Vitamin B12 content of foods

Food sources, levels of intake and nutrition status

Food sources
Vitamin B12 can only be synthesized in nature by bacteria and archae. It is present, albeit in very small quantities, in all foods of animal origin, due to the accumulation of the quantities synthesized by bacteria. The liver is particularly rich in it. Plant foods do not contain vitamin B12, unless they have been contaminated with microorganisms. You have no specific data relating to the vitamin B12 content in your country's diet, nor relating to the nutrition status for vitamin B 12 of your country's population.

Recommended intake levels
On the basis of studies for the evaluation of the nutritional status for vitamin B 12 (plasma levels of vitamin, plasma and urinary concentrations of methylmalonic acid, presence of macrocytic anemia, psychiatric tests) it was possible to establish a value of 1µd / day as a value average requirement for the normal adult. This requirement increases by approximately 20% during pregnancy and by 50% during breastfeeding. Considering the individual biological variation and the safety margin represented by the constitution of a good body reserve, it is recommended, in accordance with the American RDA and with the previous LARN, a quantity of 2 µg / day for the adult.
In strict vegetarian pregnant women and deficient infants a vitamin B12 supplement is recommended. In the absence of specific studies, the recommended values ​​for children are based on those of adults and proportionate to energy expenditure.

VITAMIN B12: DATI SINU-LARN SOURCE

1 The upper limits of the age range are intended up to the completion of the next birthday (for example "1 - 3 years" means from 1 year just completed until the completion of the 4th year). The last age group of the woman is "50 and more" because with the menopause the needs of two important nutrients change: calcium and iron. In humans, the last age group is "60 and over".

2 In infants, children and adolescents, the weight ranges are the reference values ​​taken from table 1 of the "Energy" chapter: the lower limit of the interval corresponds to the weight of females in the lowest age group, while the upper limit corresponds to the weight of males in the older age group. In adults, the mean desirable weight of males and females in your country's population was reported (see chapter "Energy").