Vitamin B12 is essential for the following body functions:
* the formation of blood cells and nerves
Sources of Vitamin B12:
| Food / 100g | Amount (µg) |
| Nori seaweed, dried | 27.5 |
| Anchovies, canned, drained | 11 |
| Cheddar cheese | 1.1 |
Dietary Reference Intake
| Life Stage Group | RDA/AI* µg / day | Upper Limit µg / day |
| Infants 0-6 months 7-12 months | 0.4* 0.5* | Not determinable Not determinable |
| Children 1-3 years 4-8 years | 0.9 1.2 | Not determinable Not determinable |
| Males 9-13 years 14-18 years 19 – >70 years | 1.8 2.4 2.4 | Not determinable Not determinable Not determinable |
| Females 9-13 years 14-18 years 19 – >70 years | 1.8 2.4 2.4 | Not determinable Not determinable Not determinable |
| Pregnancy <19 years 19 – >50 years | 2.6 2.6 | Not determinable Not determinable |
| Lactation <19 years 19 – >50 years | 2.8 2.8 | Not determinable Not determinable |
RDA = Recommended Dietary Allowances
AI* = Adequate Intakes
UL = Upper Limit
Vitamin B12 Deficiency
A deficiency of vitamin B12 can cause:
* pernicious anaemia
* nerve damage
Vitamin B12 Overdose
High intake of vitamin B12 appears to have no toxic effects.