Systematic review on daily vitamin B12 losses and bioavailability for deriving recommendations on vitamin B12 intake with the factorial approach
Doets EL, In 't Veld PH, Szczecińska A, Dhonukshe-Rutten RA, Cavelaars AE, van 't Veer P, et al.
Published in Ann Nutr Metab, Vol. 62 (4), pp. 311-22
Methodology
Systematic review of daily vitamin B12 losses and of B12 absorption from foods and diets in healthy adults and older adults.
Key Findings
Absorption of vitamin B12 ranged from 4.5% (a 38 µg dose from liver) to 83% (a 3.0 µg dose from mutton). Across eight studies in 83 people, the amount absorbed rose with the dose, but less than proportionally.
Conclusions
Daily losses are probably 1.4 to 5.1 µg, and the intake needed to cover them seems to range from 3.8 to 20.7 µg; more evidence is needed on biomarkers and long-term outcomes.
Limitations
Small absorption studies in healthy people, using different foods and methods; none tested people with deficiency.
Supplements Studied
dose of 38 µg from consumption of liver
Related Health Concerns
Study Details
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