied range midpoint is used. Pricing assumes label-recommended servings.See methodology: 1500 mg · 2/day

Buy at Amazon.ca

Nature Made B12 1000 mg

Nature Made

Per serving: 1000 mg
Studied midpointStudied range midpoint is used. Pricing assumes label-recommended servings.See methodology: 1500 mg · 2/day

Buy at Amazon.ca

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