Human requirement of vitamin B12
The Food and Nutrition Board recommends 3 mcg vitamin Bi2 per day for adults. The allowance during pregnancy and lactation is 4 mcg per day.
The Joint FAO/WHO Expert Group recommends 2 mcg per day for the adult (over 10 years of age). This allowance is increased to 3 mcg for the pregnant woman and 2.5 mcg for the nursing mother.
Pernicious anemia patients who have been treated to replenish their stores can meet their body needs with 1 mcg to 1.5 mcg BI2 daily, given intramuscularly, or a larger dose given intramuscularly once a month.
