What are the risks of a vitamin B-12 deficiency?
Untreated, the symptoms of vitamin B-12 deficiency can become permanent and lead to abnormalities of growth and mental retardation in children and severe systemic disorders in adults. Clinical manifestations of vitamin B-12 deficiency include anemia, neurological impairment, irritability, memory impairment, and depression. Deficiencies of B-12 have also been linked to multiple sclerosis-like symptoms and dementia. The role vitamin B-12 deficiency plays in the promotion of atherosclerosis is now being explored. Researchers have discovered that a deficiency raises blood levels of homocysteine, an amino acid in the blood. In addition to being toxic to brain cells in high doses—suggesting a possible role in Alzheimer’s disease–homocysteine may be one of the primary causes of heart disease. In some people, the accumulation of homocysteine may be caused by a genetic defect, while in others, it’s simply the result of a vitamin B-12 deficiency. People who have both a B-12 deficiency and raise
