Vitamin B12 Deficiency

Vitamin B12 Deficiency

Vitamin B₁₂ deficiency or hypocobalaminemia is a low blood level of vitamin B₁₂. It can cause permanent damage to nervous tissue if left untreated longer than 6 months. Vitamin B₁₂ itself was discovered through investigation of pernicious anemia, which is an autoimmune disease that destroys parietal cells in the stomach that secrete intrinsic factor. Pernicious anemia, if left untreated, is usually fatal within three years. Once identified, however, the condition can be treated successfully and with relative ease, although it cannot be cured and ongoing treatment is required. Humans obtain almost all of their vitamin B₁₂ from dietary means. Pernicious anemia is usually the result of insufficient secretion of intrinsic factor within the stomach. Other more subtle types of vitamin B₁₂ deficiency have been elucidated, including the biochemical effects, over the course of time in significant numbers.

The results of the Framingham Offspring Study indicate that B₁₂ deficiency may be more common than was previously believed. Deficiency is most significantly linked to improper absorption rather than low consumption, as many who consume high amounts of B₁₂ may still experience deficiency.