Vitamin B12 Deficiency
Vitamin B12 (cyanocobalamin) is essential for the functioning of all cells, but especially for the cells of the bone marrow, the central nervous system, and the intestinal tract. It is thought to be involved in the metabolism of protein, carbohydrates, and fats.
The most serious manifestation of B12 deficiency is pernicious anemia, so called because it once was invariably fatal. Pernicious anemia leads to a general muscular weakness and signs of deterioration of the central nervous system. Skin pallor, heart palpitations, and eventually more severe heart disturbances are also symptoms, as are a sore, red, inflamed-looking tongue which eventually becomes smooth and glazed.
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