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Brain levels of vitamin B12 decrease with age and are prematurely low in people with autism and schizophrenia -- ScienceDaily

An active form of B12 called methylcobalamin, or methyl B12, supports normal brain development by its control through a process known as epigenetic regulation of gene expression. Remarkably, the brain level of methyl B12 was found to be more than 10 times lower in healthy elderly people than in healthy younger people. A lower than normal level of methyl B12 in the brain could adversely affect neurodevelopment in younger years and could disrupt learning and memory later in life. Both autism and schizophrenia are associated with oxidative stress, which also plays an important role in aging, and oxidative stress may underlie the decreased brain B12 levels observed in this study. The findings suggest the need for further research to determine if the use of supplemental methyl B12 and antioxidants like glutathione could help prevent oxidative stress and be useful in treating these conditions.