Vitamine B12 = (cyano)cobalamine
Contains the porphyrin ring: which complexes metals such as iron (in hemoglobin) or magnesium (in chlorophyll)
only animal: - some bacteria of herbivores produce it - is passed from herbivores to carnivores so that all products of animal origin contain it, but not plants:
essential - normal functioning of the brain and nervous system - to the production of blood intervenes in - the synthesis of DNA - the regulation of DNA - the synthesis of fatty acids - in the production of energy.
adult: 2.5-6 µg / d
Possible in strictly vegetarian diet without supplements: - anemia (called pernicious) - sclerosis of the spinal cord - thromboses