Sporadic evidence from childhood practices that there is a benefit for folic acid supplementation for autistic children and those patients are encouraged to take folic acid as a medication. Meta-analysis studies are needed to study the cause-specific effect of folic acid deficiency and/or hyperhomocysteinemia on the autism incidence.
There is a need for clinical trials to specifically study the role of folic acid in the primary and secondary prevention of autism. Sporadic evidence from childhood practices that there is a benefit for folic acid supplementation for autistic children and those patients are encouraged to take folic acid as a medication. Meta-analysis studies are needed to study the cause-specific effect of folic acid deficiency and/or hyperhomocysteinemia on the autism incidence.
You may have long ago solved this problem; however, my comments follow.
Be aware of the need to distinguish between folic acid and folate. Folic acid is more stable and is used in fortification but can block the receptor and prevent dietary folates from being active. I would suggest a nutrigenetic analysis of the genes associated with methylation - MTHFR is a key gene and is necessary for folate metabolism to proceed as needed. If the patient carries less functional polymorphisms of this gene, select 5-methyl folate as the preferred supplement as it bypasses the metabolic block.