Vitamin B12 is needed for folic acid production and proper cell function. Adults should get some 2 µg of vitamin B12 a day, while the recommended intake for children is 0.5 - 1.3 µg a day. Breastfeeding women should get approx. 2.6 µg/day of vitamin B12.
The most important vitamin B12 sources are meat dishes, dairy products and fish. Vegans are advised to take nutrition supplements containing vitamin B12 and iodine.