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With respect to dosage, the average reductions were: 2000 mcg: 71.5% (single data point) 1,000 mcg: 31.8% Although limited data are available for higher dosages, the findings support the efficacy of both oral and non-oral B12 formulations in modulating homocysteine levels
Endocrinology , 142(2), 626632
What this implies: if the vial remains sealed, in a cool, dry, dark place (ideally under refrigeration or freezing, with minimal humidity), you can reasonably expect 2-3 years of viability in the lyophilized state
Severe deficiency cases may result in pernicious anemia, typified by the development of abnormally large red blood cells
The blood level of methylmalonic acid increases when a person has B 12 deficiency