Why is elevated b12 serum found in autistic children?

Not elevated: I am not aware that vitamin b 12 is elevated in autistic children.

Not always seen: More often i will see low or normal levels of B12 unless there is supplementation. This vitamin has a fairly complicated absorption process and is not efficient in some. If there is gut inflammation or infection or if there is an autoimmune process oral intake is not effective and you have to move to sublingual or injections. B12 works closely with folate (folic acid) and b6 and very often all need to be used.

Glutathione, both : Reduced & oxidized, is low in children with autism. A mind institute study showed that methyl B12 injections were ineffective in treating behavioral symptoms of autism, except in 30% of subjects who had significant increases in plasma levels of both types of glutathione.Ongoing research is being done to find biomarkers that identify children who may respond. High b 12 levels aren't found in asd.